A flaw was found in the crypto subsystem of the Linux kernel before version kernel-4.15-rc4. The "null skcipher" was being dropped when each af_alg_ctx was freed instead of when the aead_tfm was freed. This can cause the null skcipher to be freed while it is still in use leading to a local user being able to crash the system or possibly escalate privileges.

An issue was discovered in the Linux kernel through 4.17.10. There is a use-after-free in try_merge_free_space() when mounting a crafted btrfs image, because of a lack of chunk type flag checks in btrfs_check_chunk_valid in fs/btrfs/volumes.c.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free in session logoff The sess->user object can currently be in use by another thread, for example if another connection has sent a session setup request to bind to the session being free'd. The handler for that connection could be in the smb2_sess_setup function which makes use of sess->user.

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: 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: scsi: mpi3mr: Synchronous access b/w reset and tm thread for reply queue When the task management thread processes reply queues while the reset thread resets them, the task management thread accesses an invalid queue ID (0xFFFF), set by the reset thread, which points to unallocated memory, causing a crash. Add flag 'io_admin_reset_sync' to synchronize access between the reset, I/O, and admin threads. Before a reset, the reset handler sets this flag to block I/O and admin processing threads. If any thread bypasses the initial check, the reset thread waits up to 10 seconds for processing to finish. If the wait exceeds 10 seconds, the controller is marked as unrecoverable.

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix a use-after-free in r535_gsp_rpc_push() The RPC container is released after being passed to r535_gsp_rpc_send(). When sending the initial fragment of a large RPC and passing the caller's RPC container, the container will be freed prematurely. Subsequent attempts to send remaining fragments will therefore result in a use-after-free. Allocate a temporary RPC container for holding the initial fragment of a large RPC when sending. Free the caller's container when all fragments are successfully sent. [ Rebase onto Blackwell changes. - Danilo ]

In the Linux kernel, the following vulnerability has been resolved: drm/imagination: take paired job reference For paired jobs, have the fragment job take a reference on the geometry job, so that the geometry job cannot be freed until the fragment job has finished with it. The geometry job structure is accessed when the fragment job is being prepared by the GPU scheduler. Taking the reference prevents the geometry job being freed until the fragment job no longer requires it. Fixes a use after free bug detected by KASAN: [ 124.256386] BUG: KASAN: slab-use-after-free in pvr_queue_prepare_job+0x108/0x868 [powervr] [ 124.264893] Read of size 1 at addr ffff0000084cb960 by task kworker/u16:4/63

In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a UAF vulnerability in class with netem as child qdisc As described in Gerrard's report [1], we have a UAF case when an hfsc class has a netem child qdisc. The crux of the issue is that hfsc is assuming that checking for cl->qdisc->q.qlen == 0 guarantees that it hasn't inserted the class in the vttree or eltree (which is not true for the netem duplicate case). This patch checks the n_active class variable to make sure that the code won't insert the class in the vttree or eltree twice, catering for the reentrant case. [1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/

A flaw was found in the Linux Kernel where an attacker may be able to have an uncontrolled read to kernel-memory from within a vm guest. A race condition between connect() and close() function may allow an attacker using the AF_VSOCK protocol to gather a 4 byte information leak or possibly intercept or corrupt AF_VSOCK messages destined to other clients.

In the Linux kernel, the following vulnerability has been resolved: net/sched: fix use-after-free in taprio_dev_notifier Since taprio’s taprio_dev_notifier() isn’t protected by an RCU read-side critical section, a race with advance_sched() can lead to a use-after-free. Adding rcu_read_lock() inside taprio_dev_notifier() prevents this.

In the Linux kernel, the following vulnerability has been resolved: net_sched: hfsc: Fix a potential UAF in hfsc_dequeue() too Similarly to the previous patch, we need to safe guard hfsc_dequeue() too. But for this one, we don't have a reliable reproducer.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Fix slab-use-after-free in hdcp The HDCP code in amdgpu_dm_hdcp.c copies pointers to amdgpu_dm_connector objects without incrementing the kref reference counts. When using a USB-C dock, and the dock is unplugged, the corresponding amdgpu_dm_connector objects are freed, creating dangling pointers in the HDCP code. When the dock is plugged back, the dangling pointers are dereferenced, resulting in a slab-use-after-free: [ 66.775837] BUG: KASAN: slab-use-after-free in event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.776171] Read of size 4 at addr ffff888127804120 by task kworker/0:1/10 [ 66.776179] CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.14.0-rc7-00180-g54505f727a38-dirty #233 [ 66.776183] Hardware name: HP HP Pavilion Aero Laptop 13-be0xxx/8916, BIOS F.17 12/18/2024 [ 66.776186] Workqueue: events event_property_validate [amdgpu] [ 66.776494] Call Trace: [ 66.776496] <TASK> [ 66.776497] dump_stack_lvl+0x70/0xa0 [ 66.776504] print_report+0x175/0x555 [ 66.776507] ? __virt_addr_valid+0x243/0x450 [ 66.776510] ? kasan_complete_mode_report_info+0x66/0x1c0 [ 66.776515] kasan_report+0xeb/0x1c0 [ 66.776518] ? event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.776819] ? event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.777121] __asan_report_load4_noabort+0x14/0x20 [ 66.777124] event_property_validate+0x42f/0x6c0 [amdgpu] [ 66.777342] ? __lock_acquire+0x6b40/0x6b40 [ 66.777347] ? enable_assr+0x250/0x250 [amdgpu] [ 66.777571] process_one_work+0x86b/0x1510 [ 66.777575] ? pwq_dec_nr_in_flight+0xcf0/0xcf0 [ 66.777578] ? assign_work+0x16b/0x280 [ 66.777580] ? lock_is_held_type+0xa3/0x130 [ 66.777583] worker_thread+0x5c0/0xfa0 [ 66.777587] ? process_one_work+0x1510/0x1510 [ 66.777588] kthread+0x3a2/0x840 [ 66.777591] ? kthread_is_per_cpu+0xd0/0xd0 [ 66.777594] ? trace_hardirqs_on+0x4f/0x60 [ 66.777597] ? _raw_spin_unlock_irq+0x27/0x60 [ 66.777599] ? calculate_sigpending+0x77/0xa0 [ 66.777602] ? kthread_is_per_cpu+0xd0/0xd0 [ 66.777605] ret_from_fork+0x40/0x90 [ 66.777607] ? kthread_is_per_cpu+0xd0/0xd0 [ 66.777609] ret_from_fork_asm+0x11/0x20 [ 66.777614] </TASK> [ 66.777643] Allocated by task 10: [ 66.777646] kasan_save_stack+0x39/0x60 [ 66.777649] kasan_save_track+0x14/0x40 [ 66.777652] kasan_save_alloc_info+0x37/0x50 [ 66.777655] __kasan_kmalloc+0xbb/0xc0 [ 66.777658] __kmalloc_cache_noprof+0x1c8/0x4b0 [ 66.777661] dm_dp_add_mst_connector+0xdd/0x5c0 [amdgpu] [ 66.777880] drm_dp_mst_port_add_connector+0x47e/0x770 [drm_display_helper] [ 66.777892] drm_dp_send_link_address+0x1554/0x2bf0 [drm_display_helper] [ 66.777901] drm_dp_check_and_send_link_address+0x187/0x1f0 [drm_display_helper] [ 66.777909] drm_dp_mst_link_probe_work+0x2b8/0x410 [drm_display_helper] [ 66.777917] process_one_work+0x86b/0x1510 [ 66.777919] worker_thread+0x5c0/0xfa0 [ 66.777922] kthread+0x3a2/0x840 [ 66.777925] ret_from_fork+0x40/0x90 [ 66.777927] ret_from_fork_asm+0x11/0x20 [ 66.777932] Freed by task 1713: [ 66.777935] kasan_save_stack+0x39/0x60 [ 66.777938] kasan_save_track+0x14/0x40 [ 66.777940] kasan_save_free_info+0x3b/0x60 [ 66.777944] __kasan_slab_free+0x52/0x70 [ 66.777946] kfree+0x13f/0x4b0 [ 66.777949] dm_dp_mst_connector_destroy+0xfa/0x150 [amdgpu] [ 66.778179] drm_connector_free+0x7d/0xb0 [ 66.778184] drm_mode_object_put.part.0+0xee/0x160 [ 66.778188] drm_mode_object_put+0x37/0x50 [ 66.778191] drm_atomic_state_default_clear+0x220/0xd60 [ 66.778194] __drm_atomic_state_free+0x16e/0x2a0 [ 66.778197] drm_mode_atomic_ioctl+0x15ed/0x2ba0 [ 66.778200] drm_ioctl_kernel+0x17a/0x310 [ 66.778203] drm_ioctl+0x584/0xd10 [ 66.778206] amdgpu_drm_ioctl+0xd2/0x1c0 [amdgpu] [ 66.778375] __x64_sys_ioctl+0x139/0x1a0 [ 66.778378] x64_sys_call+0xee7/0xfb0 [ 66.778381] ---truncated---

