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In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix NULL sink dereference in USB4 bandwidth functions allocate_usb4_bandwidth_for_stream() and allocate_usb4_bandwidth() both use ASSERT(stream->sink) before dereferencing stream->sink->link. ASSERT is compiled out in production builds, so a NULL stream->sink causes a NULL pointer dereference. link_set_dpms_off() already guards two earlier accesses to stream->sink with explicit NULL checks, confirming that stream->sink can legit…

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: don't drop the runtime PM reference twice in amdgpu_gpr amdgpu_debugfs_gpr_read() drops its runtime PM reference right after reading the wave registers. When copying them to userspace fails, it jumps to the err label, which drops the reference a second time. A read into a bad buffer on Navi31 either steals a reference somebody else holds (power/runtime_usage goes from 1 to 0) or underflows the count: amdgpu 0000:03:00.0: Runtime PM…

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix GEM object leak on ENOMEM in userptr ioctl When amdgpu_hmm_range_alloc() fails amdgpu_gem_userptr_ioctl() returns -ENOMEM right away and skips the cleanup every other error path goes through. The GEM object, the bo->parent reference on the VM root and the MMU notifier registration are all left behind. Use release_object here, not user_pages_done, range is still NULL at this point. (cherry picked from commit bbe739e407a542073ec1a…

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: keep the eviction fence until the last handle is closed amdgpu_gem_object_close() detaches the user queue eviction fence from the BO before it checks bo_va->ref_count, so closing any handle of a BO removes the fence, even when the file still has another handle to the BO and the bo_va with its GPU mappings stays. The BO can then be evicted without suspending the user queues of the file, which keep accessing it through mappings that are…

In the Linux kernel, the following vulnerability has been resolved: drm/exec: don't immediately add prelocked obj to array of locked objs When a contention is detected the drm_exec object grabs a reference to the contended object, unlocks all other objects and pre-locks the contended one before anything else. The problem is that it is possible that this pre-locked object was about to be destroyed and drm_exec is now holding the last reference to it. So we never actually see this pre-locked object again to be ex…

In the Linux kernel, the following vulnerability has been resolved: drm/i915/dmc: Add sanity check for DMC load address For DMC firmware header version 3, the firmware load address is stored in dmc_info->start_mmioaddr and later used by dmc_load_program(). Unlike the MMIO address table, the firmware load address is not validated. Add a sanity check to ensure it is within the valid range. BSpec: 69671, 68378 (cherry picked from commit 5e47ee5c76ca9becde8df4ad5202845b7ffcbc4c)

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Don't transfer shrinker pages for pinned bos on purgeable state change Pinned bos have their pages removed from the shrinker's shrinkable / purgeable counts on pin, and added back on unpin according to the bo's purgeable state at that time. However, xe_bo_set_purgeable_shrinker() unconditionally transfers pages between the shrinkable and purgeable counts. If the purgeable state of a pinned bo changes, for example by userspace madvising D…

In the Linux kernel, the following vulnerability has been resolved: sched_ext: Fix use-after-free of a destroyed user DSQ by a deferred reenqueue A deferred reenqueue can read a freed user DSQ. The request stays on its CPU's deferred list until run_deferred() takes it, and the RCU callback that frees the DSQ assumes that the grace period has flushed it, so exit_dsq() checks the per-CPU node without the deferred list lock. A grace period waits for readers in flight, not for a pending run_deferred(). A run_deferred…

In the Linux kernel, the following vulnerability has been resolved: tracing: Keep the predicate limit separate from program capacity predicate_parse() adds two to nr_preds to reserve the terminal TRUE and FALSE entries. It also uses that increased value as the limit for parsed predicates. If the initial count is smaller than the number actually parsed, the program can fill the allocation and subsequent accesses can go past its end. Keep nr_preds as the predicate limit and use a separate value for the allocation …

In the Linux kernel, the following vulnerability has been resolved: tracing: Check operator stack capacity before pushing predicate_parse() uses the first operator stack entry before processing any opening parentheses. A push then increments top before writing. The existing check still permits that write when top already points to the last allocated entry, which can access beyond the operator stack. Reject the push when top reaches the last allocated entry.

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix crash in print_graph_function_event() tracing_set_tracer() assigns the flags of the newly selected tracer with: tr->current_trace_flags = t->flags ? : t->tracer->flags; If the new tracer defines neither static flags nor default flags, like hwlat, irqsoff or wakeup, add_tracer() has no per instance flags copy for it, and both operands are NULL, so tr->current_trace_flags ends up being NULL as well. The ring buffer is not cleared w…

In the Linux kernel, the following vulnerability has been resolved: tracing: Fix hist trigger timestamps for buffered events Syzkaller triggered a WARN_ON_ONCE(!nest) warning: WARNING: kernel/trace/ring_buffer.c:821 at ring_buffer_event_time_stamp Call trace: ring_buffer_event_time_stamp hist_field_timestamp hist_fn_call event_hist_trigger event_triggers_call __event_trigger_test_discard trace_event_buffer_commit do_trace_event_raw_event_sched_switch trace_event_raw_event_…

In the Linux kernel, the following vulnerability has been resolved: tcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION) do_tcp_getsockopt() reads icsk->icsk_ca_ops->name without holding rcu_read_lock(). Since commit 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf"), icsk_ca_ops can point to dynamically allocated BPF struct_ops memory that may be freed concurrently via setsockopt(TCP_CONGESTION), leading to a use-after-free. BUG: KASAN: slab-use-after-free in _copy_to_user+0x37/0x60 Read o…

