Mercredi 24 juin 2026

Red Hat Container Native Virtualization 4.12 · Red Hat Container Native Virtualization 4.13 · Red Hat Container Native Virtualization 4.14 · Red Hat Container Native Virtualization 4.15

A flaw was found in KubeVirt's safepath package used by virt-handler. The OpenAtNoFollow function uses O_PATH|O_NOFOLLOW to obtain a file descriptor to a path leaf, but downstream operations resolve the path via /proc/self/fd/N using link-following syscalls. When the leaf is a symlink, the kernel dereferences it, defeating the intended no-follow protection. An attacker with access to a virt-launcher pod can exploit this to redirect virt-handler's IPC socket connections, including the notify socket used for VM domain lifecycle events. By hijacking this socket, the attacker can inject arbitrary domain events into virt-handler, causing it to take incorrect lifecycle actions, corrupt VM state in the Kubernetes API, or crash — resulting in sustained denial of VM management services for all virtual machines on the affected node. Additionally, the same symlink following flaw allows virt-handler to apply file ownership or permission changes to unintended host paths.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: fs/omfs: reject s_sys_blocksize smaller than OMFS_DIR_START omfs_fill_super() rejects oversized s_sys_blocksize values (> PAGE_SIZE), but it does not reject values smaller than OMFS_DIR_START (0x1b8 = 440). Later, omfs_make_empty() uses sbi->s_sys_blocksize - OMFS_DIR_START as the length argument to memset(). Since s_sys_blocksize is u32, a crafted filesystem image with s_sys_blocksize < OMFS_DIR_START causes an unsigned underflow there, wrapping to a value near 2^32. That drives a ~4 GiB memset() from bh->b_data + OMFS_DIR_START and overwrites kernel memory far beyond the backing block buffer. Add the corresponding lower-bound check alongside the existing upper-bound check in omfs_fill_super(), so that malformed images are rejected during superblock validation before any filesystem data is processed.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: fs/mbcache: cancel shrink work before destroying the cache mb_cache_destroy() calls shrinker_free() and then frees all cache entries and the cache itself, but it does not cancel the pending c_shrink_work work item first. If mb_cache_entry_create() schedules c_shrink_work via schedule_work() and the work item is still pending or running when mb_cache_destroy() runs, mb_cache_shrink_worker() will access the cache after its memory has been freed, causing a use-after-free. This is only reachable by a privileged user (root or CAP_SYS_ADMIN) who can trigger the last put of a mounted ext2/ext4/ocfs2 filesystem. Cancel the work item with cancel_work_sync() before calling shrinker_free(), ensuring the worker has finished and will not be rescheduled before the cache is torn down.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: PCI: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: platform/wmi: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: vdpa: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: s390/cio: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: s390/ap: use generic driver_override infrastructure When the AP masks are updated via apmask_store() or aqmask_store(), ap_bus_revise_bindings() is called after ap_attr_mutex has been released. This calls __ap_revise_reserved(), which accesses the driver_override field without holding any lock, racing against a concurrent driver_override_store() that may free the old string, resulting in a potential UAF. Fix this by using the driver-core driver_override infrastructure, which protects all accesses with an internal spinlock. Note that unlike most other buses, the AP bus does not check driver_override in its match() callback; the override is checked in ap_device_probe() and __ap_revise_reserved() instead. Also note that we do not enable the driver_override feature of struct bus_type, as AP - in contrast to most other buses - passes "" to sysfs_emit() when the driver_override pointer is NULL. Thus, printing "\n" instead of "(null)\n". Additionally, AP has a custom counter that is modified in the corresponding custom driver_override_store().

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc: use generic driver_override infrastructure When a driver is probed through __driver_attach(), the bus' match() callback is called without the device lock held, thus accessing the driver_override field without a lock, which can cause a UAF. Fix this by using the driver-core driver_override infrastructure taking care of proper locking internally. Note that calling match() from __driver_attach() without the device lock held is intentional. [1]

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: wifi: rtlwifi: pci: fix possible use-after-free caused by unfinished irq_prepare_bcn_tasklet The irq_prepare_bcn_tasklet is initialized in rtl_pci_init() and scheduled when RTL_IMR_BCNINT interrupt is triggered by hardware. But it is never killed in rtl_pci_deinit(). When the rtlwifi card probe fails or is being detached, the ieee80211_hw is deallocated. However, irq_prepare_bcn_tasklet may still be running or pending, leading to use-after-free when the freed ieee80211_hw is accessed in _rtl_pci_prepare_bcn_tasklet(). Similar to irq_tasklet, add tasklet_kill() in rtl_pci_deinit() to ensure that irq_prepare_bcn_tasklet is properly terminated before the ieee80211_hw is released. The issue was identified through static analysis.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: s390/bpf: Zero-extend bpf prog return values and kfunc arguments s390x ABI requires callers to zero-extend unsigned arguments and sign-extend signed arguments, and callees to zero-extend unsigned return values and sign-extend signed return values. s390 BPF JIT currently implements only sign extension. Fix this omission and implement zero extension too.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: powerpc/pgtable-frag: Fix bad page state in pte_frag_destroy powerpc uses pt_frag_refcount as a reference counter for tracking it's pte and pmd page table fragments. For PTE table, in case of Hash with 64K pagesize, we have 16 fragments of 4K size in one 64K page. Patch series [1] "mm: free retracted page table by RCU" added pte_free_defer() to defer the freeing of PTE tables when retract_page_tables() is called for madvise MADV_COLLAPSE on shmem range. [1]: https://lore.kernel.org/all/7cd843a9-aa80-14f-5eb2-33427363c20@google.com/ pte_free_defer() sets the active flag on the corresponding fragment's folio & calls pte_fragment_free(), which reduces the pt_frag_refcount. When pt_frag_refcount reaches 0 (no active fragment using the folio), it checks if the folio active flag is set, if set, it calls call_rcu to free the folio, it the active flag is unset then it calls pte_free_now(). Now, this can lead to following problem in a corner case... [ 265.351553][ T183] BUG: Bad page state in process a.out pfn:20d62 [ 265.353555][ T183] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20d62 [ 265.355457][ T183] flags: 0x3ffff800000100(active|node=0|zone=0|lastcpupid=0x7ffff) [ 265.358719][ T183] raw: 003ffff800000100 0000000000000000 5deadbeef0000122 0000000000000000 [ 265.360177][ T183] raw: 0000000000000000 c0000000119caf58 00000000ffffffff 0000000000000000 [ 265.361438][ T183] page dumped because: PAGE_FLAGS_CHECK_AT_FREE flag(s) set [ 265.362572][ T183] Modules linked in: [ 265.364622][ T183] CPU: 0 UID: 0 PID: 183 Comm: a.out Not tainted 6.18.0-rc3-00141-g1ddeaaace7ff-dirty #53 VOLUNTARY [ 265.364785][ T183] Hardware name: IBM pSeries (emulated by qemu) POWER10 (architected) 0x801200 0xf000006 of:SLOF,git-ee03ae pSeries [ 265.364908][ T183] Call Trace: [ 265.364955][ T183] [c000000011e6f7c0] [c000000001cfaa18] dump_stack_lvl+0x130/0x148 (unreliable) [ 265.365202][ T183] [c000000011e6f7f0] [c000000000794758] bad_page+0xb4/0x1c8 [ 265.365384][ T183] [c000000011e6f890] [c00000000079c020] __free_frozen_pages+0x838/0xd08 [ 265.365554][ T183] [c000000011e6f980] [c0000000000a70ac] pte_frag_destroy+0x298/0x310 [ 265.365729][ T183] [c000000011e6fa30] [c0000000000aa764] arch_exit_mmap+0x34/0x218 [ 265.365912][ T183] [c000000011e6fa80] [c000000000751698] exit_mmap+0xb8/0x820 [ 265.366080][ T183] [c000000011e6fc30] [c0000000001b1258] __mmput+0x98/0x300 [ 265.366244][ T183] [c000000011e6fc80] [c0000000001c81f8] do_exit+0x470/0x1508 [ 265.366421][ T183] [c000000011e6fd70] [c0000000001c95e4] do_group_exit+0x88/0x148 [ 265.366602][ T183] [c000000011e6fdc0] [c0000000001c96ec] pid_child_should_wake+0x0/0x178 [ 265.366780][ T183] [c000000011e6fdf0] [c00000000003a270] system_call_exception+0x1b0/0x4e0 [ 265.366958][ T183] [c000000011e6fe50] [c00000000000d05c] system_call_vectored_common+0x15c/0x2ec The bad page state error occurs when such a folio gets freed (with active flag set), from do_exit() path in parallel. ... this can happen when the pte fragment was allocated from this folio, but when all the fragments get freed, the pte_frag_refcount still had some unused fragments. Now, if this process exits, with such folio as it's cached pte_frag in mm->context, then during pte_frag_destroy(), we simply call pagetable_dtor() and pagetable_free(), meaning it doesn't clear the active flag. This, can lead to the above bug. Since we are anyway in do_exit() path, then if the refcount is 0, then I guess it should be ok to simply clear the folio active flag before calling pagetable_dtor() & pagetable_free().

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7915: fix use-after-free bugs in mt7915_mac_dump_work() When the mt7915 pci chip is detaching, the mt7915_crash_data is released in mt7915_coredump_unregister(). However, the work item dump_work may still be running or pending, leading to UAF bugs when the already freed crash_data is dereferenced again in mt7915_mac_dump_work(). The race condition can occur as follows: CPU 0 (removal path) | CPU 1 (workqueue) mt7915_pci_remove() | mt7915_sys_recovery_set() mt7915_unregister_device() | mt7915_reset() mt7915_coredump_unregister() | queue_work() vfree(dev->coredump.crash_data) | mt7915_mac_dump_work() | crash_data-> // UAF Fix this by ensuring dump_work is properly canceled before the crash_data is deallocated. Add cancel_work_sync() in mt7915_unregister_device() to synchronize with any pending or executing dump work.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7996: fix use-after-free bugs in mt7996_mac_dump_work() When the mt7996 pci chip is detaching, the mt7996_crash_data is released in mt7996_coredump_unregister(). However, the work item dump_work may still be running or pending, leading to UAF bugs when the already freed crash_data is dereferenced again in mt7996_mac_dump_work(). The race condition can occur as follows: CPU 0 (removal path) | CPU 1 (workqueue) mt7996_pci_remove() | mt7996_sys_recovery_set() mt7996_unregister_device() | mt7996_reset() mt7996_coredump_unregister() | queue_work() vfree(dev->coredump.crash_data) | mt7996_mac_dump_work() | crash_data-> // UAF Fix this by ensuring dump_work is properly canceled before the crash_data is deallocated. Add cancel_work_sync() in mt7996_unregister_device() to synchronize with any pending or executing dump work.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Use RCU-safe iteration in dev_map_redirect_multi() SKB path The DEVMAP_HASH branch in dev_map_redirect_multi() uses hlist_for_each_entry_safe() to iterate hash buckets, but this function runs under RCU protection (called from xdp_do_generic_redirect_map() in softirq context). Concurrent writers (__dev_map_hash_update_elem, dev_map_hash_delete_elem) modify the list using RCU primitives (hlist_add_head_rcu, hlist_del_rcu). hlist_for_each_entry_safe() performs plain pointer dereferences without rcu_dereference(), missing the acquire barrier needed to pair with writers' rcu_assign_pointer(). On weakly-ordered architectures (ARM64, POWER), a reader can observe a partially-constructed node. It also defeats CONFIG_PROVE_RCU lockdep validation and KCSAN data-race detection. Replace with hlist_for_each_entry_rcu() using rcu_read_lock_bh_held() as the lockdep condition, consistent with the rcu_dereference_check() used in the DEVMAP (non-hash) branch of the same functions. Also fix the same incorrect lockdep_is_held(&dtab->index_lock) condition in dev_map_enqueue_multi(), where the lock is not held either.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix stale offload->prog pointer after constant blinding When a dev-bound-only BPF program (BPF_F_XDP_DEV_BOUND_ONLY) undergoes JIT compilation with constant blinding enabled (bpf_jit_harden >= 2), bpf_jit_blind_constants() clones the program. The original prog is then freed in bpf_jit_prog_release_other(), which updates aux->prog to point to the surviving clone, but fails to update offload->prog. This leaves offload->prog pointing to the freed original program. When the network namespace is subsequently destroyed, cleanup_net() triggers bpf_dev_bound_netdev_unregister(), which iterates ondev->progs and calls __bpf_prog_offload_destroy(offload->prog). Accessing the freed prog causes a page fault: BUG: unable to handle page fault for address: ffffc900085f1038 Workqueue: netns cleanup_net RIP: 0010:__bpf_prog_offload_destroy+0xc/0x80 Call Trace: __bpf_offload_dev_netdev_unregister+0x257/0x350 bpf_dev_bound_netdev_unregister+0x4a/0x90 unregister_netdevice_many_notify+0x2a2/0x660 ... cleanup_net+0x21a/0x320 The test sequence that triggers this reliably is: 1. Set net.core.bpf_jit_harden=2 (echo 2 > /proc/sys/net/core/bpf_jit_harden) 2. Run xdp_metadata selftest, which creates a dev-bound-only XDP program on a veth inside a netns (./test_progs -t xdp_metadata) 3. cleanup_net -> page fault in __bpf_prog_offload_destroy Dev-bound-only programs are unique in that they have an offload structure but go through the normal JIT path instead of bpf_prog_offload_compile(). This means they are subject to constant blinding's prog clone-and-replace, while also having offload->prog that must stay in sync. Fix this by updating offload->prog in bpf_jit_prog_release_other(), alongside the existing aux->prog update. Both are back-pointers to the prog that must be kept in sync when the prog is replaced.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix linked reg delta tracking when src_reg == dst_reg Consider the case of rX += rX where src_reg and dst_reg are pointers to the same bpf_reg_state in adjust_reg_min_max_vals(). The latter first modifies the dst_reg in-place, and later in the delta tracking, the subsequent is_reg_const(src_reg)/reg_const_value(src_reg) reads the post-{add,sub} value instead of the original source. This is problematic since it sets an incorrect delta, which sync_linked_regs() then propagates to linked registers, thus creating a verifier-vs-runtime mismatch. Fix it by just skipping this corner case.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 6

