In the Linux kernel, the following vulnerability has been resolved: drm/i915/gt: Fix timeline left held on VMA alloc error The following error has been reported sporadically by CI when a test unbinds the i915 driver on a ring submission platform: <4> [239.330153] ------------[ cut here ]------------ <4> [239.330166] i915 0000:00:02.0: [drm] drm_WARN_ON(dev_priv->mm.shrink_count) <4> [239.330196] WARNING: CPU: 1 PID: 18570 at drivers/gpu/drm/i915/i915_gem.c:1309 i915_gem_cleanup_early+0x13e/0x150 [i915] ... <4> [239.330640] RIP: 0010:i915_gem_cleanup_early+0x13e/0x150 [i915] ... <4> [239.330942] Call Trace: <4> [239.330944] <TASK> <4> [239.330949] i915_driver_late_release+0x2b/0xa0 [i915] <4> [239.331202] i915_driver_release+0x86/0xa0 [i915] <4> [239.331482] devm_drm_dev_init_release+0x61/0x90 <4> [239.331494] devm_action_release+0x15/0x30 <4> [239.331504] release_nodes+0x3d/0x120 <4> [239.331517] devres_release_all+0x96/0xd0 <4> [239.331533] device_unbind_cleanup+0x12/0x80 <4> [239.331543] device_release_driver_internal+0x23a/0x280 <4> [239.331550] ? bus_find_device+0xa5/0xe0 <4> [239.331563] device_driver_detach+0x14/0x20 ... <4> [357.719679] ---[ end trace 0000000000000000 ]--- If the test also unloads the i915 module then that's followed with: <3> [357.787478] ============================================================================= <3> [357.788006] BUG i915_vma (Tainted: G U W N ): Objects remaining on __kmem_cache_shutdown() <3> [357.788031] ----------------------------------------------------------------------------- <3> [357.788204] Object 0xffff888109e7f480 @offset=29824 <3> [357.788670] Allocated in i915_vma_instance+0xee/0xc10 [i915] age=292729 cpu=4 pid=2244 <4> [357.788994] i915_vma_instance+0xee/0xc10 [i915] <4> [357.789290] init_status_page+0x7b/0x420 [i915] <4> [357.789532] intel_engines_init+0x1d8/0x980 [i915] <4> [357.789772] intel_gt_init+0x175/0x450 [i915] <4> [357.790014] i915_gem_init+0x113/0x340 [i915] <4> [357.790281] i915_driver_probe+0x847/0xed0 [i915] <4> [357.790504] i915_pci_probe+0xe6/0x220 [i915] ... Closer analysis of CI results history has revealed a dependency of the error on a few IGT tests, namely: - igt@api_intel_allocator@fork-simple-stress-signal, - igt@api_intel_allocator@two-level-inception-interruptible, - igt@gem_linear_blits@interruptible, - igt@prime_mmap_coherency@ioctl-errors, which invisibly trigger the issue, then exhibited with first driver unbind attempt. All of the above tests perform actions which are actively interrupted with signals. Further debugging has allowed to narrow that scope down to DRM_IOCTL_I915_GEM_EXECBUFFER2, and ring_context_alloc(), specific to ring submission, in particular. If successful then that function, or its execlists or GuC submission equivalent, is supposed to be called only once per GEM context engine, followed by raise of a flag that prevents the function from being called again. The function is expected to unwind its internal errors itself, so it may be safely called once more after it returns an error. In case of ring submission, the function first gets a reference to the engine's legacy timeline and then allocates a VMA. If the VMA allocation fails, e.g. when i915_vma_instance() called from inside is interrupted with a signal, then ring_context_alloc() fails, leaving the timeline held referenced. On next I915_GEM_EXECBUFFER2 IOCTL, another reference to the timeline is got, and only that last one is put on successful completion. As a consequence, the legacy timeline, with its underlying engine status page's VMA object, is still held and not released on driver unbind. Get the legacy timeline only after successful allocation of the context engine's VMA. v2: Add a note on other submission methods (Krzysztof Karas): Both execlists and GuC submission use lrc_alloc() which seems free from a similar issue. (cherry picked from commit cc43422b3cc79eacff4c5a8ba0d224688ca9dd4f)

