In the Linux kernel, the following vulnerability has been resolved:

media: i2c: tc358743: Fix use-after-free bugs caused by orphan timer in probe

The state->timer is a cyclic timer that schedules work_i2c_poll and
delayed_work_enable_hotplug, while rearming itself. Using timer_delete()
fails to guarantee the timer isn't still running when destroyed, similarly
cancel_delayed_work() cannot ensure delayed_work_enable_hotplug has
terminated if already executing. During probe failure after timer
initialization, these may continue running as orphans and reference the
already-freed tc358743_state object through tc358743_irq_poll_timer.

The following is the trace captured by KASAN.

BUG: KASAN: slab-use-after-free in __run_timer_base.part.0+0x7d7/0x8c0
Write of size 8 at addr ffff88800ded83c8 by task swapper/1/0
...
Call Trace:
<IRQ>
dump_stack_lvl+0x55/0x70
print_report+0xcf/0x610
? __pfx_sched_balance_find_src_group+0x10/0x10
? __run_timer_base.part.0+0x7d7/0x8c0
kasan_report+0xb8/0xf0
? __run_timer_base.part.0+0x7d7/0x8c0
__run_timer_base.part.0+0x7d7/0x8c0
? rcu_sched_clock_irq+0xb06/0x27d0
? __pfx___run_timer_base.part.0+0x10/0x10
? try_to_wake_up+0xb15/0x1960
? tmigr_update_events+0x280/0x740
? _raw_spin_lock_irq+0x80/0xe0
? __pfx__raw_spin_lock_irq+0x10/0x10
tmigr_handle_remote_up+0x603/0x7e0
? __pfx_tmigr_handle_remote_up+0x10/0x10
? sched_balance_trigger+0x98/0x9f0
? sched_tick+0x221/0x5a0
? _raw_spin_lock_irq+0x80/0xe0
? __pfx__raw_spin_lock_irq+0x10/0x10
? tick_nohz_handler+0x339/0x440
? __pfx_tmigr_handle_remote_up+0x10/0x10
__walk_groups.isra.0+0x42/0x150
tmigr_handle_remote+0x1f4/0x2e0
? __pfx_tmigr_handle_remote+0x10/0x10
? ktime_get+0x60/0x140
? lapic_next_event+0x11/0x20
? clockevents_program_event+0x1d4/0x2a0
? hrtimer_interrupt+0x322/0x780
handle_softirqs+0x16a/0x550
irq_exit_rcu+0xaf/0xe0
sysvec_apic_timer_interrupt+0x70/0x80
</IRQ>
...

Allocated by task 141:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
__kasan_kmalloc+0x7f/0x90
__kmalloc_node_track_caller_noprof+0x198/0x430
devm_kmalloc+0x7b/0x1e0
tc358743_probe+0xb7/0x610 i2c_device_probe+0x51d/0x880
really_probe+0x1ca/0x5c0
__driver_probe_device+0x248/0x310
driver_probe_device+0x44/0x120
__device_attach_driver+0x174/0x220
bus_for_each_drv+0x100/0x190
__device_attach+0x206/0x370
bus_probe_device+0x123/0x170
device_add+0xd25/0x1470
i2c_new_client_device+0x7a0/0xcd0
do_one_initcall+0x89/0x300
do_init_module+0x29d/0x7f0
load_module+0x4f48/0x69e0
init_module_from_file+0xe4/0x150
idempotent_init_module+0x320/0x670
__x64_sys_finit_module+0xbd/0x120
do_syscall_64+0xac/0x280
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 141:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3a/0x60
__kasan_slab_free+0x3f/0x50
kfree+0x137/0x370
release_nodes+0xa4/0x100
devres_release_group+0x1b2/0x380
i2c_device_probe+0x694/0x880
really_probe+0x1ca/0x5c0
__driver_probe_device+0x248/0x310
driver_probe_device+0x44/0x120
__device_attach_driver+0x174/0x220
bus_for_each_drv+0x100/0x190
__device_attach+0x206/0x370
bus_probe_device+0x123/0x170
device_add+0xd25/0x1470
i2c_new_client_device+0x7a0/0xcd0
do_one_initcall+0x89/0x300
do_init_module+0x29d/0x7f0
load_module+0x4f48/0x69e0
init_module_from_file+0xe4/0x150
idempotent_init_module+0x320/0x670
__x64_sys_finit_module+0xbd/0x120
do_syscall_64+0xac/0x280
entry_SYSCALL_64_after_hwframe+0x77/0x7f
...

Replace timer_delete() with timer_delete_sync() and cancel_delayed_work()
with cancel_delayed_work_sync() to ensure proper termination of timer and
work items before resource cleanup.