In the Linux kernel, the following vulnerability has been resolved: net: pull headers in qdisc_pkt_len_segs_init() Most ndo_start_xmit() methods expects headers of gso packets to be already in skb->head. net/core/tso.c users are particularly at risk, because tso_build_hdr() does a memcpy(hdr, skb->data, hdr_len); qdisc_pkt_len_segs_init() already does a dissection of gso packets. Use pskb_may_pull() instead of skb_header_pointer() to make sure drivers do not have to reimplement this. Some malicious packets could be fed, detect them so that we can drop them sooner with a new SKB_DROP_REASON_SKB_BAD_GSO drop_reason.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix ld_{abs,ind} failure path analysis in subprogs Usage of ld_{abs,ind} instructions got extended into subprogs some time ago via commit 09b28d76eac4 ("bpf: Add abnormal return checks."). These are only allowed in subprograms when the latter are BTF annotated and have scalar return types. The code generator in bpf_gen_ld_abs() has an abnormal exit path (r0=0 + exit) from legacy cBPF times. While the enforcement is on scalar return types, the verifier must also simulate the path of abnormal exit if the packet data load via ld_{abs,ind} failed. This is currently not the case. Fix it by having the verifier simulate both success and failure paths, and extend it in similar ways as we do for tail calls. The success path (r0=unknown, continue to next insn) is pushed onto stack for later validation and the r0=0 and return to the caller is done on the fall-through side.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix use-after-free in offloaded map/prog info fill When querying info for an offloaded BPF map or program, bpf_map_offload_info_fill_ns() and bpf_prog_offload_info_fill_ns() obtain the network namespace with get_net(dev_net(offmap->netdev)). However, the associated netdev's netns may be racing with teardown during netns destruction. If the netns refcount has already reached 0, get_net() performs a refcount_t increment on 0, triggering: refcount_t: addition on 0; use-after-free. Although rtnl_lock and bpf_devs_lock ensure the netdev pointer remains valid, they cannot prevent the netns refcount from reaching zero. Fix this by using maybe_get_net() instead of get_net(). maybe_get_net() uses refcount_inc_not_zero() and returns NULL if the refcount is already zero, which causes ns_get_path_cb() to fail and the caller to return -ENOENT -- the correct behavior when the netns is being destroyed.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net: bcmgenet: fix leaking free_bds While reclaiming the tx queue we fast forward the write pointer to drop any data in flight. These dropped frames are not added back to the pool of free bds. We also need to tell the netdev that we are dropping said data.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: bpf: fix mm lifecycle in open-coded task_vma iterator The open-coded task_vma iterator reads task->mm locklessly and acquires mmap_read_trylock() but never calls mmget(). If the task exits concurrently, the mm_struct can be freed as it is not SLAB_TYPESAFE_BY_RCU, resulting in a use-after-free. Safely read task->mm with a trylock on alloc_lock and acquire an mm reference. Drop the reference via bpf_iter_mmput_async() in _destroy() and error paths. bpf_iter_mmput_async() is a local wrapper around mmput_async() with a fallback to mmput() on !CONFIG_MMU. Reject irqs-disabled contexts (including NMI) up front. Operations used by _next() and _destroy() (mmap_read_unlock, bpf_iter_mmput_async) take spinlocks with IRQs disabled (pool->lock, pi_lock). Running from NMI or from a tracepoint that fires with those locks held could deadlock. A trylock on alloc_lock is used instead of the blocking task_lock() (get_task_mm) to avoid a deadlock when a softirq BPF program iterates a task that already holds its alloc_lock on the same CPU.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: bpf: Enforce regsafe base id consistency for BPF_ADD_CONST scalars When regsafe() compares two scalar registers that both carry BPF_ADD_CONST, check_scalar_ids() maps their full compound id (aka base | BPF_ADD_CONST flag) as one idmap entry. However, it never verifies that the underlying base ids, that is, with the flag stripped are consistent with existing idmap mappings. This allows construction of two verifier states where the old state has R3 = R2 + 10 (both sharing base id A) while the current state has R3 = R4 + 10 (base id C, unrelated to R2). The idmap creates two independent entries: A->B (for R2) and A|flag->C|flag (for R3), without catching that A->C conflicts with A->B. State pruning then incorrectly succeeds. Fix this by additionally verifying base ID mapping consistency whenever BPF_ADD_CONST is set: after mapping the compound ids, also invoke check_ids() on the base IDs (flag bits stripped). This ensures that if A was already mapped to B from comparing the source register, any ADD_CONST derivative must also derive from B, not an unrelated C.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix same-register dst/src OOB read and pointer leak in sock_ops When a BPF sock_ops program accesses ctx fields with dst_reg == src_reg, the SOCK_OPS_GET_SK() and SOCK_OPS_GET_FIELD() macros fail to zero the destination register in the !fullsock / !locked_tcp_sock path. Both macros borrow a temporary register to check is_fullsock / is_locked_tcp_sock when dst_reg == src_reg, because dst_reg holds the ctx pointer. When the check is false (e.g., TCP_NEW_SYN_RECV state with a request_sock), dst_reg should be zeroed but is not, leaving the stale ctx pointer: - SOCK_OPS_GET_SK: dst_reg retains the ctx pointer, passes NULL checks as PTR_TO_SOCKET_OR_NULL, and can be used as a bogus socket pointer, leading to stack-out-of-bounds access in helpers like bpf_skc_to_tcp6_sock(). - SOCK_OPS_GET_FIELD: dst_reg retains the ctx pointer which the verifier believes is a SCALAR_VALUE, leaking a kernel pointer. Fix both macros by: - Changing JMP_A(1) to JMP_A(2) in the fullsock path to skip the added instruction. - Adding BPF_MOV64_IMM(si->dst_reg, 0) after the temp register restore in the !fullsock path, placed after the restore because dst_reg == src_reg means we need src_reg intact to read ctx->temp.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net/rds: Restrict use of RDS/IB to the initial network namespace Prevent using RDS/IB in network namespaces other than the initial one. The existing RDS/IB code will not work properly in non-initial network namespaces.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix OOB in pcpu_init_value An out-of-bounds read occurs when copying element from a BPF_MAP_TYPE_CGROUP_STORAGE map to another pcpu map with the same value_size that is not rounded up to 8 bytes. The issue happens when: 1. A CGROUP_STORAGE map is created with value_size not aligned to 8 bytes (e.g., 4 bytes) 2. A pcpu map is created with the same value_size (e.g., 4 bytes) 3. Update element in 2 with data in 1 pcpu_init_value assumes that all sources are rounded up to 8 bytes, and invokes copy_map_value_long to make a data copy, However, the assumption doesn't stand since there are some cases where the source may not be rounded up to 8 bytes, e.g., CGROUP_STORAGE, skb->data. the verifier verifies exactly the size that the source claims, not the size rounded up to 8 bytes by kernel, an OOB happens when the source has only 4 bytes while the copy size(4) is rounded up to 8.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: ppp: require CAP_NET_ADMIN in target netns for unattached ioctls /dev/ppp open is currently authorized against file->f_cred->user_ns, while unattached administrative ioctls operate on current->nsproxy->net_ns. As a result, a local unprivileged user can create a new user namespace with CLONE_NEWUSER, gain CAP_NET_ADMIN only in that new user namespace, and still issue PPPIOCNEWUNIT, PPPIOCATTACH, or PPPIOCATTCHAN against an inherited network namespace. Require CAP_NET_ADMIN in the user namespace that owns the target network namespace before handling unattached PPP administrative ioctls. This preserves normal pppd operation in the network namespace it is actually privileged in, while rejecting the userns-only inherited-netns case.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls hci_connect_cfm(conn) without hdev->lock. Generally hci_connect_cfm() assumes it is held, and if conn is deleted concurrently -> UAF. Only SCO and ISO set HCI_PROTO_DEFER and only for defer setup listen, and HCI_EV_CONN_REQUEST is not generated for ISO. In the non-deferred listening socket code paths, hci_connect_cfm(conn) is called with hdev->lock held. Fix by holding the lock.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: l2cap: Add missing chan lock in l2cap_ecred_reconf_rsp l2cap_ecred_reconf_rsp() calls l2cap_chan_del() without holding l2cap_chan_lock(). Every other l2cap_chan_del() caller in the file acquires the lock first. A remote BLE device can send a crafted L2CAP ECRED reconfiguration response to corrupt the channel list while another thread is iterating it. Add l2cap_chan_hold() and l2cap_chan_lock() before l2cap_chan_del(), and l2cap_chan_unlock() and l2cap_chan_put() after, matching the pattern used in l2cap_ecred_conn_rsp() and l2cap_conn_del().