In the Linux kernel, the following vulnerability has been resolved: platform/x86: dell-wmi-sysman: Avoid buffer overflow in current_password_store() If the 'buf' array received from the user contains an empty string, the 'length' variable will be zero. Accessing the 'buf' array element with index 'length - 1' will result in a buffer overflow. Add a check for an empty string. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: xfrm: interface: fix use-after-free after changing collect_md xfrm interface collect_md property on xfrm interfaces can only be set on device creation, thus xfrmi_changelink() should fail when called on such interfaces. The check to enforce this was done only in the case where the xi was returned from xfrmi_locate() which doesn't look for the collect_md interface, and thus the validation was never reached. Calling changelink would thus errornously place the special interface xi in the xfrmi_net->xfrmi hash, but since it also exists in the xfrmi_net->collect_md_xfrmi pointer it would lead to a double free when the net namespace was taken down [1]. Change the check to use the xi from netdev_priv which is available earlier in the function to prevent changes in xfrm collect_md interfaces. [1] resulting oops: [ 8.516540] kernel BUG at net/core/dev.c:12029! [ 8.516552] Oops: invalid opcode: 0000 [#1] SMP NOPTI [ 8.516559] CPU: 0 UID: 0 PID: 12 Comm: kworker/u80:0 Not tainted 6.15.0-virtme #5 PREEMPT(voluntary) [ 8.516565] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 [ 8.516569] Workqueue: netns cleanup_net [ 8.516579] RIP: 0010:unregister_netdevice_many_notify+0x101/0xab0 [ 8.516590] Code: 90 0f 0b 90 48 8b b0 78 01 00 00 48 8b 90 80 01 00 00 48 89 56 08 48 89 32 4c 89 80 78 01 00 00 48 89 b8 80 01 00 00 eb ac 90 <0f> 0b 48 8b 45 00 4c 8d a0 88 fe ff ff 48 39 c5 74 5c 41 80 bc 24 [ 8.516593] RSP: 0018:ffffa93b8006bd30 EFLAGS: 00010206 [ 8.516598] RAX: ffff98fe4226e000 RBX: ffffa93b8006bd58 RCX: ffffa93b8006bc60 [ 8.516601] RDX: 0000000000000004 RSI: 0000000000000000 RDI: dead000000000122 [ 8.516603] RBP: ffffa93b8006bdd8 R08: dead000000000100 R09: ffff98fe4133c100 [ 8.516605] R10: 0000000000000000 R11: 00000000000003d2 R12: ffffa93b8006be00 [ 8.516608] R13: ffffffff96c1a510 R14: ffffffff96c1a510 R15: ffffa93b8006be00 [ 8.516615] FS: 0000000000000000(0000) GS:ffff98fee73b7000(0000) knlGS:0000000000000000 [ 8.516619] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8.516622] CR2: 00007fcd2abd0700 CR3: 000000003aa40000 CR4: 0000000000752ef0 [ 8.516625] PKRU: 55555554 [ 8.516627] Call Trace: [ 8.516632] <TASK> [ 8.516635] ? rtnl_is_locked+0x15/0x20 [ 8.516641] ? unregister_netdevice_queue+0x29/0xf0 [ 8.516650] ops_undo_list+0x1f2/0x220 [ 8.516659] cleanup_net+0x1ad/0x2e0 [ 8.516664] process_one_work+0x160/0x380 [ 8.516673] worker_thread+0x2aa/0x3c0 [ 8.516679] ? __pfx_worker_thread+0x10/0x10 [ 8.516686] kthread+0xfb/0x200 [ 8.516690] ? __pfx_kthread+0x10/0x10 [ 8.516693] ? __pfx_kthread+0x10/0x10 [ 8.516697] ret_from_fork+0x82/0xf0 [ 8.516705] ? __pfx_kthread+0x10/0x10 [ 8.516709] ret_from_fork_asm+0x1a/0x30 [ 8.516718] </TASK>

In the Linux kernel, the following vulnerability has been resolved: i2c: tegra: check msg length in SMBUS block read For SMBUS block read, do not continue to read if the message length passed from the device is '0' or greater than the maximum allowed bytes.

In the Linux kernel, the following vulnerability has been resolved: net: openvswitch: fix nested key length validation in the set() action It's not safe to access nla_len(ovs_key) if the data is smaller than the netlink header. Check that the attribute is OK first.

In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Fix potential buffer overflow in parse_ivrs_acpihid There is a string parsing logic error which can lead to an overflow of hid or uid buffers. Comparing ACPIID_LEN against a total string length doesn't take into account the lengths of individual hid and uid buffers so the check is insufficient in some cases. For example if the length of hid string is 4 and the length of the uid string is 260, the length of str will be equal to ACPIID_LEN + 1 but uid string will overflow uid buffer which size is 256. The same applies to the hid string with length 13 and uid string with length 250. Check the length of hid and uid strings separately to prevent buffer overflow. Found by Linux Verification Center (linuxtesting.org) with SVACE.

The mm subsystem in the Linux kernel through 3.2 does not properly enforce the CONFIG_STRICT_DEVMEM protection mechanism, which allows local users to read or write to kernel memory locations in the first megabyte (and bypass slab-allocation access restrictions) via an application that opens the /dev/mem file, related to arch/x86/mm/init.c and drivers/char/mem.c.

drivers/media/usb/dvb-usb-v2/dvb_usb_core.c in the Linux kernel 4.9.x and 4.10.x before 4.10.12 interacts incorrectly with the CONFIG_VMAP_STACK option, which allows local users to cause a denial of service (system crash or memory corruption) or possibly have unspecified other impact by leveraging use of more than one virtual page for a DMA scatterlist.

In the Linux kernel, the following vulnerability has been resolved: phy: tegra: xusb: Fix unbalanced regulator disable in UTMI PHY mode When transitioning from USB_ROLE_DEVICE to USB_ROLE_NONE, the code assumed that the regulator should be disabled. However, if the regulator is marked as always-on, regulator_is_enabled() continues to return true, leading to an incorrect attempt to disable a regulator which is not enabled. This can result in warnings such as: [ 250.155624] WARNING: CPU: 1 PID: 7326 at drivers/regulator/core.c:3004 _regulator_disable+0xe4/0x1a0 [ 250.155652] unbalanced disables for VIN_SYS_5V0 To fix this, we move the regulator control logic into tegra186_xusb_padctl_id_override() function since it's directly related to the ID override state. The regulator is now only disabled when the role transitions from USB_ROLE_HOST to USB_ROLE_NONE, by checking the VBUS_ID register. This ensures that regulator enable/disable operations are properly balanced and only occur when actually transitioning to/from host mode.

In the Linux kernel, the following vulnerability has been resolved: mcb: fix a double free bug in chameleon_parse_gdd() In chameleon_parse_gdd(), if mcb_device_register() fails, 'mdev' would be released in mcb_device_register() via put_device(). Thus, goto 'err' label and free 'mdev' again causes a double free. Just return if mcb_device_register() fails.