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: binder: fix yet another UAF in binder_devices Commit e77aff5528a18 ("binderfs: fix use-after-free in binder_devices") addressed a use-after-free where devices could be released without first being removed from the binder_devices list. However, there is a similar path in binder_free_proc() that was missed: ================================================================== BUG: KASAN: slab-use-after-free in binder_remove_device+0xd4/0x100 Write of size 8 at addr ffff0000c773b900 by task umount/467 CPU: 12 UID: 0 PID: 467 Comm: umount Not tainted 6.15.0-rc7-00138-g57483a362741 #9 PREEMPT Hardware name: linux,dummy-virt (DT) Call trace: binder_remove_device+0xd4/0x100 binderfs_evict_inode+0x230/0x2f0 evict+0x25c/0x5dc iput+0x304/0x480 dentry_unlink_inode+0x208/0x46c __dentry_kill+0x154/0x530 [...] Allocated by task 463: __kmalloc_cache_noprof+0x13c/0x324 binderfs_binder_device_create.isra.0+0x138/0xa60 binder_ctl_ioctl+0x1ac/0x230 [...] Freed by task 215: kfree+0x184/0x31c binder_proc_dec_tmpref+0x33c/0x4ac binder_deferred_func+0xc10/0x1108 process_one_work+0x520/0xba4 [...] ================================================================== Call binder_remove_device() within binder_free_proc() to ensure the device is removed from the binder_devices list before being kfreed.

In the Linux kernel, the following vulnerability has been resolved: iio: accel: fxls8962af: Fix use after free in fxls8962af_fifo_flush fxls8962af_fifo_flush() uses indio_dev->active_scan_mask (with iio_for_each_active_channel()) without making sure the indio_dev stays in buffer mode. There is a race if indio_dev exits buffer mode in the middle of the interrupt that flushes the fifo. Fix this by calling synchronize_irq() to ensure that no interrupt is currently running when disabling buffer mode. Unable to handle kernel NULL pointer dereference at virtual address 00000000 when read [...] _find_first_bit_le from fxls8962af_fifo_flush+0x17c/0x290 fxls8962af_fifo_flush from fxls8962af_interrupt+0x80/0x178 fxls8962af_interrupt from irq_thread_fn+0x1c/0x7c irq_thread_fn from irq_thread+0x110/0x1f4 irq_thread from kthread+0xe0/0xfc kthread from ret_from_fork+0x14/0x2c

In the Linux kernel, the following vulnerability has been resolved: rose: fix dangling neighbour pointers in rose_rt_device_down() There are two bugs in rose_rt_device_down() that can cause use-after-free: 1. The loop bound `t->count` is modified within the loop, which can cause the loop to terminate early and miss some entries. 2. When removing an entry from the neighbour array, the subsequent entries are moved up to fill the gap, but the loop index `i` is still incremented, causing the next entry to be skipped. For example, if a node has three neighbours (A, A, B) with count=3 and A is being removed, the second A is not checked. i=0: (A, A, B) -> (A, B) with count=2 ^ checked i=1: (A, B) -> (A, B) with count=2 ^ checked (B, not A!) i=2: (doesn't occur because i < count is false) This leaves the second A in the array with count=2, but the rose_neigh structure has been freed. Code that accesses these entries assumes that the first `count` entries are valid pointers, causing a use-after-free when it accesses the dangling pointer. Fix both issues by iterating over the array in reverse order with a fixed loop bound. This ensures that all entries are examined and that the removal of an entry doesn't affect subsequent iterations.

In the Linux kernel, the following vulnerability has been resolved: ftrace: Fix UAF when lookup kallsym after ftrace disabled The following issue happens with a buggy module: BUG: unable to handle page fault for address: ffffffffc05d0218 PGD 1bd66f067 P4D 1bd66f067 PUD 1bd671067 PMD 101808067 PTE 0 Oops: Oops: 0000 [#1] SMP KASAN PTI Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS RIP: 0010:sized_strscpy+0x81/0x2f0 RSP: 0018:ffff88812d76fa08 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffffc0601010 RCX: dffffc0000000000 RDX: 0000000000000038 RSI: dffffc0000000000 RDI: ffff88812608da2d RBP: 8080808080808080 R08: ffff88812608da2d R09: ffff88812608da68 R10: ffff88812608d82d R11: ffff88812608d810 R12: 0000000000000038 R13: ffff88812608da2d R14: ffffffffc05d0218 R15: fefefefefefefeff FS: 00007fef552de740(0000) GS:ffff8884251c7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffc05d0218 CR3: 00000001146f0000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ftrace_mod_get_kallsym+0x1ac/0x590 update_iter_mod+0x239/0x5b0 s_next+0x5b/0xa0 seq_read_iter+0x8c9/0x1070 seq_read+0x249/0x3b0 proc_reg_read+0x1b0/0x280 vfs_read+0x17f/0x920 ksys_read+0xf3/0x1c0 do_syscall_64+0x5f/0x2e0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The above issue may happen as follows: (1) Add kprobe tracepoint; (2) insmod test.ko; (3) Module triggers ftrace disabled; (4) rmmod test.ko; (5) cat /proc/kallsyms; --> Will trigger UAF as test.ko already removed; ftrace_mod_get_kallsym() ... strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); ... The problem is when a module triggers an issue with ftrace and sets ftrace_disable. The ftrace_disable is set when an anomaly is discovered and to prevent any more damage, ftrace stops all text modification. The issue that happened was that the ftrace_disable stops more than just the text modification. When a module is loaded, its init functions can also be traced. Because kallsyms deletes the init functions after a module has loaded, ftrace saves them when the module is loaded and function tracing is enabled. This allows the output of the function trace to show the init function names instead of just their raw memory addresses. When a module is removed, ftrace_release_mod() is called, and if ftrace_disable is set, it just returns without doing anything more. The problem here is that it leaves the mod_list still around and if kallsyms is called, it will call into this code and access the module memory that has already been freed as it will return: strscpy(module_name, mod_map->mod->name, MODULE_NAME_LEN); Where the "mod" no longer exists and triggers a UAF bug.

