[syzbot] [ext4?] WARNING in ext4_iomap_begin (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 715abedee4cd Add linux-next specific files for 20230515
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=11d745dd280000
kernel config: https://syzkaller.appspot.com/x/.config?x=6a2745d066dda0ec
dashboard link: https://syzkaller.appspot.com/bug?extid=307da6ca5cb0d01d581a
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/d4d1d06b34b8/disk-715abede.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3ef33a86fdc8/vmlinux-715abede.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e0006b413ed1/bzImage-715abede.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+307da6...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 9503 at fs/ext4/inode.c:3326 ext4_iomap_begin+0x1ae/0x7a0 fs/ext4/inode.c:3326
Modules linked in:
CPU: 1 PID: 9503 Comm: syz-executor.1 Not tainted 6.4.0-rc2-next-20230515-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
RIP: 0010:ext4_iomap_begin+0x1ae/0x7a0 fs/ext4/inode.c:3326
Code: 83 c0 01 38 d0 7c 08 84 d2 0f 85 ee 05 00 00 41 0f b7 9f ba 05 00 00 31 ff 89 de e8 4c a5 57 ff 66 85 db 74 5c e8 42 a9 57 ff <0f> 0b 41 bd de ff ff ff e8 35 a9 57 ff 48 b8 00 00 00 00 00 fc ff
RSP: 0018:ffffc90006a1f560 EFLAGS: 00010216
RAX: 000000000002ebb2 RBX: 00000000000000a4 RCX: ffffc90004103000
RDX: 0000000000040000 RSI: ffffffff822c7a6e RDI: 0000000000000003
RBP: 0000000000000080 R08: 0000000000000003 R09: 0000000000000000
R10: 00000000000000a4 R11: 0000000000094001 R12: 000000000000000b
R13: ffff88803f00bf7a R14: ffffc90006a1f838 R15: ffff88803f00beb0
FS: 00007f3cc037b700(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000080 CR3: 000000008f1f7000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
iomap_iter+0x446/0x10e0 fs/iomap/iter.c:91
__iomap_dio_rw+0x7a5/0x1f90 fs/iomap/direct-io.c:597
iomap_dio_rw+0x40/0xa0 fs/iomap/direct-io.c:688
ext4_dio_read_iter fs/ext4/file.c:94 [inline]
ext4_file_read_iter+0x4be/0x690 fs/ext4/file.c:145
call_read_iter include/linux/fs.h:1862 [inline]
generic_file_splice_read+0x182/0x4b0 fs/splice.c:419
do_splice_to+0x1b9/0x240 fs/splice.c:902
splice_direct_to_actor+0x2ab/0x8a0 fs/splice.c:973
do_splice_direct+0x1ab/0x280 fs/splice.c:1082
do_sendfile+0xb19/0x12c0 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1308
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f3cbf68c199
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3cc037b168 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f3cbf7abf80 RCX: 00007f3cbf68c199
RDX: 0000000000000000 RSI: 0000000000000005 RDI: 0000000000000004
RBP: 00007f3cbf6e7ca1 R08: 0000000000000000 R09: 0000000000000000
R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffebb26bb1f R14: 00007f3cc037b300 R15: 0000000000022000
</TASK>


---
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If the bug is a duplicate of another bug, reply with:
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If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 9ed22ae6be81 Merge tag 'spi-fix-v6.6-rc3' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=126a50d6680000
kernel config: https://syzkaller.appspot.com/x/.config?x=12da82ece7bf46f9
dashboard link: https://syzkaller.appspot.com/bug?extid=307da6ca5cb0d01d581a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15eb672e680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16219bc6680000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f059028ccc85/disk-9ed22ae6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3b01e6cd5f62/vmlinux-9ed22ae6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/32202918d16c/bzImage-9ed22ae6.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/38533c948c72/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+307da6...@syzkaller.appspotmail.com

------------[ cut here ]------------

WARNING: CPU: 0 PID: 5195 at fs/ext4/inode.c:3338 ext4_iomap_begin+0xa9b/0xd30
Modules linked in:
CPU: 0 PID: 5195 Comm: syz-executor392 Not tainted 6.6.0-rc3-syzkaller-00055-g9ed22ae6be81 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:ext4_iomap_begin+0xa9b/0xd30 fs/ext4/inode.c:3338
Code: d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 ce 3d 4c ff 49 be 00 00 00 00 00 fc ff df 48 8b 5c 24 48 e9 65 ff ff ff e8 b5 3d 4c ff <0f> 0b 41 bc de ff ff ff e9 8f f6 ff ff 89 d9 80 e1 07 38 c1 0f 8c
RSP: 0018:ffffc9000405f580 EFLAGS: 00010293
RAX: ffffffff8241ccbb RBX: 0000000010000000 RCX: ffff88802234d940
RDX: 0000000000000000 RSI: 00000000000000bc RDI: 0000000000000000
RBP: ffffc9000405f6f0 R08: ffffffff8241c408 R09: 1ffff1100eff5b4a
R10: dffffc0000000000 R11: ffffed100eff5b4b R12: 00000000000000bc
R13: 1ffff1100eff5baf R14: 000000000000000b R15: 0000000000000016
FS: 00007f68b788c6c0(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f68b788cd58 CR3: 000000006b9c0000 CR4: 00000000003506f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>