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: Reset IRTE to host control if *new* route isn't postable Restore an IRTE back to host control (remapped or posted MSI mode) if the *new* GSI route prevents posting the IRQ directly to a vCPU, regardless of the GSI routing type. Updating the IRTE if and only if the new GSI is an MSI results in KVM leaving an IRTE posting to a vCPU. The dangling IRTE can result in interrupts being incorrectly delivered to the guest, and in the worst case scenario can result in use-after-free, e.g. if the VM is torn down, but the underlying host IRQ isn't freed.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in kerberos authentication Setting sess->user = NULL was introduced to fix the dangling pointer created by ksmbd_free_user. However, it is possible another thread could be operating on the session and make use of sess->user after it has been passed to ksmbd_free_user but before sess->user is set to NULL.

In the Linux kernel, the following vulnerability has been resolved: Squashfs: check return result of sb_min_blocksize Syzkaller reports an "UBSAN: shift-out-of-bounds in squashfs_bio_read" bug. Syzkaller forks multiple processes which after mounting the Squashfs filesystem, issues an ioctl("/dev/loop0", LOOP_SET_BLOCK_SIZE, 0x8000). Now if this ioctl occurs at the same time another process is in the process of mounting a Squashfs filesystem on /dev/loop0, the failure occurs. When this happens the following code in squashfs_fill_super() fails. ---- msblk->devblksize = sb_min_blocksize(sb, SQUASHFS_DEVBLK_SIZE); msblk->devblksize_log2 = ffz(~msblk->devblksize); ---- sb_min_blocksize() returns 0, which means msblk->devblksize is set to 0. As a result, ffz(~msblk->devblksize) returns 64, and msblk->devblksize_log2 is set to 64. This subsequently causes the UBSAN: shift-out-of-bounds in fs/squashfs/block.c:195:36 shift exponent 64 is too large for 64-bit type 'u64' (aka 'unsigned long long') This commit adds a check for a 0 return by sb_min_blocksize().

In the Linux kernel, the following vulnerability has been resolved: jbd2: remove wrong sb->s_sequence check Journal emptiness is not determined by sb->s_sequence == 0 but rather by sb->s_start == 0 (which is set a few lines above). Furthermore 0 is a valid transaction ID so the check can spuriously trigger. Remove the invalid WARN_ON.

In the Linux kernel, the following vulnerability has been resolved: tls: always refresh the queue when reading sock After recent changes in net-next TCP compacts skbs much more aggressively. This unearthed a bug in TLS where we may try to operate on an old skb when checking if all skbs in the queue have matching decrypt state and geometry. BUG: KASAN: slab-use-after-free in tls_strp_check_rcv+0x898/0x9a0 [tls] (net/tls/tls_strp.c:436 net/tls/tls_strp.c:530 net/tls/tls_strp.c:544) Read of size 4 at addr ffff888013085750 by task tls/13529 CPU: 2 UID: 0 PID: 13529 Comm: tls Not tainted 6.16.0-rc5-virtme Call Trace: kasan_report+0xca/0x100 tls_strp_check_rcv+0x898/0x9a0 [tls] tls_rx_rec_wait+0x2c9/0x8d0 [tls] tls_sw_recvmsg+0x40f/0x1aa0 [tls] inet_recvmsg+0x1c3/0x1f0 Always reload the queue, fast path is to have the record in the queue when we wake, anyway (IOW the path going down "if !strp->stm.full_len").

NVIDIA GPU driver for Windows and Linux contains a vulnerability where a user can cause an out-of-bounds write. A successful exploit of this vulnerability might lead to code execution, denial of service, escalation of privileges, information disclosure, and data tampering.

In the Linux kernel, the following vulnerability has been resolved: bpf, sockmap: Avoid using sk_socket after free when sending The sk->sk_socket is not locked or referenced in backlog thread, and during the call to skb_send_sock(), there is a race condition with the release of sk_socket. All types of sockets(tcp/udp/unix/vsock) will be affected. Race conditions: ''' CPU0 CPU1 backlog::skb_send_sock sendmsg_unlocked sock_sendmsg sock_sendmsg_nosec close(fd): ... ops->release() -> sock_map_close() sk_socket->ops = NULL free(socket) sock->ops->sendmsg ^ panic here ''' The ref of psock become 0 after sock_map_close() executed. ''' void sock_map_close() { ... if (likely(psock)) { ... // !! here we remove psock and the ref of psock become 0 sock_map_remove_links(sk, psock) psock = sk_psock_get(sk); if (unlikely(!psock)) goto no_psock; <=== Control jumps here via goto ... cancel_delayed_work_sync(&psock->work); <=== not executed sk_psock_put(sk, psock); ... } ''' Based on the fact that we already wait for the workqueue to finish in sock_map_close() if psock is held, we simply increase the psock reference count to avoid race conditions. With this patch, if the backlog thread is running, sock_map_close() will wait for the backlog thread to complete and cancel all pending work. If no backlog running, any pending work that hasn't started by then will fail when invoked by sk_psock_get(), as the psock reference count have been zeroed, and sk_psock_drop() will cancel all jobs via cancel_delayed_work_sync(). In summary, we require synchronization to coordinate the backlog thread and close() thread. The panic I catched: ''' Workqueue: events sk_psock_backlog RIP: 0010:sock_sendmsg+0x21d/0x440 RAX: 0000000000000000 RBX: ffffc9000521fad8 RCX: 0000000000000001 ... Call Trace: <TASK> ? die_addr+0x40/0xa0 ? exc_general_protection+0x14c/0x230 ? asm_exc_general_protection+0x26/0x30 ? sock_sendmsg+0x21d/0x440 ? sock_sendmsg+0x3e0/0x440 ? __pfx_sock_sendmsg+0x10/0x10 __skb_send_sock+0x543/0xb70 sk_psock_backlog+0x247/0xb80 ... '''