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: sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue() When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the child qdisc's peek() operation before incrementing sch->q.qlen and sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may trigger an immediate dequeue and potential packet drop. In such cases, qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog have not yet been updated, leading to inconsistent queue accounting. This can leave an empty HFSC class in the active list, causing further consequences like use-after-free. This patch fixes the bug by moving the increment of sch->q.qlen and sch->qstats.backlog before the call to the child qdisc's peek() operation. This ensures that queue length and backlog are always accurate when packet drops or dequeues are triggered during the peek.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: hci_core: Fix use-after-free in vhci_flush() syzbot reported use-after-free in vhci_flush() without repro. [0] From the splat, a thread close()d a vhci file descriptor while its device was being used by iotcl() on another thread. Once the last fd refcnt is released, vhci_release() calls hci_unregister_dev(), hci_free_dev(), and kfree() for struct vhci_data, which is set to hci_dev->dev->driver_data. The problem is that there is no synchronisation after unlinking hdev from hci_dev_list in hci_unregister_dev(). There might be another thread still accessing the hdev which was fetched before the unlink operation. We can use SRCU for such synchronisation. Let's run hci_dev_reset() under SRCU and wait for its completion in hci_unregister_dev(). Another option would be to restore hci_dev->destruct(), which was removed in commit 587ae086f6e4 ("Bluetooth: Remove unused hci-destruct cb"). However, this would not be a good solution, as we should not run hci_unregister_dev() while there are in-flight ioctl() requests, which could lead to another data-race KCSAN splat. Note that other drivers seem to have the same problem, for exmaple, virtbt_remove(). [0]: BUG: KASAN: slab-use-after-free in skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline] BUG: KASAN: slab-use-after-free in skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937 Read of size 8 at addr ffff88807cb8d858 by task syz.1.219/6718 CPU: 1 UID: 0 PID: 6718 Comm: syz.1.219 Not tainted 6.16.0-rc1-syzkaller-00196-g08207f42d3ff #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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 skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline] skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937 skb_queue_purge include/linux/skbuff.h:3368 [inline] vhci_flush+0x44/0x50 drivers/bluetooth/hci_vhci.c:69 hci_dev_do_reset net/bluetooth/hci_core.c:552 [inline] hci_dev_reset+0x420/0x5c0 net/bluetooth/hci_core.c:592 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893 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 RIP: 0033:0x7fcf5b98e929 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:00007fcf5c7b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fcf5bbb6160 RCX: 00007fcf5b98e929 RDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000009 RBP: 00007fcf5ba10b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fcf5bbb6160 R15: 00007ffd6353d528 </TASK> Allocated by task 6535: 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:4359 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] vhci_open+0x57/0x360 drivers/bluetooth/hci_vhci.c:635 misc_open+0x2bc/0x330 drivers/char/misc.c:161 chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414 do_dentry_open+0xdf0/0x1970 fs/open.c:964 vfs_open+0x3b/0x340 fs/open.c:1094 do_open fs/namei.c:3887 [inline] path_openat+0x2ee5/0x3830 fs/name ---truncated---

In the Linux kernel, the following vulnerability has been resolved: media: vidtv: Terminating the subsequent process of initialization failure syzbot reported a slab-use-after-free Read in vidtv_mux_init. [1] After PSI initialization fails, the si member is accessed again, resulting in this uaf. After si initialization fails, the subsequent process needs to be exited. [1] BUG: KASAN: slab-use-after-free in vidtv_mux_pid_ctx_init drivers/media/test-drivers/vidtv/vidtv_mux.c:78 [inline] BUG: KASAN: slab-use-after-free in vidtv_mux_init+0xac2/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:524 Read of size 8 at addr ffff88802fa42acc by task syz.2.37/6059 CPU: 0 UID: 0 PID: 6059 Comm: syz.2.37 Not tainted 6.14.0-rc5-syzkaller #0 Hardware name: Google Compute Engine, BIOS Google 02/12/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xc3/0x670 mm/kasan/report.c:521 kasan_report+0xd9/0x110 mm/kasan/report.c:634 vidtv_mux_pid_ctx_init drivers/media/test-drivers/vidtv/vidtv_mux.c:78 vidtv_mux_init+0xac2/0xbe0 drivers/media/test-drivers/vidtv/vidtv_mux.c:524 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 vidtv_start_feed drivers/media/test-drivers/vidtv/vidtv_bridge.c:239 dmx_section_feed_start_filtering drivers/media/dvb-core/dvb_demux.c:973 dvb_dmxdev_feed_start drivers/media/dvb-core/dmxdev.c:508 [inline] dvb_dmxdev_feed_restart.isra.0 drivers/media/dvb-core/dmxdev.c:537 dvb_dmxdev_filter_stop+0x2b4/0x3a0 drivers/media/dvb-core/dmxdev.c:564 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline] dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246 __fput+0x3ff/0xb70 fs/file_table.c:464 task_work_run+0x14e/0x250 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0xad8/0x2d70 kernel/exit.c:938 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 __do_sys_exit_group kernel/exit.c:1098 [inline] __se_sys_exit_group kernel/exit.c:1096 [inline] __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f871d58d169 Code: Unable to access opcode bytes at 0x7f871d58d13f. RSP: 002b:00007fff4b19a788 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f871d58d169 RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fff4b19a7ec R08: 0000000b4b19a87f R09: 00000000000927c0 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000003 R13: 00000000000927c0 R14: 000000000001d553 R15: 00007fff4b19a840 </TASK> Allocated by task 6059: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kmalloc_noprof include/linux/slab.h:901 [inline] kzalloc_noprof include/linux/slab.h:1037 [inline] vidtv_psi_pat_table_init drivers/media/test-drivers/vidtv/vidtv_psi.c:970 vidtv_channel_si_init drivers/media/test-drivers/vidtv/vidtv_channel.c:423 vidtv_mux_init drivers/media/test-drivers/vidtv/vidtv_mux.c:519 vidtv_start_streaming drivers/media/test-drivers/vidtv/vidtv_bridge.c:194 vidtv_start_feed drivers/media/test-drivers/vidtv/vidtv_bridge.c:239 dmx_section_feed_start_filtering drivers/media/dvb-core/dvb_demux.c:973 dvb_dmxdev_feed_start drivers/media/dvb-core/dmxdev.c:508 [inline] dvb_dmxdev_feed_restart.isra.0 drivers/media/dvb-core/dmxdev.c:537 dvb_dmxdev_filter_stop+0x2b4/0x3a0 drivers/media/dvb-core/dmxdev.c:564 dvb_dmxdev_filter_free drivers/media/dvb-core/dmxdev.c:840 [inline] dvb_demux_release+0x92/0x550 drivers/media/dvb-core/dmxdev.c:1246 __fput+0x3ff/0xb70 fs/file_tabl ---truncated---

