============================= [ BUG: Invalid wait context ] 6.13.0-syzkaller-07644-gc2da8b3f914f #0 Not tainted ----------------------------- syz.0.0/5323 is trying to lock: ffff88801fc3aaf0 (batched_entropy_u8.lock){-.-.}-{3:3}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ffff88801fc3aaf0 (batched_entropy_u8.lock){-.-.}-{3:3}, at: get_random_u8+0x1a0/0xaa0 drivers/char/random.c:551 other info that might help us debug this: context-{2:2} 1 lock held by syz.0.0/5323: #0: ffff88801ac6a9e0 (&mm->mmap_lock){++++}-{4:4}, at: __might_fault+0xaa/0x120 mm/memory.c:6770 stack backtrace: CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 Not tainted 6.13.0-syzkaller-07644-gc2da8b3f914f #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: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_lock_invalid_wait_context kernel/locking/lockdep.c:4828 [inline] check_wait_context kernel/locking/lockdep.c:4900 [inline] __lock_acquire+0x15a8/0x2100 kernel/locking/lockdep.c:5178 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] get_random_u8+0x1bd/0xaa0 drivers/char/random.c:551 get_random_u32_below include/linux/random.h:78 [inline] kfence_guarded_alloc+0x9c/0xcd0 mm/kfence/core.c:421 __kfence_alloc+0x344/0x370 mm/kfence/core.c:1136 kfence_alloc include/linux/kfence.h:129 [inline] slab_alloc_node mm/slub.c:4152 [inline] __kmalloc_cache_noprof+0x2dd/0x390 mm/slub.c:4324 kmalloc_noprof include/linux/slab.h:901 [inline] add_stack_record_to_list mm/page_owner.c:172 [inline] inc_stack_record_count mm/page_owner.c:214 [inline] __set_page_owner+0x55f/0x800 mm/page_owner.c:329 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1558 prep_new_page mm/page_alloc.c:1566 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3476 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4753 alloc_pages_mpol_noprof+0x3e1/0x780 mm/mempolicy.c:2269 stack_depot_save_flags+0x72d/0x940 lib/stackdepot.c:627 kasan_save_stack+0x4f/0x60 mm/kasan/common.c:48 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:544 task_work_add+0xd9/0x490 kernel/task_work.c:77 __run_posix_cpu_timers kernel/time/posix-cpu-timers.c:1223 [inline] run_posix_cpu_timers+0x6ac/0x810 kernel/time/posix-cpu-timers.c:1422 tick_sched_handle kernel/time/tick-sched.c:276 [inline] tick_nohz_handler+0x37c/0x500 kernel/time/tick-sched.c:297 __run_hrtimer kernel/time/hrtimer.c:1738 [inline] __hrtimer_run_queues+0x551/0xd30 kernel/time/hrtimer.c:1802 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1864 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5855 Code: 2b 00 74 08 4c 89 f7 e8 ca 40 8b 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000d38fc00 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92001a71f8c RCX: ffff88801f46d358 RDX: dffffc0000000000 RSI: ffffffff8c0aa400 RDI: ffffffff8c602960 RBP: ffffc9000d38fd58 R08: ffffffff942f987f R09: 1ffffffff285f30f R10: dffffc0000000000 R11: fffffbfff285f310 R12: 1ffff92001a71f88 R13: dffffc0000000000 R14: ffffc9000d38fc60 R15: 0000000000000246 __might_fault+0xc6/0x120 mm/memory.c:6770 rseq_get_rseq_cs kernel/rseq.c:248 [inline] rseq_ip_fixup kernel/rseq.c:368 [inline] __rseq_handle_notify_resume+0x120/0x14e0 kernel/rseq.c:416 rseq_handle_notify_resume include/linux/rseq.h:38 [inline] resume_user_mode_work include/linux/resume_user_mode.h:62 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x115/0x340 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd1319bf5e5 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 54 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f 55 ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffd8e71aa70 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: 0000000000000000 RBX: 00007fd131ba5fa0 RCX: 00007fd1319bf5e5 RDX: 00007ffd8e71aab0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007fd131ba7ba0 R08: 0000000000000000 R09: 7fffffffffffffff R10: 0000000000000000 R11: 0000000000000293 R12: 000000000001a94f R13: 00007fd131ba6080 R14: 0000000000000032 R15: ffffffffffffffff ---------------- Code disassembly (best guess): 0: 2b 00 sub (%rax),%eax 2: 74 08 je 0xc 4: 4c 89 f7 mov %r14,%rdi 7: e8 ca 40 8b 00 call 0x8b40d6 c: f6 44 24 61 02 testb $0x2,0x61(%rsp) 11: 0f 85 85 01 00 00 jne 0x19c 17: 41 f7 c7 00 02 00 00 test $0x200,%r15d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 40 0e 36 movq $0x45e0360e,0x40(%rsp) 28: e0 45 * 2a: 4b c7 44 25 00 00 00 movq $0x0,0x0(%r13,%r12,1) <-- trapping instruction 31: 00 00 33: 43 c7 44 25 09 00 00 movl $0x0,0x9(%r13,%r12,1) 3a: 00 00 3c: 43 rex.XB 3d: c7 .byte 0xc7 3e: 44 rex.R 3f: 25 .byte 0x25