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: sctp: disable BH before calling udp_tunnel_xmit_skb() udp_tunnel_xmit_skb() / udp_tunnel6_xmit_skb() are expected to run with BH disabled. After commit 6f1a9140ecda ("add xmit recursion limit to tunnel xmit functions"), on the path: udp(6)_tunnel_xmit_skb() -> ip(6)tunnel_xmit() dev_xmit_recursion_inc()/dec() must stay balanced on the same CPU. Without local_bh_disable(), the context may move between CPUs, which can break the inc/dec pairing. This may lead to incorrect recursion level detection and cause packets to be dropped in ip(6)_tunnel_xmit() or __dev_queue_xmit(). Fix it by disabling BH around both IPv4 and IPv6 SCTP UDP xmit paths. In my testing, after enabling the SCTP over UDP: # ip net exec ha sysctl -w net.sctp.udp_port=9899 # ip net exec ha sysctl -w net.sctp.encap_port=9899 # ip net exec hb sysctl -w net.sctp.udp_port=9899 # ip net exec hb sysctl -w net.sctp.encap_port=9899 # ip net exec ha iperf3 -s - without this patch: # ip net exec hb iperf3 -c 192.168.0.1 --sctp [ 5] 0.00-10.00 sec 37.2 MBytes 31.2 Mbits/sec sender [ 5] 0.00-10.00 sec 37.1 MBytes 31.1 Mbits/sec receiver - with this patch: # ip net exec hb iperf3 -c 192.168.0.1 --sctp [ 5] 0.00-10.00 sec 3.14 GBytes 2.69 Gbits/sec sender [ 5] 0.00-10.00 sec 3.14 GBytes 2.69 Gbits/sec receiver

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master syzkaller reported a kernel panic in bond_rr_gen_slave_id() reached via xdp_master_redirect(). Full decoded trace: https://syzkaller.appspot.com/bug?extid=80e046b8da2820b6ba73 bond_rr_gen_slave_id() dereferences bond->rr_tx_counter, a per-CPU counter that bonding only allocates in bond_open() when the mode is round-robin. If the bond device was never brought up, rr_tx_counter stays NULL. The XDP redirect path can still reach that code on a bond that was never opened: bpf_master_redirect_enabled_key is a global static key, so as soon as any bond device has native XDP attached, the XDP_TX -> xdp_master_redirect() interception is enabled for every slave system-wide. The path xdp_master_redirect() -> bond_xdp_get_xmit_slave() -> bond_xdp_xmit_roundrobin_slave_get() -> bond_rr_gen_slave_id() then runs against a bond that has no rr_tx_counter and crashes. Fix this in the generic xdp_master_redirect() by refusing to call into the master's ->ndo_xdp_get_xmit_slave() when the master device is not up. IFF_UP is only set after ->ndo_open() has successfully returned, so this reliably excludes masters whose XDP state has not been fully initialized. Drop the frame with XDP_ABORTED so the exception is visible via trace_xdp_exception() rather than silently falling through. This is not specific to bonding: any current or future master that defers XDP state allocation to ->ndo_open() is protected.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: drm/komeda: fix integer overflow in AFBC framebuffer size check The AFBC framebuffer size validation calculates the minimum required buffer size by adding the AFBC payload size to the framebuffer offset. This addition is performed without checking for integer overflow. If the addition oveflows, the size check may incorrectly succed and allow userspace to provide an undersized drm_gem_object, potentially leading to out-of-bounds memory access. Add usage of check_add_overflow() to safely compute the minimum required size and reject the framebuffer if an overflow is detected. This makes the AFBC size validation more robust against malformed. Found by Linux Verification Center (linuxtesting.org) with SVACE.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: PCI: endpoint: pci-ep-msi: Fix error unwind and prevent double alloc pci_epf_alloc_doorbell() stores the allocated doorbell message array in epf->db_msg/epf->num_db before requesting MSI vectors. If MSI allocation fails, the array is freed but the EPF state may still point to freed memory. Clear epf->db_msg and epf->num_db on the MSI allocation failure path so that later cleanup cannot double-free the array and callers can retry allocation. Also return -EBUSY when doorbells have already been allocated to prevent leaking or overwriting an existing allocation.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: dm cache policy smq: fix missing locks in invalidating cache blocks In passthrough mode, the policy invalidate_mapping operation is called simultaneously from multiple workers, thus it should be protected by a lock. Otherwise, we might end up with data races on the allocated blocks counter, or even use-after-free issues with internal data structures when doing concurrent writes. Note that the existing FIXME in smq_invalidate_mapping() doesn't affect passthrough mode since migration tasks don't exist there, but would need attention if supporting fast device shrinking via suspend/resume without target reloading. Reproduce steps: 1. Create a cache device consisting of 1024 cache entries dmsetup create cmeta --table "0 8192 linear /dev/sdc 0" dmsetup create cdata --table "0 131072 linear /dev/sdc 8192" dmsetup create corig --table "0 262144 linear /dev/sdc 262144" dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1 oflag=direct dmsetup create cache --table "0 262144 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0" 2. Populate the cache, and record the number of cached blocks fio --name=populate --filename=/dev/mapper/cache --rw=randwrite --bs=4k \ --size=64m --direct=1 nr_cached=$(dmsetup status cache | awk '{split($7, a, "/"); print a[1]}') 3. Reload the cache into passthrough mode dmsetup suspend cache dmsetup reload cache --table "0 262144 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 passthrough smq 0" dmsetup resume cache 4. Write to the passthrough cache. By setting multiple jobs with I/O size equal to the cache block size, cache blocks are invalidated concurrently from different workers. fio --filename=/dev/mapper/cache --name=test --rw=randwrite --bs=64k \ --direct=1 --numjobs=2 --randrepeat=0 --size=64m 5. Check if demoted matches cached block count. These numbers should match but may differ due to the data race. nr_demoted=$(dmsetup status cache | awk '{print $12}') echo "$nr_cached, $nr_demoted"

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat Enterprise Linux 7 Extended Lifecycle Support

In the Linux kernel, the following vulnerability has been resolved: dm log: fix out-of-bounds write due to region_count overflow The local variable region_count in create_log_context() is declared as unsigned int (32-bit), but dm_sector_div_up() returns sector_t (64-bit). When a device-mapper target has a sufficiently large ti->len with a small region_size, the division result can exceed UINT_MAX. The truncated value is then used to calculate bitset_size, causing clean_bits, sync_bits, and recovering_bits to be allocated far smaller than needed for the actual number of regions. Subsequent log operations (log_set_bit, log_clear_bit, log_test_bit) use region indices derived from the full untruncated region space, causing out-of-bounds writes to kernel heap memory allocated by vmalloc. This can be reproduced by creating a mirror target whose region_count overflows 32 bits: dmsetup create bigzero --table '0 8589934594 zero' dmsetup create mymirror --table '0 8589934594 mirror \ core 2 2 nosync 2 /dev/mapper/bigzero 0 \ /dev/mapper/bigzero 0' The status output confirms the truncation (sync_count=1 instead of 4294967297, because 0x100000001 was truncated to 1): $ dmsetup status mymirror 0 8589934594 mirror 2 254:1 254:1 1/4294967297 ... This leads to a kernel crash in core_in_sync: BUG: scheduling while atomic: (udev-worker)/9150/0x00000000 RIP: 0010:core_in_sync+0x14/0x30 [dm_log] CR2: 0000000000000008 Fixing recursive fault but reboot is needed! Fix by widening the local region_count to sector_t and adding an explicit overflow check before the value is assigned to lc->region_count.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: iommu/riscv: Add IOTINVAL after updating DDT/PDT entries Add riscv_iommu_iodir_iotinval() to perform required TLB and context cache invalidations after updating DDT or PDT entries, as mandated by the RISC-V IOMMU specification (Section 6.3.1 and 6.3.2).

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: drm/msm: Fix VM_BIND UNMAP locking Wrong argument meant that the objs involved in UNMAP ops were not always getting locked. Since _NO_SHARE objs share a common resv with the VM (which is always locked) this would only show up with non-_NO_SHARE BOs. Patchwork: https://patchwork.freedesktop.org/patch/713898/

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Fix clone_alias() to use the original device's devid Currently clone_alias() assumes first argument (pdev) is always the original device pointer. This function is called by pci_for_each_dma_alias() which based on topology decides to send original or alias device details in first argument. This meant that the source devid used to look up and copy the DTE may be incorrect, leading to wrong or stale DTE entries being propagated to alias device. Fix this by passing the original pdev as the opaque data argument to both the direct clone_alias() call and pci_for_each_dma_alias(). Inside clone_alias(), retrieve the original device from data and compute devid from it.

Linux · Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

In the Linux kernel, the following vulnerability has been resolved: quota: Fix race of dquot_scan_active() with quota deactivation dquot_scan_active() can race with quota deactivation in quota_release_workfn() like: CPU0 (quota_release_workfn) CPU1 (dquot_scan_active) ============================== ============================== spin_lock(&dq_list_lock); list_replace_init( &releasing_dquots, &rls_head); /* dquot X on rls_head, dq_count == 0, DQ_ACTIVE_B still set */ spin_unlock(&dq_list_lock); synchronize_srcu(&dquot_srcu); spin_lock(&dq_list_lock); list_for_each_entry(dquot, &inuse_list, dq_inuse) { /* finds dquot X */ dquot_active(X) -> true atomic_inc(&X->dq_count); } spin_unlock(&dq_list_lock); spin_lock(&dq_list_lock); dquot = list_first_entry(&rls_head); WARN_ON_ONCE(atomic_read(&dquot->dq_count)); The problem is not only a cosmetic one as under memory pressure the caller of dquot_scan_active() can end up working on freed dquot. Fix the problem by making sure the dquot is removed from releasing list when we acquire a reference to it.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: soc/tegra: cbb: Fix incorrect ARRAY_SIZE in fabric lookup tables Fix incorrect ARRAY_SIZE usage in fabric lookup tables which could cause out-of-bounds access during target timeout lookup.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: ocfs2: fix listxattr handling when the buffer is full [BUG] If an OCFS2 inode has both inline and block-based xattrs, listxattr() can return a size larger than the caller's buffer when the inline names consume that buffer exactly. kernel BUG at mm/usercopy.c:102! Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI RIP: 0010:usercopy_abort+0xb7/0xd0 mm/usercopy.c:102 Call Trace: __check_heap_object+0xe3/0x120 mm/slub.c:8243 check_heap_object mm/usercopy.c:196 [inline] __check_object_size mm/usercopy.c:250 [inline] __check_object_size+0x5c5/0x780 mm/usercopy.c:215 check_object_size include/linux/ucopysize.h:22 [inline] check_copy_size include/linux/ucopysize.h:59 [inline] copy_to_user include/linux/uaccess.h:219 [inline] listxattr+0xb0/0x170 fs/xattr.c:926 filename_listxattr fs/xattr.c:958 [inline] path_listxattrat+0x137/0x320 fs/xattr.c:988 __do_sys_listxattr fs/xattr.c:1001 [inline] __se_sys_listxattr fs/xattr.c:998 [inline] __x64_sys_listxattr+0x7f/0xd0 fs/xattr.c:998 ... [CAUSE] Commit 936b8834366e ("ocfs2: Refactor xattr list and remove ocfs2_xattr_handler().") replaced the old per-handler list accounting with ocfs2_xattr_list_entry(), but it kept using size == 0 to detect probe mode. That assumption stops being true once ocfs2_listxattr() finishes the inline-xattr pass. If the inline names fill the caller buffer exactly, the block-xattr pass runs with a non-NULL buffer and a remaining size of zero. ocfs2_xattr_list_entry() then skips the bounds check, keeps counting block names, and returns a positive size larger than the supplied buffer. [FIX] Detect probe mode by testing whether the destination buffer pointer is NULL instead of whether the remaining size is zero. That restores the pre-refactor behavior and matches the OCFS2 getxattr helpers. Once the remaining buffer reaches zero while more names are left, the block-xattr pass now returns -ERANGE instead of reporting a size larger than the allocated list buffer.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: ocfs2: validate bg_bits during freefrag scan [BUG] A crafted filesystem can trigger an out-of-bounds bitmap walk when OCFS2_IOC_INFO is issued with OCFS2_INFO_FL_NON_COHERENT. BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] BUG: KASAN: use-after-free in test_bit_le include/asm-generic/bitops/le.h:21 [inline] BUG: KASAN: use-after-free in ocfs2_info_freefrag_scan_chain fs/ocfs2/ioctl.c:495 [inline] BUG: KASAN: use-after-free in ocfs2_info_freefrag_scan_bitmap fs/ocfs2/ioctl.c:588 [inline] BUG: KASAN: use-after-free in ocfs2_info_handle_freefrag fs/ocfs2/ioctl.c:662 [inline] BUG: KASAN: use-after-free in ocfs2_info_handle_request+0x1c66/0x3370 fs/ocfs2/ioctl.c:754 Read of size 8 at addr ffff888031bce000 by task syz.0.636/1435 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xbe/0x130 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xd1/0x650 mm/kasan/report.c:482 kasan_report+0xfb/0x140 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x11c/0x200 mm/kasan/generic.c:200 __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31 instrument_atomic_read include/linux/instrumented.h:68 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] test_bit_le include/asm-generic/bitops/le.h:21 [inline] ocfs2_info_freefrag_scan_chain fs/ocfs2/ioctl.c:495 [inline] ocfs2_info_freefrag_scan_bitmap fs/ocfs2/ioctl.c:588 [inline] ocfs2_info_handle_freefrag fs/ocfs2/ioctl.c:662 [inline] ocfs2_info_handle_request+0x1c66/0x3370 fs/ocfs2/ioctl.c:754 ocfs2_info_handle+0x18d/0x2a0 fs/ocfs2/ioctl.c:828 ocfs2_ioctl+0x632/0x6e0 fs/ocfs2/ioctl.c:913 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:597 [inline] __se_sys_ioctl fs/ioctl.c:583 [inline] __x64_sys_ioctl+0x197/0x1e0 fs/ioctl.c:583 ... [CAUSE] ocfs2_info_freefrag_scan_chain() uses on-disk bg_bits directly as the bitmap scan limit. The coherent path reads group descriptors through ocfs2_read_group_descriptor(), which validates the descriptor before use. The non-coherent path uses ocfs2_read_blocks_sync() instead and skips that validation, so an impossible bg_bits value can drive the bitmap walk past the end of the block. [FIX] Compute the bitmap capacity from the filesystem format with ocfs2_group_bitmap_size(), report descriptors whose bg_bits exceeds that limit, and clamp the scan to the computed capacity. This keeps the freefrag report going while avoiding reads beyond the buffer.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf, arm64: Fix off-by-one in check_imm signed range check check_imm(bits, imm) is used in the arm64 BPF JIT to verify that a branch displacement (in arm64 instruction units) fits into the signed N-bit immediate field of a B, B.cond or CBZ/CBNZ encoding before it is handed to the encoder. The macro currently tests for (imm > 0 && imm >> bits) || (imm < 0 && ~imm >> bits) which admits values in [-2^N, 2^N) — effectively a signed (N+1)-bit range. A signed N-bit field only holds [-2^(N-1), 2^(N-1)), so the check admits one extra bit of range on each side. In particular, for check_imm19(), values in [2^18, 2^19) slip past the check but do not fit into the 19-bit signed imm19 field of B.cond. aarch64_insn_encode_immediate() then masks the raw value into the 19-bit field, setting bit 18 (the sign bit) and flipping a forward branch into a backward one. Same class of issue exists for check_imm26() and the B/BL encoding. Shift by (bits - 1) instead of bits so the actual signed N-bit range is enforced.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Take state lock for af_unix iter When a BPF iterator program updates a sockmap, there is a race condition in unix_stream_bpf_update_proto() where the `peer` pointer can become stale[1] during a state transition TCP_ESTABLISHED -> TCP_CLOSE. CPU0 bpf CPU1 close -------- ---------- // unix_stream_bpf_update_proto() sk_pair = unix_peer(sk) if (unlikely(!sk_pair)) return -EINVAL; // unix_release_sock() skpair = unix_peer(sk); unix_peer(sk) = NULL; sock_put(skpair) sock_hold(sk_pair) // UaF More practically, this fix guarantees that the iterator program is consistently provided with a unix socket that remains stable during iterator execution. [1]: BUG: KASAN: slab-use-after-free in unix_stream_bpf_update_proto+0x155/0x490 Write of size 4 at addr ffff8881178c9a00 by task test_progs/2231 Call Trace: dump_stack_lvl+0x5d/0x80 print_report+0x170/0x4f3 kasan_report+0xe4/0x1c0 kasan_check_range+0x125/0x200 unix_stream_bpf_update_proto+0x155/0x490 sock_map_link+0x71c/0xec0 sock_map_update_common+0xbc/0x600 sock_map_update_elem+0x19a/0x1f0 bpf_prog_bbbf56096cdd4f01_selective_dump_unix+0x20c/0x217 bpf_iter_run_prog+0x21e/0xae0 bpf_iter_unix_seq_show+0x1e0/0x2a0 bpf_seq_read+0x42c/0x10d0 vfs_read+0x171/0xb20 ksys_read+0xff/0x200 do_syscall_64+0xf7/0x5e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Allocated by task 2236: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x63/0x80 kmem_cache_alloc_noprof+0x1d5/0x680 sk_prot_alloc+0x59/0x210 sk_alloc+0x34/0x470 unix_create1+0x86/0x8a0 unix_stream_connect+0x318/0x15b0 __sys_connect+0xfd/0x130 __x64_sys_connect+0x72/0xd0 do_syscall_64+0xf7/0x5e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 2236: kasan_save_stack+0x30/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x70 __kasan_slab_free+0x47/0x70 kmem_cache_free+0x11c/0x590 __sk_destruct+0x432/0x6e0 unix_release_sock+0x9b3/0xf60 unix_release+0x8a/0xf0 __sock_release+0xb0/0x270 sock_close+0x18/0x20 __fput+0x36e/0xac0 fput_close_sync+0xe5/0x1a0 __x64_sys_close+0x7d/0xd0 do_syscall_64+0xf7/0x5e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bpf: Validate node_id in arena_alloc_pages() arena_alloc_pages() accepts a plain int node_id and forwards it through the entire allocation chain without any bounds checking. Validate node_id before passing it down the allocation chain in arena_alloc_pages().