In the Linux kernel, the following vulnerability has been resolved: smb: client: Fix use-after-free in cifs_fill_dirent There is a race condition in the readdir concurrency process, which may access the rsp buffer after it has been released, triggering the following KASAN warning. ================================================================== BUG: KASAN: slab-use-after-free in cifs_fill_dirent+0xb03/0xb60 [cifs] Read of size 4 at addr ffff8880099b819c by task a.out/342975 CPU: 2 UID: 0 PID: 342975 Comm: a.out Not tainted 6.15.0-rc6+ #240 PREEMPT(full) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x53/0x70 print_report+0xce/0x640 kasan_report+0xb8/0xf0 cifs_fill_dirent+0xb03/0xb60 [cifs] cifs_readdir+0x12cb/0x3190 [cifs] iterate_dir+0x1a1/0x520 __x64_sys_getdents+0x134/0x220 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f996f64b9f9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 0d f7 c3 0c 00 f7 d8 64 89 8 RSP: 002b:00007f996f53de78 EFLAGS: 00000207 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f996f53ecdc RCX: 00007f996f64b9f9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f996f53dea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000207 R12: ffffffffffffff88 R13: 0000000000000000 R14: 00007ffc8cd9a500 R15: 00007f996f51e000 </TASK> Allocated by task 408: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 __kasan_slab_alloc+0x6e/0x70 kmem_cache_alloc_noprof+0x117/0x3d0 mempool_alloc_noprof+0xf2/0x2c0 cifs_buf_get+0x36/0x80 [cifs] allocate_buffers+0x1d2/0x330 [cifs] cifs_demultiplex_thread+0x22b/0x2690 [cifs] kthread+0x394/0x720 ret_from_fork+0x34/0x70 ret_from_fork_asm+0x1a/0x30 Freed by task 342979: kasan_save_stack+0x20/0x40 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3b/0x60 __kasan_slab_free+0x37/0x50 kmem_cache_free+0x2b8/0x500 cifs_buf_release+0x3c/0x70 [cifs] cifs_readdir+0x1c97/0x3190 [cifs] iterate_dir+0x1a1/0x520 __x64_sys_getdents64+0x134/0x220 do_syscall_64+0x4b/0x110 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff8880099b8000 which belongs to the cache cifs_request of size 16588 The buggy address is located 412 bytes inside of freed 16588-byte region [ffff8880099b8000, ffff8880099bc0cc) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x99b8 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000 head: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001 head: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000 head: 0080000000000003 ffffea0000266e01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880099b8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880099b8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880099b8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880099b8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880099b8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== POC is available in the link [1]. The problem triggering process is as follows: Process 1 Process 2 ----------------------------------- ---truncated---

In the Linux kernel, the following vulnerability has been resolved: wifi: at76c50x: fix use after free access in at76_disconnect The memory pointed to by priv is freed at the end of at76_delete_device function (using ieee80211_free_hw). But the code then accesses the udev field of the freed object to put the USB device. This may also lead to a memory leak of the usb device. Fix this by using udev from interface.

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: fix use-after-free in ksmbd_session_rpc_open A UAF issue can occur due to a race condition between ksmbd_session_rpc_open() and __session_rpc_close(). Add rpc_lock to the session to protect it.

drivers/infiniband/core/ucma.c in the Linux kernel through 4.17.11 allows ucma_leave_multicast to access a certain data structure after a cleanup step in ucma_process_join, which allows attackers to cause a denial of service (use-after-free).

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: pds_core: remove write-after-free of client_id A use-after-free error popped up in stress testing: [Mon Apr 21 21:21:33 2025] BUG: KFENCE: use-after-free write in pdsc_auxbus_dev_del+0xef/0x160 [pds_core] [Mon Apr 21 21:21:33 2025] Use-after-free write at 0x000000007013ecd1 (in kfence-#47): [Mon Apr 21 21:21:33 2025] pdsc_auxbus_dev_del+0xef/0x160 [pds_core] [Mon Apr 21 21:21:33 2025] pdsc_remove+0xc0/0x1b0 [pds_core] [Mon Apr 21 21:21:33 2025] pci_device_remove+0x24/0x70 [Mon Apr 21 21:21:33 2025] device_release_driver_internal+0x11f/0x180 [Mon Apr 21 21:21:33 2025] driver_detach+0x45/0x80 [Mon Apr 21 21:21:33 2025] bus_remove_driver+0x83/0xe0 [Mon Apr 21 21:21:33 2025] pci_unregister_driver+0x1a/0x80 The actual device uninit usually happens on a separate thread scheduled after this code runs, but there is no guarantee of order of thread execution, so this could be a problem. There's no actual need to clear the client_id at this point, so simply remove the offending code.

In the Linux kernel, the following vulnerability has been resolved: dm: fix dm_blk_report_zones If dm_get_live_table() returned NULL, dm_put_live_table() was never called. Also, it is possible that md->zone_revalidate_map will change while calling this function. Only read it once, so that we are always using the same value. Otherwise we might miss a call to dm_put_live_table(). Finally, while md->zone_revalidate_map is set and a process is calling blk_revalidate_disk_zones() to set up the zone append emulation resources, it is possible that another process, perhaps triggered by blkdev_report_zones_ioctl(), will call dm_blk_report_zones(). If blk_revalidate_disk_zones() fails, these resources can be freed while the other process is still using them, causing a use-after-free error. blk_revalidate_disk_zones() will only ever be called when initially setting up the zone append emulation resources, such as when setting up a zoned dm-crypt table for the first time. Further table swaps will not set md->zone_revalidate_map or call blk_revalidate_disk_zones(). However it must be called using the new table (referenced by md->zone_revalidate_map) and the new queue limits while the DM device is suspended. dm_blk_report_zones() needs some way to distinguish between a call from blk_revalidate_disk_zones(), which must be allowed to use md->zone_revalidate_map to access this not yet activated table, and all other calls to dm_blk_report_zones(), which should not be allowed while the device is suspended and cannot use md->zone_revalidate_map, since the zone resources might be freed by the process currently calling blk_revalidate_disk_zones(). Solve this by tracking the process that sets md->zone_revalidate_map in dm_revalidate_zones() and only allowing that process to make use of it in dm_blk_report_zones().

