[v6.1] WARNING in ext4_iomap_begin (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 344a09659766 Linux 6.1.131
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=15bd843f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=1eebf09bc04ebd78
dashboard link: https://syzkaller.appspot.com/bug?extid=4a5bebb2e92f052563af
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/bccba205a29a/disk-344a0965.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/bdca79b3b5db/vmlinux-344a0965.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6c2271a91ef3/bzImage-344a0965.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4a5beb...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 14176 at fs/ext4/inode.c:3465 ext4_iomap_begin+0xa8f/0xd20
Modules linked in:
CPU: 1 PID: 14176 Comm: syz.6.2086 Not tainted 6.1.131-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:ext4_iomap_begin+0xa8f/0xd20 fs/ext4/inode.c:3465
Code: d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 ba 22 51 ff 49 be 00 00 00 00 00 fc ff df 48 8b 5c 24 48 e9 65 ff ff ff e8 a1 22 51 ff <0f> 0b 41 bc de ff ff ff e9 97 f6 ff ff 89 d9 80 e1 07 38 c1 0f 8c
RSP: 0000:ffffc900033df580 EFLAGS: 00010287
RAX: ffffffff8239871f RBX: 0000000010000000 RCX: 0000000000080000
RDX: ffffc90018b01000 RSI: 0000000000009eb3 RDI: 0000000000009eb4
RBP: ffffc900033df6f0 R08: ffffffff82397e74 R09: ffffed100a1ba14c
R10: 0000000000000000 R11: dffffc0000000001 R12: 00000000000000d4
R13: 1ffff1100a1ba1b0 R14: 000000000000000b R15: 0000000000000000
FS: 00007f776d65e6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000040 CR3: 000000005c0c2000 CR4: 00000000003506e0
Call Trace:
<TASK>
iomap_iter+0x6d8/0x10a0 fs/iomap/iter.c:91
__iomap_dio_rw+0xde9/0x2130 fs/iomap/direct-io.c:601
iomap_dio_rw+0x42/0xa0 fs/iomap/direct-io.c:690
ext4_dio_write_iter fs/ext4/file.c:557 [inline]
ext4_file_write_iter+0x1513/0x1930 fs/ext4/file.c:677
call_write_iter include/linux/fs.h:2265 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x857/0xbc0 fs/read_write.c:584
ksys_write+0x19c/0x2c0 fs/read_write.c:637
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f776c78d169
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f776d65e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f776c9a6080 RCX: 00007f776c78d169
RDX: 0000000000000078 RSI: 0000200000000640 RDI: 0000000000000004
RBP: 00007f776c80e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f776c9a6080 R15: 00007ffe111ed758
</TASK>


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: ac7079a42ea5 Linux 6.1.137
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=161618f4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=b6c9ee6fabde22af
dashboard link: https://syzkaller.appspot.com/bug?extid=4a5bebb2e92f052563af
compiler: Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1605fa70580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15cefb68580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/235ed7912afd/disk-ac7079a4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/66591056046a/vmlinux-ac7079a4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/11e3c8def63d/bzImage-ac7079a4.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/9f64b12afe1e/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=16baa8f4580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4a5beb...@syzkaller.appspotmail.com

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

WARNING: CPU: 1 PID: 4281 at fs/ext4/inode.c:3466 ext4_iomap_begin+0x977/0xae0 fs/ext4/inode.c:3466
Modules linked in:
CPU: 1 PID: 4281 Comm: syz-executor959 Not tainted 6.1.137-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
RIP: 0010:ext4_iomap_begin+0x977/0xae0 fs/ext4/inode.c:3466
Code: 3b 84 24 20 01 00 00 75 6d 44 89 f0 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 43 a2 5d ff e9 73 ff ff ff e8 39 a2 5d ff <0f> 0b 41 be de ff ff ff 49 bf 00 00 00 00 00 fc ff df eb 85 89 d9
RSP: 0018:ffffc90003d37020 EFLAGS: 00010293
RAX: ffffffff82232167 RBX: ffff888074782b9a RCX: ffff88801bfe8000
RDX: 0000000000000000 RSI: 00000000000000d4 RDI: 0000000000000000
RBP: ffffc90003d37190 R08: dffffc0000000000 R09: ffffed100e8f050f
R10: ffffed100e8f050f R11: 1ffff1100e8f050e R12: 00000000000000d4
R13: 1ffff1100e8f0573 R14: 000000000000000a R15: 0000000000000000
FS: 00007fe3f68e66c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000

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

CR2: 00007fe3f68c5d58 CR3: 000000001ebb1000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
iomap_iter+0x6c6/0x1040 fs/iomap/iter.c:91
__iomap_dio_rw+0xcba/0x1dd0 fs/iomap/direct-io.c:601
iomap_dio_rw+0x41/0xa0 fs/iomap/direct-io.c:690
ext4_dio_write_iter fs/ext4/file.c:557 [inline]
ext4_file_write_iter+0x1262/0x16e0 fs/ext4/file.c:677
do_iter_readv_writev fs/read_write.c:-1 [inline]
do_iter_write+0x62d/0xaf0 fs/read_write.c:861
iter_file_splice_write+0x665/0xc50 fs/splice.c:685
do_splice_from fs/splice.c:763 [inline]
direct_splice_actor+0xe1/0x130 fs/splice.c:950
splice_direct_to_actor+0x480/0xb60 fs/splice.c:896
do_splice_direct+0x1b0/0x2b0 fs/splice.c:1002
do_sendfile+0x5cc/0xeb0 fs/read_write.c:1255
__do_sys_sendfile64 fs/read_write.c:1323 [inline]
__se_sys_sendfile64+0x13b/0x190 fs/read_write.c:1309
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe3f694a839
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 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:00007fe3f68e6218 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fe3f69d1618 RCX: 00007fe3f694a839
RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000004
RBP: 00007fe3f69d1610 R08: 00007ffdc422fdf7 R09: 0000000000000000
R10: 0000000000014000 R11: 0000000000000246 R12: 00007fe3f699e7a4
R13: 0000200000000000 R14: 0000003202000000 R15: 0000200000000180
</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 suspects this issue was fixed by commit:

commit 74088456b034ca0b32d45d270caae4dbb73e129e
Author: Zhang Yi <yi.z...@huawei.com>
Date: Tue May 6 01:20:09 2025 +0000

ext4: ensure i_size is smaller than maxbytes

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=16f7f58c580000
start commit: ac7079a42ea5 Linux 6.1.137
git tree: linux-6.1.y

kernel config: https://syzkaller.appspot.com/x/.config?x=b6c9ee6fabde22af
dashboard link: https://syzkaller.appspot.com/bug?extid=4a5bebb2e92f052563af

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1605fa70580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=15cefb68580000

If the result looks correct, please mark the issue as fixed by replying with:

#syz fix: ext4: ensure i_size is smaller than maxbytes

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