In the Linux kernel, the following vulnerability has been resolved: tracing/timerlat: Only clear timer if a kthread exists The timerlat tracer can use user space threads to check for osnoise and timer latency. If the program using this is killed via a SIGTERM, the threads are shutdown one at a time and another tracing instance can start up resetting the threads before they are fully closed. That causes the hrtimer assigned to the kthread to be shutdown and freed twice when the dying thread finally closes the file descriptors, causing a use-after-free bug. Only cancel the hrtimer if the associated thread is still around. Also add the interface_lock around the resetting of the tlat_var->kthread. Note, this is just a quick fix that can be backported to stable. A real fix is to have a better synchronization between the shutdown of old threads and the starting of new ones.

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to avoid use-after-free in f2fs_stop_gc_thread() syzbot reports a f2fs bug as below: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_report+0xe8/0x550 mm/kasan/report.c:491 kasan_report+0x143/0x180 mm/kasan/report.c:601 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline] __refcount_add include/linux/refcount.h:184 [inline] __refcount_inc include/linux/refcount.h:241 [inline] refcount_inc include/linux/refcount.h:258 [inline] get_task_struct include/linux/sched/task.h:118 [inline] kthread_stop+0xca/0x630 kernel/kthread.c:704 f2fs_stop_gc_thread+0x65/0xb0 fs/f2fs/gc.c:210 f2fs_do_shutdown+0x192/0x540 fs/f2fs/file.c:2283 f2fs_ioc_shutdown fs/f2fs/file.c:2325 [inline] __f2fs_ioctl+0x443a/0xbe60 fs/f2fs/file.c:4325 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The root cause is below race condition, it may cause use-after-free issue in sbi->gc_th pointer. - remount - f2fs_remount - f2fs_stop_gc_thread - kfree(gc_th) - f2fs_ioc_shutdown - f2fs_do_shutdown - f2fs_stop_gc_thread - kthread_stop(gc_th->f2fs_gc_task) : sbi->gc_thread = NULL; We will call f2fs_do_shutdown() in two paths: - for f2fs_ioc_shutdown() path, we should grab sb->s_umount semaphore for fixing. - for f2fs_shutdown() path, it's safe since caller has already grabbed sb->s_umount semaphore.

In the Linux kernel, the following vulnerability has been resolved: scsi: libsas: Fix use-after-free bug in smp_execute_task_sg() When executing SMP task failed, the smp_execute_task_sg() calls del_timer() to delete "slow_task->timer". However, if the timer handler sas_task_internal_timedout() is running, the del_timer() in smp_execute_task_sg() will not stop it and a UAF will happen. The process is shown below: (thread 1) | (thread 2) smp_execute_task_sg() | sas_task_internal_timedout() ... | del_timer() | ... | ... sas_free_task(task) | kfree(task->slow_task) //FREE| | task->slow_task->... //USE Fix by calling del_timer_sync() in smp_execute_task_sg(), which makes sure the timer handler have finished before the "task->slow_task" is deallocated.

In the Linux kernel, the following vulnerability has been resolved: kernfs: fix use-after-free in __kernfs_remove Syzkaller managed to trigger concurrent calls to kernfs_remove_by_name_ns() for the same file resulting in a KASAN detected use-after-free. The race occurs when the root node is freed during kernfs_drain(). To prevent this acquire an additional reference for the root of the tree that is removed before calling __kernfs_remove(). Found by syzkaller with the following reproducer (slab_nomerge is required): syz_mount_image$ext4(0x0, &(0x7f0000000100)='./file0\x00', 0x100000, 0x0, 0x0, 0x0, 0x0) r0 = openat(0xffffffffffffff9c, &(0x7f0000000080)='/proc/self/exe\x00', 0x0, 0x0) close(r0) pipe2(&(0x7f0000000140)={0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x800) mount$9p_fd(0x0, &(0x7f0000000040)='./file0\x00', &(0x7f00000000c0), 0x408, &(0x7f0000000280)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@cache_loose}, {@mmap}, {@loose}, {@loose}, {@mmap}], [{@mask={'mask', 0x3d, '^MAY_EXEC'}}, {@fsmagic={'fsmagic', 0x3d, 0x10001}}, {@dont_hash}]}}) Sample report: ================================================================== BUG: KASAN: use-after-free in kernfs_type include/linux/kernfs.h:335 [inline] BUG: KASAN: use-after-free in kernfs_leftmost_descendant fs/kernfs/dir.c:1261 [inline] BUG: KASAN: use-after-free in __kernfs_remove.part.0+0x843/0x960 fs/kernfs/dir.c:1369 Read of size 2 at addr ffff8880088807f0 by task syz-executor.2/857 CPU: 0 PID: 857 Comm: syz-executor.2 Not tainted 6.0.0-rc3-00363-g7726d4c3e60b #5 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x6e/0x91 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold+0x5e/0x5e5 mm/kasan/report.c:433 kasan_report+0xa3/0x130 mm/kasan/report.c:495 kernfs_type include/linux/kernfs.h:335 [inline] kernfs_leftmost_descendant fs/kernfs/dir.c:1261 [inline] __kernfs_remove.part.0+0x843/0x960 fs/kernfs/dir.c:1369 __kernfs_remove fs/kernfs/dir.c:1356 [inline] kernfs_remove_by_name_ns+0x108/0x190 fs/kernfs/dir.c:1589 sysfs_slab_add+0x133/0x1e0 mm/slub.c:5943 __kmem_cache_create+0x3e0/0x550 mm/slub.c:4899 create_cache mm/slab_common.c:229 [inline] kmem_cache_create_usercopy+0x167/0x2a0 mm/slab_common.c:335 p9_client_create+0xd4d/0x1190 net/9p/client.c:993 v9fs_session_init+0x1e6/0x13c0 fs/9p/v9fs.c:408 v9fs_mount+0xb9/0xbd0 fs/9p/vfs_super.c:126 legacy_get_tree+0xf1/0x200 fs/fs_context.c:610 vfs_get_tree+0x85/0x2e0 fs/super.c:1530 do_new_mount fs/namespace.c:3040 [inline] path_mount+0x675/0x1d00 fs/namespace.c:3370 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] __se_sys_mount fs/namespace.c:3568 [inline] __x64_sys_mount+0x282/0x300 fs/namespace.c:3568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f725f983aed Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f725f0f7028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f725faa3f80 RCX: 00007f725f983aed RDX: 00000000200000c0 RSI: 0000000020000040 RDI: 0000000000000000 RBP: 00007f725f9f419c R08: 0000000020000280 R09: 0000000000000000 R10: 0000000000000408 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000006 R14: 00007f725faa3f80 R15: 00007f725f0d7000 </TASK> Allocated by task 855: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:470 kasan_slab_alloc include/linux/kasan.h:224 [inline] slab_post_alloc_hook mm/slab.h:7 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: sch/netem: fix use after free in netem_dequeue If netem_dequeue() enqueues packet to inner qdisc and that qdisc returns __NET_XMIT_STOLEN. The packet is dropped but qdisc_tree_reduce_backlog() is not called to update the parent's q.qlen, leading to the similar use-after-free as Commit e04991a48dbaf382 ("netem: fix return value if duplicate enqueue fails") Commands to trigger KASAN UaF: ip link add type dummy ip link set lo up ip link set dummy0 up tc qdisc add dev lo parent root handle 1: drr tc filter add dev lo parent 1: basic classid 1:1 tc class add dev lo classid 1:1 drr tc qdisc add dev lo parent 1:1 handle 2: netem tc qdisc add dev lo parent 2: handle 3: drr tc filter add dev lo parent 3: basic classid 3:1 action mirred egress redirect dev dummy0 tc class add dev lo classid 3:1 drr ping -c1 -W0.01 localhost # Trigger bug tc class del dev lo classid 1:1 tc class add dev lo classid 1:1 drr ping -c1 -W0.01 localhost # UaF

