WARNING in cramfs_kill_sb (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b8f3be299d51 Linux 4.14.282
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=135de957f00000
kernel config: https://syzkaller.appspot.com/x/.config?x=6f19bc3398ea47b8
dashboard link: https://syzkaller.appspot.com/bug?extid=ea48171814995c17cc60
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+ea4817...@syzkaller.appspotmail.com

ext4_alloc_inode+0x1a/0x640 fs/ext4/super.c:1013
alloc_inode+0x5d/0x170 fs/inode.c:210
new_inode_pseudo fs/inode.c:899 [inline]
new_inode+0x1d/0xf0 fs/inode.c:928
__ext4_new_inode+0x360/0x4eb0 fs/ext4/ialloc.c:839
------------[ cut here ]------------
WARNING: CPU: 0 PID: 17340 at fs/super.c:1163 kill_block_super+0xbe/0xe0 fs/super.c:1163
Kernel panic - not syncing: panic_on_warn set ...

ext4_mkdir+0x2e4/0xbd0 fs/ext4/namei.c:2674
vfs_mkdir+0x463/0x6e0 fs/namei.c:3849
SYSC_mkdirat fs/namei.c:3872 [inline]
SyS_mkdirat+0x1fd/0x270 fs/namei.c:3856
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fe531ea3217
RSP: 002b:00007fe530818f88 EFLAGS: 00000213 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007fe531ea3217
RDX: 00000000000001ff RSI: 0000000020000100 RDI: 00000000ffffff9c
RBP: 00007fe5308191d0 R08: 0000000000000000 R09: 00007fe5308191d0
R10: 0000000000000000 R11: 0000000000000213 R12: 0000000020000000
R13: 0000000020000100 R14: 00007fe530818fe0 R15: 0000000020010200
CPU: 0 PID: 17340 Comm: syz-executor.2 Not tainted 4.14.282-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x1b2/0x281 lib/dump_stack.c:58
panic+0x1f9/0x42d kernel/panic.c:183
__warn.cold+0x20/0x44 kernel/panic.c:547
report_bug+0x208/0x250 lib/bug.c:183
fixup_bug arch/x86/kernel/traps.c:177 [inline]
fixup_bug arch/x86/kernel/traps.c:172 [inline]
do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:964
RIP: 0010:kill_block_super+0xbe/0xe0 fs/super.c:1163
RSP: 0018:ffff88805379fbb0 EFLAGS: 00010246
RAX: 0000000000040000 RBX: 0000000000000000 RCX: ffffc90007ded000
RDX: 0000000000040000 RSI: ffffffff818760de RDI: ffff88809071b6b0
RBP: ffff88804c52cdc0 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: ffff88804e552080 R12: ffff88809071b200
R13: ffffffff890a3150 R14: ffffffff88f45500 R15: dffffc0000000000
cramfs_kill_sb+0x38/0x50 fs/cramfs/inode.c:247
deactivate_locked_super+0x6c/0xd0 fs/super.c:319
sget_userns+0x9c4/0xc10 fs/super.c:537
sget+0xd1/0x110 fs/super.c:572
mount_bdev+0xcd/0x360 fs/super.c:1107
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+0xe65/0x2a30 fs/namespace.c:2905
SYSC_mount fs/namespace.c:3121 [inline]
SyS_mount+0xa8/0x120 fs/namespace.c:3098
do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f490a1e163a
RSP: 002b:00007f4908b54f88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 00007f490a1e163a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f4908b54fe0
RBP: 00007f4908b55020 R08: 00007f4908b55020 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f4908b54fe0 R15: 0000000020010200
Kernel Offset: disabled
Rebooting in 86400 seconds..


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[syzbot]

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