syz test

[Tadeusz Struk]

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
kernel BUG in ext4_writepages

------------[ cut here ]------------
kernel BUG at fs/ext4/inode.c:2721!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 413 Comm: syz-executor.0 Not tainted 5.19.0-rc7-syzkaller-00190-g70664fc10c0d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
RIP: 0010:ext4_writepages+0x38ff/0x3920 fs/ext4/inode.c:2720
Code: e8 06 3b 8a ff 84 db 75 2f e8 ed 37 8a ff 48 bb 00 00 00 00 00 fc ff df 4c 8b bc 24 98 00 00 00 e9 6b cc ff ff e8 d1 37 8a ff <0f> 0b e8 ca 37 8a ff e8 75 2d 19 ff eb 9a e8 be 37 8a ff e8 69 2d
RSP: 0018:ffffc900029af280 EFLAGS: 00010293
RAX: ffffffff81e7228f RBX: 0000008000000000 RCX: ffff88810d058000
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc900029af670 R08: ffffffff81e6f13f R09: ffffed1023b99b44
R10: ffffed1023b99b44 R11: 1ffff11023b99b43 R12: ffffc900029af8a0
R13: ffff88810f16e000 R14: 0000008410000000 R15: ffff88810f16e000
FS: 00007f4a6ba41700(0000) GS:ffff8881f7300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002580 CR3: 000000010d45b000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
do_writepages+0x399/0x650 mm/page-writeback.c:2443
filemap_fdatawrite_wbc+0x14a/0x1b0 mm/filemap.c:388
__filemap_fdatawrite_range mm/filemap.c:421 [inline]
file_write_and_wait_range+0x1e7/0x2f0 mm/filemap.c:779
ext4_sync_file+0x19e/0xa00 fs/ext4/fsync.c:151
vfs_fsync_range+0x17b/0x190 fs/sync.c:188
generic_write_sync include/linux/fs.h:2731 [inline]
ext4_buffered_write_iter+0x488/0x530 fs/ext4/file.c:277
ext4_file_write_iter+0x449/0x1ba0
call_write_iter include/linux/fs.h:2058 [inline]
new_sync_write fs/read_write.c:504 [inline]
vfs_write+0xbb4/0xf30 fs/read_write.c:591
ksys_write+0x198/0x2c0 fs/read_write.c:644
__do_sys_write fs/read_write.c:656 [inline]
__se_sys_write fs/read_write.c:653 [inline]
__x64_sys_write+0x7b/0x90 fs/read_write.c:653
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2f/0x50 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f4a6a8890e9
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:00007f4a6ba41168 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f4a6a99bf60 RCX: 00007f4a6a8890e9
RDX: 0000000000000016 RSI: 0000000020002580 RDI: 0000000000000009
RBP: 00007f4a6a8e308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffdd7fd193f R14: 00007f4a6ba41300 R15: 0000000000022000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:ext4_writepages+0x38ff/0x3920 fs/ext4/inode.c:2720
Code: e8 06 3b 8a ff 84 db 75 2f e8 ed 37 8a ff 48 bb 00 00 00 00 00 fc ff df 4c 8b bc 24 98 00 00 00 e9 6b cc ff ff e8 d1 37 8a ff <0f> 0b e8 ca 37 8a ff e8 75 2d 19 ff eb 9a e8 be 37 8a ff e8 69 2d
RSP: 0018:ffffc900029af280 EFLAGS: 00010293
RAX: ffffffff81e7228f RBX: 0000008000000000 RCX: ffff88810d058000
RDX: 0000000000000000 RSI: 0000008000000000 RDI: 0000000000000000
RBP: ffffc900029af670 R08: ffffffff81e6f13f R09: ffffed1023b99b44
R10: ffffed1023b99b44 R11: 1ffff11023b99b43 R12: ffffc900029af8a0
R13: ffff88810f16e000 R14: 0000008410000000 R15: ffff88810f16e000
FS: 00007f4a6ba41700(0000) GS:ffff8881f7300000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020002580 CR3: 000000010d45b000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


Tested on:

commit: 70664fc1 Merge tag 'riscv-for-linus-5.19-rc8' of git:/..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=10988c5a080000
kernel config: https://syzkaller.appspot.com/x/.config?x=ae96286e23b1e962
dashboard link: https://syzkaller.appspot.com/bug?extid=bd13648a53ed6933ca49
compiler: Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2

Note: no patches were applied.