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: VMCI: Fix use-after-free when removing resource in vmci_resource_remove() When removing a resource from vmci_resource_table in vmci_resource_remove(), the search is performed using the resource handle by comparing context and resource fields. It is possible though to create two resources with different types but same handle (same context and resource fields). When trying to remove one of the resources, vmci_resource_remove() may not remove the intended one, but the object will still be freed as in the case of the datagram type in vmci_datagram_destroy_handle(). vmci_resource_table will still hold a pointer to this freed resource leading to a use-after-free vulnerability. BUG: KASAN: use-after-free in vmci_handle_is_equal include/linux/vmw_vmci_defs.h:142 [inline] BUG: KASAN: use-after-free in vmci_resource_remove+0x3a1/0x410 drivers/misc/vmw_vmci/vmci_resource.c:147 Read of size 4 at addr ffff88801c16d800 by task syz-executor197/1592 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x82/0xa9 lib/dump_stack.c:106 print_address_description.constprop.0+0x21/0x366 mm/kasan/report.c:239 __kasan_report.cold+0x7f/0x132 mm/kasan/report.c:425 kasan_report+0x38/0x51 mm/kasan/report.c:442 vmci_handle_is_equal include/linux/vmw_vmci_defs.h:142 [inline] vmci_resource_remove+0x3a1/0x410 drivers/misc/vmw_vmci/vmci_resource.c:147 vmci_qp_broker_detach+0x89a/0x11b9 drivers/misc/vmw_vmci/vmci_queue_pair.c:2182 ctx_free_ctx+0x473/0xbe1 drivers/misc/vmw_vmci/vmci_context.c:444 kref_put include/linux/kref.h:65 [inline] vmci_ctx_put drivers/misc/vmw_vmci/vmci_context.c:497 [inline] vmci_ctx_destroy+0x170/0x1d6 drivers/misc/vmw_vmci/vmci_context.c:195 vmci_host_close+0x125/0x1ac drivers/misc/vmw_vmci/vmci_host.c:143 __fput+0x261/0xa34 fs/file_table.c:282 task_work_run+0xf0/0x194 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x184/0x189 kernel/entry/common.c:187 exit_to_user_mode_prepare+0x11b/0x123 kernel/entry/common.c:220 __syscall_exit_to_user_mode_work kernel/entry/common.c:302 [inline] syscall_exit_to_user_mode+0x18/0x42 kernel/entry/common.c:313 do_syscall_64+0x41/0x85 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x6e/0x0 This change ensures the type is also checked when removing the resource from vmci_resource_table in vmci_resource_remove().

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix potential UAF in nfsd4_cb_getattr_release Once we drop the delegation reference, the fields embedded in it are no longer safe to access. Do that last.

In the Linux kernel, the following vulnerability has been resolved: usb: dwc3: st: fix probed platform device ref count on probe error path The probe function never performs any paltform device allocation, thus error path "undo_platform_dev_alloc" is entirely bogus. It drops the reference count from the platform device being probed. If error path is triggered, this will lead to unbalanced device reference counts and premature release of device resources, thus possible use-after-free when releasing remaining devm-managed resources.

In the Linux kernel, the following vulnerability has been resolved: powerpc/mm/fault: Fix kfence page fault reporting copy_from_kernel_nofault() can be called when doing read of /proc/kcore. /proc/kcore can have some unmapped kfence objects which when read via copy_from_kernel_nofault() can cause page faults. Since *_nofault() functions define their own fixup table for handling fault, use that instead of asking kfence to handle such faults. Hence we search the exception tables for the nip which generated the fault. If there is an entry then we let the fixup table handler handle the page fault by returning an error from within ___do_page_fault(). This can be easily triggered if someone tries to do dd from /proc/kcore. eg. dd if=/proc/kcore of=/dev/null bs=1M Some example false negatives: =============================== BUG: KFENCE: invalid read in copy_from_kernel_nofault+0x9c/0x1a0 Invalid read at 0xc0000000fdff0000: copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec BUG: KFENCE: use-after-free read in copy_from_kernel_nofault+0x9c/0x1a0 Use-after-free read at 0xc0000000fe050000 (in kfence-#2): copy_from_kernel_nofault+0x9c/0x1a0 0xc00000000665f950 read_kcore_iter+0x57c/0xa04 proc_reg_read_iter+0xe4/0x16c vfs_read+0x320/0x3ec ksys_read+0x90/0x154 system_call_exception+0x120/0x310 system_call_vectored_common+0x15c/0x2ec

In the Linux kernel, the following vulnerability has been resolved: drm/xe: prevent UAF around preempt fence The fence lock is part of the queue, therefore in the current design anything locking the fence should then also hold a ref to the queue to prevent the queue from being freed. However, currently it looks like we signal the fence and then drop the queue ref, but if something is waiting on the fence, the waiter is kicked to wake up at some later point, where upon waking up it first grabs the lock before checking the fence state. But if we have already dropped the queue ref, then the lock might already be freed as part of the queue, leading to uaf. To prevent this, move the fence lock into the fence itself so we don't run into lifetime issues. Alternative might be to have device level lock, or only release the queue in the fence release callback, however that might require pushing to another worker to avoid locking issues. References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2454 References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2342 References: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/2020 (cherry picked from commit 7116c35aacedc38be6d15bd21b2fc936eed0008b)

In the Linux kernel, the following vulnerability has been resolved: drm/meson: reorder driver deinit sequence to fix use-after-free bug Unloading the driver triggers the following KASAN warning: [ +0.006275] ============================================================= [ +0.000029] BUG: KASAN: use-after-free in __list_del_entry_valid+0xe0/0x1a0 [ +0.000026] Read of size 8 at addr ffff000020c395e0 by task rmmod/2695 [ +0.000019] CPU: 5 PID: 2695 Comm: rmmod Tainted: G C O 5.19.0-rc6-lrmbkasan+ #1 [ +0.000013] Hardware name: Hardkernel ODROID-N2Plus (DT) [ +0.000008] Call trace: [ +0.000007] dump_backtrace+0x1ec/0x280 [ +0.000013] show_stack+0x24/0x80 [ +0.000008] dump_stack_lvl+0x98/0xd4 [ +0.000011] print_address_description.constprop.0+0x80/0x520 [ +0.000011] print_report+0x128/0x260 [ +0.000007] kasan_report+0xb8/0xfc [ +0.000008] __asan_report_load8_noabort+0x3c/0x50 [ +0.000010] __list_del_entry_valid+0xe0/0x1a0 [ +0.000009] drm_atomic_private_obj_fini+0x30/0x200 [drm] [ +0.000172] drm_bridge_detach+0x94/0x260 [drm] [ +0.000145] drm_encoder_cleanup+0xa4/0x290 [drm] [ +0.000144] drm_mode_config_cleanup+0x118/0x740 [drm] [ +0.000143] drm_mode_config_init_release+0x1c/0x2c [drm] [ +0.000144] drm_managed_release+0x170/0x414 [drm] [ +0.000142] drm_dev_put.part.0+0xc0/0x124 [drm] [ +0.000143] drm_dev_put+0x20/0x30 [drm] [ +0.000142] meson_drv_unbind+0x1d8/0x2ac [meson_drm] [ +0.000028] take_down_aggregate_device+0xb0/0x160 [ +0.000016] component_del+0x18c/0x360 [ +0.000009] meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi] [ +0.000015] platform_remove+0x64/0xb0 [ +0.000009] device_remove+0xb8/0x154 [ +0.000009] device_release_driver_internal+0x398/0x5b0 [ +0.000009] driver_detach+0xac/0x1b0 [ +0.000009] bus_remove_driver+0x158/0x29c [ +0.000009] driver_unregister+0x70/0xb0 [ +0.000008] platform_driver_unregister+0x20/0x2c [ +0.000008] meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi] [ +0.000012] __do_sys_delete_module+0x288/0x400 [ +0.000011] __arm64_sys_delete_module+0x5c/0x80 [ +0.000009] invoke_syscall+0x74/0x260 [ +0.000009] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000009] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000012] el0t_64_sync_handler+0x11c/0x150 [ +0.000008] el0t_64_sync+0x18c/0x190 [ +0.000018] Allocated by task 0: [ +0.000007] (stack is not available) [ +0.000011] Freed by task 2695: [ +0.000008] kasan_save_stack+0x2c/0x5c [ +0.000011] kasan_set_track+0x2c/0x40 [ +0.000008] kasan_set_free_info+0x28/0x50 [ +0.000009] ____kasan_slab_free+0x128/0x1d4 [ +0.000008] __kasan_slab_free+0x18/0x24 [ +0.000007] slab_free_freelist_hook+0x108/0x230 [ +0.000011] kfree+0x110/0x35c [ +0.000008] release_nodes+0xf0/0x16c [ +0.000009] devres_release_group+0x180/0x270 [ +0.000008] component_unbind+0x128/0x1e0 [ +0.000010] component_unbind_all+0x1b8/0x264 [ +0.000009] meson_drv_unbind+0x1a0/0x2ac [meson_drm] [ +0.000025] take_down_aggregate_device+0xb0/0x160 [ +0.000009] component_del+0x18c/0x360 [ +0.000009] meson_dw_hdmi_remove+0x28/0x40 [meson_dw_hdmi] [ +0.000012] platform_remove+0x64/0xb0 [ +0.000008] device_remove+0xb8/0x154 [ +0.000009] device_release_driver_internal+0x398/0x5b0 [ +0.000009] driver_detach+0xac/0x1b0 [ +0.000009] bus_remove_driver+0x158/0x29c [ +0.000008] driver_unregister+0x70/0xb0 [ +0.000008] platform_driver_unregister+0x20/0x2c [ +0.000008] meson_dw_hdmi_platform_driver_exit+0x1c/0x30 [meson_dw_hdmi] [ +0.000011] __do_sys_delete_module+0x288/0x400 [ +0.000010] __arm64_sys_delete_module+0x5c/0x80 [ +0.000008] invoke_syscall+0x74/0x260 [ +0.000008] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000009] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64_sync+0x18c/0x190 [ +0.000014] The buggy address belongs to the object at ffff000020c39000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ext4: avoid OOB when system.data xattr changes underneath the filesystem When looking up for an entry in an inlined directory, if e_value_offs is changed underneath the filesystem by some change in the block device, it will lead to an out-of-bounds access that KASAN detects as an UAF. EXT4-fs (loop0): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. loop0: detected capacity change from 2048 to 2047 ================================================================== BUG: KASAN: use-after-free in ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500 Read of size 1 at addr ffff88803e91130f by task syz-executor269/5103 CPU: 0 UID: 0 PID: 5103 Comm: syz-executor269 Not tainted 6.11.0-rc4-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500 ext4_find_inline_entry+0x4be/0x5e0 fs/ext4/inline.c:1697 __ext4_find_entry+0x2b4/0x1b30 fs/ext4/namei.c:1573 ext4_lookup_entry fs/ext4/namei.c:1727 [inline] ext4_lookup+0x15f/0x750 fs/ext4/namei.c:1795 lookup_one_qstr_excl+0x11f/0x260 fs/namei.c:1633 filename_create+0x297/0x540 fs/namei.c:3980 do_symlinkat+0xf9/0x3a0 fs/namei.c:4587 __do_sys_symlinkat fs/namei.c:4610 [inline] __se_sys_symlinkat fs/namei.c:4607 [inline] __x64_sys_symlinkat+0x95/0xb0 fs/namei.c:4607 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3e73ced469 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 21 18 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff4d40c258 EFLAGS: 00000246 ORIG_RAX: 000000000000010a RAX: ffffffffffffffda RBX: 0032656c69662f2e RCX: 00007f3e73ced469 RDX: 0000000020000200 RSI: 00000000ffffff9c RDI: 00000000200001c0 RBP: 0000000000000000 R08: 00007fff4d40c290 R09: 00007fff4d40c290 R10: 0023706f6f6c2f76 R11: 0000000000000246 R12: 00007fff4d40c27c R13: 0000000000000003 R14: 431bde82d7b634db R15: 00007fff4d40c2b0 </TASK> Calling ext4_xattr_ibody_find right after reading the inode with ext4_get_inode_loc will lead to a check of the validity of the xattrs, avoiding this problem.