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: MGMT: Protect mgmt_pending list with its own lock This uses a mutex to protect from concurrent access of mgmt_pending list which can cause crashes like: ================================================================== BUG: KASAN: slab-use-after-free in hci_sock_get_channel+0x60/0x68 net/bluetooth/hci_sock.c:91 Read of size 2 at addr ffff0000c48885b2 by task syz.4.334/7318 CPU: 0 UID: 0 PID: 7318 Comm: syz.4.334 Not tainted 6.15.0-rc7-syzkaller-g187899f4124a #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack+0x30/0x40 lib/dump_stack.c:94 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120 print_address_description+0xa8/0x254 mm/kasan/report.c:408 print_report+0x68/0x84 mm/kasan/report.c:521 kasan_report+0xb0/0x110 mm/kasan/report.c:634 __asan_report_load2_noabort+0x20/0x2c mm/kasan/report_generic.c:379 hci_sock_get_channel+0x60/0x68 net/bluetooth/hci_sock.c:91 mgmt_pending_find+0x7c/0x140 net/bluetooth/mgmt_util.c:223 pending_find net/bluetooth/mgmt.c:947 [inline] remove_adv_monitor+0x44/0x1a4 net/bluetooth/mgmt.c:5445 hci_mgmt_cmd+0x780/0xc00 net/bluetooth/hci_sock.c:1712 hci_sock_sendmsg+0x544/0xbb0 net/bluetooth/hci_sock.c:1832 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg net/socket.c:727 [inline] sock_write_iter+0x25c/0x378 net/socket.c:1131 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x62c/0x97c fs/read_write.c:684 ksys_write+0x120/0x210 fs/read_write.c:736 __do_sys_write fs/read_write.c:747 [inline] __se_sys_write fs/read_write.c:744 [inline] __arm64_sys_write+0x7c/0x90 fs/read_write.c:744 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Allocated by task 7037: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:562 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_noprof+0x2fc/0x4c8 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] sk_prot_alloc+0xc4/0x1f0 net/core/sock.c:2198 sk_alloc+0x44/0x3ac net/core/sock.c:2254 bt_sock_alloc+0x4c/0x300 net/bluetooth/af_bluetooth.c:148 hci_sock_create+0xa8/0x194 net/bluetooth/hci_sock.c:2202 bt_sock_create+0x14c/0x24c net/bluetooth/af_bluetooth.c:132 __sock_create+0x43c/0x91c net/socket.c:1541 sock_create net/socket.c:1599 [inline] __sys_socket_create net/socket.c:1636 [inline] __sys_socket+0xd4/0x1c0 net/socket.c:1683 __do_sys_socket net/socket.c:1697 [inline] __se_sys_socket net/socket.c:1695 [inline] __arm64_sys_socket+0x7c/0x94 net/socket.c:1695 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Freed by task 6607: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x40/0x78 mm/kasan/common.c:68 kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x68/0x88 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline ---truncated---

In the Linux kernel, the following vulnerability has been resolved: btrfs: fix a use-after-free when hitting errors inside btrfs_submit_chunk() [BUG] There is an internal report that KASAN is reporting use-after-free, with the following backtrace: BUG: KASAN: slab-use-after-free in btrfs_check_read_bio+0xa68/0xb70 [btrfs] Read of size 4 at addr ffff8881117cec28 by task kworker/u16:2/45 CPU: 1 UID: 0 PID: 45 Comm: kworker/u16:2 Not tainted 6.11.0-rc2-next-20240805-default+ #76 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 Workqueue: btrfs-endio btrfs_end_bio_work [btrfs] Call Trace: dump_stack_lvl+0x61/0x80 print_address_description.constprop.0+0x5e/0x2f0 print_report+0x118/0x216 kasan_report+0x11d/0x1f0 btrfs_check_read_bio+0xa68/0xb70 [btrfs] process_one_work+0xce0/0x12a0 worker_thread+0x717/0x1250 kthread+0x2e3/0x3c0 ret_from_fork+0x2d/0x70 ret_from_fork_asm+0x11/0x20 Allocated by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 __kasan_slab_alloc+0x7d/0x80 kmem_cache_alloc_noprof+0x16e/0x3e0 mempool_alloc_noprof+0x12e/0x310 bio_alloc_bioset+0x3f0/0x7a0 btrfs_bio_alloc+0x2e/0x50 [btrfs] submit_extent_page+0x4d1/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 Freed by task 20917: kasan_save_stack+0x37/0x60 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x50 __kasan_slab_free+0x4b/0x60 kmem_cache_free+0x214/0x5d0 bio_free+0xed/0x180 end_bbio_data_read+0x1cc/0x580 [btrfs] btrfs_submit_chunk+0x98d/0x1880 [btrfs] btrfs_submit_bio+0x33/0x70 [btrfs] submit_one_bio+0xd4/0x130 [btrfs] submit_extent_page+0x3ea/0xdb0 [btrfs] btrfs_do_readpage+0x8b4/0x12a0 [btrfs] btrfs_readahead+0x29a/0x430 [btrfs] read_pages+0x1a7/0xc60 page_cache_ra_unbounded+0x2ad/0x560 filemap_get_pages+0x629/0xa20 filemap_read+0x335/0xbf0 vfs_read+0x790/0xcb0 ksys_read+0xfd/0x1d0 do_syscall_64+0x6d/0x140 entry_SYSCALL_64_after_hwframe+0x4b/0x53 [CAUSE] Although I cannot reproduce the error, the report itself is good enough to pin down the cause. The call trace is the regular endio workqueue context, but the free-by-task trace is showing that during btrfs_submit_chunk() we already hit a critical error, and is calling btrfs_bio_end_io() to error out. And the original endio function called bio_put() to free the whole bio. This means a double freeing thus causing use-after-free, e.g.: 1. Enter btrfs_submit_bio() with a read bio The read bio length is 128K, crossing two 64K stripes. 2. The first run of btrfs_submit_chunk() 2.1 Call btrfs_map_block(), which returns 64K 2.2 Call btrfs_split_bio() Now there are two bios, one referring to the first 64K, the other referring to the second 64K. 2.3 The first half is submitted. 3. The second run of btrfs_submit_chunk() 3.1 Call btrfs_map_block(), which by somehow failed Now we call btrfs_bio_end_io() to handle the error 3.2 btrfs_bio_end_io() calls the original endio function Which is end_bbio_data_read(), and it calls bio_put() for the original bio. Now the original bio is freed. 4. The submitted first 64K bio finished Now we call into btrfs_check_read_bio() and tries to advance the bio iter. But since the original bio (thus its iter) is already freed, we trigger the above use-after free. And even if the memory is not poisoned/corrupted, we will later call the original endio function, causing a double freeing. [FIX] Instead of calling btrfs_bio_end_io(), call btrfs_orig_bbio_end_io(), which has the extra check on split bios and do the pr ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix use-after-free bugs causing by ptp_ocp_watchdog The ptp_ocp_detach() only shuts down the watchdog timer if it is pending. However, if the timer handler is already running, the timer_delete_sync() is not called. This leads to race conditions where the devlink that contains the ptp_ocp is deallocated while the timer handler is still accessing it, resulting in use-after-free bugs. The following details one of the race scenarios. (thread 1) | (thread 2) ptp_ocp_remove() | ptp_ocp_detach() | ptp_ocp_watchdog() if (timer_pending(&bp->watchdog))| bp = timer_container_of() timer_delete_sync() | | devlink_free(devlink) //free | | bp-> //use Resolve this by unconditionally calling timer_delete_sync() to ensure the timer is reliably deactivated, preventing any access after free.