In the Linux kernel, the following vulnerability has been resolved: atm: clip: Fix infinite recursive call of clip_push(). syzbot reported the splat below. [0] This happens if we call ioctl(ATMARP_MKIP) more than once. During the first call, clip_mkip() sets clip_push() to vcc->push(), and the second call copies it to clip_vcc->old_push(). Later, when the socket is close()d, vcc_destroy_socket() passes NULL skb to clip_push(), which calls clip_vcc->old_push(), triggering the infinite recursion. Let's prevent the second ioctl(ATMARP_MKIP) by checking vcc->user_back, which is allocated by the first call as clip_vcc. Note also that we use lock_sock() to prevent racy calls. [0]: BUG: TASK stack guard page was hit at ffffc9000d66fff8 (stack is ffffc9000d670000..ffffc9000d678000) Oops: stack guard page: 0000 [#1] SMP KASAN NOPTI CPU: 0 UID: 0 PID: 5322 Comm: syz.0.0 Not tainted 6.16.0-rc4-syzkaller #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 RIP: 0010:clip_push+0x5/0x720 net/atm/clip.c:191 Code: e0 8f aa 8c e8 1c ad 5b fa eb ae 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 <41> 57 41 56 41 55 41 54 53 48 83 ec 20 48 89 f3 49 89 fd 48 bd 00 RSP: 0018:ffffc9000d670000 EFLAGS: 00010246 RAX: 1ffff1100235a4a5 RBX: ffff888011ad2508 RCX: ffff8880003c0000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff888037f01000 RBP: dffffc0000000000 R08: ffffffff8fa104f7 R09: 1ffffffff1f4209e R10: dffffc0000000000 R11: ffffffff8a99b300 R12: ffffffff8a99b300 R13: ffff888037f01000 R14: ffff888011ad2500 R15: ffff888037f01578 FS: 000055557ab6d500(0000) GS:ffff88808d250000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc9000d66fff8 CR3: 0000000043172000 CR4: 0000000000352ef0 Call Trace: <TASK> clip_push+0x6dc/0x720 net/atm/clip.c:200 clip_push+0x6dc/0x720 net/atm/clip.c:200 clip_push+0x6dc/0x720 net/atm/clip.c:200 ... clip_push+0x6dc/0x720 net/atm/clip.c:200 clip_push+0x6dc/0x720 net/atm/clip.c:200 clip_push+0x6dc/0x720 net/atm/clip.c:200 vcc_destroy_socket net/atm/common.c:183 [inline] vcc_release+0x157/0x460 net/atm/common.c:205 __sock_release net/socket.c:647 [inline] sock_close+0xc0/0x240 net/socket.c:1391 __fput+0x449/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline] do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff31c98e929 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffb5aa1f78 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 0000000000012747 RCX: 00007ff31c98e929 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007ff31cbb7ba0 R08: 0000000000000001 R09: 0000000db5aa226f R10: 00007ff31c7ff030 R11: 0000000000000246 R12: 00007ff31cbb608c R13: 00007ff31cbb6080 R14: ffffffffffffffff R15: 00007fffb5aa2090 </TASK> Modules linked in:

In the Linux kernel, the following vulnerability has been resolved: ASoC: codecs: wcd9335: Fix missing free of regulator supplies Driver gets and enables all regulator supplies in probe path (wcd9335_parse_dt() and wcd9335_power_on_reset()), but does not cleanup in final error paths and in unbind (missing remove() callback). This leads to leaked memory and unbalanced regulator enable count during probe errors or unbind. Fix this by converting entire code into devm_regulator_bulk_get_enable() which also greatly simplifies the code.

NVIDIA GPU Display Driver for Windows and Linux contains a vulnerability where a user can cause an untrusted pointer dereference by executing a driver API. A successful exploit of this vulnerability might lead to denial of service, information disclosure, and data tampering.

In the Linux kernel, the following vulnerability has been resolved: usb: gadget : fix use-after-free in composite_dev_cleanup() 1. In func configfs_composite_bind() -> composite_os_desc_req_prepare(): if kmalloc fails, the pointer cdev->os_desc_req will be freed but not set to NULL. Then it will return a failure to the upper-level function. 2. in func configfs_composite_bind() -> composite_dev_cleanup(): it will checks whether cdev->os_desc_req is NULL. If it is not NULL, it will attempt to use it.This will lead to a use-after-free issue. BUG: KASAN: use-after-free in composite_dev_cleanup+0xf4/0x2c0 Read of size 8 at addr 0000004827837a00 by task init/1 CPU: 10 PID: 1 Comm: init Tainted: G O 5.10.97-oh #1 kasan_report+0x188/0x1cc __asan_load8+0xb4/0xbc composite_dev_cleanup+0xf4/0x2c0 configfs_composite_bind+0x210/0x7ac udc_bind_to_driver+0xb4/0x1ec usb_gadget_probe_driver+0xec/0x21c gadget_dev_desc_UDC_store+0x264/0x27c

In the Linux kernel, the following vulnerability has been resolved: vsock/vmci: Clear the vmci transport packet properly when initializing it In vmci_transport_packet_init memset the vmci_transport_packet before populating the fields to avoid any uninitialised data being left in the structure.