In the Linux kernel, the following vulnerability has been resolved: tcp: fix use-after-free in do_tcp_getsockopt(TCP_CC_INFO) do_tcp_getsockopt() reads icsk->icsk_ca_ops and dereferences the get_info function pointer without rcu_read_lock(). With BPF struct_ops congestion control, ca_ops can point to dynamically allocated memory that is freed concurrently, resulting in a use-after-free when the kernel dereferences or calls through the stale pointer. BUG: KASAN: slab-use-after-free in do_tcp_getsockopt+0x2037/0…

In the Linux kernel, the following vulnerability has been resolved: cifs: don't update i_size in cifs_do_truncate without a cached handle If find_writable_file() returns null, cifs_file_flush will return 0 without issuing set_file_size, and the outer 'if (!rc)' block will set i_size to 0 before telling the server to truncate. If the cifs_open() then fails, the inode will have size 0, while the server file is unchanged. Move the netfs_resize_file() and cifs_setsize() into the 'if (cfile)', so they only run after…

In the Linux kernel, the following vulnerability has been resolved: dm-crypt: fix a tiny race condition in crypt_dec_pending crypt_dec_pending reads io->error before calling atomic_dec_and_test. Another context, for example crypt_endio called from an interrupt, may set io->error and drop its reference between the read and the decrement. crypt_dec_pending then drops the last reference and completes the bio with the stale status - so a read that failed and was never decrypted, or a write that failed, is reported as…

In the Linux kernel, the following vulnerability has been resolved: dm-integrity: fix infinite loop on discard with large tag size When integrity_metadata handles a discard, it fills a buffer with DISCARD_FILLER and writes it over the tags, max_blocks blocks at a time. If the kmalloc fails, the buffer is the on-stack array checksums_onstack and max_size is set to HASH_MAX_DIGESTSIZE. So if the tag size is larger than HASH_MAX_DIGESTSIZE, max_blocks is zero, bi_size is never decremented and the loop never terminat…

In the Linux kernel, the following vulnerability has been resolved: mac802154: fix data race and NULL deref on local->assoc_dev local->assoc_dev is shared between the association path and the association-response worker without common synchronization. mac802154_perform_association() stores the coordinator pointer and waits for a response. Its timeout and error paths clear the pointer and return to mac802154_associate(), which may then free the coordinator object. Meanwhile, mac802154_rx_mac_cmd_worker() may obse…

In the Linux kernel, the following vulnerability has been resolved: net/iucv: fix the recvmsg window update iucv_sock_recvmsg() sends the HiperSockets-only AF_IUCV_FLAG_WIN without testing the transport, so on a classic z/VM socket iucv_send_ctrl() sizes the skb through a NULL iucv->hs_dev. SO_MSGLIMIT accepts 1, so msglimit / 2 is zero and one recvmsg() on its own socket is enough for an unprivileged process to take a spurious disconnect. It also calls iucv_send_ctrl() under spin_lock_bh(&message_q.lock), which…

In the Linux kernel, the following vulnerability has been resolved: xfs: don't hold buffer locks across sync transaction commit in xfs_sync_sb_buf xfs_sync_sb_buf() holds sb/rtsb buffer locks across a synchronous xfs_trans_commit(), which flushes the CIL push workqueue internally. If shutdown occurs during the CIL push, xfs_buf_item_unpin() needs to lock these buffers to fail them, causing a deadlock: setlabel: holds buf lock -> flush_workqueue(xfs-cil) CIL push worker: xfs_buf_item_unpin -> xfs_b…

In the Linux kernel, the following vulnerability has been resolved: xfs: fix capability check in xfs An user reported a bug where he managed to evade group's quota by changing a file's gid to a different group id the same user belonged to, even though quotas were enforced on both gids and the file's size was big enough to exceed the quota's hardlimit. Commit eba0549bc7d1 replaced a capable() call by a has_capability_noaudit() to prevent unnecessary selinux audit messages. Turns out that both calls have slightly …

In the Linux kernel, the following vulnerability has been resolved: io_uring/cancel: don't spin on local work the task can't run io_uring_cancel_generic() refuses to sleep while any ring on the exiting task's tctx has local work pending. It assumes the task is that ring's submitter and that the next io_uring_try_cancel_requests() pass will run the work. This does not hold for a ring that was still IORING_SETUP_R_DISABLED when the task got its tctx node from io_uring_create() or io_ringfd_register(). The submitter…

In the Linux kernel, the following vulnerability has been resolved: selinux: fix BPF token permission checks Avoid multiple lookups of the bpffs creator SID using the token's file descriptor when the same information can be found via the resolved path/dentry (in selinux_bpf_token_create()) or the token itself (in selinux_bpf_map_create() and selinux_bpf_prog_load()). Not only does this simplify the code, it avoids potential TOCTOU issues if the user changes the token file descriptor passed into the kernel.

In the Linux kernel, the following vulnerability has been resolved: sctp: validate chunk length in the inqueue parser SCTP chunks always include a four-byte generic header, but sctp_inq_pop() currently accepts shorter declared lengths. A zero-length chunk leaves chunk_end at the current header. When ASCONF is covered by the association's SCTP-AUTH policy, sctp_assoc_bh_rcv() can continue before the state machine performs its normal chunk-length check. sctp_inq_pop() then returns the same malformed chunk repeated…

In the Linux kernel, the following vulnerability has been resolved: page_pool: keep frag_offset aligned for odd-sized requests page_pool_alloc_frag_netmem() rounds the requested fragment size with size = ALIGN(size, dma_get_cache_alignment()); dma_get_cache_alignment() returns 1 unless the architecture defines ARCH_DMA_MINALIGN, which DMA-coherent architectures such as x86 do not. There the ALIGN() is a no-op and pool->frag_offset advances by the raw, unrounded size. A single caller asking for an odd size the…