In the Linux kernel, the following vulnerability has been resolved: drm/nouveau: fix a use-after-free in nouveau_gem_prime_import_sg_table() nouveau_bo_init() is backed by ttm_bo_init() and ferries its return code back to the caller. On failures, ttm will call nouveau_bo_del_ttm() and free the memory.Thus, when nouveau_bo_init() returns an error, the gem object has already been released. Then the call to nouveau_bo_ref() will use the freed "nvbo->bo" and lead to a use-after-free bug. We should delete the call to nouveau_bo_ref() to avoid the use-after-free.

A use-after-free flaw was found in the Linux kernel’s nouveau driver in how a user triggers a memory overflow that causes the nvkm_vma_tail function to fail. This flaw allows a local user to crash or potentially escalate their privileges on the system.

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: fs: fix UAF/GPF bug in nilfs_mdt_destroy In alloc_inode, inode_init_always() could return -ENOMEM if security_inode_alloc() fails, which causes inode->i_private uninitialized. Then nilfs_is_metadata_file_inode() returns true and nilfs_free_inode() wrongly calls nilfs_mdt_destroy(), which frees the uninitialized inode->i_private and leads to crashes(e.g., UAF/GPF). Fix this by moving security_inode_alloc just prior to this_cpu_inc(nr_inodes)

In the Linux kernel, the following vulnerability has been resolved: drm/panfrost: Fix GEM handle creation ref-counting panfrost_gem_create_with_handle() previously returned a BO but with the only reference being from the handle, which user space could in theory guess and release, causing a use-after-free. Additionally if the call to panfrost_gem_mapping_get() in panfrost_ioctl_create_bo() failed then a(nother) reference on the BO was dropped. The _create_with_handle() is a problematic pattern, so ditch it and instead create the handle in panfrost_ioctl_create_bo(). If the call to panfrost_gem_mapping_get() fails then this means that user space has indeed gone behind our back and freed the handle. In which case just return an error code.

In the Linux kernel, the following vulnerability has been resolved: ASoC: dapm: Fix UAF for snd_soc_pcm_runtime object When using kernel with the following extra config, - CONFIG_KASAN=y - CONFIG_KASAN_GENERIC=y - CONFIG_KASAN_INLINE=y - CONFIG_KASAN_VMALLOC=y - CONFIG_FRAME_WARN=4096 kernel detects that snd_pcm_suspend_all() access a freed 'snd_soc_pcm_runtime' object when the system is suspended, which leads to a use-after-free bug: [ 52.047746] BUG: KASAN: use-after-free in snd_pcm_suspend_all+0x1a8/0x270 [ 52.047765] Read of size 1 at addr ffff0000b9434d50 by task systemd-sleep/2330 [ 52.047785] Call trace: [ 52.047787] dump_backtrace+0x0/0x3c0 [ 52.047794] show_stack+0x34/0x50 [ 52.047797] dump_stack_lvl+0x68/0x8c [ 52.047802] print_address_description.constprop.0+0x74/0x2c0 [ 52.047809] kasan_report+0x210/0x230 [ 52.047815] __asan_report_load1_noabort+0x3c/0x50 [ 52.047820] snd_pcm_suspend_all+0x1a8/0x270 [ 52.047824] snd_soc_suspend+0x19c/0x4e0 The snd_pcm_sync_stop() has a NULL check on 'substream->runtime' before making any access. So we need to always set 'substream->runtime' to NULL everytime we kfree() it.

In the Linux kernel, the following vulnerability has been resolved: net: microchip: vcap: Fix use-after-free error in kunit test This is a clear use-after-free error. We remove it, and rely on checking the return code of vcap_del_rule.

In the Linux kernel, the following vulnerability has been resolved: net: fix use-after-free in tw_timer_handler A real world panic issue was found as follow in Linux 5.4. BUG: unable to handle page fault for address: ffffde49a863de28 PGD 7e6fe62067 P4D 7e6fe62067 PUD 7e6fe63067 PMD f51e064067 PTE 0 RIP: 0010:tw_timer_handler+0x20/0x40 Call Trace: <IRQ> call_timer_fn+0x2b/0x120 run_timer_softirq+0x1ef/0x450 __do_softirq+0x10d/0x2b8 irq_exit+0xc7/0xd0 smp_apic_timer_interrupt+0x68/0x120 apic_timer_interrupt+0xf/0x20 This issue was also reported since 2017 in the thread [1], unfortunately, the issue was still can be reproduced after fixing DCCP. The ipv4_mib_exit_net is called before tcp_sk_exit_batch when a net namespace is destroyed since tcp_sk_ops is registered befrore ipv4_mib_ops, which means tcp_sk_ops is in the front of ipv4_mib_ops in the list of pernet_list. There will be a use-after-free on net->mib.net_statistics in tw_timer_handler after ipv4_mib_exit_net if there are some inflight time-wait timers. This bug is not introduced by commit f2bf415cfed7 ("mib: add net to NET_ADD_STATS_BH") since the net_statistics is a global variable instead of dynamic allocation and freeing. Actually, commit 61a7e26028b9 ("mib: put net statistics on struct net") introduces the bug since it put net statistics on struct net and free it when net namespace is destroyed. Moving init_ipv4_mibs() to the front of tcp_init() to fix this bug and replace pr_crit() with panic() since continuing is meaningless when init_ipv4_mibs() fails. [1] https://groups.google.com/g/syzkaller/c/p1tn-_Kc6l4/m/smuL_FMAAgAJ?pli=1

In the Linux kernel, the following vulnerability has been resolved: aoe: fix the potential use-after-free problem in more places For fixing CVE-2023-6270, f98364e92662 ("aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts") makes tx() calling dev_put() instead of doing in aoecmd_cfg_pkts(). It avoids that the tx() runs into use-after-free. Then Nicolai Stange found more places in aoe have potential use-after-free problem with tx(). e.g. revalidate(), aoecmd_ata_rw(), resend(), probe() and aoecmd_cfg_rsp(). Those functions also use aoenet_xmit() to push packet to tx queue. So they should also use dev_hold() to increase the refcnt of skb->dev. On the other hand, moving dev_put() to tx() causes that the refcnt of skb->dev be reduced to a negative value, because corresponding dev_hold() are not called in revalidate(), aoecmd_ata_rw(), resend(), probe(), and aoecmd_cfg_rsp(). This patch fixed this issue.