In the Linux kernel, the following vulnerability has been resolved: wifi: prevent A-MSDU attacks in mesh networks This patch is a mitigation to prevent the A-MSDU spoofing vulnerability for mesh networks. The initial update to the IEEE 802.11 standard, in response to the FragAttacks, missed this case (CVE-2025-27558). It can be considered a variant of CVE-2020-24588 but for mesh networks. This patch tries to detect if a standard MSDU was turned into an A-MSDU by an adversary. This is done by parsing a received A-MSDU as a standard MSDU, calculating the length of the Mesh Control header, and seeing if the 6 bytes after this header equal the start of an rfc1042 header. If equal, this is a strong indication of an ongoing attack attempt. This defense was tested with mac80211_hwsim against a mesh network that uses an empty Mesh Address Extension field, i.e., when four addresses are used, and when using a 12-byte Mesh Address Extension field, i.e., when six addresses are used. Functionality of normal MSDUs and A-MSDUs was also tested, and confirmed working, when using both an empty and 12-byte Mesh Address Extension field. It was also tested with mac80211_hwsim that A-MSDU attacks in non-mesh networks keep being detected and prevented. Note that the vulnerability being patched, and the defense being implemented, was also discussed in the following paper and in the following IEEE 802.11 presentation: https://papers.mathyvanhoef.com/wisec2025.pdf https://mentor.ieee.org/802.11/dcn/25/11-25-0949-00-000m-a-msdu-mesh-spoof-protection.docx

In the Linux kernel, the following vulnerability has been resolved: net: lan743x: fix potential out-of-bounds write in lan743x_ptp_io_event_clock_get() Before calling lan743x_ptp_io_event_clock_get(), the 'channel' value is checked against the maximum value of PCI11X1X_PTP_IO_MAX_CHANNELS(8). This seems correct and aligns with the PTP interrupt status register (PTP_INT_STS) specifications. However, lan743x_ptp_io_event_clock_get() writes to ptp->extts[] with only LAN743X_PTP_N_EXTTS(4) elements, using channel as an index: lan743x_ptp_io_event_clock_get(..., u8 channel,...) { ... /* Update Local timestamp */ extts = &ptp->extts[channel]; extts->ts.tv_sec = sec; ... } To avoid an out-of-bounds write and utilize all the supported GPIO inputs, set LAN743X_PTP_N_EXTTS to 8. Detected using the static analysis tool - Svace.

In the Linux kernel, the following vulnerability has been resolved: crypto: lzo - Fix compression buffer overrun Unlike the decompression code, the compression code in LZO never checked for output overruns. It instead assumes that the caller always provides enough buffer space, disregarding the buffer length provided by the caller. Add a safe compression interface that checks for the end of buffer before each write. Use the safe interface in crypto/lzo.

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: gadget: check that event count does not exceed event buffer length The event count is read from register DWC3_GEVNTCOUNT. There is a check for the count being zero, but not for exceeding the event buffer length. Check that event count does not exceed event buffer length, avoiding an out-of-bounds access when memcpy'ing the event. Crash log: Unable to handle kernel paging request at virtual address ffffffc0129be000 pc : __memcpy+0x114/0x180 lr : dwc3_check_event_buf+0xec/0x348 x3 : 0000000000000030 x2 : 000000000000dfc4 x1 : ffffffc0129be000 x0 : ffffff87aad60080 Call trace: __memcpy+0x114/0x180 dwc3_interrupt+0x24/0x34

In the Linux kernel, the following vulnerability has been resolved: fbcon: Make sure modelist not set on unregistered console It looks like attempting to write to the "store_modes" sysfs node will run afoul of unregistered consoles: UBSAN: array-index-out-of-bounds in drivers/video/fbdev/core/fbcon.c:122:28 index -1 is out of range for type 'fb_info *[32]' ... fbcon_info_from_console+0x192/0x1a0 drivers/video/fbdev/core/fbcon.c:122 fbcon_new_modelist+0xbf/0x2d0 drivers/video/fbdev/core/fbcon.c:3048 fb_new_modelist+0x328/0x440 drivers/video/fbdev/core/fbmem.c:673 store_modes+0x1c9/0x3e0 drivers/video/fbdev/core/fbsysfs.c:113 dev_attr_store+0x55/0x80 drivers/base/core.c:2439 static struct fb_info *fbcon_registered_fb[FB_MAX]; ... static signed char con2fb_map[MAX_NR_CONSOLES]; ... static struct fb_info *fbcon_info_from_console(int console) ... return fbcon_registered_fb[con2fb_map[console]]; If con2fb_map contains a -1 things go wrong here. Instead, return NULL, as callers of fbcon_info_from_console() are trying to compare against existing "info" pointers, so error handling should kick in correctly.

In the Linux kernel, the following vulnerability has been resolved: coresight: prevent deactivate active config while enabling the config While enable active config via cscfg_csdev_enable_active_config(), active config could be deactivated via configfs' sysfs interface. This could make UAF issue in below scenario: CPU0 CPU1 (sysfs enable) load module cscfg_load_config_sets() activate config. // sysfs (sys_active_cnt == 1) ... cscfg_csdev_enable_active_config() lock(csdev->cscfg_csdev_lock) // here load config activate by CPU1 unlock(csdev->cscfg_csdev_lock) deactivate config // sysfs (sys_activec_cnt == 0) cscfg_unload_config_sets() unload module // access to config_desc which freed // while unloading module. cscfg_csdev_enable_config To address this, use cscfg_config_desc's active_cnt as a reference count which will be holded when - activate the config. - enable the activated config. and put the module reference when config_active_cnt == 0.

In the Linux kernel, the following vulnerability has been resolved: ASoC: qcom: Fix sc7280 lpass potential buffer overflow Case values introduced in commit 5f78e1fb7a3e ("ASoC: qcom: Add driver support for audioreach solution") cause out of bounds access in arrays of sc7280 driver data (e.g. in case of RX_CODEC_DMA_RX_0 in sc7280_snd_hw_params()). Redefine LPASS_MAX_PORTS to consider the maximum possible port id for q6dsp as sc7280 driver utilizes some of those values. Found by Linux Verification Center (linuxtesting.org) with SVACE.