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: NFSD: fix nfs4_file access extra count in nfsd4_add_rdaccess_to_wrdeleg In nfsd4_add_rdaccess_to_wrdeleg, if fp->fi_fds[O_RDONLY] is already set by another thread, __nfs4_file_get_access should not be called to increment the nfs4_file access count since that was already done by the thread that added READ access to the file. The extra fi_access count in nfs4_file can prevent the corresponding nfsd_file from being freed. When stopping nfs-server service, these extra access counts trigger a BUG in kmem_cache_destroy() that shows nfsd_file object remaining on __kmem_cache_shutdown. This problem can be reproduced by running the Git project's test suite over NFS.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: greybus: raw: fix use-after-free on cdev close This addresses a use-after-free bug when a raw bundle is disconnected but its chardev is still opened by an application. When the application releases the cdev, it causes the following panic when init on free is enabled (CONFIG_INIT_ON_FREE_DEFAULT_ON=y): refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 139 at lib/refcount.c:28 refcount_warn_saturate+0xd0/0x130 ... Call Trace: <TASK> cdev_put+0x18/0x30 __fput+0x255/0x2a0 __x64_sys_close+0x3d/0x80 do_syscall_64+0xa4/0x290 entry_SYSCALL_64_after_hwframe+0x77/0x7f The cdev is contained in the "gb_raw" structure, which is freed in the disconnect operation. When the cdev is released at a later time, cdev_put gets an address that points to freed memory. To fix this use-after-free, convert the struct device from a pointer to being embedded, that makes the lifetime of the cdev and of this device the same. Then, use cdev_device_add, which guarantees that the device won't be released until all references to the cdev have been released. Finally, delegate the freeing of the structure to the device release function, instead of freeing immediately in the disconnect callback.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: greybus: raw: fix use-after-free if write is called after disconnect If a user writes to the chardev after disconnect has been called, the kernel panics with the following trace (with CONFIG_INIT_ON_FREE_DEFAULT_ON=y): BUG: kernel NULL pointer dereference, address: 0000000000000218 ... Call Trace: <TASK> gb_operation_create_common+0x61/0x180 gb_operation_create_flags+0x28/0xa0 gb_operation_sync_timeout+0x6f/0x100 raw_write+0x7b/0xc7 [gb_raw] vfs_write+0xcf/0x420 ? task_mm_cid_work+0x136/0x220 ksys_write+0x63/0xe0 do_syscall_64+0xa4/0x290 entry_SYSCALL_64_after_hwframe+0x77/0x7f Disconnect calls gb_connection_destroy, which ends up freeing the connection object. When gb_operation_sync is called in the write file operations, its gets a freed connection as parameter and the kernel panics. The gb_connection_destroy cannot be moved out of the disconnect function, as the Greybus subsystem expect all connections belonging to a bundle to be destroyed when disconnect returns. To prevent this bug, use a rw lock to synchronize access between write and disconnect. This guarantees that the write function doesn't try to use a disconnected connection.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: um: Fix potential race condition in TLB sync During the TLB sync, we need to traverse and modify the page table, so we should hold the page table lock. Since full SMP support for threads within the same process is still missing, let's disable the split page table lock for simplicity.

Linux · Red Hat Enterprise Linux 9 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: crypto: ccp - copy IV using skcipher ivsize AF_ALG rfc3686-ctr-aes-ccp requests pass an 8-byte IV to the driver. ccp_aes_complete() restores AES_BLOCK_SIZE bytes into the caller's IV buffer while RFC3686 skciphers expose an 8-byte IV, so the restore overruns the provided buffer. Use crypto_skcipher_ivsize() to copy only the algorithm's IV length.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net/sched: taprio: fix use-after-free in advance_sched() on schedule switch In advance_sched(), when should_change_schedules() returns true, switch_schedules() is called to promote the admin schedule to oper. switch_schedules() queues the old oper schedule for RCU freeing via call_rcu(), but 'next' still points into an entry of the old oper schedule. The subsequent 'next->end_time = end_time' and rcu_assign_pointer(q->current_entry, next) are use-after-free. Fix this by selecting 'next' from the new oper schedule immediately after switch_schedules(), and using its pre-calculated end_time. setup_first_end_time() sets the first entry's end_time to base_time + interval when the schedule is installed, so the value is already correct. The deleted 'end_time = sched_base_time(admin)' assignment was also harmful independently: it would overwrite the new first entry's pre-calculated end_time with just base_time.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 6

In the Linux kernel, the following vulnerability has been resolved: ice: fix double-free of tx_buf skb If ice_tso() or ice_tx_csum() fail, the error path in ice_xmit_frame_ring() frees the skb, but the 'first' tx_buf still points to it and is marked as valid (ICE_TX_BUF_SKB). 'next_to_use' remains unchanged, so the potential problem will likely fix itself when the next packet is transmitted and the tx_buf gets overwritten. But if there is no next packet and the interface is brought down instead, ice_clean_tx_ring() -> ice_unmap_and_free_tx_buf() will find the tx_buf and free the skb for the second time. The fix is to reset the tx_buf type to ICE_TX_BUF_EMPTY in the error path, so that ice_unmap_and_free_tx_buf(). Move the initialization of 'first' up, to ensure it's already valid in case we hit the linearization error path. The bug was spotted by AI while I had it looking for something else. It also proposed an initial version of the patch. I reproduced the bug and tested the fix by adding code to inject failures, on a build with KASAN. I looked for similar bugs in related Intel drivers and did not find any.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: af_unix: Drop all SCM attributes for SOCKMAP. SOCKMAP can hide inflight fd from AF_UNIX GC. When a socket in SOCKMAP receives skb with inflight fd, sk_psock_verdict_data_ready() looks up the mapped socket and enqueue skb to its psock->ingress_skb. Since neither the old nor the new GC can inspect the psock queue, the hidden skb leaks the inflight sockets. Note that this cannot be detected via kmemleak because inflight sockets are linked to a global list. In addition, SOCKMAP redirect breaks the Tarjan-based GC's assumption that unix_edge.successor is always alive, which is no longer true once skb is redirected, resulting in use-after-free below. [0] Moreover, SOCKMAP does not call scm_stat_del() properly, so unix_show_fdinfo() could report an incorrect fd count. sk_msg_recvmsg() does not support any SCM attributes in the first place. Let's drop all SCM attributes before passing skb to the SOCKMAP layer. [0]: BUG: KASAN: slab-use-after-free in unix_del_edges (net/unix/garbage.c:118 net/unix/garbage.c:181 net/unix/garbage.c:251) Read of size 8 at addr ffff888125362670 by task kworker/56:1/496 CPU: 56 UID: 0 PID: 496 Comm: kworker/56:1 Not tainted 7.0.0-rc7-00263-gb9d8b856689d #3 PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 Workqueue: events sk_psock_backlog Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:122) print_report (mm/kasan/report.c:379) kasan_report (mm/kasan/report.c:597) unix_del_edges (net/unix/garbage.c:118 net/unix/garbage.c:181 net/unix/garbage.c:251) unix_destroy_fpl (net/unix/garbage.c:317) unix_destruct_scm (./include/net/scm.h:80 ./include/net/scm.h:86 net/unix/af_unix.c:1976) sk_psock_backlog (./include/linux/skbuff.h:?) process_scheduled_works (kernel/workqueue.c:?) worker_thread (kernel/workqueue.c:?) kthread (kernel/kthread.c:438) ret_from_fork (arch/x86/kernel/process.c:164) ret_from_fork_asm (arch/x86/entry/entry_64.S:258) </TASK> Allocated by task 955: kasan_save_track (mm/kasan/common.c:58 mm/kasan/common.c:78) __kasan_slab_alloc (mm/kasan/common.c:369) kmem_cache_alloc_noprof (mm/slub.c:4539) sk_prot_alloc (net/core/sock.c:2240) sk_alloc (net/core/sock.c:2301) unix_create1 (net/unix/af_unix.c:1099) unix_create (net/unix/af_unix.c:1169) __sock_create (net/socket.c:1606) __sys_socketpair (net/socket.c:1811) __x64_sys_socketpair (net/socket.c:1863 net/socket.c:1860 net/socket.c:1860) do_syscall_64 (arch/x86/entry/syscall_64.c:?) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Freed by task 496: kasan_save_track (mm/kasan/common.c:58 mm/kasan/common.c:78) kasan_save_free_info (mm/kasan/generic.c:587) __kasan_slab_free (mm/kasan/common.c:287) kmem_cache_free (mm/slub.c:6165) __sk_destruct (net/core/sock.c:2282 net/core/sock.c:2384) sk_psock_destroy (./include/net/sock.h:?) process_scheduled_works (kernel/workqueue.c:?) worker_thread (kernel/workqueue.c:?) kthread (kernel/kthread.c:438) ret_from_fork (arch/x86/kernel/process.c:164) ret_from_fork_asm (arch/x86/entry/entry_64.S:258)

