[xfs?] general protection fault in list_sort

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 933174ae28ba Merge tag 'spi-fix-v6.4-rc3' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11dbf7d9280000
kernel config: https://syzkaller.appspot.com/x/.config?x=f389ffdf4e9ba3f0
dashboard link: https://syzkaller.appspot.com/bug?extid=4895a13d9f71639fb3e9
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: i386
CC: [djw...@kernel.org linux-...@vger.kernel.org linux-...@vger.kernel.org linu...@vger.kernel.org]

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

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-933174ae.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/d85feaa2e417/vmlinux-933174ae.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3edcd6a1974c/bzImage-933174ae.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4895a1...@syzkaller.appspotmail.com

XFS (loop1): Mounting V4 Filesystem 5e6273b8-2167-42bb-911b-418aa14a1261
XFS (loop1): totally zeroed log
XFS (loop1): Ending clean mount
XFS (loop1): Quotacheck needed: Please wait.
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 1 PID: 7503 Comm: syz-executor.1 Not tainted 6.4.0-rc3-syzkaller-00032-g933174ae28ba #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:list_sort+0x2dd/0x970 lib/list_sort.c:232
Code: e8 03 42 80 3c 38 00 0f 85 08 06 00 00 48 8b 44 24 10 48 89 28 e8 13 c9 73 fd 4c 8d 63 08 48 8b 6c 24 70 4c 89 e0 48 c1 e8 03 <42> 80 3c 38 00 0f 85 57 06 00 00 48 89 d8 48 89 6b 08 48 c1 e8 03
RSP: 0018:ffffc9000df7f518 EFLAGS: 00010202
RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffc90003949000
RDX: 0000000000040000 RSI: ffffffff841079bd RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000008
R13: 1ffff92001befee8 R14: 0000000000000000 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff88802c700000(0063) knlGS:00000000f7f1ab40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 00000000f727fc30 CR3: 0000000048ed4000 CR4: 0000000000350ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
xfs_buf_delwri_submit_buffers+0x97/0x990 fs/xfs/xfs_buf.c:2151
xfs_buf_delwri_pushbuf+0x261/0x4a0 fs/xfs/xfs_buf.c:2304
xfs_qm_flush_one+0x351/0x3b0 fs/xfs/xfs_qm.c:1253
xfs_qm_dquot_walk.isra.0+0x1be/0x3f0 fs/xfs/xfs_qm.c:87
xfs_qm_quotacheck+0x3c0/0x940 fs/xfs/xfs_qm.c:1338
xfs_qm_mount_quotas+0x125/0x690 fs/xfs/xfs_qm.c:1457
xfs_mountfs+0x1e07/0x1f60 fs/xfs/xfs_mount.c:959
xfs_fs_fill_super+0x145b/0x1f80 fs/xfs/xfs_super.c:1693
get_tree_bdev+0x44a/0x770 fs/super.c:1303
vfs_get_tree+0x8d/0x350 fs/super.c:1510
do_new_mount fs/namespace.c:3039 [inline]
path_mount+0x134b/0x1e40 fs/namespace.c:3369
do_mount fs/namespace.c:3382 [inline]
__do_sys_mount fs/namespace.c:3591 [inline]
__se_sys_mount fs/namespace.c:3568 [inline]
__ia32_sys_mount+0x282/0x300 fs/namespace.c:3568
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
entry_SYSENTER_compat_after_hwframe+0x70/0x82
RIP: 0023:0xf7f1f579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f1a410 EFLAGS: 00000296 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00000000f7f1a480 RCX: 000000002000bb40
RDX: 000000002000bb00 RSI: 0000000002000000 RDI: 00000000f7f1a4c0
RBP: 00000000f7f1a4c0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:list_sort+0x2dd/0x970 lib/list_sort.c:232
Code: e8 03 42 80 3c 38 00 0f 85 08 06 00 00 48 8b 44 24 10 48 89 28 e8 13 c9 73 fd 4c 8d 63 08 48 8b 6c 24 70 4c 89 e0 48 c1 e8 03 <42> 80 3c 38 00 0f 85 57 06 00 00 48 89 d8 48 89 6b 08 48 c1 e8 03
RSP: 0018:ffffc9000df7f518 EFLAGS: 00010202

RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffc90003949000
RDX: 0000000000040000 RSI: ffffffff841079bd RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000008
----------------
Code disassembly (best guess):
0: e8 03 42 80 3c callq 0x3c804208
5: 38 00 cmp %al,(%rax)
7: 0f 85 08 06 00 00 jne 0x615
d: 48 8b 44 24 10 mov 0x10(%rsp),%rax
12: 48 89 28 mov %rbp,(%rax)
15: e8 13 c9 73 fd callq 0xfd73c92d
1a: 4c 8d 63 08 lea 0x8(%rbx),%r12
1e: 48 8b 6c 24 70 mov 0x70(%rsp),%rbp
23: 4c 89 e0 mov %r12,%rax
26: 48 c1 e8 03 shr $0x3,%rax
* 2a: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction
2f: 0f 85 57 06 00 00 jne 0x68c
35: 48 89 d8 mov %rbx,%rax
38: 48 89 6b 08 mov %rbp,0x8(%rbx)
3c: 48 c1 e8 03 shr $0x3,%rax


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.