In the Linux kernel, the following vulnerability has been resolved: ipc: fix to protect IPCS lookups using RCU syzbot reported that it discovered a use-after-free vulnerability, [0] [0]: https://lore.kernel.org/all/67af13f8.050a0220.21dd3.0038.GAE@google.com/ idr_for_each() is protected by rwsem, but this is not enough. If it is not protected by RCU read-critical region, when idr_for_each() calls radix_tree_node_free() through call_rcu() to free the radix_tree_node structure, the node will be freed immediately, and when reading the next node in radix_tree_for_each_slot(), the already freed memory may be read. Therefore, we need to add code to make sure that idr_for_each() is protected within the RCU read-critical region when we call it in shm_destroy_orphaned().

In the Linux kernel, the following vulnerability has been resolved: ksmbd: prevent out-of-bounds stream writes by validating *pos ksmbd_vfs_stream_write() did not validate whether the write offset (*pos) was within the bounds of the existing stream data length (v_len). If *pos was greater than or equal to v_len, this could lead to an out-of-bounds memory write. This patch adds a check to ensure *pos is less than v_len before proceeding. If the condition fails, -EINVAL is returned.

In the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc: fix double-free on mc_dev The blamed commit tried to simplify how the deallocations are done but, in the process, introduced a double-free on the mc_dev variable. In case the MC device is a DPRC, a new mc_bus is allocated and the mc_dev variable is just a reference to one of its fields. In this circumstance, on the error path only the mc_bus should be freed. This commit introduces back the following checkpatch warning which is a false-positive. WARNING: kfree(NULL) is safe and this check is probably not required + if (mc_bus) + kfree(mc_bus);

In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a UAF vulnerability in class handling This patch fixes a Use-After-Free vulnerability in the HFSC qdisc class handling. The issue occurs due to a time-of-check/time-of-use condition in hfsc_change_class() when working with certain child qdiscs like netem or codel. The vulnerability works as follows: 1. hfsc_change_class() checks if a class has packets (q.qlen != 0) 2. It then calls qdisc_peek_len(), which for certain qdiscs (e.g., codel, netem) might drop packets and empty the queue 3. The code continues assuming the queue is still non-empty, adding the class to vttree 4. This breaks HFSC scheduler assumptions that only non-empty classes are in vttree 5. Later, when the class is destroyed, this can lead to a Use-After-Free The fix adds a second queue length check after qdisc_peek_len() to verify the queue wasn't emptied.

In the Linux kernel, the following vulnerability has been resolved: net_sched: ets: Fix double list add in class with netem as child qdisc As described in Gerrard's report [1], there are use cases where a netem child qdisc will make the parent qdisc's enqueue callback reentrant. In the case of ets, there won't be a UAF, but the code will add the same classifier to the list twice, which will cause memory corruption. In addition to checking for qlen being zero, this patch checks whether the class was already added to the active_list (cl_is_active) before doing the addition to cater for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

In the Linux kernel, the following vulnerability has been resolved: bpf: Avoid __bpf_prog_ret0_warn when jit fails syzkaller reported an issue: WARNING: CPU: 3 PID: 217 at kernel/bpf/core.c:2357 __bpf_prog_ret0_warn+0xa/0x20 kernel/bpf/core.c:2357 Modules linked in: CPU: 3 UID: 0 PID: 217 Comm: kworker/u32:6 Not tainted 6.15.0-rc4-syzkaller-00040-g8bac8898fe39 RIP: 0010:__bpf_prog_ret0_warn+0xa/0x20 kernel/bpf/core.c:2357 Call Trace: <TASK> bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline] __bpf_prog_run include/linux/filter.h:718 [inline] bpf_prog_run include/linux/filter.h:725 [inline] cls_bpf_classify+0x74a/0x1110 net/sched/cls_bpf.c:105 ... When creating bpf program, 'fp->jit_requested' depends on bpf_jit_enable. This issue is triggered because of CONFIG_BPF_JIT_ALWAYS_ON is not set and bpf_jit_enable is set to 1, causing the arch to attempt JIT the prog, but jit failed due to FAULT_INJECTION. As a result, incorrectly treats the program as valid, when the program runs it calls `__bpf_prog_ret0_warn` and triggers the WARN_ON_ONCE(1).

In the Linux kernel, the following vulnerability has been resolved: tipc: Fix use-after-free in tipc_conn_close(). syzbot reported a null-ptr-deref in tipc_conn_close() during netns dismantle. [0] tipc_topsrv_stop() iterates tipc_net(net)->topsrv->conn_idr and calls tipc_conn_close() for each tipc_conn. The problem is that tipc_conn_close() is called after releasing the IDR lock. At the same time, there might be tipc_conn_recv_work() running and it could call tipc_conn_close() for the same tipc_conn and release its last ->kref. Once we release the IDR lock in tipc_topsrv_stop(), there is no guarantee that the tipc_conn is alive. Let's hold the ref before releasing the lock and put the ref after tipc_conn_close() in tipc_topsrv_stop(). [0]: BUG: KASAN: use-after-free in tipc_conn_close+0x122/0x140 net/tipc/topsrv.c:165 Read of size 8 at addr ffff888099305a08 by task kworker/u4:3/435 CPU: 0 PID: 435 Comm: kworker/u4:3 Not tainted 4.19.204-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1fc/0x2ef lib/dump_stack.c:118 print_address_description.cold+0x54/0x219 mm/kasan/report.c:256 kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354 kasan_report mm/kasan/report.c:412 [inline] __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433 tipc_conn_close+0x122/0x140 net/tipc/topsrv.c:165 tipc_topsrv_stop net/tipc/topsrv.c:701 [inline] tipc_topsrv_exit_net+0x27b/0x5c0 net/tipc/topsrv.c:722 ops_exit_list+0xa5/0x150 net/core/net_namespace.c:153 cleanup_net+0x3b4/0x8b0 net/core/net_namespace.c:553 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Allocated by task 23: kmem_cache_alloc_trace+0x12f/0x380 mm/slab.c:3625 kmalloc include/linux/slab.h:515 [inline] kzalloc include/linux/slab.h:709 [inline] tipc_conn_alloc+0x43/0x4f0 net/tipc/topsrv.c:192 tipc_topsrv_accept+0x1b5/0x280 net/tipc/topsrv.c:470 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Freed by task 23: __cache_free mm/slab.c:3503 [inline] kfree+0xcc/0x210 mm/slab.c:3822 tipc_conn_kref_release net/tipc/topsrv.c:150 [inline] kref_put include/linux/kref.h:70 [inline] conn_put+0x2cd/0x3a0 net/tipc/topsrv.c:155 process_one_work+0x864/0x1570 kernel/workqueue.c:2153 worker_thread+0x64c/0x1130 kernel/workqueue.c:2296 kthread+0x33f/0x460 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 The buggy address belongs to the object at ffff888099305a00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 8 bytes inside of 512-byte region [ffff888099305a00, ffff888099305c00) The buggy address belongs to the page: page:ffffea000264c140 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0 flags: 0xfff00000000100(slab) raw: 00fff00000000100 ffffea00028b6b88 ffffea0002cd2b08 ffff88813bff0940 raw: 0000000000000000 ffff888099305000 0000000100000006 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888099305900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888099305980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888099305a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888099305a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888099305b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

