general protection fault, probably for non-canonical address 0xdffffc000000000b: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000058-0x000000000000005f] CPU: 0 PID: 10185 Comm: syz-executor.3 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__io_req_set_refcount fs/io_uring.c:1123 [inline] RIP: 0010:__io_prep_linked_timeout fs/io_uring.c:1319 [inline] RIP: 0010:io_prep_linked_timeout fs/io_uring.c:1327 [inline] RIP: 0010:__io_queue_sqe+0x1fb/0xcf0 fs/io_uring.c:6512 Code: 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 50 0a 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 65 70 49 8d 7c 24 58 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e a0 08 00 00 41 8b 44 24 58 a9 RSP: 0018:ffffc9000aaefd50 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 1ffff9200155dfb0 RCX: ffffffff81c74e8d RDX: 000000000000000b RSI: 0000000000000004 RDI: 0000000000000058 RBP: ffff88801b9e8280 R08: 0000000000000001 R09: ffff88801b9e82df R10: ffffed100373d05b R11: ffff8881441b26a0 R12: 0000000000000000 R13: ffff88801b9e82f0 R14: dffffc0000000000 R15: ffff88801b9e8310 FS: 00007f379013c700(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555579f14438 CR3: 00000000168a8000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: io_req_task_submit+0x93/0x110 fs/io_uring.c:2110 tctx_task_work+0x110/0x420 fs/io_uring.c:2034 task_work_run+0xc0/0x160 kernel/task_work.c:164 tracehook_notify_signal include/linux/tracehook.h:212 [inline] handle_signal_work kernel/entry/common.c:146 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x256/0x290 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:302 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665e9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f379013c188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000000200 RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000000000000 RSI: 00000000000045f5 RDI: 0000000000000003 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fff1cc41a4f R14: 00007f379013c300 R15: 0000000000022000 Modules linked in: ---[ end trace 014404aba8a8c3d0 ]--- RIP: 0010:__io_req_set_refcount fs/io_uring.c:1123 [inline] RIP: 0010:__io_prep_linked_timeout fs/io_uring.c:1319 [inline] RIP: 0010:io_prep_linked_timeout fs/io_uring.c:1327 [inline] RIP: 0010:__io_queue_sqe+0x1fb/0xcf0 fs/io_uring.c:6512 Code: 89 ea 48 c1 ea 03 80 3c 02 00 0f 85 50 0a 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b 65 70 49 8d 7c 24 58 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e a0 08 00 00 41 8b 44 24 58 a9 RSP: 0018:ffffc9000aaefd50 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 1ffff9200155dfb0 RCX: ffffffff81c74e8d RDX: 000000000000000b RSI: 0000000000000004 RDI: 0000000000000058 RBP: ffff88801b9e8280 R08: 0000000000000001 R09: ffff88801b9e82df R10: ffffed100373d05b R11: ffff8881441b26a0 R12: 0000000000000000 R13: ffff88801b9e82f0 R14: dffffc0000000000 R15: ffff88801b9e8310 FS: 00007f379013c700(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5d40ece000 CR3: 00000000168a8000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 89 ea mov %ebp,%edx 2: 48 c1 ea 03 shr $0x3,%rdx 6: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) a: 0f 85 50 0a 00 00 jne 0xa60 10: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 17: fc ff df 1a: 4c 8b 65 70 mov 0x70(%rbp),%r12 1e: 49 8d 7c 24 58 lea 0x58(%r12),%rdi 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx 2a: 0f b6 04 02 movzbl (%rdx,%rax,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 74 08 je 0x3a 32: 3c 03 cmp $0x3,%al 34: 0f 8e a0 08 00 00 jle 0x8da 3a: 41 8b 44 24 58 mov 0x58(%r12),%eax 3f: a9 .byte 0xa9