[syzbot] [btrfs?] general protection fault in btrfs_finish_ordered_extent

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f01e9fed845 Merge tag 'linux-watchdog-6.5-rc2' of git://w..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=117b9b6ca80000
kernel config: https://syzkaller.appspot.com/x/.config?x=29fd3392a08741ef
dashboard link: https://syzkaller.appspot.com/bug?extid=5b82f0e951f8c2bcdb8f
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12f5014ca80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14f5adb0a80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d8b0db7be621/disk-3f01e9fe.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e54c8d8a4367/vmlinux-3f01e9fe.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a266546d6979/bzImage-3f01e9fe.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/954ae8a07707/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5b82f0...@syzkaller.appspotmail.com

RBP: 00007ffef40699e0 R08: 0000000000000000 R09: 0000000000000008
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007ffef4069a20 R14: 00007ffef4069a00 R15: 0000000000000004
</TASK>
BTRFS warning (device loop0): direct IO failed ino 263 op 0x8801 offset 0x4000 len 4096 err no 9
general protection fault, probably for non-canonical address 0xdffffc000000000c: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000060-0x0000000000000067]
CPU: 1 PID: 5096 Comm: syz-executor315 Not tainted 6.5.0-rc1-syzkaller-00006-g3f01e9fed845 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/03/2023
RIP: 0010:btrfs_finish_ordered_extent+0x43/0x3c0 fs/btrfs/ordered-data.c:375
Code: 4c 24 10 48 89 54 24 08 48 89 74 24 18 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 b8 4e f9 fd 49 8d 6e 60 49 89 ec 49 c1 ec 03 <41> 80 3c 1c 00 74 08 48 89 ef e8 7e 04 52 fe 4c 8b 7d 00 49 8d 9f
RSP: 0018:ffffc90003dcf438 EFLAGS: 00010206
RAX: ffffffff8392b4f8 RBX: dffffc0000000000 RCX: ffff888020f01dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000060 R08: 0000000000000000 R09: ffffffff838ef2c7
R10: 0000000000000003 R11: ffff888020f01dc0 R12: 000000000000000c
R13: 0000000000001000 R14: 0000000000000000 R15: ffff88814c43c300
FS: 0000555555a85300(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8a9d884140 CR3: 0000000079cdb000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
btrfs_dio_end_io+0x171/0x470 fs/btrfs/inode.c:7810
iomap_dio_submit_bio fs/iomap/direct-io.c:75 [inline]
iomap_dio_bio_iter+0xe15/0x1430 fs/iomap/direct-io.c:347
__iomap_dio_rw+0x11fa/0x2250 fs/iomap/direct-io.c:575
btrfs_dio_write+0xb6/0x100 fs/btrfs/inode.c:7884
btrfs_direct_write fs/btrfs/file.c:1526 [inline]
btrfs_do_write_iter+0x61c/0x1020 fs/btrfs/file.c:1667
do_iter_write+0x84f/0xde0 fs/read_write.c:860
vfs_writev fs/read_write.c:933 [inline]
do_pwritev+0x21a/0x360 fs/read_write.c:1030
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8a9d80cb29
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 00 00 90 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffef40699a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000148
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8a9d80cb29
RDX: 0000000000000002 RSI: 0000000020000240 RDI: 0000000000000005
RBP: 00007ffef40699e0 R08: 0000000000000000 R09: 0000000000000008
R10: 0000000000004000 R11: 0000000000000246 R12: 0000000000000006
R13: 00007ffef4069a20 R14: 00007ffef4069a00 R15: 0000000000000004
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:btrfs_finish_ordered_extent+0x43/0x3c0 fs/btrfs/ordered-data.c:375
Code: 4c 24 10 48 89 54 24 08 48 89 74 24 18 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 b8 4e f9 fd 49 8d 6e 60 49 89 ec 49 c1 ec 03 <41> 80 3c 1c 00 74 08 48 89 ef e8 7e 04 52 fe 4c 8b 7d 00 49 8d 9f
RSP: 0018:ffffc90003dcf438 EFLAGS: 00010206
RAX: ffffffff8392b4f8 RBX: dffffc0000000000 RCX: ffff888020f01dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000060 R08: 0000000000000000 R09: ffffffff838ef2c7
R10: 0000000000000003 R11: ffff888020f01dc0 R12: 000000000000000c
R13: 0000000000001000 R14: 0000000000000000 R15: ffff88814c43c300
FS: 0000555555a85300(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005609e4054978 CR3: 0000000079cdb000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: 4c 24 10 rex.WR and $0x10,%al
3: 48 89 54 24 08 mov %rdx,0x8(%rsp)
8: 48 89 74 24 18 mov %rsi,0x18(%rsp)
d: 49 89 fe mov %rdi,%r14
10: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx
17: fc ff df
1a: e8 b8 4e f9 fd callq 0xfdf94ed7
1f: 49 8d 6e 60 lea 0x60(%r14),%rbp
23: 49 89 ec mov %rbp,%r12
26: 49 c1 ec 03 shr $0x3,%r12
* 2a: 41 80 3c 1c 00 cmpb $0x0,(%r12,%rbx,1) <-- trapping instruction
2f: 74 08 je 0x39
31: 48 89 ef mov %rbp,%rdi
34: e8 7e 04 52 fe callq 0xfe5204b7
39: 4c 8b 7d 00 mov 0x0(%rbp),%r15
3d: 49 rex.WB
3e: 8d .byte 0x8d
3f: 9f lahf


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the bug is already fixed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to change bug's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has bisected this issue to:

commit b41b6f6937dc89e072b334e8d814487cb4692770
Author: Christoph Hellwig <h...@lst.de>
Date: Wed May 31 07:54:09 2023 +0000

btrfs: use btrfs_finish_ordered_extent to complete direct writes

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14761374a80000
start commit: 1c7873e33645 mm: lock newly mapped VMA with corrected orde..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=16761374a80000
console output: https://syzkaller.appspot.com/x/log.txt?x=12761374a80000
kernel config: https://syzkaller.appspot.com/x/.config?x=9831e2c2660aae77
dashboard link: https://syzkaller.appspot.com/bug?extid=5b82f0e951f8c2bcdb8f
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=109dcf08a80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13dadfb4a80000

Reported-by: syzbot+5b82f0...@syzkaller.appspotmail.com
Fixes: b41b6f6937dc ("btrfs: use btrfs_finish_ordered_extent to complete direct writes")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+5b82f0...@syzkaller.appspotmail.com

Tested on:

commit: 7e039738 btrfs: fix ordered extent split error handlin..
git tree: git://git.infradead.org/users/hch/misc.git btrfs-btrfs_dio_submit_io-err-handling
console output: https://syzkaller.appspot.com/x/log.txt?x=17c321eca80000
kernel config: https://syzkaller.appspot.com/x/.config?x=6d0f369ef5fb88c9
dashboard link: https://syzkaller.appspot.com/bug?extid=5b82f0e951f8c2bcdb8f
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.
Note: testing is done by a robot and is best-effort only.