[syzbot] general protection fault in do_xmote

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c3e0e1e23c70 Merge tag 'irq_urgent_for_v6.0' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11664a70880000
kernel config: https://syzkaller.appspot.com/x/.config?x=a1992c90769e07
dashboard link: https://syzkaller.appspot.com/bug?extid=ececff266234ba40fe13
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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

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

general protection fault, probably for non-canonical address 0xdffffc0000000097: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000004b8-0x00000000000004bf]
CPU: 2 PID: 70 Comm: kworker/2:1H Not tainted 6.0.0-rc7-syzkaller-00081-gc3e0e1e23c70 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: glock_workqueue glock_work_func
RIP: 0010:is_system_glock fs/gfs2/glock.c:720 [inline]
RIP: 0010:do_xmote+0x492/0xc40 fs/gfs2/glock.c:828
Code: 03 80 3c 02 00 0f 85 2f 07 00 00 4d 8b ad 18 07 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bd b8 04 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 ed 06 00 00 49 3b ad b8 04 00 00 0f 84 77 05 00
RSP: 0018:ffffc90000aa7c50 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888027624000 RCX: 0000000000000000
RDX: 0000000000000097 RSI: ffffffff8381e370 RDI: 00000000000004b8
RBP: ffff888074ceea90 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888074ceeaf8 R15: ffff888074ceeab0
FS: 0000000000000000(0000) GS:ffff88802ca00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000990140 CR3: 0000000076461000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
run_queue+0x3cf/0x660 fs/gfs2/glock.c:893
glock_work_func+0xbe/0x3a0 fs/gfs2/glock.c:1059
process_one_work+0x991/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:is_system_glock fs/gfs2/glock.c:720 [inline]
RIP: 0010:do_xmote+0x492/0xc40 fs/gfs2/glock.c:828
Code: 03 80 3c 02 00 0f 85 2f 07 00 00 4d 8b ad 18 07 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bd b8 04 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 ed 06 00 00 49 3b ad b8 04 00 00 0f 84 77 05 00
RSP: 0018:ffffc90000aa7c50 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff888027624000 RCX: 0000000000000000
RDX: 0000000000000097 RSI: ffffffff8381e370 RDI: 00000000000004b8
RBP: ffff888074ceea90 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: ffff888074ceeaf8 R15: ffff888074ceeab0
FS: 0000000000000000(0000) GS:ffff88802ca00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000990140 CR3: 0000000076461000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess), 1 bytes skipped:
0: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1)
4: 0f 85 2f 07 00 00 jne 0x739
a: 4d 8b ad 18 07 00 00 mov 0x718(%r13),%r13
11: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
18: fc ff df
1b: 49 8d bd b8 04 00 00 lea 0x4b8(%r13),%rdi
22: 48 89 fa mov %rdi,%rdx
25: 48 c1 ea 03 shr $0x3,%rdx
* 29: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction
2d: 0f 85 ed 06 00 00 jne 0x720
33: 49 3b ad b8 04 00 00 cmp 0x4b8(%r13),%rbp
3a: 0f .byte 0xf
3b: 84 77 05 test %dh,0x5(%rdi)


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 764822972d64 Merge tag 'nfsd-6.2' of git://git.kernel.org/..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1428fb0b880000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c59170b68d26a55
dashboard link: https://syzkaller.appspot.com/bug?extid=ececff266234ba40fe13
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=14ce69c0480000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1016950b880000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/0c840c19749d/disk-76482297.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bdfd51618ae0/vmlinux-76482297.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fef17b5d4d6d/bzImage-76482297.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/a114b1cb5db6/mount_0.gz

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

general protection fault, probably for non-canonical address 0xdffffc0000000097: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000004b8-0x00000000000004bf]

CPU: 1 PID: 1273 Comm: kworker/1:1H Not tainted 6.1.0-syzkaller-03225-g764822972d64 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: glock_workqueue glock_work_func
RIP: 0010:is_system_glock fs/gfs2/glock.c:725 [inline]
RIP: 0010:do_xmote+0xdde/0x13d0 fs/gfs2/glock.c:835
Code: 00 48 03 5d 00 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 91 e1 27 fe bd b8 04 00 00 48 03 2b 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 73 e1 27 fe 4c 8b 64 24 08 4c 39
RSP: 0018:ffffc900061a7b70 EFLAGS: 00010202
RAX: 0000000000000097 RBX: ffff888021dd8718 RCX: ffff888021c93a80
RDX: 0000000000000000 RSI: 0000000000004000 RDI: 0000000000000000
RBP: 00000000000004b8 R08: ffffffff83b7d986 R09: ffffed10043bb016
R10: ffffed10043bb016 R11: 1ffff110043bb015 R12: ffff888075bf0548
R13: 0000000000000818 R14: dffffc0000000000 R15: ffff888021dd8000
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000

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

CR2: 0000000020002080 CR3: 000000007a61b000 CR4: 00000000003506e0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>

glock_work_func+0x2c2/0x450 fs/gfs2/glock.c:1082
process_one_work+0x877/0xdb0 kernel/workqueue.c:2289
worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
kthread+0x266/0x300 kernel/kthread.c:376

ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---

RIP: 0010:is_system_glock fs/gfs2/glock.c:725 [inline]
RIP: 0010:do_xmote+0xdde/0x13d0 fs/gfs2/glock.c:835
Code: 00 48 03 5d 00 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 91 e1 27 fe bd b8 04 00 00 48 03 2b 48 89 e8 48 c1 e8 03 <42> 80 3c 30 00 74 08 48 89 ef e8 73 e1 27 fe 4c 8b 64 24 08 4c 39
RSP: 0018:ffffc900061a7b70 EFLAGS: 00010202
RAX: 0000000000000097 RBX: ffff888021dd8718 RCX: ffff888021c93a80
RDX: 0000000000000000 RSI: 0000000000004000 RDI: 0000000000000000
RBP: 00000000000004b8 R08: ffffffff83b7d986 R09: ffffed10043bb016
R10: ffffed10043bb016 R11: 1ffff110043bb015 R12: ffff888075bf0548
R13: 0000000000000818 R14: dffffc0000000000 R15: ffff888021dd8000
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000

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

CR2: 0000000020002080 CR3: 000000007e6e4000 CR4: 00000000003506e0

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

Code disassembly (best guess):
0: 00 48 03 add %cl,0x3(%rax)
3: 5d pop %rbp
4: 00 48 89 add %cl,-0x77(%rax)
7: d8 48 c1 fmuls -0x3f(%rax)
a: e8 03 42 80 3c callq 0x3c804212
f: 30 00 xor %al,(%rax)
11: 74 08 je 0x1b
13: 48 89 df mov %rbx,%rdi
16: e8 91 e1 27 fe callq 0xfe27e1ac
1b: bd b8 04 00 00 mov $0x4b8,%ebp
20: 48 03 2b add (%rbx),%rbp
23: 48 89 e8 mov %rbp,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 30 00 cmpb $0x0,(%rax,%r14,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 ef mov %rbp,%rdi
34: e8 73 e1 27 fe callq 0xfe27e1ac
39: 4c 8b 64 24 08 mov 0x8(%rsp),%r12
3e: 4c rex.WR
3f: 39 .byte 0x39

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.