WARNING in ext4_group_desc_csum

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 10c44c01 f2fs: fix build error on android tracepoints
git tree: android-4.9
console output: https://syzkaller.appspot.com/x/log.txt?x=15bd4622600000
kernel config: https://syzkaller.appspot.com/x/.config?x=5944ab99bb3d7b7c
dashboard link: https://syzkaller.appspot.com/bug?extid=99bcc5f51651697b2020
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+99bcc5...@syzkaller.appspotmail.com

EXT4-fs (loop4): mount failed
EXT4-fs (loop4): ext4_check_descriptors: Block bitmap for group 0 overlaps
superblock
EXT4-fs (loop4): ext4_check_descriptors: Inode bitmap for group 0 overlaps
superblock
EXT4-fs (loop4): ext4_check_descriptors: Inode table for group 0 overlaps
superblock
------------[ cut here ]------------
WARNING: CPU: 0 PID: 16654 at fs/ext4/ext4.h:2721 ext4_has_metadata_csum
fs/ext4/ext4.h:2721 [inline]
WARNING: CPU: 0 PID: 16654 at fs/ext4/ext4.h:2721
ext4_group_desc_csum.isra.0+0x537/0xa40 fs/ext4/super.c:2190
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 16654 Comm: syz-executor.4 Not tainted 4.9.189+ #2
ffff8801b016f798 ffffffff81b65c01 0000000000000000 ffffffff82a3b1c0
00000000ffffffff 0000000000000000 0000000000000009 ffff8801b016f878
ffffffff813feb5a 0000000041b58ab3 ffffffff82e3260d ffffffff813fe981
Call Trace:
[<00000000426ed3cf>] __dump_stack lib/dump_stack.c:15 [inline]
[<00000000426ed3cf>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
[<00000000a43e3d00>] panic+0x1d9/0x3bd kernel/panic.c:180
[<00000000e89cd00f>] __warn.cold+0x2f/0x2f kernel/panic.c:546
[<000000007b57ec27>] warn_slowpath_null+0x2d/0x40 kernel/panic.c:589
[<00000000a3485fc7>] ext4_has_metadata_csum fs/ext4/ext4.h:2721 [inline]
[<00000000a3485fc7>] ext4_group_desc_csum.isra.0+0x537/0xa40
fs/ext4/super.c:2190
[<0000000081d91fc3>] ext4_group_desc_csum_verify+0x111/0x170
fs/ext4/super.c:2232
[<00000000c226df8c>] ext4_check_descriptors fs/ext4/super.c:2347 [inline]
[<00000000c226df8c>] ext4_fill_super+0x4fbe/0xb7a0 fs/ext4/super.c:3959
[<00000000ed67ae7c>] mount_bdev+0x2b8/0x360 fs/super.c:1110
[<00000000cc53110b>] ext4_mount+0x35/0x40 fs/ext4/super.c:5627
[<0000000046160e87>] mount_fs+0x27c/0x380 fs/super.c:1216
[<00000000bd1b91a1>] vfs_kern_mount.part.0+0xcd/0x4c0 fs/namespace.c:1000
[<000000002e89a4b6>] vfs_kern_mount fs/namespace.c:982 [inline]
[<000000002e89a4b6>] do_new_mount fs/namespace.c:2549 [inline]
[<000000002e89a4b6>] do_mount+0x3c4/0x2970 fs/namespace.c:2871
[<00000000f719d5f5>] SYSC_mount fs/namespace.c:3087 [inline]
[<00000000f719d5f5>] SyS_mount+0xab/0x120 fs/namespace.c:3064
[<00000000fb83ea02>] do_syscall_64+0x1ad/0x5c0 arch/x86/entry/common.c:288
[<00000000df7903c7>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
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.