kernel BUG in ext4_ext_insert_extent

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: cee407c5 Merge tag 'for-linus' of git://git.kernel.org/pub..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=15b1e60ad00000
kernel config: https://syzkaller.appspot.com/x/.config?x=8f67201de02a572b
dashboard link: https://syzkaller.appspot.com/bug?extid=9bb7ac675a88ae41fda9
compiler: Debian clang version 11.0.1-2
CC: [adilger...@dilger.ca linux...@vger.kernel.org linux-...@vger.kernel.org ty...@mit.edu]

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+9bb7ac...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/ext4/extents.c:2090!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 18382 Comm: syz-executor.2 Not tainted 5.12.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:ext4_ext_insert_extent+0x4c88/0x4cb0 fs/ext4/extents.c:2090
Code: 24 1c 01 00 00 80 e1 04 80 c9 03 38 c1 0f 8c a7 f2 ff ff 48 8d bc 24 1c 01 00 00 e8 32 04 b5 ff e9 95 f2 ff ff e8 e8 c7 70 ff <0f> 0b e8 e1 c7 70 ff 0f 0b e8 da c7 70 ff 0f 0b e8 d3 c7 70 ff 0f
RSP: 0018:ffffc9000244f888 EFLAGS: 00010283
RAX: ffffffff82078aa8 RBX: 0000000000003000 RCX: 0000000000040000
RDX: ffffc9000d011000 RSI: 0000000000011a29 RDI: 0000000000011a2a
RBP: 0000000000003000 R08: ffffffff820763da R09: fffffbfff1b6ae7e
R10: fffffbfff1b6ae7e R11: 0000000000000000 R12: ffff8881475d7240
R13: 1ffff11028ebae48 R14: ffff8881475d7200 R15: ffff888079e4206c
FS: 00007f2b919d3700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b3192e000 CR3: 000000007ca2d000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
ext4_ext_map_blocks+0x2bbb/0x6f30 fs/ext4/extents.c:4259
ext4_map_blocks+0x9fe/0x1b80 fs/ext4/inode.c:638
ext4_alloc_file_blocks+0x350/0xbf0 fs/ext4/extents.c:4425
ext4_zero_range fs/ext4/extents.c:4537 [inline]
ext4_fallocate+0xcfa/0x33d0 fs/ext4/extents.c:4674
vfs_fallocate+0x556/0x8b0 fs/open.c:311
ksys_fallocate fs/open.c:334 [inline]
__do_sys_fallocate fs/open.c:342 [inline]
__se_sys_fallocate fs/open.c:340 [inline]
__x64_sys_fallocate+0xb9/0x100 fs/open.c:340
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x465f69
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2b919d3188 EFLAGS: 00000246 ORIG_RAX: 000000000000011d
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 0000000000465f69
RDX: 0000000000008003 RSI: 0000000000000010 RDI: 0000000000000005
RBP: 00000000004bfa67 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000008020001 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007fffcd061e6f R14: 00007f2b919d3300 R15: 0000000000022000
Modules linked in:
---[ end trace 081933edd891baf3 ]---
RIP: 0010:ext4_ext_insert_extent+0x4c88/0x4cb0 fs/ext4/extents.c:2090
Code: 24 1c 01 00 00 80 e1 04 80 c9 03 38 c1 0f 8c a7 f2 ff ff 48 8d bc 24 1c 01 00 00 e8 32 04 b5 ff e9 95 f2 ff ff e8 e8 c7 70 ff <0f> 0b e8 e1 c7 70 ff 0f 0b e8 da c7 70 ff 0f 0b e8 d3 c7 70 ff 0f
RSP: 0018:ffffc9000244f888 EFLAGS: 00010283
RAX: ffffffff82078aa8 RBX: 0000000000003000 RCX: 0000000000040000
RDX: ffffc9000d011000 RSI: 0000000000011a29 RDI: 0000000000011a2a
RBP: 0000000000003000 R08: ffffffff820763da R09: fffffbfff1b6ae7e
R10: fffffbfff1b6ae7e R11: 0000000000000000 R12: ffff8881475d7240
R13: 1ffff11028ebae48 R14: ffff8881475d7200 R15: ffff888079e4206c
FS: 00007f2b919d3700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa1e84ab718 CR3: 000000007ca2d000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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[syzbot]

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