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Use local fence in error path of xe_migrate_clear The intent of the error path in xe_migrate_clear is to wait on locally generated fence and then return. The code is waiting on m->fence which could be the local fence but this is only stable under the job mutex leading to a possible UAF. Fix code to wait on local fence. (cherry picked from commit 762b7e95362170b3e13a8704f38d5e47eca4ba74)

In the Linux kernel, the following vulnerability has been resolved: ASoC: meson: axg-card: fix 'use-after-free' Buffer 'card->dai_link' is reallocated in 'meson_card_reallocate_links()', so move 'pad' pointer initialization after this function when memory is already reallocated. Kasan bug report: ================================================================== BUG: KASAN: slab-use-after-free in axg_card_add_link+0x76c/0x9bc Read of size 8 at addr ffff000000e8b260 by task modprobe/356 CPU: 0 PID: 356 Comm: modprobe Tainted: G O 6.9.12-sdkernel #1 Call trace: dump_backtrace+0x94/0xec show_stack+0x18/0x24 dump_stack_lvl+0x78/0x90 print_report+0xfc/0x5c0 kasan_report+0xb8/0xfc __asan_load8+0x9c/0xb8 axg_card_add_link+0x76c/0x9bc [snd_soc_meson_axg_sound_card] meson_card_probe+0x344/0x3b8 [snd_soc_meson_card_utils] platform_probe+0x8c/0xf4 really_probe+0x110/0x39c __driver_probe_device+0xb8/0x18c driver_probe_device+0x108/0x1d8 __driver_attach+0xd0/0x25c bus_for_each_dev+0xe0/0x154 driver_attach+0x34/0x44 bus_add_driver+0x134/0x294 driver_register+0xa8/0x1e8 __platform_driver_register+0x44/0x54 axg_card_pdrv_init+0x20/0x1000 [snd_soc_meson_axg_sound_card] do_one_initcall+0xdc/0x25c do_init_module+0x10c/0x334 load_module+0x24c4/0x26cc init_module_from_file+0xd4/0x128 __arm64_sys_finit_module+0x1f4/0x41c invoke_syscall+0x60/0x188 el0_svc_common.constprop.0+0x78/0x13c do_el0_svc+0x30/0x40 el0_svc+0x38/0x78 el0t_64_sync_handler+0x100/0x12c el0t_64_sync+0x190/0x194

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").

In the Linux kernel, the following vulnerability has been resolved: alloc_tag: allocate percpu counters for module tags dynamically When a module gets unloaded it checks whether any of its tags are still in use and if so, we keep the memory containing module's allocation tags alive until all tags are unused. However percpu counters referenced by the tags are freed by free_module(). This will lead to UAF if the memory allocated by a module is accessed after module was unloaded. To fix this we allocate percpu counters for module allocation tags dynamically and we keep it alive for tags which are still in use after module unloading. This also removes the requirement of a larger PERCPU_MODULE_RESERVE when memory allocation profiling is enabled because percpu memory for counters does not need to be reserved anymore.

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.

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: scsi: lpfc: Avoid potential ndlp use-after-free in dev_loss_tmo_callbk Smatch detected a potential use-after-free of an ndlp oject in dev_loss_tmo_callbk during driver unload or fatal error handling. Fix by reordering code to avoid potential use-after-free if initial nodelist reference has been previously removed.

In the Linux kernel, the following vulnerability has been resolved: fscache: delete fscache_cookie_lru_timer when fscache exits to avoid UAF The fscache_cookie_lru_timer is initialized when the fscache module is inserted, but is not deleted when the fscache module is removed. If timer_reduce() is called before removing the fscache module, the fscache_cookie_lru_timer will be added to the timer list of the current cpu. Afterwards, a use-after-free will be triggered in the softIRQ after removing the fscache module, as follows: ================================================================== BUG: unable to handle page fault for address: fffffbfff803c9e9 PF: supervisor read access in kernel mode PF: error_code(0x0000) - not-present page PGD 21ffea067 P4D 21ffea067 PUD 21ffe6067 PMD 110a7c067 PTE 0 Oops: Oops: 0000 [#1] PREEMPT SMP KASAN PTI CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G W 6.11.0-rc3 #855 Tainted: [W]=WARN RIP: 0010:__run_timer_base.part.0+0x254/0x8a0 Call Trace: <IRQ> tmigr_handle_remote_up+0x627/0x810 __walk_groups.isra.0+0x47/0x140 tmigr_handle_remote+0x1fa/0x2f0 handle_softirqs+0x180/0x590 irq_exit_rcu+0x84/0xb0 sysvec_apic_timer_interrupt+0x6e/0x90 </IRQ> <TASK> asm_sysvec_apic_timer_interrupt+0x1a/0x20 RIP: 0010:default_idle+0xf/0x20 default_idle_call+0x38/0x60 do_idle+0x2b5/0x300 cpu_startup_entry+0x54/0x60 start_secondary+0x20d/0x280 common_startup_64+0x13e/0x148 </TASK> Modules linked in: [last unloaded: netfs] ================================================================== Therefore delete fscache_cookie_lru_timer when removing the fscahe module.

In the Linux kernel, the following vulnerability has been resolved: net: atm: add lec_mutex syzbot found its way in net/atm/lec.c, and found an error path in lecd_attach() could leave a dangling pointer in dev_lec[]. Add a mutex to protect dev_lecp[] uses from lecd_attach(), lec_vcc_attach() and lec_mcast_attach(). Following patch will use this mutex for /proc/net/atm/lec. BUG: KASAN: slab-use-after-free in lecd_attach net/atm/lec.c:751 [inline] BUG: KASAN: slab-use-after-free in lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008 Read of size 8 at addr ffff88807c7b8e68 by task syz.1.17/6142 CPU: 1 UID: 0 PID: 6142 Comm: syz.1.17 Not tainted 6.16.0-rc1-syzkaller-00239-g08215f5486ec #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xcd/0x680 mm/kasan/report.c:521 kasan_report+0xe0/0x110 mm/kasan/report.c:634 lecd_attach net/atm/lec.c:751 [inline] lane_ioctl+0x2224/0x23e0 net/atm/lec.c:1008 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x118/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f </TASK> Allocated by task 6132: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4328 [inline] __kvmalloc_node_noprof+0x27b/0x620 mm/slub.c:5015 alloc_netdev_mqs+0xd2/0x1570 net/core/dev.c:11711 lecd_attach net/atm/lec.c:737 [inline] lane_ioctl+0x17db/0x23e0 net/atm/lec.c:1008 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x118/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6132: kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x51/0x70 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2381 [inline] slab_free mm/slub.c:4643 [inline] kfree+0x2b4/0x4d0 mm/slub.c:4842 free_netdev+0x6c5/0x910 net/core/dev.c:11892 lecd_attach net/atm/lec.c:744 [inline] lane_ioctl+0x1ce8/0x23e0 net/atm/lec.c:1008 do_vcc_ioctl+0x12c/0x930 net/atm/ioctl.c:159 sock_do_ioctl+0x118/0x280 net/socket.c:1190 sock_ioctl+0x227/0x6b0 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18e/0x210 fs/ioctl.c:893