In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix UAF by grabbing blkcg lock before destroying blkg pd KASAN reports a use-after-free report when doing fuzz test: [693354.104835] ================================================================== [693354.105094] BUG: KASAN: use-after-free in bfq_io_set_weight_legacy+0xd3/0x160 [693354.105336] Read of size 4 at addr ffff888be0a35664 by task sh/1453338 [693354.105607] CPU: 41 PID: 1453338 Comm: sh Kdump: loaded Not tainted 4.18.0-147 [693354.105610] Hardware name: Huawei 2288H V5/BC11SPSCB0, BIOS 0.81 07/02/2018 [693354.105612] Call Trace: [693354.105621] dump_stack+0xf1/0x19b [693354.105626] ? show_regs_print_info+0x5/0x5 [693354.105634] ? printk+0x9c/0xc3 [693354.105638] ? cpumask_weight+0x1f/0x1f [693354.105648] print_address_description+0x70/0x360 [693354.105654] kasan_report+0x1b2/0x330 [693354.105659] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105665] ? bfq_io_set_weight_legacy+0xd3/0x160 [693354.105670] bfq_io_set_weight_legacy+0xd3/0x160 [693354.105675] ? bfq_cpd_init+0x20/0x20 [693354.105683] cgroup_file_write+0x3aa/0x510 [693354.105693] ? ___slab_alloc+0x507/0x540 [693354.105698] ? cgroup_file_poll+0x60/0x60 [693354.105702] ? 0xffffffff89600000 [693354.105708] ? usercopy_abort+0x90/0x90 [693354.105716] ? mutex_lock+0xef/0x180 [693354.105726] kernfs_fop_write+0x1ab/0x280 [693354.105732] ? cgroup_file_poll+0x60/0x60 [693354.105738] vfs_write+0xe7/0x230 [693354.105744] ksys_write+0xb0/0x140 [693354.105749] ? __ia32_sys_read+0x50/0x50 [693354.105760] do_syscall_64+0x112/0x370 [693354.105766] ? syscall_return_slowpath+0x260/0x260 [693354.105772] ? do_page_fault+0x9b/0x270 [693354.105779] ? prepare_exit_to_usermode+0xf9/0x1a0 [693354.105784] ? enter_from_user_mode+0x30/0x30 [693354.105793] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.105875] Allocated by task 1453337: [693354.106001] kasan_kmalloc+0xa0/0xd0 [693354.106006] kmem_cache_alloc_node_trace+0x108/0x220 [693354.106010] bfq_pd_alloc+0x96/0x120 [693354.106015] blkcg_activate_policy+0x1b7/0x2b0 [693354.106020] bfq_create_group_hierarchy+0x1e/0x80 [693354.106026] bfq_init_queue+0x678/0x8c0 [693354.106031] blk_mq_init_sched+0x1f8/0x460 [693354.106037] elevator_switch_mq+0xe1/0x240 [693354.106041] elevator_switch+0x25/0x40 [693354.106045] elv_iosched_store+0x1a1/0x230 [693354.106049] queue_attr_store+0x78/0xb0 [693354.106053] kernfs_fop_write+0x1ab/0x280 [693354.106056] vfs_write+0xe7/0x230 [693354.106060] ksys_write+0xb0/0x140 [693354.106064] do_syscall_64+0x112/0x370 [693354.106069] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106114] Freed by task 1453336: [693354.106225] __kasan_slab_free+0x130/0x180 [693354.106229] kfree+0x90/0x1b0 [693354.106233] blkcg_deactivate_policy+0x12c/0x220 [693354.106238] bfq_exit_queue+0xf5/0x110 [693354.106241] blk_mq_exit_sched+0x104/0x130 [693354.106245] __elevator_exit+0x45/0x60 [693354.106249] elevator_switch_mq+0xd6/0x240 [693354.106253] elevator_switch+0x25/0x40 [693354.106257] elv_iosched_store+0x1a1/0x230 [693354.106261] queue_attr_store+0x78/0xb0 [693354.106264] kernfs_fop_write+0x1ab/0x280 [693354.106268] vfs_write+0xe7/0x230 [693354.106271] ksys_write+0xb0/0x140 [693354.106275] do_syscall_64+0x112/0x370 [693354.106280] entry_SYSCALL_64_after_hwframe+0x65/0xca [693354.106329] The buggy address belongs to the object at ffff888be0a35580 which belongs to the cache kmalloc-1k of size 1024 [693354.106736] The buggy address is located 228 bytes inside of 1024-byte region [ffff888be0a35580, ffff888be0a35980) [693354.107114] The buggy address belongs to the page: [693354.107273] page:ffffea002f828c00 count:1 mapcount:0 mapping:ffff888107c17080 index:0x0 compound_mapcount: 0 [693354.107606] flags: 0x17ffffc0008100(slab|head) [693354.107760] raw: 0017ffffc0008100 ffffea002fcbc808 ffffea0030bd3a08 ffff888107c17080 [693354.108020] r ---truncated---

There is a logic error in io_uring's implementation which can be used to trigger a use-after-free vulnerability leading to privilege escalation. In the io_prep_async_work function the assumption that the last io_grab_identity call cannot return false is not true, and in this case the function will use the init_cred or the previous linked requests identity to do operations instead of using the current identity. This can lead to reference counting issues causing use-after-free. We recommend upgrading past version 5.10.161.

In the Linux kernel, the following vulnerability has been resolved: efi: ssdt: Don't free memory if ACPI table was loaded successfully Amadeusz reports KASAN use-after-free errors introduced by commit 3881ee0b1edc ("efi: avoid efivars layer when loading SSDTs from variables"). The problem appears to be that the memory that holds the new ACPI table is now freed unconditionally, instead of only when the ACPI core reported a failure to load the table. So let's fix this, by omitting the kfree() on success.

In the Linux kernel, the following vulnerability has been resolved: drm/msm: fix use-after-free on probe deferral The bridge counter was never reset when tearing down the DRM device so that stale pointers to deallocated structures would be accessed on the next tear down (e.g. after a second late bind deferral). Given enough bridges and a few probe deferrals this could currently also lead to data beyond the bridge array being corrupted. Patchwork: https://patchwork.freedesktop.org/patch/502665/

In the Linux kernel, the following vulnerability has been resolved: ACPICA: Fix error code path in acpi_ds_call_control_method() A use-after-free in acpi_ps_parse_aml() after a failing invocaion of acpi_ds_call_control_method() is reported by KASAN [1] and code inspection reveals that next_walk_state pushed to the thread by acpi_ds_create_walk_state() is freed on errors, but it is not popped from the thread beforehand. Thus acpi_ds_get_current_walk_state() called by acpi_ps_parse_aml() subsequently returns it as the new walk state which is incorrect. To address this, make acpi_ds_call_control_method() call acpi_ds_pop_walk_state() to pop next_walk_state from the thread before returning an error.

In the Linux kernel, the following vulnerability has been resolved: nfsd: cancel nfsd_shrinker_work using sync mode in nfs4_state_shutdown_net In the normal case, when we excute `echo 0 > /proc/fs/nfsd/threads`, the function `nfs4_state_destroy_net` in `nfs4_state_shutdown_net` will release all resources related to the hashed `nfs4_client`. If the `nfsd_client_shrinker` is running concurrently, the `expire_client` function will first unhash this client and then destroy it. This can lead to the following warning. Additionally, numerous use-after-free errors may occur as well. nfsd_client_shrinker echo 0 > /proc/fs/nfsd/threads expire_client nfsd_shutdown_net unhash_client ... nfs4_state_shutdown_net /* won't wait shrinker exit */ /* cancel_work(&nn->nfsd_shrinker_work) * nfsd_file for this /* won't destroy unhashed client1 */ * client1 still alive nfs4_state_destroy_net */ nfsd_file_cache_shutdown /* trigger warning */ kmem_cache_destroy(nfsd_file_slab) kmem_cache_destroy(nfsd_file_mark_slab) /* release nfsd_file and mark */ __destroy_client ==================================================================== BUG nfsd_file (Not tainted): Objects remaining in nfsd_file on __kmem_cache_shutdown() -------------------------------------------------------------------- CPU: 4 UID: 0 PID: 764 Comm: sh Not tainted 6.12.0-rc3+ #1 dump_stack_lvl+0x53/0x70 slab_err+0xb0/0xf0 __kmem_cache_shutdown+0x15c/0x310 kmem_cache_destroy+0x66/0x160 nfsd_file_cache_shutdown+0xac/0x210 [nfsd] nfsd_destroy_serv+0x251/0x2a0 [nfsd] nfsd_svc+0x125/0x1e0 [nfsd] write_threads+0x16a/0x2a0 [nfsd] nfsctl_transaction_write+0x74/0xa0 [nfsd] vfs_write+0x1a5/0x6d0 ksys_write+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e ==================================================================== BUG nfsd_file_mark (Tainted: G B W ): Objects remaining nfsd_file_mark on __kmem_cache_shutdown() -------------------------------------------------------------------- dump_stack_lvl+0x53/0x70 slab_err+0xb0/0xf0 __kmem_cache_shutdown+0x15c/0x310 kmem_cache_destroy+0x66/0x160 nfsd_file_cache_shutdown+0xc8/0x210 [nfsd] nfsd_destroy_serv+0x251/0x2a0 [nfsd] nfsd_svc+0x125/0x1e0 [nfsd] write_threads+0x16a/0x2a0 [nfsd] nfsctl_transaction_write+0x74/0xa0 [nfsd] vfs_write+0x1a5/0x6d0 ksys_write+0xc1/0x160 do_syscall_64+0x5f/0x170 entry_SYSCALL_64_after_hwframe+0x76/0x7e To resolve this issue, cancel `nfsd_shrinker_work` using synchronous mode in nfs4_state_shutdown_net.

