ksys_ioctl fs/ioctl.c:742 [inline]
__do_sys_ioctl fs/ioctl.c:749 [inline]
__se_sys_ioctl fs/ioctl.c:747 [inline]
__x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
---[ end trace 0e0bec924c313ccf ]---
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 308 Comm: syz-executor443 Tainted: G W 5.4.219-syzkaller-00012-ga8aad8851131 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:strlen+0x2a/0x60 lib/string.c:552
Code: 41 57 41 56 41 54 53 49 89 fe 48 c7 c0 ff ff ff ff 49 bf 00 00 00 00 00 fc ff df 48 89 fb 66 90 49 89 c4 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 12 48 ff c3 49 8d 44 24 01 43 80 7c 26 01
RSP: 0018:ffff8881e086f9c0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8881dd835e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff81b9a329 R09: ffffed103c10df3d
R10: ffffed103c10df3d R11: 1ffff1103c10df3c R12: ffffffffffffffff
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS: 000055555750f300(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f57c5fed130 CR3: 00000001de2a9000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
kernfs_name_hash+0x1e/0x220 fs/kernfs/dir.c:310
kernfs_find_ns+0x6b/0x260 fs/kernfs/dir.c:855
kernfs_remove_by_name_ns+0x32/0x90 fs/kernfs/dir.c:1517
del_gendisk+0x98a/0xbf0 block/genhd.c:833
loop_remove+0x42/0xa0 drivers/block/loop.c:2194
loop_control_ioctl+0x67f/0x740 drivers/block/loop.c:2293
do_vfs_ioctl+0x744/0x1730 fs/ioctl.c:47
ksys_ioctl fs/ioctl.c:742 [inline]
__do_sys_ioctl fs/ioctl.c:749 [inline]
__se_sys_ioctl fs/ioctl.c:747 [inline]
__x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
do_syscall_64+0xcb/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x5c/0xc1
Modules linked in:
---[ end trace 0e0bec924c313cd0 ]---
RIP: 0010:strlen+0x2a/0x60 lib/string.c:552
Code: 41 57 41 56 41 54 53 49 89 fe 48 c7 c0 ff ff ff ff 49 bf 00 00 00 00 00 fc ff df 48 89 fb 66 90 49 89 c4 48 89 d8 48 c1 e8 03 <42> 0f b6 04 38 84 c0 75 12 48 ff c3 49 8d 44 24 01 43 80 7c 26 01
RSP: 0018:ffff8881e086f9c0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8881dd835e80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff81b9a329 R09: ffffed103c10df3d
R10: ffffed103c10df3d R11: 1ffff1103c10df3c R12: ffffffffffffffff
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS: 000055555750f300(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f57c5fed130 CR3: 00000001de2a9000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 41 57 push %r15
2: 41 56 push %r14
4: 41 54 push %r12
6: 53 push %rbx
7: 49 89 fe mov %rdi,%r14
a: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax
11: 49 bf 00 00 00 00 00 movabs $0xdffffc0000000000,%r15
18: fc ff df
1b: 48 89 fb mov %rdi,%rbx
1e: 66 90 xchg %ax,%ax
20: 49 89 c4 mov %rax,%r12
23: 48 89 d8 mov %rbx,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 0f b6 04 38 movzbl (%rax,%r15,1),%eax <-- trapping instruction
2f: 84 c0 test %al,%al
31: 75 12 jne 0x45
33: 48 ff c3 inc %rbx
36: 49 8d 44 24 01 lea 0x1(%r12),%rax
3b: 43 rex.XB
3c: 80 .byte 0x80
3d: 7c 26 jl 0x65
3f: 01 .byte 0x1