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: sctp: fix OOB write to userspace in sctp_getsockopt_peer_auth_chunks sctp_getsockopt_peer_auth_chunks() checks that the caller's optval buffer is large enough for the peer AUTH chunk list with if (len < num_chunks) return -EINVAL; but then writes num_chunks bytes to p->gauth_chunks, which lives at offset offsetof(struct sctp_authchunks, gauth_chunks) == 8 inside optval. The check is missing the sizeof(struct sctp_authchunks) = 8-byte header. When the caller supplies len == num_chunks (for any num_chunks > 0) the test passes but copy_to_user() writes sizeof(struct sctp_authchunks) = 8 bytes past the declared buffer. The sibling function sctp_getsockopt_local_auth_chunks() at the next line already has the correct check: if (len < sizeof(struct sctp_authchunks) + num_chunks) return -EINVAL; Align the peer variant with its sibling. Reproducer confirms on v7.0-13-generic: an unprivileged userspace caller that opens a loopback SCTP association with AUTH enabled, queries num_chunks with a short optval, then issues the real getsockopt with len == num_chunks and sentinel bytes painted past the buffer observes those sentinel bytes overwritten with the peer's AUTH chunk type. The bytes written are under the peer's control but land in the caller's own userspace; this is not a kernel memory corruption, but it is a kernel-side contract violation that can silently corrupt adjacent userspace data.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: pppoe: drop PFC frames RFC 2516 Section 7 states that Protocol Field Compression (PFC) is NOT RECOMMENDED for PPPoE. In practice, pppd does not support negotiating PFC for PPPoE sessions, and the current PPPoE driver assumes an uncompressed (2-byte) protocol field. However, the generic PPP layer function ppp_input() is not aware of the negotiation result, and still accepts PFC frames. If a peer with a broken implementation or an attacker sends a frame with a compressed (1-byte) protocol field, the subsequent PPP payload is shifted by one byte. This causes the network header to be 4-byte misaligned, which may trigger unaligned access exceptions on some architectures. To reduce the attack surface, drop PPPoE PFC frames. Introduce ppp_skb_is_compressed_proto() helper function to be used in both ppp_generic.c and pppoe.c to avoid open-coding.

Linux · Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat Enterprise Linux 9 · Red Hat Enterprise Linux 9.6 Extended Update Support

In the Linux kernel, the following vulnerability has been resolved: netfilter: nat: use kfree_rcu to release ops Florian Westphal says: "Historically this is not an issue, even for normal base hooks: the data path doesn't use the original nf_hook_ops that are used to register the callbacks. However, in v5.14 I added the ability to dump the active netfilter hooks from userspace. This code will peek back into the nf_hook_ops that are available at the tail of the pointer-array blob used by the datapath. The nat hooks are special, because they are called indirectly from the central nat dispatcher hook. They are currently invisible to the nfnl hook dump subsystem though. But once that changes the nat ops structures have to be deferred too." Update nf_nat_register_fn() to deal with partial exposition of the hooks from error path which can be also an issue for nfnetlink_hook.

Linux · Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_osf: fix potential NULL dereference in ttl check The nf_osf_ttl() function accessed skb->dev to perform a local interface address lookup without verifying that the device pointer was valid. Additionally, the implementation utilized an in_dev_for_each_ifa_rcu loop to match the packet source address against local interface addresses. It assumed that packets from the same subnet should not see a decrement on the initial TTL. A packet might appear it is from the same subnet but it actually isn't especially in modern environments with containers and virtual switching. Remove the device dereference and interface loop. Replace the logic with a switch statement that evaluates the TTL according to the ttl_check.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: fs/adfs: validate nzones in adfs_validate_bblk() Reject ADFS disc records with a zero zone count during boot block validation, before the disc record is used. When nzones is 0, adfs_read_map() passes it to kmalloc_array(0, ...) which returns ZERO_SIZE_PTR, and adfs_map_layout() then writes to dm[-1], causing an out-of-bounds write before the allocated buffer. adfs_validate_dr0() already rejects nzones != 1 for old-format images. Add the equivalent check to adfs_validate_bblk() for new-format images so that a crafted image with nzones == 0 is rejected at probe time. Found by syzkaller.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: sched/psi: fix race between file release and pressure write A potential race condition exists between pressure write and cgroup file release regarding the priv member of struct kernfs_open_file, which triggers the uaf reported in [1]. Consider the following scenario involving execution on two separate CPUs: CPU0 CPU1 ==== ==== vfs_rmdir() kernfs_iop_rmdir() cgroup_rmdir() cgroup_kn_lock_live() cgroup_destroy_locked() cgroup_addrm_files() cgroup_rm_file() kernfs_remove_by_name() kernfs_remove_by_name_ns() vfs_write() __kernfs_remove() new_sync_write() kernfs_drain() kernfs_fop_write_iter() kernfs_drain_open_files() cgroup_file_write() kernfs_release_file() pressure_write() cgroup_file_release() ctx = of->priv; kfree(ctx); of->priv = NULL; cgroup_kn_unlock() cgroup_kn_lock_live() cgroup_get(cgrp) cgroup_kn_unlock() if (ctx->psi.trigger) // here, trigger uaf for ctx, that is of->priv The cgroup_rmdir() is protected by the cgroup_mutex, it also safeguards the memory deallocation of of->priv performed within cgroup_file_release(). However, the operations involving of->priv executed within pressure_write() are not entirely covered by the protection of cgroup_mutex. Consequently, if the code in pressure_write(), specifically the section handling the ctx variable executes after cgroup_file_release() has completed, a uaf vulnerability involving of->priv is triggered. Therefore, the issue can be resolved by extending the scope of the cgroup_mutex lock within pressure_write() to encompass all code paths involving of->priv, thereby properly synchronizing the race condition occurring between cgroup_file_release() and pressure_write(). And, if an live kn lock can be successfully acquired while executing the pressure write operation, it indicates that the cgroup deletion process has not yet reached its final stage; consequently, the priv pointer within open_file cannot be NULL. Therefore, the operation to retrieve the ctx value must be moved to a point *after* the live kn lock has been successfully acquired. In another situation, specifically after entering cgroup_kn_lock_live() but before acquiring cgroup_mutex, there exists a different class of race condition: CPU0: write memory.pressure CPU1: write cgroup.pressure=0 =========================== ============================= kernfs_fop_write_iter() kernfs_get_active_of(of) pressure_write() cgroup_kn_lock_live(memory.pressure) cgroup_tryget(cgrp) kernfs_break_active_protection(kn) ... blocks on cgroup_mutex cgroup_pressure_write() cgroup_kn_lock_live(cgroup.pressure) cgroup_file_show(memory.pressure, false) kernfs_show(false) kernfs_drain_open_files() cgroup_file_release(of) kfree(ctx) of->priv = NULL cgroup_kn_unlock() ... acquires cgroup_mutex ctx = of->priv; // may now be NULL if (ctx->psi.trigger) // NULL dereference Consequently, there is a possibility that of->priv is NULL, the pressure write needs to check for this. Now that the scope of the cgroup_mutex has been expanded, the original explicit cgroup_get/put operations are no longer necessary, this is because acquiring/releasing the live kn lock inherently executes a cgroup get/put operation. [1] BUG: KASAN: slab-use-after-free in pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011 Call Trace: pressure_write+0xa4/0x210 kernel/cgroup/cgroup.c:4011 cgroup_file_write+0x36f/0x790 kernel/cgroup/cgroup.c:43 ---truncated---

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: join hook list via splice_list_rcu() in commit phase Publish new hooks in the list into the basechain/flowtable using splice_list_rcu() to ensure netlink dump list traversal via rcu is safe while concurrent ruleset update is going on.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: avoid double drm_exec_fini() in userq validate When new_addition is true, amdgpu_userq_vm_validate() calls drm_exec_fini(&exec) before iterating over the collected HMM ranges and calling amdgpu_ttm_tt_get_user_pages(). If amdgpu_ttm_tt_get_user_pages() fails in that path, the code jumps to unlock_all and calls drm_exec_fini(&exec) a second time on the same exec object. drm_exec_fini() is not idempotent: it frees exec->objects and may also drop exec->contended and finalize the ww acquire context. Route that error path directly to the range cleanup once exec has already been finalized. Issue found using a prototype static analysis tool and confirmed by code review. (cherry picked from commit 2802952e4a07306da6ebe813ff1acacc5691851a)

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net: airoha: fix BQL imbalance in TX path Fix a possible BQL imbalance in airoha_dev_xmit(), where inflight packets are accounted only for the AIROHA_NUM_TX_RING netdev TX queues. The queue index is computed as: qid = skb_get_queue_mapping(skb) % ARRAY_SIZE(qdma->q_tx) txq = netdev_get_tx_queue(dev, qid); However, airoha_qdma_tx_napi_poll() accounts completions across all netdev TX queues (num_tx_queues), leading to inconsistent BQL accounting. Also reset all netdev TX queues in the ndo_stop callback.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: neigh: let neigh_xmit take skb ownership neigh_xmit always releases the skb, except when no neighbour table is found. But even the first added user of neigh_xmit (mpls) relied on neigh_xmit to release the skb (or queue it for tx). sashiko reported: If neigh_xmit() is called with an uninitialized neighbor table (for example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT and bypasses its internal out_kfree_skb error path. Because the return value of neigh_xmit() is ignored here, does this leak the SKB? Assume full ownership and remove the last code path that doesn't xmit or free skb.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 9 · Red Hat Enterprise Linux 6

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Fix error cleanup in xe_exec_queue_create_ioctl() Two error handling issues exist in xe_exec_queue_create_ioctl(): 1. When xe_hw_engine_group_add_exec_queue() fails, the error path jumps to put_exec_queue which skips xe_exec_queue_kill(). If the VM is in preempt fence mode, xe_vm_add_compute_exec_queue() has already added the queue to the VM's compute exec queue list. Skipping the kill leaves the queue on that list, leading to a dangling pointer after the queue is freed. 2. When xa_alloc() fails after xe_hw_engine_group_add_exec_queue() has succeeded, the error path does not call xe_hw_engine_group_del_exec_queue() to remove the queue from the hw engine group list. The queue is then freed while still linked into the hw engine group, causing a use-after-free. Fix both by: - Changing the xe_hw_engine_group_add_exec_queue() failure path to jump to kill_exec_queue so that xe_exec_queue_kill() properly removes the queue from the VM's compute list. - Adding a del_hw_engine_group label before kill_exec_queue for the xa_alloc() failure path, which removes the queue from the hw engine group before proceeding with the rest of the cleanup. (cherry picked from commit 37c831f401746a45d510b312b0ed7a77b1e06ec8)

