[Android 5.10] kernel BUG in ext4_mb_normalize_request

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e253c52bbdfc Merge 5.10.247 into android13-5.10-lts
git tree: android13-5.10-lts
console output: https://syzkaller.appspot.com/x/log.txt?x=10cdbdc2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=5193c33e6e6dcf8b
dashboard link: https://syzkaller.appspot.com/bug?extid=16dfafdbe48358333904
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17a4dd92580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13633a2a580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/1f48e3a38826/disk-e253c52b.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/17f909517783/vmlinux-e253c52b.xz
kernel image: https://storage.googleapis.com/syzbot-assets/1fc1230e0a59/bzImage-e253c52b.xz
mounted in repro #1: https://storage.googleapis.com/syzbot-assets/db33fd9aab28/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=11f9e31a580000)
mounted in repro #2: https://storage.googleapis.com/syzbot-assets/0c45b2b6dbaf/mount_2.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=174dbdc2580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+16dfaf...@syzkaller.appspotmail.com

------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:3676!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
RIP: 0010:ext4_mb_normalize_request+0x1283/0x12e0 fs/ext4/mballoc.c:3676
Code: 4d a8 80 e1 07 80 c1 03 38 c1 0f 8c 79 fc ff ff 48 8b 7d a8 e8 7e c8 cb ff e9 6b fc ff ff e8 f4 d9 91 ff 0f 0b e8 ed d9 91 ff <0f> 0b e8 e6 d9 91 ff 0f 0b e8 df d9 91 ff 0f 0b e8 d8 d9 91 ff 0f
RSP: 0018:ffffc90000077410 EFLAGS: 00010293

RAX: ffffffff81d1ca93 RBX: 0000000000000027 RCX: ffff88810024a780
RDX: 0000000000000000 RSI: 0000000000000027 RDI: 0000000000000030
RBP: ffffc900000774f0 R08: 0000000000000004 R09: 0000000000000003
R10: fffff5200000ee74 R11: 1ffff9200000ee74 R12: 0000000000000030
R13: 0000000000000027 R14: ffff888120bee498 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa63fb76000 CR3: 00000001117ab000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
ext4_mb_new_blocks+0xc21/0x42f0 fs/ext4/mballoc.c:5233
ext4_ext_map_blocks+0x167f/0x5d80 fs/ext4/extents.c:4335
ext4_map_blocks+0x978/0x1bc0 fs/ext4/inode.c:674
ext4_convert_unwritten_extents+0x21c/0x3f0 fs/ext4/extents.c:4862
ext4_convert_unwritten_io_end_vec+0x103/0x180 fs/ext4/extents.c:4901
ext4_end_io_end fs/ext4/page-io.c:189 [inline]
ext4_do_flush_completed_IO fs/ext4/page-io.c:262 [inline]
ext4_end_io_rsv_work+0x2b9/0x600 fs/ext4/page-io.c:276
process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447
kthread+0x346/0x3d0 kernel/kthread.c:313
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
Modules linked in:
---[ end trace de4eb0693b717b9a ]---
RIP: 0010:ext4_mb_normalize_request+0x1283/0x12e0 fs/ext4/mballoc.c:3676
Code: 4d a8 80 e1 07 80 c1 03 38 c1 0f 8c 79 fc ff ff 48 8b 7d a8 e8 7e c8 cb ff e9 6b fc ff ff e8 f4 d9 91 ff 0f 0b e8 ed d9 91 ff <0f> 0b e8 e6 d9 91 ff 0f 0b e8 df d9 91 ff 0f 0b e8 d8 d9 91 ff 0f
RSP: 0018:ffffc90000077410 EFLAGS: 00010293
RAX: ffffffff81d1ca93 RBX: 0000000000000027 RCX: ffff88810024a780
RDX: 0000000000000000 RSI: 0000000000000027 RDI: 0000000000000030
RBP: ffffc900000774f0 R08: 0000000000000004 R09: 0000000000000003
R10: fffff5200000ee74 R11: 1ffff9200000ee74 R12: 0000000000000030
R13: 0000000000000027 R14: ffff888120bee498 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa63fb76000 CR3: 000000000620f000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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