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: 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: HID: appletb-kbd: fix slab use-after-free bug in appletb_kbd_probe In probe appletb_kbd_probe() a "struct appletb_kbd *kbd" is allocated via devm_kzalloc() to store touch bar keyboard related data. Later on if backlight_device_get_by_name() finds a backlight device with name "appletb_backlight" a timer (kbd->inactivity_timer) is setup with appletb_inactivity_timer() and the timer is armed to run after appletb_tb_dim_timeout (60) seconds. A use-after-free is triggered when failure occurs after the timer is armed. This ultimately means probe failure occurs and as a result the "struct appletb_kbd *kbd" which is device managed memory is freed. After 60 seconds the timer will have expired and __run_timers will attempt to access the timer (kbd->inactivity_timer) however the kdb structure has been freed causing a use-after free. [ 71.636938] ================================================================== [ 71.637915] BUG: KASAN: slab-use-after-free in __run_timers+0x7ad/0x890 [ 71.637915] Write of size 8 at addr ffff8881178c5958 by task swapper/1/0 [ 71.637915] [ 71.637915] CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Not tainted 6.16.0-rc2-00318-g739a6c93cc75-dirty #12 PREEMPT(voluntary) [ 71.637915] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 [ 71.637915] Call Trace: [ 71.637915] <IRQ> [ 71.637915] dump_stack_lvl+0x53/0x70 [ 71.637915] print_report+0xce/0x670 [ 71.637915] ? __run_timers+0x7ad/0x890 [ 71.637915] kasan_report+0xce/0x100 [ 71.637915] ? __run_timers+0x7ad/0x890 [ 71.637915] __run_timers+0x7ad/0x890 [ 71.637915] ? __pfx___run_timers+0x10/0x10 [ 71.637915] ? update_process_times+0xfc/0x190 [ 71.637915] ? __pfx_update_process_times+0x10/0x10 [ 71.637915] ? _raw_spin_lock_irq+0x80/0xe0 [ 71.637915] ? _raw_spin_lock_irq+0x80/0xe0 [ 71.637915] ? __pfx__raw_spin_lock_irq+0x10/0x10 [ 71.637915] run_timer_softirq+0x141/0x240 [ 71.637915] ? __pfx_run_timer_softirq+0x10/0x10 [ 71.637915] ? __pfx___hrtimer_run_queues+0x10/0x10 [ 71.637915] ? kvm_clock_get_cycles+0x18/0x30 [ 71.637915] ? ktime_get+0x60/0x140 [ 71.637915] handle_softirqs+0x1b8/0x5c0 [ 71.637915] ? __pfx_handle_softirqs+0x10/0x10 [ 71.637915] irq_exit_rcu+0xaf/0xe0 [ 71.637915] sysvec_apic_timer_interrupt+0x6c/0x80 [ 71.637915] </IRQ> [ 71.637915] [ 71.637915] Allocated by task 39: [ 71.637915] kasan_save_stack+0x33/0x60 [ 71.637915] kasan_save_track+0x14/0x30 [ 71.637915] __kasan_kmalloc+0x8f/0xa0 [ 71.637915] __kmalloc_node_track_caller_noprof+0x195/0x420 [ 71.637915] devm_kmalloc+0x74/0x1e0 [ 71.637915] appletb_kbd_probe+0x37/0x3c0 [ 71.637915] hid_device_probe+0x2d1/0x680 [ 71.637915] really_probe+0x1c3/0x690 [ 71.637915] __driver_probe_device+0x247/0x300 [ 71.637915] driver_probe_device+0x49/0x210 [...] [ 71.637915] [ 71.637915] Freed by task 39: [ 71.637915] kasan_save_stack+0x33/0x60 [ 71.637915] kasan_save_track+0x14/0x30 [ 71.637915] kasan_save_free_info+0x3b/0x60 [ 71.637915] __kasan_slab_free+0x37/0x50 [ 71.637915] kfree+0xcf/0x360 [ 71.637915] devres_release_group+0x1f8/0x3c0 [ 71.637915] hid_device_probe+0x315/0x680 [ 71.637915] really_probe+0x1c3/0x690 [ 71.637915] __driver_probe_device+0x247/0x300 [ 71.637915] driver_probe_device+0x49/0x210 [...] The root cause of the issue is that the timer is not disarmed on failure paths leading to it remaining active and accessing freed memory. To fix this call timer_delete_sync() to deactivate the timer. Another small issue is that timer_delete_sync is called unconditionally in appletb_kbd_remove(), fix this by checking for a valid kbd->backlight_dev before calling timer_delete_sync.

In the Linux kernel, the following vulnerability has been resolved: drm/gem: Acquire references on GEM handles for framebuffers A GEM handle can be released while the GEM buffer object is attached to a DRM framebuffer. This leads to the release of the dma-buf backing the buffer object, if any. [1] Trying to use the framebuffer in further mode-setting operations leads to a segmentation fault. Most easily happens with driver that use shadow planes for vmap-ing the dma-buf during a page flip. An example is shown below. [ 156.791968] ------------[ cut here ]------------ [ 156.796830] WARNING: CPU: 2 PID: 2255 at drivers/dma-buf/dma-buf.c:1527 dma_buf_vmap+0x224/0x430 [...] [ 156.942028] RIP: 0010:dma_buf_vmap+0x224/0x430 [ 157.043420] Call Trace: [ 157.045898] <TASK> [ 157.048030] ? show_trace_log_lvl+0x1af/0x2c0 [ 157.052436] ? show_trace_log_lvl+0x1af/0x2c0 [ 157.056836] ? show_trace_log_lvl+0x1af/0x2c0 [ 157.061253] ? drm_gem_shmem_vmap+0x74/0x710 [ 157.065567] ? dma_buf_vmap+0x224/0x430 [ 157.069446] ? __warn.cold+0x58/0xe4 [ 157.073061] ? dma_buf_vmap+0x224/0x430 [ 157.077111] ? report_bug+0x1dd/0x390 [ 157.080842] ? handle_bug+0x5e/0xa0 [ 157.084389] ? exc_invalid_op+0x14/0x50 [ 157.088291] ? asm_exc_invalid_op+0x16/0x20 [ 157.092548] ? dma_buf_vmap+0x224/0x430 [ 157.096663] ? dma_resv_get_singleton+0x6d/0x230 [ 157.101341] ? __pfx_dma_buf_vmap+0x10/0x10 [ 157.105588] ? __pfx_dma_resv_get_singleton+0x10/0x10 [ 157.110697] drm_gem_shmem_vmap+0x74/0x710 [ 157.114866] drm_gem_vmap+0xa9/0x1b0 [ 157.118763] drm_gem_vmap_unlocked+0x46/0xa0 [ 157.123086] drm_gem_fb_vmap+0xab/0x300 [ 157.126979] drm_atomic_helper_prepare_planes.part.0+0x487/0xb10 [ 157.133032] ? lockdep_init_map_type+0x19d/0x880 [ 157.137701] drm_atomic_helper_commit+0x13d/0x2e0 [ 157.142671] ? drm_atomic_nonblocking_commit+0xa0/0x180 [ 157.147988] drm_mode_atomic_ioctl+0x766/0xe40 [...] [ 157.346424] ---[ end trace 0000000000000000 ]--- Acquiring GEM handles for the framebuffer's GEM buffer objects prevents this from happening. The framebuffer's cleanup later puts the handle references. Commit 1a148af06000 ("drm/gem-shmem: Use dma_buf from GEM object instance") triggers the segmentation fault easily by using the dma-buf field more widely. The underlying issue with reference counting has been present before. v2: - acquire the handle instead of the BO (Christian) - fix comment style (Christian) - drop the Fixes tag (Christian) - rename err_ gotos - add missing Link tag