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: bonding: 3ad: implement proper RCU rules for port->aggregator syzbot found a data-race in bond_3ad_get_active_agg_info / bond_3ad_state_machine_handler [1] which hints at lack of proper RCU implementation. Add __rcu qualifier to port->aggregator, and add proper RCU API. [1] BUG: KCSAN: data-race in bond_3ad_get_active_agg_info / bond_3ad_state_machine_handler write to 0xffff88813cf5c4b0 of 8 bytes by task 36 on cpu 0: ad_port_selection_logic drivers/net/bonding/bond_3ad.c:1659 [inline] bond_3ad_state_machine_handler+0x9d5/0x2d60 drivers/net/bonding/bond_3ad.c:2569 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0x4f0/0x9c0 kernel/workqueue.c:3385 worker_thread+0x58a/0x780 kernel/workqueue.c:3466 kthread+0x22a/0x280 kernel/kthread.c:436 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read to 0xffff88813cf5c4b0 of 8 bytes by task 22063 on cpu 1: __bond_3ad_get_active_agg_info drivers/net/bonding/bond_3ad.c:2858 [inline] bond_3ad_get_active_agg_info+0x8c/0x230 drivers/net/bonding/bond_3ad.c:2881 bond_fill_info+0xe0f/0x10f0 drivers/net/bonding/bond_netlink.c:853 rtnl_link_info_fill net/core/rtnetlink.c:906 [inline] rtnl_link_fill+0x1d7/0x4e0 net/core/rtnetlink.c:927 rtnl_fill_ifinfo+0xf8e/0x1380 net/core/rtnetlink.c:2168 rtmsg_ifinfo_build_skb+0x11c/0x1b0 net/core/rtnetlink.c:4453 rtmsg_ifinfo_event net/core/rtnetlink.c:4486 [inline] rtmsg_ifinfo+0x6d/0x110 net/core/rtnetlink.c:4495 __dev_notify_flags+0x76/0x390 net/core/dev.c:9790 netif_change_flags+0xac/0xd0 net/core/dev.c:9823 do_setlink+0x905/0x2950 net/core/rtnetlink.c:3180 rtnl_group_changelink net/core/rtnetlink.c:3813 [inline] __rtnl_newlink net/core/rtnetlink.c:3981 [inline] rtnl_newlink+0xf55/0x1400 net/core/rtnetlink.c:4109 rtnetlink_rcv_msg+0x64b/0x720 net/core/rtnetlink.c:6995 netlink_rcv_skb+0x123/0x220 net/netlink/af_netlink.c:2550 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:7022 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x5a8/0x680 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x5c8/0x6f0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg net/socket.c:802 [inline] ____sys_sendmsg+0x563/0x5b0 net/socket.c:2698 ___sys_sendmsg+0x195/0x1e0 net/socket.c:2752 __sys_sendmsg net/socket.c:2784 [inline] __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __x64_sys_sendmsg+0xd4/0x160 net/socket.c:2787 x64_sys_call+0x194c/0x3020 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000000 -> 0xffff88813cf5c400 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 22063 Comm: syz.0.31122 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net: tls: fix strparser anchor skb leak on offload RX setup failure When tls_set_device_offload_rx() fails at tls_dev_add(), the error path calls tls_sw_free_resources_rx() to clean up the SW context that was initialized by tls_set_sw_offload(). This function calls tls_sw_release_resources_rx() (which stops the strparser via tls_strp_stop()) and tls_sw_free_ctx_rx() (which kfrees the context), but never frees the anchor skb that was allocated by alloc_skb(0) in tls_strp_init(). Note that tls_sw_free_resources_rx() is exclusively used for this "failed to start offload" code path, there's no other caller. The leak did not exist before commit 84c61fe1a75b ("tls: rx: do not use the standard strparser"), because the standard strparser doesn't try to pre-allocate an skb. The normal close path in tls_sk_proto_close() handles cleanup by calling tls_sw_strparser_done() (which calls tls_strp_done()) after dropping the socket lock, because tls_strp_done() does cancel_work_sync() and the strparser work handler takes the socket lock.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 9 · Red Hat Enterprise Linux 6

In the Linux kernel, the following vulnerability has been resolved: futex: Drop CLONE_THREAD requirement for private default hash alloc Currently need_futex_hash_allocate_default() depends on strict pthread semantics, abusing CLONE_THREAD. This breaks the non-concurrency assumptions when doing the mm->futex_ref pcpu allocations, leading to bugs[0] when sharing the mm in other ways; ie: BUG: KASAN: slab-use-after-free in futex_hash_put ... where the +1 bias can end up on a percpu counter that mm->futex_ref no longer points at. Loosen the check to cover any CLONE_VM clone, except vfork(). Excluding vfork keeps the existing paths untouched (no overhead), and we can't race in the first place: either the parent is suspended and the child runs alone, or mm->futex_ref is already allocated from an earlier CLONE_VM.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net: ena: PHC: Fix potential use-after-free in get_timestamp Move the phc->active check and resp pointer assignment to after acquiring the spinlock. Previously, phc->active was checked without holding the lock, and resp was cached from ena_dev->phc.virt_addr before the lock was acquired. If ena_com_phc_destroy() runs between the lockless active check and the lock acquisition, it sets active=false, releases the lock, frees the DMA memory, and sets virt_addr=NULL. The get_timestamp path would then read a NULL virt_addr and dereference it. With both the active check and the pointer read under the lock, destroy cannot free the memory while get_timestamp is using it.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: KVM: Reject wrapped offset in kvm_reset_dirty_gfn() kvm_reset_dirty_gfn() guards the gfn range with if (!memslot || (offset + __fls(mask)) >= memslot->npages) return; but offset is u64 and the addition is unchecked. The check can be silently bypassed by a u64 wrap. The dirty ring backing those entries is MAP_SHARED at KVM_DIRTY_LOG_PAGE_OFFSET of the vcpu fd, so the VMM can rewrite the slot and offset fields of any entry between when the kernel pushes them and when KVM_RESET_DIRTY_RINGS consumes them. On reset, kvm_dirty_ring_reset() re-reads the values via READ_ONCE() and feeds them straight back into this check; only the flags handshake is treated as the handover, the slot/offset payload is taken on trust. Crafting two entries entry[i].offset = 0xffffffffffffffc1 entry[i+1].offset = 0 makes the coalescing loop in kvm_dirty_ring_reset() compute delta = (s64)(0 - 0xffffffffffffffc1) = 63 which falls in [0, BITS_PER_LONG), so it folds entry[i+1] into the existing mask by setting bit 63. The trailing kvm_reset_dirty_gfn() call then sees offset = 0xffffffffffffffc1 and __fls(mask) = 63; the sum is 0 in u64 and the bounds check passes. That offset propagates into kvm_arch_mmu_enable_log_dirty_pt_masked() unchanged. On the legacy MMU path -- kvm_memslots_have_rmaps() == true, i.e. shadow paging, any VM that has allocated shadow roots, or a write-tracked slot -- it reaches gfn_to_rmap(), which indexes slot->arch.rmap[0][] with a near-U64_MAX gfn. That is an out-of-bounds load of a kvm_rmap_head, followed by a conditional clear of PT_WRITABLE_MASK in whatever the loaded pointer points at. The path is reachable from any process holding /dev/kvm. Range-check offset on its own first, so the addition cannot wrap. memslot->npages is bounded well below U64_MAX, so once offset < npages holds, offset + __fls(mask) (with __fls(mask) < BITS_PER_LONG) stays in range.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: fix GAIT table indexing due to double-scaling pointer arithmetic kvm_s390_pci_aif_enable(), kvm_s390_pci_aif_disable(), and aen_host_forward() index the GAIT by manually multiplying the index with sizeof(struct zpci_gaite). Since aift->gait is already a struct zpci_gaite pointer, this double-scales the offset, accessing element aisb*16 instead of aisb. This causes out-of-bounds accesses when aisb >= 32 (with ZPCI_NR_DEVICES=512) Fix by removing the erroneous sizeof multiplication.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix possible infinite loop and oob read in symlink_data() On 32-bit architectures, the infinite loop is as follows: len = p->ErrorDataLength == 0xfffffff8 u8 *next = p->ErrorContextData + len next == p On 32-bit architectures, the out-of-bounds read is as follows: len = p->ErrorDataLength == 0xfffffff0 u8 *next = p->ErrorContextData + len next == (u8 *)p - 8

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: ceph: fix a buffer leak in __ceph_setxattr() The old_blob in __ceph_setxattr() can store ci->i_xattrs.prealloc_blob value during the retry. However, it is never called the ceph_buffer_put() for the old_blob object. This patch fixes the issue of the buffer leak.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: ceph: put folios not suitable for writeback The batch holds references to the folios (see `filemap_get_folios`, `folio_batch_release`), so we need to `folio_put` the folios we remove. Tested on v6.18.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: virt: sev-guest: Do not use host-controlled page order in cleanup path When issuing an extended guest request (SVM_VMGEXIT_EXT_GUEST_REQUEST), get_ext_report() allocates a buffer to retrieve a certificate blob from the host, keeping track of its size in report_req->certs_len. However, the host may return SNP_GUEST_VMM_ERR_INVALID_LEN, indicating an invalid buffer size, as well as the expected length of such buffer. get_ext_report() subsequently updates report_req->certs_len with the host-controlled value, and cleans up the buffer by computing a page order from such value. This is incorrect, as the host-provided length may not match the page order of the original allocation, potentially resulting in corruption in the page allocator. Fix this by using alloc_pages_exact() instead, and reusing @npages to compute the size passed to free_pages_exact(). For consistency, also use @npages to compute the size when allocating the pages, even though this last change has no functional effect.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential null-ptr-deref in decode_choose_args() A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself contains a CRUSH map. When decoding this CRUSH map in crush_decode(), an array of max_buckets CRUSH buckets is decoded, where some indices may not refer to actual buckets and are therefore set to NULL. The received CRUSH map may optionally contain choose_args that get decoded in decode_choose_args(). When decoding a crush_choose_arg_map, a series of choose_args for different buckets is decoded, with the bucket_index being read from the incoming message. It is only checked that the bucket index does not exceed max_buckets, but not that it doesn't point to an index with a NULL bucket. If a (potentially corrupted) message contains a crush_choose_arg_map including such a bucket_index, a null pointer dereference may occur in the subsequent processing when attempting to access the bucket with the given index. This patch fixes the issue by extending the affected check. Now, it is only attempted to access the bucket if it is not NULL.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix potential out-of-bounds access in __ceph_x_decrypt() In __ceph_x_decrypt(), a part of the buffer p is interpreted as a ceph_x_encrypt_header, and the magic field of this struct is accessed. This happens without any guarantee that the buffer is large enough to hold this struct. The function parameter ciphertext_len represents the length of the ciphertext to decrypt and is guaranteed to be at most the remaining size of the allocated buffer p. However, this value is not necessarily greater than sizeof(ceph_x_encrypt_header). E.g., a message frame of type FRAME_TAG_AUTH_REPLY_MORE, that is just as long to hold the ciphertext at its end with a ciphertext_len of 8 or less, can trigger an out-of-bounds memory access when accessing hdr->magic. This patch fixes the issue by adding a check to ensure that the decrypted plaintext in the buffer is large enough to represent at least the ceph_x_encrypt_header.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: libceph: handle rbtree insertion error in decode_choose_args() A message of type CEPH_MSG_OSD_MAP contains an OSD map that itself contains a CRUSH map. The received CRUSH map may optionally contain choose_args that get decoded in decode_choose_args(). In this function, num_choose_arg_maps is read from the message, and a corresponding number of crush_choose_arg_maps gets decoded afterwards. Each crush_choose_arg_map has a choose_args_index, which serves as the key when inserting it into the choose_args rbtree of the decoded crush_map. If a (potentially corrupted) message contains two crush_choose_arg_maps with the same index, the assertion in insert_choose_arg_map() triggers a kernel BUG when trying to insert the second crush_choose_arg_map. This patch fixes the issue by switching to the non-asserting rbtree insertion function and rejecting the message if the insertion fails. [ idryomov: changelog ]