In the Linux kernel, the following vulnerability has been resolved: exfat: fix double free in delayed_free The double free could happen in the following path. exfat_create_upcase_table() exfat_create_upcase_table() : return error exfat_free_upcase_table() : free ->vol_utbl exfat_load_default_upcase_table : return error exfat_kill_sb() delayed_free() exfat_free_upcase_table() <--------- double free This patch set ->vol_util as NULL after freeing it.

In the Linux kernel, the following vulnerability has been resolved: KVM: arm64: Tear down vGIC on failed vCPU creation If kvm_arch_vcpu_create() fails to share the vCPU page with the hypervisor, we propagate the error back to the ioctl but leave the vGIC vCPU data initialised. Note only does this leak the corresponding memory when the vCPU is destroyed but it can also lead to use-after-free if the redistributor device handling tries to walk into the vCPU. Add the missing cleanup to kvm_arch_vcpu_create(), ensuring that the vGIC vCPU structures are destroyed on error.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix potential use-after-free in oplock/lease break ack If ksmbd_iov_pin_rsp return error, use-after-free can happen by accessing opinfo->state and opinfo_put and ksmbd_fd_put could called twice.

In the Linux kernel, the following vulnerability has been resolved: vxlan: vnifilter: Fix unlocked deletion of default FDB entry When a VNI is deleted from a VXLAN device in 'vnifilter' mode, the FDB entry associated with the default remote (assuming one was configured) is deleted without holding the hash lock. This is wrong and will result in a warning [1] being generated by the lockdep annotation that was added by commit ebe642067455 ("vxlan: Create wrappers for FDB lookup"). Reproducer: # ip link add vx0 up type vxlan dstport 4789 external vnifilter local 192.0.2.1 # bridge vni add vni 10010 remote 198.51.100.1 dev vx0 # bridge vni del vni 10010 dev vx0 Fix by acquiring the hash lock before the deletion and releasing it afterwards. Blame the original commit that introduced the issue rather than the one that exposed it. [1] WARNING: CPU: 3 PID: 392 at drivers/net/vxlan/vxlan_core.c:417 vxlan_find_mac+0x17f/0x1a0 [...] RIP: 0010:vxlan_find_mac+0x17f/0x1a0 [...] Call Trace: <TASK> __vxlan_fdb_delete+0xbe/0x560 vxlan_vni_delete_group+0x2ba/0x940 vxlan_vni_del.isra.0+0x15f/0x580 vxlan_process_vni_filter+0x38b/0x7b0 vxlan_vnifilter_process+0x3bb/0x510 rtnetlink_rcv_msg+0x2f7/0xb70 netlink_rcv_skb+0x131/0x360 netlink_unicast+0x426/0x710 netlink_sendmsg+0x75a/0xc20 __sock_sendmsg+0xc1/0x150 ____sys_sendmsg+0x5aa/0x7b0 ___sys_sendmsg+0xfc/0x180 __sys_sendmsg+0x121/0x1b0 do_syscall_64+0xbb/0x1d0 entry_SYSCALL_64_after_hwframe+0x4b/0x53

In the Linux kernel, the following vulnerability has been resolved: fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass Export anon_inode_make_secure_inode() to allow KVM guest_memfd to create anonymous inodes with proper security context. This replaces the current pattern of calling alloc_anon_inode() followed by inode_init_security_anon() for creating security context manually. This change also fixes a security regression in secretmem where the S_PRIVATE flag was not cleared after alloc_anon_inode(), causing LSM/SELinux checks to be bypassed for secretmem file descriptors. As guest_memfd currently resides in the KVM module, we need to export this symbol for use outside the core kernel. In the future, guest_memfd might be moved to core-mm, at which point the symbols no longer would have to be exported. When/if that happens is still unclear.

In the Linux kernel, the following vulnerability has been resolved: wifi: p54: prevent buffer-overflow in p54_rx_eeprom_readback() Robert Morris reported: |If a malicious USB device pretends to be an Intersil p54 wifi |interface and generates an eeprom_readback message with a large |eeprom->v1.len, p54_rx_eeprom_readback() will copy data from the |message beyond the end of priv->eeprom. | |static void p54_rx_eeprom_readback(struct p54_common *priv, | struct sk_buff *skb) |{ | struct p54_hdr *hdr = (struct p54_hdr *) skb->data; | struct p54_eeprom_lm86 *eeprom = (struct p54_eeprom_lm86 *) hdr->data; | | if (priv->fw_var >= 0x509) { | memcpy(priv->eeprom, eeprom->v2.data, | le16_to_cpu(eeprom->v2.len)); | } else { | memcpy(priv->eeprom, eeprom->v1.data, | le16_to_cpu(eeprom->v1.len)); | } | [...] The eeprom->v{1,2}.len is set by the driver in p54_download_eeprom(). The device is supposed to provide the same length back to the driver. But yes, it's possible (like shown in the report) to alter the value to something that causes a crash/panic due to overrun. This patch addresses the issue by adding the size to the common device context, so p54_rx_eeprom_readback no longer relies on possibly tampered values... That said, it also checks if the "firmware" altered the value and no longer copies them. The one, small saving grace is: Before the driver tries to read the eeprom, it needs to upload >a< firmware. the vendor firmware has a proprietary license and as a reason, it is not present on most distributions by default.

