general protection fault, probably for non-canonical address 0xdffffc000000008b: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000458-0x000000000000045f] CPU: 0 PID: 10497 Comm: syz-executor.0 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:941 [inline] RIP: 0010:__mutex_lock+0xe7/0x10a0 kernel/locking/mutex.c:1104 Code: d0 7c 08 84 d2 0f 85 aa 0c 00 00 8b 15 02 f1 f5 06 85 d2 75 29 48 8d 7d 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 c3 0e 00 00 48 3b 6d 60 0f 85 2a 0a 00 00 bf 01 RSP: 0018:ffffc9000b0cfd48 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 000000000000008b RSI: 0000000000000000 RDI: 000000000000045f RBP: 00000000000003ff R08: ffffffff846dc3d7 R09: ffffffff8c486763 R10: fffffbfff1890cec R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffffffffffffff R15: 00000000000003ff FS: 00007f70c9bbb700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055df956b6c58 CR3: 000000003d551000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: loop_control_remove drivers/block/loop.c:2477 [inline] loop_control_ioctl+0x237/0x410 drivers/block/loop.c:2525 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 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:00007f70c9bbb188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665e9 RDX: 0000000000000001 RSI: 0000000000004c81 RDI: 0000000000000005 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffcbf677caf R14: 00007f70c9bbb300 R15: 0000000000022000 Modules linked in: ---[ end trace a4befb127fcfc4b4 ]--- RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:941 [inline] RIP: 0010:__mutex_lock+0xe7/0x10a0 kernel/locking/mutex.c:1104 Code: d0 7c 08 84 d2 0f 85 aa 0c 00 00 8b 15 02 f1 f5 06 85 d2 75 29 48 8d 7d 60 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 c3 0e 00 00 48 3b 6d 60 0f 85 2a 0a 00 00 bf 01 RSP: 0018:ffffc9000b0cfd48 EFLAGS: 00010207 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 000000000000008b RSI: 0000000000000000 RDI: 000000000000045f RBP: 00000000000003ff R08: ffffffff846dc3d7 R09: ffffffff8c486763 R10: fffffbfff1890cec R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffffffffffffffff R15: 00000000000003ff FS: 00007f70c9bbb700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbca3ac9fe8 CR3: 000000003d551000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: d0 7c 08 84 sarb -0x7c(%rax,%rcx,1) 4: d2 0f rorb %cl,(%rdi) 6: 85 aa 0c 00 00 8b test %ebp,-0x74fffff4(%rdx) c: 15 02 f1 f5 06 adc $0x6f5f102,%eax 11: 85 d2 test %edx,%edx 13: 75 29 jne 0x3e 15: 48 8d 7d 60 lea 0x60(%rbp),%rdi 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 fa mov %rdi,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 c3 0e 00 00 jne 0xef7 34: 48 3b 6d 60 cmp 0x60(%rbp),%rbp 38: 0f 85 2a 0a 00 00 jne 0xa68 3e: bf .byte 0xbf 3f: 01 .byte 0x1