Jeudi 28 mai 2026

Linux · Red Hat Enterprise Linux 8 · Red Hat Enterprise Linux 9 · Red Hat Enterprise Linux 10

In the Linux kernel, the following vulnerability has been resolved: smb: client: validate dacloffset before building DACL pointers parse_sec_desc(), build_sec_desc(), and the chown path in id_mode_to_cifs_acl() all add the server-supplied dacloffset to pntsd before proving a DACL header fits inside the returned security descriptor. On 32-bit builds a malicious server can return dacloffset near U32_MAX, wrap the derived DACL pointer below end_of_acl, and then slip past the later pointer-based bounds checks. build_sec_desc() and id_mode_to_cifs_acl() can then dereference DACL fields from the wrapped pointer in the chmod/chown rewrite paths. Validate dacloffset numerically before building any DACL pointer and reuse the same helper at the three DACL entry points.

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

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix out-of-bounds read in symlink_data() Since smb2_check_message() returns success without length validation for the symlink error response, in symlink_data() it is possible for iov->iov_len to be smaller than sizeof(struct smb2_err_rsp). If the buffer only contains the base SMB2 header (64 bytes), accessing err->ErrorContextCount (at offset 66) or err->ByteCount later in symlink_data() will cause an out-of-bounds read.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: smb/client: fix out-of-bounds read in smb2_compound_op() If a server sends a truncated response but a large OutputBufferLength, and terminates the EA list early, check_wsl_eas() returns success without validating that the entire OutputBufferLength fits within iov_len. Then smb2_compound_op() does: memcpy(idata->wsl.eas, data[0], size[0]); Where size[0] is OutputBufferLength. If iov_len is smaller than size[0], memcpy can read beyond the end of the rsp_iov allocation and leak adjacent kernel heap memory.

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

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: ADD_ADDR rtx: fix potential data-race This mptcp_pm_add_timer() helper is executed as a timer callback in softirq context. To avoid any data races, the socket lock needs to be held with bh_lock_sock(). If the socket is in use, retry again soon after, similar to what is done with the keepalive timer.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: nvmet-tcp: fix race between ICReq handling and queue teardown nvmet_tcp_handle_icreq() updates queue->state after sending an Initialization Connection Response (ICResp), but it does so without serializing against target-side queue teardown. If an NVMe/TCP host sends an Initialization Connection Request (ICReq) and immediately closes the connection, target-side teardown may start in softirq context before io_work drains the already buffered ICReq. In that case, nvmet_tcp_schedule_release_queue() sets queue->state to NVMET_TCP_Q_DISCONNECTING and drops the queue reference under state_lock. If io_work later processes that ICReq, nvmet_tcp_handle_icreq() can still overwrite the state back to NVMET_TCP_Q_LIVE. That defeats the DISCONNECTING-state guard in nvmet_tcp_schedule_release_queue() and allows a later socket state change to re-enter teardown and issue a second kref_put() on an already released queue. The ICResp send failure path has the same problem. If teardown has already moved the queue to DISCONNECTING, a send error can still overwrite the state with NVMET_TCP_Q_FAILED, again reopening the window for a second teardown path to drop the queue reference. Fix this by serializing both post-send state transitions with state_lock and bailing out if teardown has already started. Use -ESHUTDOWN as an internal sentinel for that bail-out path rather than propagating it as a transport error like -ECONNRESET. Keep nvmet_tcp_socket_error() setting rcv_state to NVMET_TCP_RECV_ERR before honoring that sentinel so receive-side parsing stays quiesced until the existing release path completes.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: libceph: Fix slab-out-of-bounds access in auth message processing If a (potentially corrupted) message of type CEPH_MSG_AUTH_REPLY contains a positive value in its result field, it is treated as an error code by ceph_handle_auth_reply() and returned to handle_auth_reply(). Thereafter, an attempt is made to send the preallocated message of type CEPH_MSG_AUTH, where the returned value is interpreted as the size of the front segment to send. If the result value in the message is greater than the size of the memory buffer allocated for the front segment, an out-of-bounds access occurs, and the content of the memory region beyond this buffer is sent out. This patch fixes the issue by treating only negative values in the result field as errors. Positive values are therefore treated as success in the same way as a zero value. Additionally, a BUG_ON is added to __send_prepared_auth_request() comparing the len parameter to front_alloc_len to prevent sending the message if it exceeds the bounds of the allocation and to make it easier to catch any logic flaws leading to this.

Linux · Linux linux kernel

In the Linux kernel, the following vulnerability has been resolved: block: add pgmap check to biovec_phys_mergeable biovec_phys_mergeable() is used by the request merge, DMA mapping, and integrity merge paths to decide if two physically contiguous bvec segments can be coalesced into one. It currently has no check for whether the segments belong to different dev_pagemaps. When zone device memory is registered in multiple chunks, each chunk gets its own dev_pagemap. A single bio can legitimately contain bvecs from different pgmaps -- iov_iter_extract_bvecs() breaks at pgmap boundaries but the outer loop in bio_iov_iter_get_pages() continues filling the same bio. If such bvecs are physically contiguous, biovec_phys_mergeable() will coalesce them, making it impossible to recover the correct pgmap for the merged segment via page_pgmap(). Add a zone_device_pages_have_same_pgmap() check to prevent merging bvec segments that span different pgmaps.