EXT4-fs (loop5): failed to convert unwritten extents to written extents -- potential data loss! (inode 19, error -117) ================================================================== BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:827 [inline] BUG: KASAN: use-after-free in ext4_find_extent+0xbab/0xdb0 fs/ext4/extents.c:946 Read of size 4 at addr ffff888124112a58 by task kworker/u4:5/393 CPU: 0 PID: 393 Comm: kworker/u4:5 Not tainted 5.15.130-syzkaller-1068695-g1317bd27a72f #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106 print_address_description+0x87/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:444 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_ext_binsearch fs/ext4/extents.c:827 [inline] ext4_find_extent+0xbab/0xdb0 fs/ext4/extents.c:946 ext4_ext_map_blocks+0x254/0x7250 fs/ext4/extents.c:4103 ext4_map_blocks+0xaa7/0x1e00 fs/ext4/inode.c:646 ext4_convert_unwritten_extents+0x2e0/0x6c0 fs/ext4/extents.c:4815 ext4_convert_unwritten_io_end_vec+0x104/0x180 fs/ext4/extents.c:4854 ext4_end_io_end fs/ext4/page-io.c:186 [inline] ext4_do_flush_completed_IO fs/ext4/page-io.c:259 [inline] ext4_end_io_rsv_work+0x358/0x690 fs/ext4/page-io.c:273 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2317 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2464 kthread+0x421/0x510 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the page: page:ffffea0004904480 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x124112 flags: 0x4000000000000000(zone=1) raw: 4000000000000000 ffffea00049044c8 ffffea0004904448 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 438, ts 43650476484, free_ts 44242245305 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2602 prep_new_page+0x1b/0x110 mm/page_alloc.c:2608 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4482 __alloc_pages+0x206/0x5e0 mm/page_alloc.c:5773 __alloc_pages_node include/linux/gfp.h:591 [inline] alloc_pages_node include/linux/gfp.h:605 [inline] alloc_pages include/linux/gfp.h:618 [inline] shmem_alloc_page mm/shmem.c:1587 [inline] shmem_alloc_and_acct_page+0x4bd/0xa80 mm/shmem.c:1612 shmem_getpage_gfp+0x1388/0x23c0 mm/shmem.c:1907 shmem_getpage mm/shmem.c:152 [inline] shmem_write_begin+0xca/0x1b0 mm/shmem.c:2478 generic_perform_write+0x2bc/0x5a0 mm/filemap.c:3833 __generic_file_write_iter+0x25b/0x4b0 mm/filemap.c:3960 generic_file_write_iter+0xaf/0x1c0 mm/filemap.c:3992 call_write_iter include/linux/fs.h:2159 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0xd5d/0x1110 fs/read_write.c:594 ksys_write+0x199/0x2c0 fs/read_write.c:647 __do_sys_write fs/read_write.c:659 [inline] __se_sys_write fs/read_write.c:656 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:656 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1469 [inline] free_pcp_prepare mm/page_alloc.c:1541 [inline] free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3531 free_unref_page_list+0x14b/0xa60 mm/page_alloc.c:3668 release_pages+0x1310/0x1370 mm/swap.c:1009 __pagevec_release+0x84/0x100 mm/swap.c:1029 pagevec_release include/linux/pagevec.h:81 [inline] shmem_undo_range+0x604/0x1560 mm/shmem.c:965 shmem_truncate_range mm/shmem.c:1064 [inline] shmem_evict_inode+0x215/0x9d0 mm/shmem.c:1146 evict+0x2a3/0x630 fs/inode.c:587 iput_final fs/inode.c:1705 [inline] iput+0x63b/0x7e0 fs/inode.c:1731 dentry_unlink_inode+0x34f/0x440 fs/dcache.c:376 __dentry_kill+0x447/0x660 fs/dcache.c:582 dentry_kill+0xc0/0x2a0 dput+0x165/0x320 fs/dcache.c:888 __fput+0x662/0x910 fs/file_table.c:288 ____fput+0x15/0x20 fs/file_table.c:308 task_work_run+0x129/0x190 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0xc4/0xe0 kernel/entry/common.c:175 Memory state around the buggy address: ffff888124112900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888124112980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888124112a00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888124112a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888124112b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== EXT4-fs error (device loop5): ext4_map_blocks:716: inode #19: block 3393138700: comm kworker/u4:5: lblock 12 mapped to illegal pblock 3393138700 (length 1) EXT4-fs warning (device loop5): ext4_convert_unwritten_extents:4822: inode #19: block 12: len 1: ext4_ext_map_blocks returned -117 EXT4-fs (loop5): failed to convert unwritten extents to written extents -- potential data loss! (inode 19, error -117) EXT4-fs warning (device loop5): ext4_convert_unwritten_extents:4822: inode #19: block 13: len 1: ext4_ext_map_blocks returned -117 EXT4-fs (loop5): failed to convert unwritten extents to written extents -- potential data loss! (inode 19, error -117)