[moderation] [fs?] WARNING in show_mark_fhandle

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 66cc544fd75c Merge tag 'dmaengine-fix-6.10' of git://git.k..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12e73b9c980000
kernel config: https://syzkaller.appspot.com/x/.config?x=d24262d81a9225c6
dashboard link: https://syzkaller.appspot.com/bug?extid=d2934e73a6b0e52ac572
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386
CC: [amir...@gmail.com ja...@suse.cz linux-...@vger.kernel.org linux-...@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-66cc544f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e892c6950dc1/vmlinux-66cc544f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9ffc13e76cfc/bzImage-66cc544f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d2934e...@syzkaller.appspotmail.com

------------[ cut here ]------------
Can't encode file handler for inotify: 255
WARNING: CPU: 0 PID: 5369 at fs/notify/fdinfo.c:51 show_mark_fhandle+0x204/0x220 fs/notify/fdinfo.c:51
Modules linked in:
CPU: 0 PID: 5369 Comm: syz-executor.1 Not tainted 6.10.0-rc4-syzkaller-00164-g66cc544fd75c #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:show_mark_fhandle+0x204/0x220 fs/notify/fdinfo.c:51
Code: 31 ff 89 ee e8 0d a5 7e ff 40 84 ed 75 92 e8 63 aa 7e ff c6 05 e4 6e bc 0d 01 90 48 c7 c7 80 63 3e 8b 89 de e8 4d 2b 41 ff 90 <0f> 0b 90 90 e9 6d ff ff ff e8 2e d7 db ff e9 3b ff ff ff e8 04 13
RSP: 0018:ffffc900037878c0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 00000000000000ff RCX: ffffc9002319a000
RDX: 0000000000040000 RSI: ffffffff81511296 RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000002 R12: ffff888020e7ade0
R13: dffffc0000000000 R14: 1ffff920006f0f18 R15: 0000000000000010
FS: 0000000000000000(0000) GS:ffff88802c000000(0063) knlGS:00000000f5ef0b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 000000003352d000 CR3: 0000000012b3a000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
inotify_fdinfo+0x223/0x2d0 fs/notify/fdinfo.c:86
show_fdinfo.isra.0+0x1e4/0x380 fs/notify/fdinfo.c:34
seq_show+0x574/0x910 fs/proc/fd.c:68
seq_read_iter+0x4fa/0x12c0 fs/seq_file.c:230
seq_read+0x390/0x4d0 fs/seq_file.c:162
vfs_read+0x1d4/0xbd0 fs/read_write.c:474
ksys_pread64+0x176/0x1a0 fs/read_write.c:671
do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
__do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf72fe579
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:00000000f5ef05ac EFLAGS: 00000292 ORIG_RAX: 00000000000000b4
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 0000000020000080
RDX: 00000000000000ed RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
----------------
Code disassembly (best guess), 2 bytes skipped:
0: 10 06 adc %al,(%rsi)
2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi
6: 10 07 adc %al,(%rdi)
8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi
c: 10 08 adc %cl,(%rax)
e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi
1e: 00 51 52 add %dl,0x52(%rcx)
21: 55 push %rbp
22: 89 e5 mov %esp,%ebp
24: 0f 34 sysenter
26: cd 80 int $0x80
* 28: 5d pop %rbp <-- trapping instruction
29: 5a pop %rdx
2a: 59 pop %rcx
2b: c3 ret
2c: 90 nop
2d: 90 nop
2e: 90 nop
2f: 90 nop
30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi


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