In the Linux kernel, the following vulnerability has been resolved: wifi: brcmfmac: fix use-after-free bug in brcmf_netdev_start_xmit() > ret = brcmf_proto_tx_queue_data(drvr, ifp->ifidx, skb); may be schedule, and then complete before the line > ndev->stats.tx_bytes += skb->len; [ 46.912801] ================================================================== [ 46.920552] BUG: KASAN: use-after-free in brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac] [ 46.928673] Read of size 4 at addr ffffff803f5882e8 by task systemd-resolve/328 [ 46.935991] [ 46.937514] CPU: 1 PID: 328 Comm: systemd-resolve Tainted: G O 5.4.199-[REDACTED] #1 [ 46.947255] Hardware name: [REDACTED] [ 46.954568] Call trace: [ 46.957037] dump_backtrace+0x0/0x2b8 [ 46.960719] show_stack+0x24/0x30 [ 46.964052] dump_stack+0x128/0x194 [ 46.967557] print_address_description.isra.0+0x64/0x380 [ 46.972877] __kasan_report+0x1d4/0x240 [ 46.976723] kasan_report+0xc/0x18 [ 46.980138] __asan_report_load4_noabort+0x18/0x20 [ 46.985027] brcmf_netdev_start_xmit+0x718/0x8c8 [brcmfmac] [ 46.990613] dev_hard_start_xmit+0x1bc/0xda0 [ 46.994894] sch_direct_xmit+0x198/0xd08 [ 46.998827] __qdisc_run+0x37c/0x1dc0 [ 47.002500] __dev_queue_xmit+0x1528/0x21f8 [ 47.006692] dev_queue_xmit+0x24/0x30 [ 47.010366] neigh_resolve_output+0x37c/0x678 [ 47.014734] ip_finish_output2+0x598/0x2458 [ 47.018927] __ip_finish_output+0x300/0x730 [ 47.023118] ip_output+0x2e0/0x430 [ 47.026530] ip_local_out+0x90/0x140 [ 47.030117] igmpv3_sendpack+0x14c/0x228 [ 47.034049] igmpv3_send_cr+0x384/0x6b8 [ 47.037895] igmp_ifc_timer_expire+0x4c/0x118 [ 47.042262] call_timer_fn+0x1cc/0xbe8 [ 47.046021] __run_timers+0x4d8/0xb28 [ 47.049693] run_timer_softirq+0x24/0x40 [ 47.053626] __do_softirq+0x2c0/0x117c [ 47.057387] irq_exit+0x2dc/0x388 [ 47.060715] __handle_domain_irq+0xb4/0x158 [ 47.064908] gic_handle_irq+0x58/0xb0 [ 47.068581] el0_irq_naked+0x50/0x5c [ 47.072162] [ 47.073665] Allocated by task 328: [ 47.077083] save_stack+0x24/0xb0 [ 47.080410] __kasan_kmalloc.isra.0+0xc0/0xe0 [ 47.084776] kasan_slab_alloc+0x14/0x20 [ 47.088622] kmem_cache_alloc+0x15c/0x468 [ 47.092643] __alloc_skb+0xa4/0x498 [ 47.096142] igmpv3_newpack+0x158/0xd78 [ 47.099987] add_grhead+0x210/0x288 [ 47.103485] add_grec+0x6b0/0xb70 [ 47.106811] igmpv3_send_cr+0x2e0/0x6b8 [ 47.110657] igmp_ifc_timer_expire+0x4c/0x118 [ 47.115027] call_timer_fn+0x1cc/0xbe8 [ 47.118785] __run_timers+0x4d8/0xb28 [ 47.122457] run_timer_softirq+0x24/0x40 [ 47.126389] __do_softirq+0x2c0/0x117c [ 47.130142] [ 47.131643] Freed by task 180: [ 47.134712] save_stack+0x24/0xb0 [ 47.138041] __kasan_slab_free+0x108/0x180 [ 47.142146] kasan_slab_free+0x10/0x18 [ 47.145904] slab_free_freelist_hook+0xa4/0x1b0 [ 47.150444] kmem_cache_free+0x8c/0x528 [ 47.154292] kfree_skbmem+0x94/0x108 [ 47.157880] consume_skb+0x10c/0x5a8 [ 47.161466] __dev_kfree_skb_any+0x88/0xa0 [ 47.165598] brcmu_pkt_buf_free_skb+0x44/0x68 [brcmutil] [ 47.171023] brcmf_txfinalize+0xec/0x190 [brcmfmac] [ 47.176016] brcmf_proto_bcdc_txcomplete+0x1c0/0x210 [brcmfmac] [ 47.182056] brcmf_sdio_sendfromq+0x8dc/0x1e80 [brcmfmac] [ 47.187568] brcmf_sdio_dpc+0xb48/0x2108 [brcmfmac] [ 47.192529] brcmf_sdio_dataworker+0xc8/0x238 [brcmfmac] [ 47.197859] process_one_work+0x7fc/0x1a80 [ 47.201965] worker_thread+0x31c/0xc40 [ 47.205726] kthread+0x2d8/0x370 [ 47.208967] ret_from_fork+0x10/0x18 [ 47.212546] [ 47.214051] The buggy address belongs to the object at ffffff803f588280 [ 47.214051] which belongs to the cache skbuff_head_cache of size 208 [ 47.227086] The buggy address is located 104 bytes inside of [ 47.227086] 208-byte region [ffffff803f588280, ffffff803f588350) [ 47.238814] The buggy address belongs to the page: [ 47.243618] page:ffffffff00dd6200 refcount:1 mapcou ---truncated---

In the Linux kernel, the following vulnerability has been resolved: staging: vme_user: Fix possible UAF in tsi148_dma_list_add Smatch report warning as follows: drivers/staging/vme_user/vme_tsi148.c:1757 tsi148_dma_list_add() warn: '&entry->list' not removed from list In tsi148_dma_list_add(), the error path "goto err_dma" will not remove entry->list from list->entries, but entry will be freed, then list traversal may cause UAF. Fix by removeing it from list->entries before free().

In the Linux kernel, the following vulnerability has been resolved: media: si470x: Fix use-after-free in si470x_int_in_callback() syzbot reported use-after-free in si470x_int_in_callback() [1]. This indicates that urb->context, which contains struct si470x_device object, is freed when si470x_int_in_callback() is called. The cause of this issue is that si470x_int_in_callback() is called for freed urb. si470x_usb_driver_probe() calls si470x_start_usb(), which then calls usb_submit_urb() and si470x_start(). If si470x_start_usb() fails, si470x_usb_driver_probe() doesn't kill urb, but it just frees struct si470x_device object, as depicted below: si470x_usb_driver_probe() ... si470x_start_usb() ... usb_submit_urb() retval = si470x_start() return retval if (retval < 0) free struct si470x_device object, but don't kill urb This patch fixes this issue by killing urb when si470x_start_usb() fails and urb is submitted. If si470x_start_usb() fails and urb is not submitted, i.e. submitting usb fails, it just frees struct si470x_device object.

In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: fix use-after-free We've already freed the assoc_data at this point, so need to use another copy of the AP (MLD) address instead.

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix possible uaf for 'bfqq->bic' Our test report a uaf for 'bfqq->bic' in 5.10: ================================================================== BUG: KASAN: use-after-free in bfq_select_queue+0x378/0xa30 CPU: 6 PID: 2318352 Comm: fsstress Kdump: loaded Not tainted 5.10.0-60.18.0.50.h602.kasan.eulerosv2r11.x86_64 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-20220320_160524-szxrtosci10000 04/01/2014 Call Trace: bfq_select_queue+0x378/0xa30 bfq_dispatch_request+0xe8/0x130 blk_mq_do_dispatch_sched+0x62/0xb0 __blk_mq_sched_dispatch_requests+0x215/0x2a0 blk_mq_sched_dispatch_requests+0x8f/0xd0 __blk_mq_run_hw_queue+0x98/0x180 __blk_mq_delay_run_hw_queue+0x22b/0x240 blk_mq_run_hw_queue+0xe3/0x190 blk_mq_sched_insert_requests+0x107/0x200 blk_mq_flush_plug_list+0x26e/0x3c0 blk_finish_plug+0x63/0x90 __iomap_dio_rw+0x7b5/0x910 iomap_dio_rw+0x36/0x80 ext4_dio_read_iter+0x146/0x190 [ext4] ext4_file_read_iter+0x1e2/0x230 [ext4] new_sync_read+0x29f/0x400 vfs_read+0x24e/0x2d0 ksys_read+0xd5/0x1b0 do_syscall_64+0x33/0x40 entry_SYSCALL_64_after_hwframe+0x61/0xc6 Commit 3bc5e683c67d ("bfq: Split shared queues on move between cgroups") changes that move process to a new cgroup will allocate a new bfqq to use, however, the old bfqq and new bfqq can point to the same bic: 1) Initial state, two process with io in the same cgroup. Process 1 Process 2 (BIC1) (BIC2) | Λ | Λ | | | | V | V | bfqq1 bfqq2 2) bfqq1 is merged to bfqq2. Process 1 Process 2 (BIC1) (BIC2) | | \-------------\| V bfqq1 bfqq2(coop) 3) Process 1 exit, then issue new io(denoce IOA) from Process 2. (BIC2) | Λ | | V | bfqq2(coop) 4) Before IOA is completed, move Process 2 to another cgroup and issue io. Process 2 (BIC2) Λ |\--------------\ | V bfqq2 bfqq3 Now that BIC2 points to bfqq3, while bfqq2 and bfqq3 both point to BIC2. If all the requests are completed, and Process 2 exit, BIC2 will be freed while there is no guarantee that bfqq2 will be freed before BIC2. Fix the problem by clearing bfqq->bic while bfqq is detached from bic.

