[Android 5.15] kernel BUG in ext4_mb_normalize_request

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e714749f59d3 Merge 6167af934f95 ("fbdev: smscufx: properly..
git tree: android13-5.15-lts
console output: https://syzkaller.appspot.com/x/log.txt?x=172cc952580000
kernel config: https://syzkaller.appspot.com/x/.config?x=deffac0a782f1cb0
dashboard link: https://syzkaller.appspot.com/bug?extid=c362a8a885b6f7fab3fa
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=109b035a580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16f2b0ba580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9da76ed5d123/disk-e714749f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5e636b3a3c0c/vmlinux-e714749f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3d407deb9662/bzImage-e714749f.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6ba30abfebc6/mount_0.gz
fsck result: failed (log: https://syzkaller.appspot.com/x/fsck.log?x=117b935a580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c362a8...@syzkaller.appspotmail.com

EXT4-fs error (device loop2): ext4_mb_mark_diskspace_used:3887: comm syz.2.66: Allocating blocks 497-513 which overlap fs metadata
EXT4-fs (loop2): pa ffff88812e4363f0: logic 128, phys. 385, len 8
EXT4-fs error (device loop2): ext4_mb_release_inode_pa:4904: group 0, free 0, pa_free 1
------------[ cut here ]------------
kernel BUG at fs/ext4/mballoc.c:4258!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 611 Comm: syz.2.66 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:ext4_mb_normalize_request+0x1944/0x1990 fs/ext4/mballoc.c:4258
Code: 00 e9 8e fa ff ff e8 4b eb 8b ff 0f 0b e8 44 eb 8b ff 0f 0b e8 3d eb 8b ff e9 b7 fb ff ff e8 33 eb 8b ff 0f 0b e8 2c eb 8b ff <0f> 0b e8 25 eb 8b ff 0f 0b e8 1e eb 8b ff 48 8b 45 80 42 80 3c 28
RSP: 0018:ffffc900032aec68 EFLAGS: 00010293
RAX: ffffffff81dde1d4 RBX: 0000000000000060 RCX: ffff88811d0e62c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc900032aed50 R08: ffff88812e43b50f R09: 1ffff11025c876a1
R10: dffffc0000000000 R11: ffffed1025c876a2 R12: 000000000000001f
R13: dffffc0000000000 R14: 0000000000000000 R15: 000000000000001f
FS: 00007f8ebb7506c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000034000 CR3: 000000012afbf000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_mb_new_blocks+0xbfd/0x42c0 fs/ext4/mballoc.c:5781
ext4_ext_map_blocks+0x1722/0x61e0 fs/ext4/extents.c:4341
ext4_map_blocks+0x988/0x1b30 fs/ext4/inode.c:674
mpage_map_one_extent fs/ext4/inode.c:2421 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2474 [inline]
ext4_writepages+0x123f/0x3090 fs/ext4/inode.c:2842
do_writepages+0x473/0x6c0 mm/page-writeback.c:2388
filemap_fdatawrite_wbc+0x1f4/0x250 mm/filemap.c:409
__filemap_fdatawrite_range mm/filemap.c:442 [inline]
file_write_and_wait_range+0x14d/0x220 mm/filemap.c:819
ext4_sync_file+0x1a9/0xa10 fs/ext4/fsync.c:151
vfs_fsync_range+0x190/0x1a0 fs/sync.c:188
generic_write_sync include/linux/fs.h:3038 [inline]
ext4_buffered_write_iter+0x5d0/0x670 fs/ext4/file.c:277
ext4_file_write_iter+0x440/0x1540 fs/ext4/file.c:-1
call_write_iter include/linux/fs.h:2212 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0x835/0xfd0 fs/read_write.c:594
ksys_pwrite64 fs/read_write.c:701 [inline]
__do_sys_pwrite64 fs/read_write.c:711 [inline]
__se_sys_pwrite64 fs/read_write.c:708 [inline]
__x64_sys_pwrite64+0x197/0x220 fs/read_write.c:708
x64_sys_call+0xa6/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:19
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f8ebb8ed799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8ebb750028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f8ebbb66fa0 RCX: 00007f8ebb8ed799
RDX: 00000000200000c1 RSI: 00002000000000c0 RDI: 0000000000000007
RBP: 00007f8ebb983bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000009000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8ebbb67038 R14: 00007f8ebbb66fa0 R15: 00007ffd7c811868
</TASK>
Modules linked in:
---[ end trace e49784af35ca9436 ]---
RIP: 0010:ext4_mb_normalize_request+0x1944/0x1990 fs/ext4/mballoc.c:4258
Code: 00 e9 8e fa ff ff e8 4b eb 8b ff 0f 0b e8 44 eb 8b ff 0f 0b e8 3d eb 8b ff e9 b7 fb ff ff e8 33 eb 8b ff 0f 0b e8 2c eb 8b ff <0f> 0b e8 25 eb 8b ff 0f 0b e8 1e eb 8b ff 48 8b 45 80 42 80 3c 28
RSP: 0018:ffffc900032aec68 EFLAGS: 00010293
RAX: ffffffff81dde1d4 RBX: 0000000000000060 RCX: ffff88811d0e62c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc900032aed50 R08: ffff88812e43b50f R09: 1ffff11025c876a1
R10: dffffc0000000000 R11: ffffed1025c876a2 R12: 000000000000001f
R13: dffffc0000000000 R14: 0000000000000000 R15: 000000000000001f
FS: 00007f8ebb7506c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000034000 CR3: 000000012afbf000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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