general protection fault in write_special_inodes

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4ba8e26127c3 Linux 4.14.262
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14cd732fb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=51e11aabddb4cf62
dashboard link: https://syzkaller.appspot.com/bug?extid=7e05351c57d5699b69b6
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)

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+7e0535...@syzkaller.appspotmail.com

JFS: discard option not supported on device
JFS: discard option not supported on device
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
Modules linked in:
CPU: 1 PID: 10321 Comm: syz-executor.0 Not tainted 4.14.262-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff888057232600 task.stack: ffff88804d608000
RIP: 0010:write_special_inodes+0xa6/0x170 fs/jfs/jfs_logmgr.c:221
RSP: 0018:ffff88804d60fab8 EFLAGS: 00010206
RAX: 0000000000000006 RBX: ffff8880b013de80 RCX: ffffc90008615000
RDX: 000000000001301a RSI: ffffffff8168b0f5 RDI: 0000000000000030
RBP: dffffc0000000000 R08: ffffffff8b9dc158 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff8168b290
R13: 0000000000000000 R14: ffff88809d0ae940 R15: 0000000000000000
FS: 00007faac177b700(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2de30000 CR3: 00000000b0517000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
jfs_flush_journal.part.0+0x251/0x600 fs/jfs/jfs_logmgr.c:1595
jfs_flush_journal+0x23/0x30 fs/jfs/jfs_logmgr.c:1537
jfs_umount+0xbf/0x310 fs/jfs/jfs_umount.c:71
jfs_fill_super+0x7a5/0xab0 fs/jfs/super.c:633
mount_bdev+0x2b3/0x360 fs/super.c:1134
mount_fs+0x92/0x2a0 fs/super.c:1237
vfs_kern_mount.part.0+0x5b/0x470 fs/namespace.c:1046
vfs_kern_mount fs/namespace.c:1036 [inline]
do_new_mount fs/namespace.c:2572 [inline]
do_mount+0xe65/0x2a10 fs/namespace.c:2902
SYSC_mount fs/namespace.c:3118 [inline]
SyS_mount+0xa8/0x120 fs/namespace.c:3095
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7faac2e0751a
RSP: 002b:00007faac177af88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007faac2e0751a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007faac177afe0
RBP: 00007faac177b020 R08: 00007faac177b020 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007faac177afe0 R15: 0000000020000040
Code: 49 8b 7d 30 41 ff d4 48 8d 7b 28 48 89 f8 48 c1 e8 03 80 3c 28 00 0f 85 ab 00 00 00 4c 8b 6b 28 49 8d 7d 30 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 88 00 00 00 49 8b 7d 30 41 ff d4 48 8d bb b0
RIP: write_special_inodes+0xa6/0x170 fs/jfs/jfs_logmgr.c:221 RSP: ffff88804d60fab8
EXT4-fs (loop5): Unrecognized mount option "0x0000000000000096�" or missing value
---[ end trace dcbd8156de86bc35 ]---
ieee80211 phy5: hwaddr 02:00:00:00:05:00 registered
----------------
Code disassembly (best guess):
0: 49 8b 7d 30 mov 0x30(%r13),%rdi
4: 41 ff d4 callq *%r12
7: 48 8d 7b 28 lea 0x28(%rbx),%rdi
b: 48 89 f8 mov %rdi,%rax
e: 48 c1 e8 03 shr $0x3,%rax
12: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1)
16: 0f 85 ab 00 00 00 jne 0xc7
1c: 4c 8b 6b 28 mov 0x28(%rbx),%r13
20: 49 8d 7d 30 lea 0x30(%r13),%rdi
24: 48 89 f8 mov %rdi,%rax
27: 48 c1 e8 03 shr $0x3,%rax
* 2b: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) <-- trapping instruction
2f: 0f 85 88 00 00 00 jne 0xbd
35: 49 8b 7d 30 mov 0x30(%r13),%rdi
39: 41 ff d4 callq *%r12
3c: 48 rex.W
3d: 8d .byte 0x8d
3e: bb .byte 0xbb
3f: b0 .byte 0xb0


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[syzbot]

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