In the Linux kernel, the following vulnerability has been resolved: dm cache: Fix UAF in destroy() Dm_cache also has the same UAF problem when dm_resume() and dm_destroy() are concurrent. Therefore, cancelling timer again in destroy().

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Fix use-after-free on amdgpu_bo_list mutex If amdgpu_cs_vm_handling returns r != 0, then it will unlock the bo_list_mutex inside the function amdgpu_cs_vm_handling and again on amdgpu_cs_parser_fini. This problem results in the following use-after-free problem: [ 220.280990] ------------[ cut here ]------------ [ 220.281000] refcount_t: underflow; use-after-free. [ 220.281019] WARNING: CPU: 1 PID: 3746 at lib/refcount.c:28 refcount_warn_saturate+0xba/0x110 [ 220.281029] ------------[ cut here ]------------ [ 220.281415] CPU: 1 PID: 3746 Comm: chrome:cs0 Tainted: G W L ------- --- 5.20.0-0.rc0.20220812git7ebfc85e2cd7.10.fc38.x86_64 #1 [ 220.281421] Hardware name: System manufacturer System Product Name/ROG STRIX X570-I GAMING, BIOS 4403 04/27/2022 [ 220.281426] RIP: 0010:refcount_warn_saturate+0xba/0x110 [ 220.281431] Code: 01 01 e8 79 4a 6f 00 0f 0b e9 42 47 a5 00 80 3d de 7e be 01 00 75 85 48 c7 c7 f8 98 8e 98 c6 05 ce 7e be 01 01 e8 56 4a 6f 00 <0f> 0b e9 1f 47 a5 00 80 3d b9 7e be 01 00 0f 85 5e ff ff ff 48 c7 [ 220.281437] RSP: 0018:ffffb4b0d18d7a80 EFLAGS: 00010282 [ 220.281443] RAX: 0000000000000026 RBX: 0000000000000003 RCX: 0000000000000000 [ 220.281448] RDX: 0000000000000001 RSI: ffffffff988d06dc RDI: 00000000ffffffff [ 220.281452] RBP: 00000000ffffffff R08: 0000000000000000 R09: ffffb4b0d18d7930 [ 220.281457] R10: 0000000000000003 R11: ffffa0672e2fffe8 R12: ffffa058ca360400 [ 220.281461] R13: ffffa05846c50a18 R14: 00000000fffffe00 R15: 0000000000000003 [ 220.281465] FS: 00007f82683e06c0(0000) GS:ffffa066e2e00000(0000) knlGS:0000000000000000 [ 220.281470] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 220.281475] CR2: 00003590005cc000 CR3: 00000001fca46000 CR4: 0000000000350ee0 [ 220.281480] Call Trace: [ 220.281485] <TASK> [ 220.281490] amdgpu_cs_ioctl+0x4e2/0x2070 [amdgpu] [ 220.281806] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] [ 220.282028] drm_ioctl_kernel+0xa4/0x150 [ 220.282043] drm_ioctl+0x21f/0x420 [ 220.282053] ? amdgpu_cs_find_mapping+0xe0/0xe0 [amdgpu] [ 220.282275] ? lock_release+0x14f/0x460 [ 220.282282] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 220.282290] ? _raw_spin_unlock_irqrestore+0x30/0x60 [ 220.282297] ? lockdep_hardirqs_on+0x7d/0x100 [ 220.282305] ? _raw_spin_unlock_irqrestore+0x40/0x60 [ 220.282317] amdgpu_drm_ioctl+0x4a/0x80 [amdgpu] [ 220.282534] __x64_sys_ioctl+0x90/0xd0 [ 220.282545] do_syscall_64+0x5b/0x80 [ 220.282551] ? futex_wake+0x6c/0x150 [ 220.282568] ? lock_is_held_type+0xe8/0x140 [ 220.282580] ? do_syscall_64+0x67/0x80 [ 220.282585] ? lockdep_hardirqs_on+0x7d/0x100 [ 220.282592] ? do_syscall_64+0x67/0x80 [ 220.282597] ? do_syscall_64+0x67/0x80 [ 220.282602] ? lockdep_hardirqs_on+0x7d/0x100 [ 220.282609] entry_SYSCALL_64_after_hwframe+0x63/0xcd [ 220.282616] RIP: 0033:0x7f8282a4f8bf [ 220.282639] Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00 [ 220.282644] RSP: 002b:00007f82683df410 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 220.282651] RAX: ffffffffffffffda RBX: 00007f82683df588 RCX: 00007f8282a4f8bf [ 220.282655] RDX: 00007f82683df4d0 RSI: 00000000c0186444 RDI: 0000000000000018 [ 220.282659] RBP: 00007f82683df4d0 R08: 00007f82683df5e0 R09: 00007f82683df4b0 [ 220.282663] R10: 00001d04000a0600 R11: 0000000000000246 R12: 00000000c0186444 [ 220.282667] R13: 0000000000000018 R14: 00007f82683df588 R15: 0000000000000003 [ 220.282689] </TASK> [ 220.282693] irq event stamp: 6232311 [ 220.282697] hardirqs last enabled at (6232319): [<ffffffff9718cd7e>] __up_console_sem+0x5e/0x70 [ 220.282704] hardirqs last disabled at (6232326): [<ffffffff9718cd63>] __up_console_sem+0x43/0x70 [ 220.282709] softirqs last enabled at (6232072): [<ffffffff970ff669>] __irq_exit_rcu+0xf9/0x170 [ 220.282716] softirqs last disabled at (6232061): [<ffffffff97 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ip6mr: fix UAF issue in ip6mr_sk_done() when addrconf_init_net() failed If the initialization fails in calling addrconf_init_net(), devconf_all is the pointer that has been released. Then ip6mr_sk_done() is called to release the net, accessing devconf->mc_forwarding directly causes invalid pointer access. The process is as follows: setup_net() ops_init() addrconf_init_net() all = kmemdup(...) ---> alloc "all" ... net->ipv6.devconf_all = all; __addrconf_sysctl_register() ---> failed ... kfree(all); ---> ipv6.devconf_all invalid ... ops_exit_list() ... ip6mr_sk_done() devconf = net->ipv6.devconf_all; //devconf is invalid pointer if (!devconf || !atomic_read(&devconf->mc_forwarding)) The following is the Call Trace information: BUG: KASAN: use-after-free in ip6mr_sk_done+0x112/0x3a0 Read of size 4 at addr ffff888075508e88 by task ip/14554 Call Trace: <TASK> dump_stack_lvl+0x8e/0xd1 print_report+0x155/0x454 kasan_report+0xba/0x1f0 kasan_check_range+0x35/0x1b0 ip6mr_sk_done+0x112/0x3a0 rawv6_close+0x48/0x70 inet_release+0x109/0x230 inet6_release+0x4c/0x70 sock_release+0x87/0x1b0 igmp6_net_exit+0x6b/0x170 ops_exit_list+0xb0/0x170 setup_net+0x7ac/0xbd0 copy_net_ns+0x2e6/0x6b0 create_new_namespaces+0x382/0xa50 unshare_nsproxy_namespaces+0xa6/0x1c0 ksys_unshare+0x3a4/0x7e0 __x64_sys_unshare+0x2d/0x40 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7f7963322547 </TASK> Allocated by task 14554: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 __kasan_kmalloc+0xa1/0xb0 __kmalloc_node_track_caller+0x4a/0xb0 kmemdup+0x28/0x60 addrconf_init_net+0x1be/0x840 ops_init+0xa5/0x410 setup_net+0x5aa/0xbd0 copy_net_ns+0x2e6/0x6b0 create_new_namespaces+0x382/0xa50 unshare_nsproxy_namespaces+0xa6/0x1c0 ksys_unshare+0x3a4/0x7e0 __x64_sys_unshare+0x2d/0x40 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Freed by task 14554: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_save_free_info+0x2a/0x40 ____kasan_slab_free+0x155/0x1b0 slab_free_freelist_hook+0x11b/0x220 __kmem_cache_free+0xa4/0x360 addrconf_init_net+0x623/0x840 ops_init+0xa5/0x410 setup_net+0x5aa/0xbd0 copy_net_ns+0x2e6/0x6b0 create_new_namespaces+0x382/0xa50 unshare_nsproxy_namespaces+0xa6/0x1c0 ksys_unshare+0x3a4/0x7e0 __x64_sys_unshare+0x2d/0x40 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0