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Fix oops due to out of scope access Below oops triggers when kill QEMU process: Oops: general protection fault, probably for non-canonical address 0x7fffffff844eaaa7: 0000 [#1] SMP NOPTI Call Trace: <TASK> do_raw_spin_lock+0xaa/0xc0 _raw_spin_lock_irqsave+0x21/0x40 domain_remove_dev_pasid+0x52/0x160 intel_nested_set_dev_pasid+0x1b9/0x1e0 __iommu_set_group_pasid+0x56/0x120 pci_dev_reset_iommu_done+0xe3/0x180 pcie_flr+0x65/0x160 __pci_reset_function_locked+0x5b/0x120 vfio_pci_core_close_device+0x63/0xe0 [vfio_pci_core] vfio_df_close+0x4f/0xa0 vfio_df_unbind_iommufd+0x2d/0x60 vfio_device_fops_release+0x3e/0x40 __fput+0xe5/0x2c0 task_work_run+0x58/0xa0 do_exit+0x2c8/0x600 do_group_exit+0x2f/0xa0 get_signal+0x863/0x8c0 arch_do_signal_or_restart+0x24/0x100 exit_to_user_mode_loop+0x87/0x380 do_syscall_64+0x2ff/0x11e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The global static blocked domain is a dummy domain without corresponding dmar_domain structure, accessing beyond iommu_domain structure triggers oops easily. Fix it by return early in domain_remove_dev_pasid() like identity domain.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: iommu: Fix WARN_ON in __iommu_group_set_domain_nofail() due to reset In __iommu_group_set_domain_internal(), concurrent domain attachments are rejected when any device in the group is recovering. This is necessary to fence concurrent attachments to a multi-device group where devices might share the same RID due to PCI DMA alias quirks, but triggers the WARN_ON in __iommu_group_set_domain_nofail(). Other IOMMU_SET_DOMAIN_MUST_SUCCEED callers in detach/teardown paths, such as __iommu_group_set_core_domain and __iommu_release_dma_ownership, should not be rejected, as the domain would be freed anyway in these nofail paths while group->domain is still pointing to it. So pci_dev_reset_iommu_done() could trigger a UAF when re-attaching group->domain. Honor the IOMMU_SET_DOMAIN_MUST_SUCCEED flag, allowing the callers through the group->recovery_cnt fence, so as to update the group->domain pointer. Instead add a gdev->blocked check in the device iteration loop, to prevent any concurrent per-device detachment.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: drm/xe/dma-buf: handle empty bo and UAF races There look to be some nasty races here when triggering the invalidate_mappings hook: 1) We do xe_bo_alloc() followed by the attach, before the actual full bo init step in xe_dma_buf_init_obj(). However the bo is visible on the attachments list after the attach. This is bad since exporter driver, say amdgpu, can at any time call back into our invalidate_mappings hook, with an empty/bogus bo, leading to potential bugs/crashes. 2) Similar to 1) but here we get a UAF, when the invalidate_mappings hook is triggered. For example, we get as far as xe_bo_init_locked() but this fails in some way. But here the bo will be freed on error, but we still have it attached from dma-buf pov, so if the invalidate_mappings is now triggered then the bo we access is gone and we trigger UAF and more bugs/crashes. To fix this, move the attach step until after we actually have a fully set up buffer object. Note that the bo is not published to userspace until later, so not sure what the comment "Don't publish the bo until we have a valid attachment", is referring to. We have at least two different customers reporting hitting a NULL ptr deref in evict_flags when importing something from amdgpu, followed by triggering the evict flow. Hit rate is also pretty low, which would hint at some kind of race, so something like 1) or 2) might explain this. v2: - Shuffle the order of the ops slightly (no functional change) - Improve the comment to better explain the ordering (Matt B) (cherry picked from commit af1f2ad0c59fe4e2f924c526f66e968289d77971)

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 9 · Red Hat Enterprise Linux 6

In the Linux kernel, the following vulnerability has been resolved: drm/xe/dma-buf: fix UAF with retry loop Retry doesn't work here, since bo will be freed on error, leading to UAF. However, now that we do the alloc & init before the attach, we can now combine this as one unit and have the init do the alloc for us. This should make the retry safe. Reported by Sashiko. v2: Fix up the error unwind (CI) (cherry picked from commit 479669418253e0f27f8cf5db01a731352ea592e7)

Linux · Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: net: qrtr: fix refcount saturation and potential UAF in qrtr_port_remove In qrtr_port_remove(), the socket reference count is decremented via __sock_put() before the port is removed from the qrtr_ports XArray and before the RCU grace period elapses. This breaks the fundamental RCU update paradigm. It exposes a race window where a concurrent RCU reader (such as qrtr_reset_ports() or qrtr_port_lookup()) can obtain a pointer to the socket from the XArray, and attempt to call sock_hold() on a socket whose reference count has already dropped to zero. This exact race condition was hit during syzkaller fuzzing, leading to the following refcount saturation warning and a potential Use-After-Free: refcount_t: saturated; leaking memory. WARNING: CPU: 3 PID: 1273 at lib/refcount.c:22 refcount_warn_saturate+0xae/0x1d0 Modules linked in: qrtr(+) bochs drm_shmem_helper ... Call Trace: <TASK> qrtr_reset_ports net/qrtr/af_qrtr.c:768 [inline] [qrtr] __qrtr_bind.isra.0+0x48b/0x570 net/qrtr/af_qrtr.c:805 [qrtr] qrtr_bind+0x17d/0x210 net/qrtr/af_qrtr.c:901 [qrtr] kernel_bind+0xe4/0x120 net/socket.c:3592 qrtr_ns_init+0x1a6/0x380 net/qrtr/ns.c:715 [qrtr] qrtr_proto_init+0x3b/0xff0 net/qrtr/af_qrtr.c:169 [qrtr] do_one_initcall+0xf5/0x5e0 init/main.c:1283 ... </TASK> Fix this by deferring the reference count decrement until after the xa_erase() and the synchronize_rcu() complete. (Note: The v1 of this patch incorrectly replaced __sock_put() with sock_put(). As Simon Horman pointed out, the callers of qrtr_port_remove() still hold a reference to the socket, so freeing the socket memory here would lead to a subsequent UAF in the caller. Thus, the __sock_put() is kept, but only repositioned to close the RCU race.)

Linux · Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem

In the Linux kernel, the following vulnerability has been resolved: fs/fcntl: fix SOFTIRQ-unsafe lock order in fasync signaling A SOFTIRQ-safe to SOFTIRQ-unsafe lock order deadlock can occur in send_sigio() and send_sigurg() when a process group receives a signal. When FASYNC is configured for a process group (PIDTYPE_PGID), both functions use read_lock(&tasklist_lock) to traverse the task list. However, they are frequently called from softirq context: - send_sigio() via input_inject_event -> kill_fasync - send_sigurg() via tcp_check_urg -> sk_send_sigurg (NET_RX_SOFTIRQ) The deadlock is caused by the rwlock writer fairness mechanism: 1. CPU 0 (process context) holds read_lock(&tasklist_lock) in do_wait(). 2. CPU 1 (process context) attempts write_lock(&tasklist_lock) in fork() or exit() and spins, which blocks all new readers. 3. CPU 0 is interrupted by a softirq (e.g., TCP URG packet reception). 4. The softirq calls send_sigurg() and attempts to acquire read_lock(&tasklist_lock), deadlocking because CPU 1 is waiting. Since PID hashing and do_each_pid_task() traversals are already RCU-protected, the read_lock on tasklist_lock is no longer strictly required for safe traversal. Fix this by replacing tasklist_lock with rcu_read_lock(), aligning the process group signaling path with the single-PID path. This also mitigates a potential remote denial of service vector via TCP URG packets. Lockdep splat: ===================================================== WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected [...] Chain exists of: &dev->event_lock --> &f_owner->lock --> tasklist_lock Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(tasklist_lock); local_irq_disable(); lock(&dev->event_lock); lock(&f_owner->lock); <Interrupt> lock(&dev->event_lock); *** DEADLOCK ***

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: Revert "wireguard: device: enable threaded NAPI" This reverts commit 933466fc50a8e4eb167acbd0d8ec96a078462e9c which is commit db9ae3b6b43c79b1ba87eea849fd65efa05b4b2e upstream. We have had three independent production user reports in combination with Cilium utilizing WireGuard as encryption underneath that k8s Pod E/W traffic to certain peer nodes fully stalled. The situation appears as follows: - Occurs very rarely but at random times under heavy networking load. - Once the issue triggers the decryption side stops working completely for that WireGuard peer, other peers keep working fine. The stall happens also for newly initiated connections towards that particular WireGuard peer. - Only the decryption side is affected, never the encryption side. - Once it triggers, it never recovers and remains in this state, the CPU/mem on that node looks normal, no leak, busy loop or crash. - bpftrace on the affected system shows that wg_prev_queue_enqueue fails, thus the MAX_QUEUED_PACKETS (1024 skbs!) for the peer's rx_queue is reached. - Also, bpftrace shows that wg_packet_rx_poll for that peer is never called again after reaching this state for that peer. For other peers wg_packet_rx_poll does get called normally. - Commit db9ae3b ("wireguard: device: enable threaded NAPI") switched WireGuard to threaded NAPI by default. The default has not been changed for triggering the issue, neither did CPU hotplugging occur (i.e. 5bd8de2 ("wireguard: queueing: always return valid online CPU in wg_cpumask_choose_online()")). - The issue has been observed with stable kernels of v5.15 as well as v6.1. It was reported to us that v5.10 stable is working fine, and no report on v6.6 stable either (somewhat related discussion in [0] though). - In the WireGuard driver the only material difference between v5.10 stable and v5.15 stable is the switch to threaded NAPI by default. [0] https://lore.kernel.org/netdev/CA+wXwBTT74RErDGAnj98PqS=wvdh8eM1pi4q6tTdExtjnokKqA@mail.gmail.com/ Breakdown of the problem: 1) skbs arriving for decryption are enqueued to the peer->rx_queue in wg_packet_consume_data via wg_queue_enqueue_per_device_and_peer. 2) The latter only moves the skb into the MPSC peer queue if it does not surpass MAX_QUEUED_PACKETS (1024) which is kept track in an atomic counter via wg_prev_queue_enqueue. 3) In case enqueueing was successful, the skb is also queued up in the device queue, round-robin picks a next online CPU, and schedules the decryption worker. 4) The wg_packet_decrypt_worker, once scheduled, picks these up from the queue, decrypts the packets and once done calls into wg_queue_enqueue_per_peer_rx. 5) The latter updates the state to PACKET_STATE_CRYPTED on success and calls napi_schedule on the per peer->napi instance. 6) NAPI then polls via wg_packet_rx_poll. wg_prev_queue_peek checks on the peer->rx_queue. It will wg_prev_queue_dequeue if the queue->peeked skb was not cached yet, or just return the latter otherwise. (wg_prev_queue_drop_peeked later clears the cache.) 7) From an ordering perspective, the peer->rx_queue has skbs in order while the device queue with the per-CPU worker threads from a global ordering PoV can finish the decryption and signal the skb PACKET_STATE_CRYPTED out of order. 8) A situation can be observed that the first packet coming in will be stuck waiting for the decryption worker to be scheduled for a longer time when the system is under pressure. 9) While this is the case, the other CPUs in the meantime finish decryption and call into napi_schedule. 10) Now in wg_packet_rx_poll it picks up the first in-order skb from the peer->rx_queue and sees that its state is still PACKET_STATE_UNCRYPTED. The NAPI poll routine then exits e ---truncated---

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 6 · Red Hat Enterprise Linux 7

In the Linux kernel, the following vulnerability has been resolved: net: skbuff: fix missing zerocopy reference in pskb_carve helpers pskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy the old skb_shared_info header into a new buffer via memcpy(), which includes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs. Neither function calls net_zcopy_get() for the new shinfo, creating an unaccounted holder: every skb_shared_info with destructor_arg set will call skb_zcopy_clear() once when freed, but the corresponding net_zcopy_get() was never called for the new copy. Repeated calls drive uarg->refcnt to zero prematurely, freeing ubuf_info_msgzc while TX skbs still hold live destructor_arg pointers. KASAN reports use-after-free on a freed ubuf_info_msgzc: BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810 Read of size 8 at addr ffff88801574d3e8 by task poc/220 Call Trace: skb_release_data+0x77b/0x810 kfree_skb_list_reason+0x13e/0x610 skb_release_data+0x4cd/0x810 sk_skb_reason_drop+0xf3/0x340 skb_queue_purge_reason+0x282/0x440 rds_tcp_inc_free+0x1e/0x30 rds_recvmsg+0x354/0x1780 __sys_recvmsg+0xdf/0x180 Allocated by task 219: msg_zerocopy_realloc+0x157/0x7b0 tcp_sendmsg_locked+0x2892/0x3ba0 Freed by task 219: ip_recv_error+0x74a/0xb10 tcp_recvmsg+0x475/0x530 The skb consuming the late access still referenced the same uarg via shinfo->destructor_arg copied by pskb_carve_inside_nonlinear() without a refcount bump. This has been verified to be reliably exploitable: a working proof-of-concept achieves full root privilege escalation from an unprivileged local user on a default kernel configuration. The fix follows the pattern of pskb_expand_head() which has the same memcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get() is placed after skb_orphan_frags() succeeds, so the orphan error path needs no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is placed after all failure points and just before skb_release_data(), so no error path needs cleanup at all -- matching pskb_expand_head() more closely and avoiding the need for a balancing net_zcopy_put().

