BUG: sleeping function called from invalid context in cancel_delayed_work_sync

Status: upstream: reported C repro on 2026/08/05 22:45
Subsystems: usb
[Documentation on labels]
Reported-by: syzbot+1ee4f3b9228e35f14677@syzkaller.appspotmail.com
First crash: 1d17h, last: 22h56m
✨ AI Jobs (2)
ID Workflow Result Correct Bug Created Started Finished Revision
f105b557 patching BUG: sleeping function called from invalid context in cancel_delayed_work_sync 2026/08/06 06:48
f50558c5 assessment-security 💥 BUG: sleeping function called from invalid context in cancel_delayed_work_sync 2026/08/05 00:03 2026/08/05 00:03 2026/08/05 00:03 d4abbeac
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [usb?] BUG: sleeping function called from invalid context in cancel_delayed_work_sync 0 (1) 2026/08/05 22:45
Similar bugs (5)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 KASAN: use-after-free Read in consume_skb 19 syz, C 73 381d 1050d 0/2 auto-obsoleted due to no activity on 2025/10/29 05:12
upstream KASAN: slab-use-after-free Read in consume_skb bpf net 19 syz, C error 6 1065d 1065d 0/29 closed as invalid on 2023/10/04 10:50
android-6-1 KASAN: use-after-free Read in consume_skb 19 syz, C error done 4 1002d 1061d 0/2 auto-obsoleted due to no activity on 2024/02/15 15:09
linux-5.15 KASAN: use-after-free Read in consume_skb origin:lts-only 19 syz, C done 6 427d 726d 0/3 auto-obsoleted due to no activity on 2025/09/13 01:43
upstream KASAN: use-after-free Read in consume_skb bpf net 19 syz, C done inconclusive 33 1481d 1760d 0/29 closed as invalid on 2022/10/12 18:37

Sample crash report:
BUG: sleeping function called from invalid context at kernel/workqueue.c:4487
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 2983, name: syz-execprog
preempt_count: 100, expected: 0
RCU nest depth: 0, expected: 0
1 lock held by syz-execprog/2983:
 #0: ffffc90000537be8 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11f/0x610 kernel/time/timer.c:1745
Preemption disabled at:
[<ffffffff81772c20>] softirq_handle_begin kernel/softirq.c:463 [inline]
[<ffffffff81772c20>] handle_softirqs+0xf0/0x990 kernel/softirq.c:598
CPU: 0 UID: 0 PID: 2983 Comm: syz-execprog Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 __might_resched.cold+0x1ec/0x232 kernel/sched/core.c:9197
 __cancel_work_sync kernel/workqueue.c:4487 [inline]
 cancel_delayed_work_sync+0xb8/0xf0 kernel/workqueue.c:4568
 mmc_free_host+0x19/0x30 drivers/mmc/core/host.c:700
 vub300_delete drivers/mmc/host/vub300.c:379 [inline]
 kref_put include/linux/kref.h:65 [inline]
 vub300_inactivity_timer_expired drivers/mmc/host/vub300.c:747 [inline]
 vub300_inactivity_timer_expired+0x42f/0x550 drivers/mmc/host/vub300.c:742
 call_timer_fn+0x19a/0x610 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x757/0xb00 kernel/time/timer.c:2374
 __run_timer_base kernel/time/timer.c:2386 [inline]
 __run_timer_base kernel/time/timer.c:2378 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2395
 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405
 handle_softirqs+0x1dd/0x990 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x160/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0x42/0xb0 arch/x86/kernel/apic/apic.c:1062
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0033:0x476b32
Code: 0c 0f b6 48 09 f6 c1 01 74 20 f6 c1 04 74 1b 48 83 78 18 00 7e 14 83 e1 fb 88 48 09 48 8b 48 48 ba ff ff ff ff f0 0f c1 51 24 <0f> b6 48 09 90 f6 c1 01 75 1d 48 83 78 18 00 7e 16 80 78 0a 00 74
RSP: 002b:00003a4df9efdec8 EFLAGS: 00000257
RAX: 00003a4dfa0fc2b0 RBX: 0000000000000001 RCX: 00003a4df9ec1570
RDX: 0000000000000001 RSI: 0000000000000080 RDI: 0000000000000018
RBP: 00003a4df9efdee8 R08: 00003a4dfa0fc1c0 R09: 0000000000000000
R10: 00003a4dfe15c838 R11: 00003a4dfe15e180 R12: 00003a4dfe15e180
R13: 0000000000000001 R14: 00003a4dfa37cf00 R15: 0000000000000001
 </TASK>
BUG: scheduling while atomic: syz-execprog/2983/0x00000101
1 lock held by syz-execprog/2983:
 #0: ffffc90000537be8 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11f/0x610 kernel/time/timer.c:1745
Modules linked in:
Preemption disabled at:
[<ffffffff81772c20>] softirq_handle_begin kernel/softirq.c:463 [inline]
[<ffffffff81772c20>] handle_softirqs+0xf0/0x990 kernel/softirq.c:598

Crashes (20):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/04 19:22 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 5d5fd841c346 d4abbeac .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-usb BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 18:05 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 5d5fd841c346 d4abbeac .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-usb BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/05 07:55 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/05 07:55 upstream c21bb4193868 b3eac40e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/05 02:32 upstream c21bb4193868 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/05 02:32 upstream c21bb4193868 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 20:33 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:30 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:19 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:19 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:17 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:16 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:16 upstream 848acc8ffe1b d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 17:22 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:59 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:55 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:31 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 15:18 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 14:19 upstream 848acc8ffe1b 3c5eaa21 .config console log report info [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu-upstream-386 BUG: sleeping function called from invalid context in cancel_delayed_work_sync
2026/08/04 13:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 7235a3e71949 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 BUG: sleeping function called from invalid context in cancel_delayed_work_sync
* Struck through repros no longer work on HEAD.