In the Linux kernel, the following vulnerability has been resolved: ext4: block range must be validated before use in ext4_mb_clear_bb() Block range to free is validated in ext4_free_blocks() using ext4_inode_block_valid() and then it's passed to ext4_mb_clear_bb(). However in some situations on bigalloc file system the range might be adjusted after the validation in ext4_free_blocks() which can lead to troubles on corrupted file systems such as one found by syzkaller that resulted in the following BUG kernel BUG at fs/ext4/ext4.h:3319! PREEMPT SMP NOPTI CPU: 28 PID: 4243 Comm: repro Kdump: loaded Not tainted 5.19.0-rc6+ #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1.fc35 04/01/2014 RIP: 0010:ext4_free_blocks+0x95e/0xa90 Call Trace: <TASK> ? lock_timer_base+0x61/0x80 ? __es_remove_extent+0x5a/0x760 ? __mod_timer+0x256/0x380 ? ext4_ind_truncate_ensure_credits+0x90/0x220 ext4_clear_blocks+0x107/0x1b0 ext4_free_data+0x15b/0x170 ext4_ind_truncate+0x214/0x2c0 ? _raw_spin_unlock+0x15/0x30 ? ext4_discard_preallocations+0x15a/0x410 ? ext4_journal_check_start+0xe/0x90 ? __ext4_journal_start_sb+0x2f/0x110 ext4_truncate+0x1b5/0x460 ? __ext4_journal_start_sb+0x2f/0x110 ext4_evict_inode+0x2b4/0x6f0 evict+0xd0/0x1d0 ext4_enable_quotas+0x11f/0x1f0 ext4_orphan_cleanup+0x3de/0x430 ? proc_create_seq_private+0x43/0x50 ext4_fill_super+0x295f/0x3ae0 ? snprintf+0x39/0x40 ? sget_fc+0x19c/0x330 ? ext4_reconfigure+0x850/0x850 get_tree_bdev+0x16d/0x260 vfs_get_tree+0x25/0xb0 path_mount+0x431/0xa70 __x64_sys_mount+0xe2/0x120 do_syscall_64+0x5b/0x80 ? do_user_addr_fault+0x1e2/0x670 ? exc_page_fault+0x70/0x170 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7fdf4e512ace Fix it by making sure that the block range is properly validated before used every time it changes in ext4_free_blocks() or ext4_mb_clear_bb().

In the Linux kernel, the following vulnerability has been resolved: drm/meson: remove drm bridges at aggregate driver unbind time drm bridges added by meson_encoder_hdmi_init and meson_encoder_cvbs_init were not manually removed at module unload time, which caused dangling references to freed memory to remain linked in the global bridge_list. When loading the driver modules back in, the same functions would again call drm_bridge_add, and when traversing the global bridge_list, would end up peeking into freed memory. Once again KASAN revealed the problem: [ +0.000095] ============================================================= [ +0.000008] BUG: KASAN: use-after-free in __list_add_valid+0x9c/0x120 [ +0.000018] Read of size 8 at addr ffff00003da291f0 by task modprobe/2483 [ +0.000018] CPU: 3 PID: 2483 Comm: modprobe Tainted: G C O 5.19.0-rc6-lrmbkasan+ #1 [ +0.000011] Hardware name: Hardkernel ODROID-N2Plus (DT) [ +0.000008] Call trace: [ +0.000006] dump_backtrace+0x1ec/0x280 [ +0.000012] show_stack+0x24/0x80 [ +0.000008] dump_stack_lvl+0x98/0xd4 [ +0.000011] print_address_description.constprop.0+0x80/0x520 [ +0.000011] print_report+0x128/0x260 [ +0.000008] kasan_report+0xb8/0xfc [ +0.000008] __asan_report_load8_noabort+0x3c/0x50 [ +0.000009] __list_add_valid+0x9c/0x120 [ +0.000009] drm_bridge_add+0x6c/0x104 [drm] [ +0.000165] dw_hdmi_probe+0x1900/0x2360 [dw_hdmi] [ +0.000022] meson_dw_hdmi_bind+0x520/0x814 [meson_dw_hdmi] [ +0.000014] component_bind+0x174/0x520 [ +0.000012] component_bind_all+0x1a8/0x38c [ +0.000010] meson_drv_bind_master+0x5e8/0xb74 [meson_drm] [ +0.000032] meson_drv_bind+0x20/0x2c [meson_drm] [ +0.000027] try_to_bring_up_aggregate_device+0x19c/0x390 [ +0.000010] component_master_add_with_match+0x1c8/0x284 [ +0.000009] meson_drv_probe+0x274/0x280 [meson_drm] [ +0.000026] platform_probe+0xd0/0x220 [ +0.000009] really_probe+0x3ac/0xa80 [ +0.000009] __driver_probe_device+0x1f8/0x400 [ +0.000009] driver_probe_device+0x68/0x1b0 [ +0.000009] __driver_attach+0x20c/0x480 [ +0.000008] bus_for_each_dev+0x114/0x1b0 [ +0.000009] driver_attach+0x48/0x64 [ +0.000008] bus_add_driver+0x390/0x564 [ +0.000009] driver_register+0x1a8/0x3e4 [ +0.000009] __platform_driver_register+0x6c/0x94 [ +0.000008] meson_drm_platform_driver_init+0x3c/0x1000 [meson_drm] [ +0.000027] do_one_initcall+0xc4/0x2b0 [ +0.000011] do_init_module+0x154/0x570 [ +0.000011] load_module+0x1a78/0x1ea4 [ +0.000008] __do_sys_init_module+0x184/0x1cc [ +0.000009] __arm64_sys_init_module+0x78/0xb0 [ +0.000009] invoke_syscall+0x74/0x260 [ +0.000009] el0_svc_common.constprop.0+0xcc/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000012] el0t_64_sync_handler+0x11c/0x150 [ +0.000008] el0t_64_sync+0x18c/0x190 [ +0.000016] Allocated by task 879: [ +0.000008] kasan_save_stack+0x2c/0x5c [ +0.000011] __kasan_kmalloc+0x90/0xd0 [ +0.000007] __kmalloc+0x278/0x4a0 [ +0.000011] mpi_resize+0x13c/0x1d0 [ +0.000011] mpi_powm+0xd24/0x1570 [ +0.000009] rsa_enc+0x1a4/0x30c [ +0.000009] pkcs1pad_verify+0x3f0/0x580 [ +0.000009] public_key_verify_signature+0x7a8/0xba4 [ +0.000010] public_key_verify_signature_2+0x40/0x60 [ +0.000008] verify_signature+0xb4/0x114 [ +0.000008] pkcs7_validate_trust_one.constprop.0+0x3b8/0x574 [ +0.000009] pkcs7_validate_trust+0xb8/0x15c [ +0.000008] verify_pkcs7_message_sig+0xec/0x1b0 [ +0.000012] verify_pkcs7_signature+0x78/0xac [ +0.000007] mod_verify_sig+0x110/0x190 [ +0.000009] module_sig_check+0x114/0x1e0 [ +0.000009] load_module+0xa0/0x1ea4 [ +0.000008] __do_sys_init_module+0x184/0x1cc [ +0.000008] __arm64_sys_init_module+0x78/0xb0 [ +0.000008] invoke_syscall+0x74/0x260 [ +0.000009] el0_svc_common.constprop.0+0x1a8/0x260 [ +0.000008] do_el0_svc+0x50/0x70 [ +0.000007] el0_svc+0x68/0x1a0 [ +0.000009] el0t_64_sync_handler+0x11c/0x150 [ +0.000009] el0t_64 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Fix null pointer dereference after failing to issue FLOGI and PLOGI If lpfc_issue_els_flogi() fails and returns non-zero status, the node reference count is decremented to trigger the release of the nodelist structure. However, if there is a prior registration or dev-loss-evt work pending, the node may be released prematurely. When dev-loss-evt completes, the released node is referenced causing a use-after-free null pointer dereference. Similarly, when processing non-zero ELS PLOGI completion status in lpfc_cmpl_els_plogi(), the ndlp flags are checked for a transport registration before triggering node removal. If dev-loss-evt work is pending, the node may be released prematurely and a subsequent call to lpfc_dev_loss_tmo_handler() results in a use after free ndlp dereference. Add test for pending dev-loss before decrementing the node reference count for FLOGI, PLOGI, PRLI, and ADISC handling.

