==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:826 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xbab/0xdb0 fs/ext4/extents.c:945
Read of size 4 at addr ffff88812265d784 by task syz-executor.3/465

CPU: 1 PID: 465 Comm: syz-executor.3 Not tainted 5.10.226-syzkaller-1003431-ge5e5644ea27f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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+0xbab/0xdb0 fs/ext4/extents.c:945
 ext4_ext_map_blocks+0x26a/0x6ee0 fs/ext4/extents.c:4138
 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:2875 [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:2021 [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: 0033:0x7ff1f8ca6859
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:00007ff1f88290c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff1f8dc5f80 RCX: 00007ff1f8ca6859
RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000006
RBP: 00007ff1f8d02ad0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007ff1f8dc5f80 R15: 00007ffe129727c8

The buggy address belongs to the page:
page:ffffea0004899740 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12265d
flags: 0x4000000000000000()
raw: 4000000000000000 ffffea0004899788 ffffea0004899708 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Movable, gfp_mask 0x100cca(GFP_HIGHUSER_MOVABLE), pid 480, ts 49063347737, free_ts 49434980062
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x166/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348
 __alloc_pages include/linux/gfp.h:544 [inline]
 __alloc_pages_node include/linux/gfp.h:557 [inline]
 alloc_pages_node include/linux/gfp.h:571 [inline]
 alloc_pages include/linux/gfp.h:590 [inline]
 shmem_alloc_page+0x257/0x420 mm/shmem.c:1580
 shmem_alloc_and_acct_page+0x395/0x8e0 mm/shmem.c:1605
 shmem_getpage_gfp+0x891/0x2480 mm/shmem.c:1918
 shmem_getpage mm/shmem.c:161 [inline]
 shmem_write_begin+0xca/0x1b0 mm/shmem.c:2500
 generic_perform_write+0x2cd/0x570 mm/filemap.c:3509
 __generic_file_write_iter+0x23c/0x560 mm/filemap.c:3638
 generic_file_write_iter+0xaf/0x1c0 mm/filemap.c:3670
 call_write_iter include/linux/fs.h:2021 [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
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2ae/0x2d0 mm/page_alloc.c:3336
 free_unref_page_list+0x122/0xb20 mm/page_alloc.c:3443
 release_pages+0xea0/0xef0 mm/swap.c:1103
 __pagevec_release+0x84/0x100 mm/swap.c:1123
 pagevec_release include/linux/pagevec.h:88 [inline]
 shmem_undo_range+0x7d1/0x1a60 mm/shmem.c:965
 shmem_truncate_range mm/shmem.c:1069 [inline]
 shmem_evict_inode+0x215/0x9d0 mm/shmem.c:1169
 evict+0x526/0x9c0 fs/inode.c:612
 iput_final fs/inode.c:1732 [inline]
 iput+0x632/0x7e0 fs/inode.c:1758
 dentry_unlink_inode+0x2ea/0x3d0 fs/dcache.c:378
 __dentry_kill+0x447/0x650 fs/dcache.c:583
 dentry_kill+0xc0/0x2a0
 dput+0x40/0x80 fs/dcache.c:883
 __fput+0x52e/0x7b0 fs/file_table.c:294
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x129/0x190 kernel/task_work.c:189
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop+0xbf/0xd0 kernel/entry/common.c:172

Memory state around the buggy address:
 ffff88812265d680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88812265d700: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88812265d780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88812265d800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88812265d880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs (loop3): Delayed block allocation failed for inode 19 at logical offset 0 with max blocks 16 with error 117
EXT4-fs (loop3): This should not happen!! Data will be lost