In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: remove tag set when second admin queue config fails Commit 104d0e2f6222 ("nvme-fabrics: reset admin connection for secure concatenation") modified nvme_tcp_setup_ctrl() to call nvme_tcp_configure_admin_queue() twice. The first call prepares for DH-CHAP negotitation, and the second call is required for secure concatenation. However, this change triggered BUG KASAN slab-use-after- free in blk_mq_queue_tag_busy_iter(). This BUG can be recreated by repeating the blktests test case nvme/063 a few times [1]. When the BUG happens, nvme_tcp_create_ctrl() fails in the call chain below: nvme_tcp_create_ctrl() nvme_tcp_alloc_ctrl() new=true ... Alloc nvme_tcp_ctrl and admin_tag_set nvme_tcp_setup_ctrl() new=true nvme_tcp_configure_admin_queue() new=true ... Succeed nvme_alloc_admin_tag_set() ... Alloc the tag set for admin_tag_set nvme_stop_keep_alive() nvme_tcp_teardown_admin_queue() remove=false nvme_tcp_configure_admin_queue() new=false nvme_tcp_alloc_admin_queue() ... Fail, but do not call nvme_remove_admin_tag_set() nvme_uninit_ctrl() nvme_put_ctrl() ... Free up the nvme_tcp_ctrl and admin_tag_set The first call of nvme_tcp_configure_admin_queue() succeeds with new=true argument. The second call fails with new=false argument. This second call does not call nvme_remove_admin_tag_set() on failure, due to the new=false argument. Then the admin tag set is not removed. However, nvme_tcp_create_ctrl() assumes that nvme_tcp_setup_ctrl() would call nvme_remove_admin_tag_set(). Then it frees up struct nvme_tcp_ctrl which has admin_tag_set field. Later on, the timeout handler accesses the admin_tag_set field and causes the BUG KASAN slab-use-after-free. To not leave the admin tag set, call nvme_remove_admin_tag_set() when the second nvme_tcp_configure_admin_queue() call fails. Do not return from nvme_tcp_setup_ctrl() on failure. Instead, jump to "destroy_admin" go-to label to call nvme_tcp_teardown_admin_queue() which calls nvme_remove_admin_tag_set().

In the Linux kernel, the following vulnerability has been resolved: RDMA/iwcm: Fix use-after-free of work objects after cm_id destruction The commit 59c68ac31e15 ("iw_cm: free cm_id resources on the last deref") simplified cm_id resource management by freeing cm_id once all references to the cm_id were removed. The references are removed either upon completion of iw_cm event handlers or when the application destroys the cm_id. This commit introduced the use-after-free condition where cm_id_private object could still be in use by event handler works during the destruction of cm_id. The commit aee2424246f9 ("RDMA/iwcm: Fix a use-after-free related to destroying CM IDs") addressed this use-after- free by flushing all pending works at the cm_id destruction. However, still another use-after-free possibility remained. It happens with the work objects allocated for each cm_id_priv within alloc_work_entries() during cm_id creation, and subsequently freed in dealloc_work_entries() once all references to the cm_id are removed. If the cm_id's last reference is decremented in the event handler work, the work object for the work itself gets removed, and causes the use- after-free BUG below: BUG: KASAN: slab-use-after-free in __pwq_activate_work+0x1ff/0x250 Read of size 8 at addr ffff88811f9cf800 by task kworker/u16:1/147091 CPU: 2 UID: 0 PID: 147091 Comm: kworker/u16:1 Not tainted 6.15.0-rc2+ #27 PREEMPT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 Workqueue: 0x0 (iw_cm_wq) Call Trace: <TASK> dump_stack_lvl+0x6a/0x90 print_report+0x174/0x554 ? __virt_addr_valid+0x208/0x430 ? __pwq_activate_work+0x1ff/0x250 kasan_report+0xae/0x170 ? __pwq_activate_work+0x1ff/0x250 __pwq_activate_work+0x1ff/0x250 pwq_dec_nr_in_flight+0x8c5/0xfb0 process_one_work+0xc11/0x1460 ? __pfx_process_one_work+0x10/0x10 ? assign_work+0x16c/0x240 worker_thread+0x5ef/0xfd0 ? __pfx_worker_thread+0x10/0x10 kthread+0x3b0/0x770 ? __pfx_kthread+0x10/0x10 ? rcu_is_watching+0x11/0xb0 ? _raw_spin_unlock_irq+0x24/0x50 ? rcu_is_watching+0x11/0xb0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x30/0x70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> Allocated by task 147416: kasan_save_stack+0x2c/0x50 kasan_save_track+0x10/0x30 __kasan_kmalloc+0xa6/0xb0 alloc_work_entries+0xa9/0x260 [iw_cm] iw_cm_connect+0x23/0x4a0 [iw_cm] rdma_connect_locked+0xbfd/0x1920 [rdma_cm] nvme_rdma_cm_handler+0x8e5/0x1b60 [nvme_rdma] cma_cm_event_handler+0xae/0x320 [rdma_cm] cma_work_handler+0x106/0x1b0 [rdma_cm] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 Freed by task 147091: kasan_save_stack+0x2c/0x50 kasan_save_track+0x10/0x30 kasan_save_free_info+0x37/0x60 __kasan_slab_free+0x4b/0x70 kfree+0x13a/0x4b0 dealloc_work_entries+0x125/0x1f0 [iw_cm] iwcm_deref_id+0x6f/0xa0 [iw_cm] cm_work_handler+0x136/0x1ba0 [iw_cm] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 Last potentially related work creation: kasan_save_stack+0x2c/0x50 kasan_record_aux_stack+0xa3/0xb0 __queue_work+0x2ff/0x1390 queue_work_on+0x67/0xc0 cm_event_handler+0x46a/0x820 [iw_cm] siw_cm_upcall+0x330/0x650 [siw] siw_cm_work_handler+0x6b9/0x2b20 [siw] process_one_work+0x84f/0x1460 worker_thread+0x5ef/0xfd0 kthread+0x3b0/0x770 ret_from_fork+0x30/0x70 ret_from_fork_asm+0x1a/0x30 This BUG is reproducible by repeating the blktests test case nvme/061 for the rdma transport and the siw driver. To avoid the use-after-free of cm_id_private work objects, ensure that the last reference to the cm_id is decremented not in the event handler works, but in the cm_id destruction context. For that purpose, mo ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ksmbd: Fix UAF in __close_file_table_ids A use-after-free is possible if one thread destroys the file via __ksmbd_close_fd while another thread holds a reference to it. The existing checks on fp->refcount are not sufficient to prevent this. The fix takes ft->lock around the section which removes the file from the file table. This prevents two threads acquiring the same file pointer via __close_file_table_ids, as well as the other functions which retrieve a file from the IDR and which already use this same lock.

In the Linux kernel, the following vulnerability has been resolved: smb: client: fix use-after-free in crypt_message when using async crypto The CVE-2024-50047 fix removed asynchronous crypto handling from crypt_message(), assuming all crypto operations are synchronous. However, when hardware crypto accelerators are used, this can cause use-after-free crashes: crypt_message() // Allocate the creq buffer containing the req creq = smb2_get_aead_req(..., &req); // Async encryption returns -EINPROGRESS immediately rc = enc ? crypto_aead_encrypt(req) : crypto_aead_decrypt(req); // Free creq while async operation is still in progress kvfree_sensitive(creq, ...); Hardware crypto modules often implement async AEAD operations for performance. When crypto_aead_encrypt/decrypt() returns -EINPROGRESS, the operation completes asynchronously. Without crypto_wait_req(), the function immediately frees the request buffer, leading to crashes when the driver later accesses the freed memory. This results in a use-after-free condition when the hardware crypto driver later accesses the freed request structure, leading to kernel crashes with NULL pointer dereferences. The issue occurs because crypto_alloc_aead() with mask=0 doesn't guarantee synchronous operation. Even without CRYPTO_ALG_ASYNC in the mask, async implementations can be selected. Fix by restoring the async crypto handling: - DECLARE_CRYPTO_WAIT(wait) for completion tracking - aead_request_set_callback() for async completion notification - crypto_wait_req() to wait for operation completion This ensures the request buffer isn't freed until the crypto operation completes, whether synchronous or asynchronous, while preserving the CVE-2024-50047 fix.