EXT4-fs error (device loop2) in ext4_reserve_inode_write:5900: Corrupt filesystem
EXT4-fs error (device loop2): ext4_truncate:4389: inode #19: comm syz-executor.2: mark_inode_dirty error
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:826 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xbea/0xe30 fs/ext4/extents.c:945
Read of size 4 at addr ffff8881232b6784 by task syz-executor.2/430

CPU: 1 PID: 430 Comm: syz-executor.2 Not tainted 5.10.234-syzkaller-1006652-g3f5f2283d684 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x81/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0x179/0x1c0 mm/kasan/report.c:452
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 ext4_ext_binsearch fs/ext4/extents.c:826 [inline]
 ext4_find_extent+0xbea/0xe30 fs/ext4/extents.c:945
 ext4_ext_map_blocks+0x26a/0x6ee0 fs/ext4/extents.c:4159
 ext4_map_blocks+0xa65/0x1d10 fs/ext4/inode.c:673
 mpage_map_one_extent fs/ext4/inode.c:2451 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2504 [inline]
 ext4_writepages+0x148b/0x3c00 fs/ext4/inode.c:2872
 do_writepages+0x12e/0x270 mm/page-writeback.c:2380
 __filemap_fdatawrite_range+0x33c/0x3f0 mm/filemap.c:427
 file_write_and_wait_range+0x89/0x120 mm/filemap.c:766
 ext4_sync_file+0x1a2/0xa30 fs/ext4/fsync.c:151
 vfs_fsync_range+0x17b/0x190 fs/sync.c:202
 generic_write_sync include/linux/fs.h:2912 [inline]
 ext4_buffered_write_iter+0x565/0x610 fs/ext4/file.c:278
 ext4_file_write_iter+0x193/0x1c80 fs/ext4/file.c:685
 call_write_iter include/linux/fs.h:2058 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0xb4c/0xe70 fs/read_write.c:605
 ksys_write+0x199/0x2c0 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:667
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fd9a107a859
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007fd9a0bfd0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd9a1199f80 RCX: 00007fd9a107a859
RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000005
RBP: 00007fd9a10d6ad0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd9a1199f80 R15: 00007fff47340f78

The buggy address belongs to the page:
page:ffffea00048cad80 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x1232b6
flags: 0x4000000000000000()
raw: 4000000000000000 ffffea00048cadc8 ffffea00048cad48 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner info is not present (never set?)

Memory state around the buggy address:
 ffff8881232b6680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881232b6700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8881232b6780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff8881232b6800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8881232b6880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
------------[ cut here ]------------
kernel BUG at fs/ext4/inode.c:2463!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 430 Comm: syz-executor.2 Tainted: G    B             5.10.234-syzkaller-1006652-g3f5f2283d684 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:mpage_map_one_extent fs/ext4/inode.c:2463 [inline]
RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2504 [inline]
RIP: 0010:ext4_writepages+0x3b44/0x3c00 fs/ext4/inode.c:2872
Code: 00 74 08 48 89 df e8 fb c5 c9 ff 48 8b 3b 48 8b 74 24 28 48 8b 54 24 50 44 89 e1 45 89 f8 e8 93 de 07 00 eb 5d e8 9c 26 8c ff <0f> 0b e8 95 26 8c ff eb 3b e8 8e 26 8c ff eb 77 e8 87 26 8c ff 31
RSP: 0018:ffffc90001277300 EFLAGS: 00010293
RAX: ffffffff81de98c4 RBX: dffffc0000000000 RCX: ffff888112b3cf00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900012776f0 R08: ffffffff81de74c9 R09: ffffed10244496c9
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90001277610
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fd9a0bfd6c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f76a42add58 CR3: 0000000112f7d000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_writepages+0x12e/0x270 mm/page-writeback.c:2380
 __filemap_fdatawrite_range+0x33c/0x3f0 mm/filemap.c:427
 file_write_and_wait_range+0x89/0x120 mm/filemap.c:766
 ext4_sync_file+0x1a2/0xa30 fs/ext4/fsync.c:151
 vfs_fsync_range+0x17b/0x190 fs/sync.c:202
 generic_write_sync include/linux/fs.h:2912 [inline]
 ext4_buffered_write_iter+0x565/0x610 fs/ext4/file.c:278
 ext4_file_write_iter+0x193/0x1c80 fs/ext4/file.c:685
 call_write_iter include/linux/fs.h:2058 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0xb4c/0xe70 fs/read_write.c:605
 ksys_write+0x199/0x2c0 fs/read_write.c:658
 __do_sys_write fs/read_write.c:670 [inline]
 __se_sys_write fs/read_write.c:667 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:667
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fd9a107a859
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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:00007fd9a0bfd0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fd9a1199f80 RCX: 00007fd9a107a859
RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000005
RBP: 00007fd9a10d6ad0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd9a1199f80 R15: 00007fff47340f78
Modules linked in:
---[ end trace deffdce09b4f2eb3 ]---
RIP: 0010:mpage_map_one_extent fs/ext4/inode.c:2463 [inline]
RIP: 0010:mpage_map_and_submit_extent fs/ext4/inode.c:2504 [inline]
RIP: 0010:ext4_writepages+0x3b44/0x3c00 fs/ext4/inode.c:2872
Code: 00 74 08 48 89 df e8 fb c5 c9 ff 48 8b 3b 48 8b 74 24 28 48 8b 54 24 50 44 89 e1 45 89 f8 e8 93 de 07 00 eb 5d e8 9c 26 8c ff <0f> 0b e8 95 26 8c ff eb 3b e8 8e 26 8c ff eb 77 e8 87 26 8c ff 31
RSP: 0018:ffffc90001277300 EFLAGS: 00010293

RAX: ffffffff81de98c4 RBX: dffffc0000000000 RCX: ffff888112b3cf00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900012776f0 R08: ffffffff81de74c9 R09: ffffed10244496c9
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffc90001277610
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fd9a0bfd6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f33b290c000 CR3: 0000000112f7d000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400