Linux · Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_log: validate MAC header was set before dumping it The fallback path of dump_mac_header() guards the MAC header access only with "skb->mac_header != skb->network_header", without checking skb_mac_header_was_set(). When the MAC header is unset, mac_header is 0xffff, so the test passes and skb_mac_header(skb) returns skb->head + 0xffff, ~64 KiB past the buffer; the loop then reads dev->hard_header_len bytes out of bounds into the kernel log. This is reachable via the netdev logger: nf_log_unknown_packet() calls dump_mac_header() unconditionally, and an skb sent through AF_PACKET with PACKET_QDISC_BYPASS reaches the egress hook with mac_header still unset (__dev_queue_xmit(), which would reset it, is bypassed). Add the skb_mac_header_was_set() check the ARPHRD_ETHER path already uses, and replace the open-coded MAC header length test with skb_mac_header_len(). Only skbs with an unset MAC header are affected; valid ones are dumped as before. BUG: KASAN: slab-out-of-bounds in dump_mac_header (net/netfilter/nf_log_syslog.c:831) Read of size 1 at addr ffff88800ea49d3f by task exploit/148 Call Trace: kasan_report (mm/kasan/report.c:595) dump_mac_header (net/netfilter/nf_log_syslog.c:831) nf_log_netdev_packet (net/netfilter/nf_log_syslog.c:938 net/netfilter/nf_log_syslog.c:963) nf_log_packet (net/netfilter/nf_log.c:260) nft_log_eval (net/netfilter/nft_log.c:60) nft_do_chain (net/netfilter/nf_tables_core.c:285) nft_do_chain_netdev (net/netfilter/nft_chain_filter.c:307) nf_hook_slow (net/netfilter/core.c:619) nf_hook_direct_egress (net/packet/af_packet.c:257) packet_xmit (net/packet/af_packet.c:280) packet_sendmsg (net/packet/af_packet.c:3114) __sys_sendto (net/socket.c:2265)

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: xfrm: espintcp: do not reuse an in-progress partial send espintcp keeps a single in-flight transmit in ctx->partial. Before building a new sk_msg, espintcp_sendmsg() first tries to flush that state through espintcp_push_msgs(). For blocking callers, espintcp_push_msgs() may return success even when the previous partial send is still pending. espintcp_sendmsg() would then reinitialize emsg->skmsg and reuse ctx->partial while the old transfer still owns that state. Do not rebuild the send message when ctx->partial is still in progress. If espintcp_push_msgs() returns with emsg->len still set, fail the new send instead of overwriting the live partial state. This is a memory-safety fix: reusing the live partial-send state can leave a stale offset attached to a new sk_msg and lead to an out-of- bounds read in the send path. tcp_sendmsg_locked() already handles waiting for send buffer memory, so the fix here is just to preserve espintcp's one-message-at-a-time transmit state.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: batman-adv: tvlv: reject oversized TVLV packets batadv_tvlv_container_ogm_append() builds a TVLV packet section from the tvlv.container_list. The total size of this section is computed by batadv_tvlv_container_list_size(), which sums the sizes of all registered containers. The return type and accumulator in batadv_tvlv_container_list_size() were u16. If the accumulated size exceeds U16_MAX, the value wraps around, causing the subsequent allocation in batadv_tvlv_container_ogm_append() to be undersized. The memcpy-style copy that follows would then write beyond the end of the allocated buffer, corrupting kernel memory. Fix this by widening the return type of batadv_tvlv_container_list_size() to size_t. In batadv_tvlv_container_ogm_append(), check the computed length against U16_MAX before proceeding, and bail out as if the allocation had failed when the limit is exceeded.

Linux · Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

In the Linux kernel, the following vulnerability has been resolved: io_uring/poll: fix signed comparison in io_poll_get_ownership() io_poll_get_ownership() uses a signed comparison to check whether poll_refs has reached the threshold for the slowpath: if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS)) atomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG (BIT(31)) is set in poll_refs, the value becomes negative in signed arithmetic, so the >= 128 comparison always evaluates to false and the slowpath is never taken. Fix this by casting the atomic_read() result to unsigned int before the comparison, so that the cancel flag is treated as a large positive value and correctly triggers the slowpath.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: xfrm: ipcomp: Free destination pages on acomp errors Move the out_free_req label up by a couple of lines so that the allocated dst SG list gets freed on error as well as success.

Linux · Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: sctp: stream: fully roll back denied add-stream state When ADD_OUT_STREAMS is denied, SCTP only shrinks the queued chunks and then lowers outcnt. That leaves removed stream metadata behind, so a later re-add can reuse a stale ext and hit a null-pointer dereference in the scheduler get path. Fix the rollback by tearing down the removed stream state the same way other stream resizes do. Unschedule the current scheduler state, drop the removed stream ext state with sctp_stream_outq_migrate(), and then reschedule the remaining streams. This keeps scheduler-private RR/FC/PRIO lists consistent while fully rolling back denied outgoing stream additions.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: netfilter: ebtables: fix OOB read in compat_mtw_from_user Luxiao Xu says: The function compat_mtw_from_user() converts ebtables extensions from 32-bit user structures to kernel native structures. However, it lacks proper validation of the user-supplied match_size/target_size. When certain extensions are processed, the kernel-side translation logic may perform memory accesses based on the extension's expected size. If the user provides a size smaller than what the extension requires, it results in an out-of-bounds read as reported by KASAN. This fix introduces a check to ensure match_size is at least as large as the extension's required compatsize. This covers matches, watchers, and targets, while maintaining compatibility with standard targets. AFAIU this is relevant for matches that need to go though match->compat_from_user() call. Those that use plain memcpy with the user-provided size are ok because the caller checks that size vs the start of the next rule entry offset (which itself is checked vs. total size copied from userspace). The ->compat_from_user() callbacks assume they can read compatsize bytes, so they need this extra check. Based on an earlier patch from Luxiao Xu.

Linux · Red Hat Enterprise Linux 10 · Red Hat Enterprise Linux 10.0 Extended Update Support · Red Hat Enterprise Linux 7 Extended Lifecycle Support

In the Linux kernel, the following vulnerability has been resolved: ipc: limit next_id allocation to the valid ID range The checkpoint/restore sysctl path can request the next SysV IPC id through ids->next_id. ipc_idr_alloc() currently forwards that request to idr_alloc() with an open-ended upper bound. If the valid tail of the SysV IPC id space is full, the allocation can spill beyond ipc_mni. The returned SysV IPC id still uses the normal index encoding, so later lookup and removal can target the wrong slot. This leaves the real IDR entry behind and breaks the IDR state for the object. The bug is in ipc_idr_alloc() in the checkpoint/restore path. 1. ids->next_id is passed to: idr_alloc(&ids->ipcs_idr, new, ipcid_to_idx(next_id), 0, ...) 2. The zero upper bound makes the allocation effectively open-ended. Once the valid SysV IPC tail is occupied, idr_alloc() can spill past ipc_mni and allocate an entry beyond the valid IPC id range. 3. The new object id is still encoded with the narrower SysV IPC index width: new->id = (new->seq << ipcmni_seq_shift()) + idx 4. Later removal goes through ipc_rmid(), which uses: ipcid_to_idx(ipcp->id) That truncates the real IDR index. An object actually stored at a high index can then be removed as if it lived at a low in-range index. 5. For shared memory, shm_destroy() frees the current object anyway, but the real high IDR slot is left behind as a dangling pointer. 6. A subsequent walk of /proc/sysvipc/shm reaches the stale IDR entry and dereferences freed memory. Prevent this by bounding the requested allocation to ipc_mni so the checkpoint/restore path fails once the valid range is exhausted.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: batman-adv: dat: handle forward allocation error batadv_dat_forward_data() calls pskb_copy_for_clone() to duplicate an skb for each DHT candidate, but does not check the return value before passing it to batadv_send_skb_prepare_unicast_4addr(). That function dereferences the skb unconditionally, so a failed allocation triggers a NULL pointer dereference. Skip forwarding to the current DHT candidate on allocation failure.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_policy: fix strict mode inbound policy matching match_policy_in() walks sec_path entries from the last transform to the first one, but strict policy matching needs to consume info->pol[] in the same forward order as the rule layout. Derive the strict-match policy position from the number of transforms already consumed so that multi-element inbound rules are matched consistently.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix tp_meter counter underflow during shutdown batadv_tp_sender_shutdown() unconditionally decrements the "sending" atomic counter. If multiple paths (e.g. timeout, user cancel, and normal finish) call this function, the counter can underflow to -1. Since the sender logic treats any non-zero value as "still sending", a negative value causes the sender kthread to loop indefinitely. This leads to a use-after-free when the interface is removed while the zombie thread is still active. Fix this by using atomic_xchg() to ensure the counter only transitions from 1 to 0 once. [sven: added missing change in batadv_tp_send]

Linux · Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: serialize accept_q access bt_sock_poll() walks the accept queue without synchronization, while child teardown can unlink the same socket and drop its last reference. The unsynchronized accept queue walk has existed since the initial Bluetooth import. Protect accept_q with a dedicated lock for queue updates and polling. Also rework bt_accept_dequeue() to take temporary child references under the queue lock before dropping it and locking the child socket.

Linux · Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: sctp: diag: reject stale associations in dump_one path The SCTP exact sock_diag lookup can hold a transport reference, block on lock_sock(sk), and then resume after sctp_association_free() has marked the association dead and freed its bind address list. When that happens, inet_assoc_attr_size() and inet_diag_msg_sctpasoc_fill() can still dereference association state that is no longer valid for reporting. In particular, inet_diag_msg_sctpasoc_fill() may read an empty bind-address list as a real sctp_sockaddr_entry and trigger an out-of-bounds read from unrelated association memory. Reject the association after taking the socket lock if it has been reaped or detached from the endpoint, and report the lookup as stale. This keeps the exact dump-one path from formatting torn association state.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: netfilter: ip6t_hbh: reject oversized option lists struct ip6t_opts stores at most IP6T_OPTS_OPTSNR option descriptors, but hbh_mt6_check() does not reject larger optsnr values supplied from userspace. Validate optsnr in the rule setup path so only match data that fits the fixed-size opts array can be installed. This follows the existing xtables pattern of rejecting invalid user-provided counts in checkentry() and keeps the packet matching path unchanged. `struct ip6t_opts` has a fixed `opts[IP6T_OPTS_OPTSNR]` array, where `IP6T_OPTS_OPTSNR` is 16, then off-by-one array access is possible: [ 137.924693][ T8692] UBSAN: array-index-out-of-bounds in ../net/ipv6/netfilter/ip6t_hbh.c:110:29 [ 137.926167][ T8692] index 16 is out of range for type '__u16 [16]'

Linux · Siemens SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens SIPLUS S7-1500 CPU 1518-4 PN/DP MFP

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_queue: hold bridge skb->dev while queued br_pass_frame_up() rewrites skb->dev from the ingress port to the bridge master before queueing bridge LOCAL_IN packets. NFQUEUE only holds references on state.in/out and bridge physdevs, so a queued bridge packet can retain a freed bridge master in skb->dev until reinjection. When the verdict is reinjected later, br_netif_receive_skb() re-enters the receive path with skb->dev still pointing at the freed bridge master, triggering a use-after-free. Store skb->dev in the queue entry, hold a reference on it for the queue lifetime, and use the saved device when dropping queued packets during NETDEV_DOWN handling.