iomap_iter+0x677/0xec0 fs/iomap/iter.c:91
__iomap_dio_rw+0xe2e/0x2370 fs/iomap/direct-io.c:658
iomap_dio_rw+0x46/0xa0 fs/iomap/direct-io.c:748
ext4_dio_write_iter fs/ext4/file.c:605 [inline]
ext4_file_write_iter+0x165f/0x1ad0 fs/ext4/file.c:715
call_write_iter include/linux/fs.h:1956 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x782/0xaf0 fs/read_write.c:584
ksys_pwrite64 fs/read_write.c:699 [inline]
__do_sys_pwrite64 fs/read_write.c:709 [inline]
__se_sys_pwrite64 fs/read_write.c:706 [inline]
__x64_sys_pwrite64+0x1aa/0x230 fs/read_write.c:706
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: 0033:0x7f68bfbf0b59
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 18 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f68b788c218 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f68b788c6c0 RCX: 00007f68bfbf0b59
RDX: 0000000000000001 RSI: 0000000020000100 RDI: 0000000000000005
RBP: 00007f68bfc796d8 R08: 00007ffd6a04dbc7 R09: 0000000000000000
R10: 000000000000b114 R11: 0000000000000246 R12: ffffffffffffffb0
R13: 00007f68bfc796d0 R14: 00007f68bfc45840 R15: 0030656c69662f2e
</TASK>


---
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.

[syzbot]

syzbot has bisected this issue to:

commit 310ee0902b8d9d0a13a5a13e94688a5863fa29c2
Author: Brian Foster <bfo...@redhat.com>
Date: Tue Mar 14 13:07:59 2023 +0000

ext4: allow concurrent unaligned dio overwrites

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=10a8442a680000
start commit: 9ed22ae6be81 Merge tag 'spi-fix-v6.6-rc3' of git://git.ker..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=12a8442a680000
console output: https://syzkaller.appspot.com/x/log.txt?x=14a8442a680000

kernel config: https://syzkaller.appspot.com/x/.config?x=12da82ece7bf46f9
dashboard link: https://syzkaller.appspot.com/bug?extid=307da6ca5cb0d01d581a

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15eb672e680000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16219bc6680000

Reported-by: syzbot+307da6...@syzkaller.appspotmail.com
Fixes: 310ee0902b8d ("ext4: allow concurrent unaligned dio overwrites")

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

[Brian Foster]

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

diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 6830ea3a6c59..cad659c2e9cc 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -537,6 +537,9 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
bool ilock_shared = true;
int dio_flags = 0;

+ if (ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
+ ilock_shared = false;
+
/*
* Quick check here without any i_rwsem lock to see if it is extending
* IO. A more reliable check is done in ext4_dio_write_checks() with

[syzbot]

Hello,

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

Reported-and-tested-by: syzbot+307da6...@syzkaller.appspotmail.com

Tested on:

commit: 71e58659 Merge tag 'gpio-fixes-for-v6.6-rc4' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=176a0d01680000

kernel config: https://syzkaller.appspot.com/x/.config?x=12da82ece7bf46f9
dashboard link: https://syzkaller.appspot.com/bug?extid=307da6ca5cb0d01d581a

compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=16d320b2680000

Note: testing is done by a robot and is best-effort only.

[Brian Foster]

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

diff --git a/fs/ext4/file.c b/fs/ext4/file.c

index 6830ea3a6c59..19ff9be02ea7 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -569,6 +569,7 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
return ext4_buffered_write_iter(iocb, from);
}

+ ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
ret = ext4_dio_write_checks(iocb, from, &ilock_shared, &extend,
&unwritten, &dio_flags);
if (ret <= 0)
@@ -579,7 +580,7 @@ static ssize_t ext4_dio_write_iter(struct kiocb *iocb, struct iov_iter *from)
* to allocate blocks for DIO. We know the inode does not have any
* inline data now because ext4_dio_supported() checked for that.
*/
- ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+ //ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);

offset = iocb->ki_pos;
count = ret;

[syzbot]

Hello,

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

Reported-and-tested-by: syzbot+307da6...@syzkaller.appspotmail.com

Tested on:

commit: 1c84724c Merge tag 'slab-fixes-for-6.6-rc4' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12a06bae680000

kernel config: https://syzkaller.appspot.com/x/.config?x=12da82ece7bf46f9
dashboard link: https://syzkaller.appspot.com/bug?extid=307da6ca5cb0d01d581a
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=160c17c6680000