Re: [syzbot] possible deadlock in mnt_want_write_file

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in do_journal_begin_r

REISERFS (device loop0): journal params: device loop0, size 512, journal first block 18, max trans len 256, max batch 225, max commit age 30, max trans age 30
REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using tea hash to sort names
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
------------[ cut here ]------------
kernel BUG at fs/reiserfs/journal.c:3039!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 5794 Comm: syz-executor.0 Not tainted 6.1.0-rc6-syzkaller-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
RIP: 0010:do_journal_begin_r+0x105b/0x1070 fs/reiserfs/journal.c:3039
Code: ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 22 ff ff ff 48 89 df e8 a6 eb b2 ff e9 15 ff ff ff e8 bc d3 5e ff 0f 0b e8 b5 d3 5e ff <0f> 0b e8 2e 6f 6a 08 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 55
RSP: 0018:ffffc900095cf5e0 EFLAGS: 00010293
RAX: ffffffff822bc4bb RBX: 000000001100e5be RCX: ffff88807d299d40
RDX: 0000000000000000 RSI: 000000001100e5be RDI: 0000000000000100
RBP: ffffc900095cf788 R08: ffffffff822bb592 R09: fffffbfff1d2f2de
R10: fffffbfff1d2f2de R11: 1ffffffff1d2f2dd R12: ffff88807a6c6678
R13: ffffc9000ac11214 R14: dffffc0000000000 R15: 0000000000000100
FS:  00007fd0ac76a700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0abba8000 CR3: 000000007980d000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 journal_begin+0x14b/0x350 fs/reiserfs/journal.c:3255
 reiserfs_create+0x2c3/0x660 fs/reiserfs/namei.c:661
 lookup_open fs/namei.c:3413 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0x12d0/0x2df0 fs/namei.c:3710
 do_filp_open+0x264/0x4f0 fs/namei.c:3740
 do_sys_openat2+0x124/0x4e0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_creat fs/open.c:1402 [inline]
 __se_sys_creat fs/open.c:1396 [inline]
 __x64_sys_creat+0x11f/0x160 fs/open.c:1396
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fd0aba8c189
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd0ac76a168 EFLAGS: 00000246 ORIG_RAX: 0000000000000055
RAX: ffffffffffffffda RBX: 00007fd0abbabf80 RCX: 00007fd0aba8c189
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00007fd0abae7b01 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffeb4434c9f R14: 00007fd0ac76a300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:do_journal_begin_r+0x105b/0x1070 fs/reiserfs/journal.c:3039
Code: ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 22 ff ff ff 48 89 df e8 a6 eb b2 ff e9 15 ff ff ff e8 bc d3 5e ff 0f 0b e8 b5 d3 5e ff <0f> 0b e8 2e 6f 6a 08 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 55
RSP: 0018:ffffc900095cf5e0 EFLAGS: 00010293
RAX: ffffffff822bc4bb RBX: 000000001100e5be RCX: ffff88807d299d40
RDX: 0000000000000000 RSI: 000000001100e5be RDI: 0000000000000100
RBP: ffffc900095cf788 R08: ffffffff822bb592 R09: fffffbfff1d2f2de
R10: fffffbfff1d2f2de R11: 1ffffffff1d2f2dd R12: ffff88807a6c6678
R13: ffffc9000ac11214 R14: dffffc0000000000 R15: 0000000000000100
FS:  00007fd0ac76a700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd0abba8000 CR3: 000000007980d000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit:         eb708140 Linux 6.1-rc6
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=14428075880000
kernel config:  https://syzkaller.appspot.com/x/.config?x=8cdf448d3b35234
dashboard link: https://syzkaller.appspot.com/bug?extid=1047e42179f502f2b0a2
compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
patch:          https://syzkaller.appspot.com/x/patch.diff?x=153b4afd880000