general protection fault in del_gendisk

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: a8aad8851131 ANDROID: GKI: enable mulitcolor-led
git tree: android12-5.4
console output: https://syzkaller.appspot.com/x/log.txt?x=14e01f64480000
kernel config: https://syzkaller.appspot.com/x/.config?x=b4f7fdc1fca3154e
dashboard link: https://syzkaller.appspot.com/bug?extid=6bbe34fc87953b72ac13
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/71fa3d1afcd2/disk-a8aad885.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6d25e2985873/vmlinux-a8aad885.xz
kernel image: https://storage.googleapis.com/syzbot-assets/97866ff1e151/bzImage-a8aad885.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6bbe34...@syzkaller.appspotmail.com

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 8b0af1f7665720ad ]---
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: 1 PID: 24672 Comm: syz-executor.3 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:kill_device drivers/base/core.c:3022 [inline]
RIP: 0010:device_del+0xe7/0x1000 drivers/base/core.c:3049
Code: df e8 4d 6f 04 ff 4c 89 7c 24 18 41 bf c8 00 00 00 48 89 5c 24 08 4c 03 3b 4d 89 fc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 8a 04 04 84 c0 0f 85 88 0e 00 00 41 0f b6 1f 89 de 83 e6 01 31
RSP: 0018:ffff8881ef54f9a0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881e70e40d8 RCX: 1ffff1103ce1c81b
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881ef54f920
RBP: ffff8881ef54fa70 R08: dffffc0000000000 R09: ffffed103dea9f25
R10: ffffed103dea9f25 R11: 1ffff1103dea9f24 R12: 0000000000000019
R13: ffff8881e70e4070 R14: ffff8881e70e4110 R15: 00000000000000c8
FS: 00007f1157c99700(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0200d9ddc0 CR3: 00000001e54e2000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
del_gendisk+0x99c/0xbf0 block/genhd.c:835
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 8b0af1f7665720ae ]---
RIP: 0010:kill_device drivers/base/core.c:3022 [inline]
RIP: 0010:device_del+0xe7/0x1000 drivers/base/core.c:3049
Code: df e8 4d 6f 04 ff 4c 89 7c 24 18 41 bf c8 00 00 00 48 89 5c 24 08 4c 03 3b 4d 89 fc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 8a 04 04 84 c0 0f 85 88 0e 00 00 41 0f b6 1f 89 de 83 e6 01 31
RSP: 0018:ffff8881ef54f9a0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881e70e40d8 RCX: 1ffff1103ce1c81b
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881ef54f920
RBP: ffff8881ef54fa70 R08: dffffc0000000000 R09: ffffed103dea9f25
R10: ffffed103dea9f25 R11: 1ffff1103dea9f24 R12: 0000000000000019
R13: ffff8881e70e4070 R14: ffff8881e70e4110 R15: 00000000000000c8
FS: 00007f1157c99700(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff40062a000 CR3: 00000001e54e2000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: df e8 fucomip %st(0),%st
2: 4d 6f rex.WRB outsl %ds:(%rsi),(%dx)
4: 04 ff add $0xff,%al
6: 4c 89 7c 24 18 mov %r15,0x18(%rsp)
b: 41 bf c8 00 00 00 mov $0xc8,%r15d
11: 48 89 5c 24 08 mov %rbx,0x8(%rsp)
16: 4c 03 3b add (%rbx),%r15
19: 4d 89 fc mov %r15,%r12
1c: 49 c1 ec 03 shr $0x3,%r12
20: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
27: fc ff df
* 2a: 41 8a 04 04 mov (%r12,%rax,1),%al <-- trapping instruction
2e: 84 c0 test %al,%al
30: 0f 85 88 0e 00 00 jne 0xebe
36: 41 0f b6 1f movzbl (%r15),%ebx
3a: 89 de mov %ebx,%esi
3c: 83 e6 01 and $0x1,%esi
3f: 31 .byte 0x31


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: a8aad8851131 ANDROID: GKI: enable mulitcolor-led
git tree: android12-5.4

console+strace: https://syzkaller.appspot.com/x/log.txt?x=1754b288480000

kernel config: https://syzkaller.appspot.com/x/.config?x=b4f7fdc1fca3154e
dashboard link: https://syzkaller.appspot.com/bug?extid=6bbe34fc87953b72ac13
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13986488480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1283dc40480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/71fa3d1afcd2/disk-a8aad885.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6d25e2985873/vmlinux-a8aad885.xz
kernel image: https://storage.googleapis.com/syzbot-assets/97866ff1e151/bzImage-a8aad885.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6bbe34...@syzkaller.appspotmail.com

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 7c922977edc3bb57 ]---

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: 1 PID: 308 Comm: syz-executor313 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:kill_device drivers/base/core.c:3022 [inline]
RIP: 0010:device_del+0xe7/0x1000 drivers/base/core.c:3049
Code: df e8 4d 6f 04 ff 4c 89 7c 24 18 41 bf c8 00 00 00 48 89 5c 24 08 4c 03 3b 4d 89 fc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 8a 04 04 84 c0 0f 85 88 0e 00 00 41 0f b6 1f 89 de 83 e6 01 31

RSP: 0018:ffff8881ddaf79a0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881dda110d8 RCX: 1ffff1103bb4221b
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881ddaf7920
RBP: ffff8881ddaf7a70 R08: dffffc0000000000 R09: ffffed103bb5ef25
R10: ffffed103bb5ef25 R11: 1ffff1103bb5ef24 R12: 0000000000000019
R13: ffff8881dda11070 R14: ffff8881dda11110 R15: 00000000000000c8
FS: 0000555556de2300(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f26cd705130 CR3: 00000001e2b18000 CR4: 00000000003406e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
del_gendisk+0x99c/0xbf0 block/genhd.c:835
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 7c922977edc3bb58 ]---

RIP: 0010:kill_device drivers/base/core.c:3022 [inline]
RIP: 0010:device_del+0xe7/0x1000 drivers/base/core.c:3049
Code: df e8 4d 6f 04 ff 4c 89 7c 24 18 41 bf c8 00 00 00 48 89 5c 24 08 4c 03 3b 4d 89 fc 49 c1 ec 03 48 b8 00 00 00 00 00 fc ff df <41> 8a 04 04 84 c0 0f 85 88 0e 00 00 41 0f b6 1f 89 de 83 e6 01 31

RSP: 0018:ffff8881ddaf79a0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881dda110d8 RCX: 1ffff1103bb4221b
RDX: 0000000000000001 RSI: 0000000000000008 RDI: ffff8881ddaf7920
RBP: ffff8881ddaf7a70 R08: dffffc0000000000 R09: ffffed103bb5ef25
R10: ffffed103bb5ef25 R11: 1ffff1103bb5ef24 R12: 0000000000000019
R13: ffff8881dda11070 R14: ffff8881dda11110 R15: 00000000000000c8
FS: 0000555556de2300(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f26cd705130 CR3: 00000001e2b18000 CR4: 00000000003406e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400