This bug was initially identified through static analysis. For reproduction
and testing, I created a functional emulation of the tc358743 device via a
kernel module and introduced faults through the debugfs interface.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Wed, 15 Oct 2025 10:45:00 +0000


Wed, 15 Oct 2025 08:15:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: media: i2c: tc358743: Fix use-after-free bugs caused by orphan timer in probe The state->timer is a cyclic timer that schedules work_i2c_poll and delayed_work_enable_hotplug, while rearming itself. Using timer_delete() fails to guarantee the timer isn't still running when destroyed, similarly cancel_delayed_work() cannot ensure delayed_work_enable_hotplug has terminated if already executing. During probe failure after timer initialization, these may continue running as orphans and reference the already-freed tc358743_state object through tc358743_irq_poll_timer. The following is the trace captured by KASAN. BUG: KASAN: slab-use-after-free in __run_timer_base.part.0+0x7d7/0x8c0 Write of size 8 at addr ffff88800ded83c8 by task swapper/1/0 ... Call Trace: <IRQ> dump_stack_lvl+0x55/0x70 print_report+0xcf/0x610 ? __pfx_sched_balance_find_src_group+0x10/0x10 ? __run_timer_base.part.0+0x7d7/0x8c0 kasan_report+0xb8/0xf0 ? __run_timer_base.part.0+0x7d7/0x8c0 __run_timer_base.part.0+0x7d7/0x8c0 ? rcu_sched_clock_irq+0xb06/0x27d0 ? __pfx___run_timer_base.part.0+0x10/0x10 ? try_to_wake_up+0xb15/0x1960 ? tmigr_update_events+0x280/0x740 ? _raw_spin_lock_irq+0x80/0xe0 ? __pfx__raw_spin_lock_irq+0x10/0x10 tmigr_handle_remote_up+0x603/0x7e0 ? __pfx_tmigr_handle_remote_up+0x10/0x10 ? sched_balance_trigger+0x98/0x9f0 ? sched_tick+0x221/0x5a0 ? _raw_spin_lock_irq+0x80/0xe0 ? __pfx__raw_spin_lock_irq+0x10/0x10 ? tick_nohz_handler+0x339/0x440 ? __pfx_tmigr_handle_remote_up+0x10/0x10 __walk_groups.isra.0+0x42/0x150 tmigr_handle_remote+0x1f4/0x2e0 ? __pfx_tmigr_handle_remote+0x10/0x10 ? ktime_get+0x60/0x140 ? lapic_next_event+0x11/0x20 ? clockevents_program_event+0x1d4/0x2a0 ? hrtimer_interrupt+0x322/0x780 handle_softirqs+0x16a/0x550 irq_exit_rcu+0xaf/0xe0 sysvec_apic_timer_interrupt+0x70/0x80 </IRQ> ... Allocated by task 141: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 __kasan_kmalloc+0x7f/0x90 __kmalloc_node_track_caller_noprof+0x198/0x430 devm_kmalloc+0x7b/0x1e0 tc358743_probe+0xb7/0x610 i2c_device_probe+0x51d/0x880 really_probe+0x1ca/0x5c0 __driver_probe_device+0x248/0x310 driver_probe_device+0x44/0x120 __device_attach_driver+0x174/0x220 bus_for_each_drv+0x100/0x190 __device_attach+0x206/0x370 bus_probe_device+0x123/0x170 device_add+0xd25/0x1470 i2c_new_client_device+0x7a0/0xcd0 do_one_initcall+0x89/0x300 do_init_module+0x29d/0x7f0 load_module+0x4f48/0x69e0 init_module_from_file+0xe4/0x150 idempotent_init_module+0x320/0x670 __x64_sys_finit_module+0xbd/0x120 do_syscall_64+0xac/0x280 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 141: kasan_save_stack+0x24/0x50 kasan_save_track+0x14/0x30 kasan_save_free_info+0x3a/0x60 __kasan_slab_free+0x3f/0x50 kfree+0x137/0x370 release_nodes+0xa4/0x100 devres_release_group+0x1b2/0x380 i2c_device_probe+0x694/0x880 really_probe+0x1ca/0x5c0 __driver_probe_device+0x248/0x310 driver_probe_device+0x44/0x120 __device_attach_driver+0x174/0x220 bus_for_each_drv+0x100/0x190 __device_attach+0x206/0x370 bus_probe_device+0x123/0x170 device_add+0xd25/0x1470 i2c_new_client_device+0x7a0/0xcd0 do_one_initcall+0x89/0x300 do_init_module+0x29d/0x7f0 load_module+0x4f48/0x69e0 init_module_from_file+0xe4/0x150 idempotent_init_module+0x320/0x670 __x64_sys_finit_module+0xbd/0x120 do_syscall_64+0xac/0x280 entry_SYSCALL_64_after_hwframe+0x77/0x7f ... Replace timer_delete() with timer_delete_sync() and cancel_delayed_work() with cancel_delayed_work_sync() to ensure proper termination of timer and work items before resource cleanup. This bug was initially identified through static analysis. For reproduction and testing, I created a functional emulation of the tc358743 device via a kernel module and introduced faults through the debugfs interface.
Title media: i2c: tc358743: Fix use-after-free bugs caused by orphan timer in probe
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2025-10-15T10:22:25.496Z

Reserved: 2025-04-16T07:20:57.151Z

Link: CVE-2025-39995

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2025-10-15T08:15:37.690

Modified: 2025-10-15T11:15:37.343

Link: CVE-2025-39995

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.