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scpi: Ensure scpi_info is not assigned if the probe fails When scpi probe fails, at any point, we need to ensure that the scpi_info is not set and will remain NULL until the probe succeeds. If it is not taken care, then it could result use-after-free as the value is exported via get_scpi_ops() and could refer to a memory allocated via devm_kzalloc() but freed when the probe fails.

In the Linux kernel, the following vulnerability has been resolved: ASoC: core: Fix use-after-free in snd_soc_exit() KASAN reports a use-after-free: BUG: KASAN: use-after-free in device_del+0xb5b/0xc60 Read of size 8 at addr ffff888008655050 by task rmmod/387 CPU: 2 PID: 387 Comm: rmmod Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Call Trace: <TASK> dump_stack_lvl+0x79/0x9a print_report+0x17f/0x47b kasan_report+0xbb/0xf0 device_del+0xb5b/0xc60 platform_device_del.part.0+0x24/0x200 platform_device_unregister+0x2e/0x40 snd_soc_exit+0xa/0x22 [snd_soc_core] __do_sys_delete_module.constprop.0+0x34f/0x5b0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd ... </TASK> It's bacause in snd_soc_init(), snd_soc_util_init() is possble to fail, but its ret is ignored, which makes soc_dummy_dev unregistered twice. snd_soc_init() snd_soc_util_init() platform_device_register_simple(soc_dummy_dev) platform_driver_register() # fail platform_device_unregister(soc_dummy_dev) platform_driver_register() # success ... snd_soc_exit() snd_soc_util_exit() # soc_dummy_dev will be unregistered for second time To fix it, handle error and stop snd_soc_init() when util_init() fail. Also clean debugfs when util_init() or driver_register() fail.

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: fix dangling sco_conn and use-after-free in sco_sock_timeout Connecting the same socket twice consecutively in sco_sock_connect() could lead to a race condition where two sco_conn objects are created but only one is associated with the socket. If the socket is closed before the SCO connection is established, the timer associated with the dangling sco_conn object won't be canceled. As the sock object is being freed, the use-after-free problem happens when the timer callback function sco_sock_timeout() accesses the socket. Here's the call trace: dump_stack+0x107/0x163 ? refcount_inc+0x1c/ print_address_description.constprop.0+0x1c/0x47e ? refcount_inc+0x1c/0x7b kasan_report+0x13a/0x173 ? refcount_inc+0x1c/0x7b check_memory_region+0x132/0x139 refcount_inc+0x1c/0x7b sco_sock_timeout+0xb2/0x1ba process_one_work+0x739/0xbd1 ? cancel_delayed_work+0x13f/0x13f ? __raw_spin_lock_init+0xf0/0xf0 ? to_kthread+0x59/0x85 worker_thread+0x593/0x70e kthread+0x346/0x35a ? drain_workqueue+0x31a/0x31a ? kthread_bind+0x4b/0x4b ret_from_fork+0x1f/0x30

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix KASAN use-after-free Read in compute_effective_progs Syzbot found a Use After Free bug in compute_effective_progs(). The reproducer creates a number of BPF links, and causes a fault injected alloc to fail, while calling bpf_link_detach on them. Link detach triggers the link to be freed by bpf_link_free(), which calls __cgroup_bpf_detach() and update_effective_progs(). If the memory allocation in this function fails, the function restores the pointer to the bpf_cgroup_link on the cgroup list, but the memory gets freed just after it returns. After this, every subsequent call to update_effective_progs() causes this already deallocated pointer to be dereferenced in prog_list_length(), and triggers KASAN UAF error. To fix this issue don't preserve the pointer to the prog or link in the list, but remove it and replace it with a dummy prog without shrinking the table. The subsequent call to __cgroup_bpf_detach() or __cgroup_bpf_detach() will correct it.

In the Linux kernel, the following vulnerability has been resolved: android: binder: stop saving a pointer to the VMA Do not record a pointer to a VMA outside of the mmap_lock for later use. This is unsafe and there are a number of failure paths *after* the recorded VMA pointer may be freed during setup. There is no callback to the driver to clear the saved pointer from generic mm code. Furthermore, the VMA pointer may become stale if any number of VMA operations end up freeing the VMA so saving it was fragile to being with. Instead, change the binder_alloc struct to record the start address of the VMA and use vma_lookup() to get the vma when needed. Add lockdep mmap_lock checks on updates to the vma pointer to ensure the lock is held and depend on that lock for synchronization of readers and writers - which was already the case anyways, so the smp_wmb()/smp_rmb() was not necessary. [akpm@linux-foundation.org: fix drivers/android/binder_alloc_selftest.c]

In the Linux kernel, the following vulnerability has been resolved: jbd2: fix potential use-after-free in jbd2_fc_wait_bufs In 'jbd2_fc_wait_bufs' use 'bh' after put buffer head reference count which may lead to use-after-free. So judge buffer if uptodate before put buffer head reference count.

In the Linux kernel, the following vulnerability has been resolved: idpf: fix memory leaks and crashes while performing a soft reset The second tagged commit introduced a UAF, as it removed restoring q_vector->vport pointers after reinitializating the structures. This is due to that all queue allocation functions are performed here with the new temporary vport structure and those functions rewrite the backpointers to the vport. Then, this new struct is freed and the pointers start leading to nowhere. But generally speaking, the current logic is very fragile. It claims to be more reliable when the system is low on memory, but in fact, it consumes two times more memory as at the moment of running this function, there are two vports allocated with their queues and vectors. Moreover, it claims to prevent the driver from running into "bad state", but in fact, any error during the rebuild leaves the old vport in the partially allocated state. Finally, if the interface is down when the function is called, it always allocates a new queue set, but when the user decides to enable the interface later on, vport_open() allocates them once again, IOW there's a clear memory leak here. Just don't allocate a new queue set when performing a reset, that solves crashes and memory leaks. Readd the old queue number and reopen the interface on rollback - that solves limbo states when the device is left disabled and/or without HW queues enabled.

In the Linux kernel, the following vulnerability has been resolved: ASoC: sof_es8336: fix possible use-after-free in sof_es8336_remove() sof_es8336_remove() calls cancel_delayed_work(). However, that function does not wait until the work function finishes. This means that the callback function may still be running after the driver's remove function has finished, which would result in a use-after-free. Fix by calling cancel_delayed_work_sync(), which ensures that the work is properly cancelled, no longer running, and unable to re-schedule itself.

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: do not allow CHAIN_ID to refer to another table When doing lookups for chains on the same batch by using its ID, a chain from a different table can be used. If a rule is added to a table but refers to a chain in a different table, it will be linked to the chain in table2, but would have expressions referring to objects in table1. Then, when table1 is removed, the rule will not be removed as its linked to a chain in table2. When expressions in the rule are processed or removed, that will lead to a use-after-free. When looking for chains by ID, use the table that was used for the lookup by name, and only return chains belonging to that same table.

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for bfqq in bfq_exit_icq_bfqq Commit 64dc8c732f5c ("block, bfq: fix possible uaf for 'bfqq->bic'") will access 'bic->bfqq' in bic_set_bfqq(), however, bfq_exit_icq_bfqq() can free bfqq first, and then call bic_set_bfqq(), which will cause uaf. Fix the problem by moving bfq_exit_bfqq() behind bic_set_bfqq().

In the Linux kernel, the following vulnerability has been resolved: kprobes: Skip clearing aggrprobe's post_handler in kprobe-on-ftrace case In __unregister_kprobe_top(), if the currently unregistered probe has post_handler but other child probes of the aggrprobe do not have post_handler, the post_handler of the aggrprobe is cleared. If this is a ftrace-based probe, there is a problem. In later calls to disarm_kprobe(), we will use kprobe_ftrace_ops because post_handler is NULL. But we're armed with kprobe_ipmodify_ops. This triggers a WARN in __disarm_kprobe_ftrace() and may even cause use-after-free: Failed to disarm kprobe-ftrace at kernel_clone+0x0/0x3c0 (error -2) WARNING: CPU: 5 PID: 137 at kernel/kprobes.c:1135 __disarm_kprobe_ftrace.isra.21+0xcf/0xe0 Modules linked in: testKprobe_007(-) CPU: 5 PID: 137 Comm: rmmod Not tainted 6.1.0-rc4-dirty #18 [...] Call Trace: <TASK> __disable_kprobe+0xcd/0xe0 __unregister_kprobe_top+0x12/0x150 ? mutex_lock+0xe/0x30 unregister_kprobes.part.23+0x31/0xa0 unregister_kprobe+0x32/0x40 __x64_sys_delete_module+0x15e/0x260 ? do_user_addr_fault+0x2cd/0x6b0 do_syscall_64+0x3a/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...] For the kprobe-on-ftrace case, we keep the post_handler setting to identify this aggrprobe armed with kprobe_ipmodify_ops. This way we can disarm it correctly.