In the Linux kernel, the following vulnerability has been resolved: drm/amdkfd: Fix mode1 reset crash issue If HW scheduler hangs and mode1 reset is used to recover GPU, KFD signal user space to abort the processes. After process abort exit, user queues still use the GPU to access system memory before h/w is reset while KFD cleanup worker free system memory and free VRAM. There is use-after-free race bug that KFD allocate and reuse the freed system memory, and user queue write to the same system memory to corrupt the data structure and cause driver crash. To fix this race, KFD cleanup worker terminate user queues, then flush reset_domain wq to wait for any GPU ongoing reset complete, and then free outstanding BOs.

In the Linux kernel, the following vulnerability has been resolved: virtio-net: ensure the received length does not exceed allocated size In xdp_linearize_page, when reading the following buffers from the ring, we forget to check the received length with the true allocate size. This can lead to an out-of-bound read. This commit adds that missing check.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Fix UAF on mgmt_remove_adv_monitor_complete This reworks MGMT_OP_REMOVE_ADV_MONITOR to not use mgmt_pending_add to avoid crashes like bellow: ================================================================== BUG: KASAN: slab-use-after-free in mgmt_remove_adv_monitor_complete+0xe5/0x540 net/bluetooth/mgmt.c:5406 Read of size 8 at addr ffff88801c53f318 by task kworker/u5:5/5341 CPU: 0 UID: 0 PID: 5341 Comm: kworker/u5:5 Not tainted 6.15.0-syzkaller-10402-g4cb6c8af8591 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: hci0 hci_cmd_sync_work Call Trace: <TASK> dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xd2/0x2b0 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 mgmt_remove_adv_monitor_complete+0xe5/0x540 net/bluetooth/mgmt.c:5406 hci_cmd_sync_work+0x261/0x3a0 net/bluetooth/hci_sync.c:334 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 </TASK> Allocated by task 5987: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] mgmt_pending_new+0x65/0x240 net/bluetooth/mgmt_util.c:252 mgmt_pending_add+0x34/0x120 net/bluetooth/mgmt_util.c:279 remove_adv_monitor+0x103/0x1b0 net/bluetooth/mgmt.c:5454 hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719 hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x219/0x270 net/socket.c:727 sock_write_iter+0x258/0x330 net/socket.c:1131 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x548/0xa90 fs/read_write.c:686 ksys_write+0x145/0x250 fs/read_write.c:738 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 5989: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x18e/0x440 mm/slub.c:4841 mgmt_pending_foreach+0xc9/0x120 net/bluetooth/mgmt_util.c:242 mgmt_index_removed+0x10d/0x2f0 net/bluetooth/mgmt.c:9366 hci_sock_bind+0xbe9/0x1000 net/bluetooth/hci_sock.c:1314 __sys_bind_socket net/socket.c:1810 [inline] __sys_bind+0x2c3/0x3e0 net/socket.c:1841 __do_sys_bind net/socket.c:1846 [inline] __se_sys_bind net/socket.c:1844 [inline] __x64_sys_bind+0x7a/0x90 net/socket.c:1844 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f

In the Linux kernel, the following vulnerability has been resolved: net/sched: Always pass notifications when child class becomes empty Certain classful qdiscs may invoke their classes' dequeue handler on an enqueue operation. This may unexpectedly empty the child qdisc and thus make an in-flight class passive via qlen_notify(). Most qdiscs do not expect such behaviour at this point in time and may re-activate the class eventually anyways which will lead to a use-after-free. The referenced fix commit attempted to fix this behavior for the HFSC case by moving the backlog accounting around, though this turned out to be incomplete since the parent's parent may run into the issue too. The following reproducer demonstrates this use-after-free: tc qdisc add dev lo root handle 1: drr tc filter add dev lo parent 1: basic classid 1:1 tc class add dev lo parent 1: classid 1:1 drr tc qdisc add dev lo parent 1:1 handle 2: hfsc def 1 tc class add dev lo parent 2: classid 2:1 hfsc rt m1 8 d 1 m2 0 tc qdisc add dev lo parent 2:1 handle 3: netem tc qdisc add dev lo parent 3:1 handle 4: blackhole echo 1 | socat -u STDIN UDP4-DATAGRAM:127.0.0.1:8888 tc class delete dev lo classid 1:1 echo 1 | socat -u STDIN UDP4-DATAGRAM:127.0.0.1:8888 Since backlog accounting issues leading to a use-after-frees on stale class pointers is a recurring pattern at this point, this patch takes a different approach. Instead of trying to fix the accounting, the patch ensures that qdisc_tree_reduce_backlog always calls qlen_notify when the child qdisc is empty. This solves the problem because deletion of qdiscs always involves a call to qdisc_reset() and / or qdisc_purge_queue() which ultimately resets its qlen to 0 thus causing the following qdisc_tree_reduce_backlog() to report to the parent. Note that this may call qlen_notify on passive classes multiple times. This is not a problem after the recent patch series that made all the classful qdiscs qlen_notify() handlers idempotent.