EXT4-fs error (device loop3): ext4_free_blocks:5690: comm syz.3.643: Freeing blocks not in datazone - block = 481, count = 15 EXT4-fs error (device loop3): ext4_free_blocks:5690: comm syz.3.643: Freeing blocks not in datazone - block = 480, count = 16 ================================================================== BUG: KASAN: use-after-free in ext4_ext_rm_leaf fs/ext4/extents.c:2712 [inline] BUG: KASAN: use-after-free in ext4_ext_remove_space+0x231b/0x4570 fs/ext4/extents.c:2934 Read of size 191100 at addr ffff888141fa3448 by task syz.3.643/2906 CPU: 1 PID: 2906 Comm: syz.3.643 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 memmove+0x2d/0x70 mm/kasan/shadow.c:54 ext4_ext_rm_leaf fs/ext4/extents.c:2712 [inline] ext4_ext_remove_space+0x231b/0x4570 fs/ext4/extents.c:2934 ext4_punch_hole+0x6f8/0xad0 fs/ext4/inode.c:4223 ext4_fallocate+0x271/0x1a70 fs/ext4/extents.c:4774 vfs_fallocate+0x4b4/0x590 fs/open.c:310 madvise_remove mm/madvise.c:880 [inline] madvise_vma_behavior mm/madvise.c:904 [inline] madvise_walk_vmas mm/madvise.c:1131 [inline] do_madvise+0x1443/0x1d70 mm/madvise.c:1308 __do_sys_madvise mm/madvise.c:1322 [inline] __se_sys_madvise mm/madvise.c:1320 [inline] __x64_sys_madvise+0xa9/0xc0 mm/madvise.c:1320 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f9cca2b3dd9 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:00007f9cc88a9028 EFLAGS: 00000246 ORIG_RAX: 000000000000001c RAX: ffffffffffffffda RBX: 00007f9cca52d270 RCX: 00007f9cca2b3dd9 RDX: 0000000000000009 RSI: 0000000000600003 RDI: 0000200000000000 RBP: 00007f9cca349d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f9cca52d308 R14: 00007f9cca52d270 R15: 00007ffc3e76b298 The buggy address belongs to the page: page:ffffea000507e8c0 refcount:3 mapcount:0 mapping:ffff8881092fa050 index:0x30 pfn:0x141fa3 aops:def_blk_aops ino:0 flags: 0x4000000000022036(referenced|uptodate|lru|active|private|mappedtodisk) raw: 4000000000022036 ffffea0004b4f308 ffff888128e3d030 ffff8881092fa050 raw: 0000000000000030 ffff88812dfb5c78 00000003ffffffff ffff888128e34000 page dumped because: kasan: bad access detected page->mem_cgroup:ffff888128e34000 page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x108c48(GFP_NOFS|__GFP_NOFAIL|__GFP_HARDWALL|__GFP_MOVABLE), pid 2899, ts 166668696216, free_ts 166663079750 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x223b/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x290/0x620 mm/page_alloc.c:5384 __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] __page_cache_alloc include/linux/pagemap.h:290 [inline] pagecache_get_page+0x63e/0x930 mm/filemap.c:1848 find_or_create_page include/linux/pagemap.h:402 [inline] grow_dev_page fs/buffer.c:976 [inline] grow_buffers fs/buffer.c:1045 [inline] __getblk_slow fs/buffer.c:1072 [inline] __getblk_gfp+0x212/0x780 fs/buffer.c:1370 sb_getblk_gfp include/linux/buffer_head.h:368 [inline] ext4_ext_grow_indepth fs/ext4/extents.c:1327 [inline] ext4_ext_create_new_leaf fs/ext4/extents.c:1426 [inline] ext4_ext_insert_extent+0x10a2/0x45d0 fs/ext4/extents.c:2098 ext4_ext_map_blocks+0x1709/0x5e00 fs/ext4/extents.c:4372 ext4_map_blocks+0x985/0x1bd0 fs/ext4/inode.c:674 _ext4_get_block+0x1d1/0x4e0 fs/ext4/inode.c:817 ext4_get_block+0x39/0x50 fs/ext4/inode.c:834 ext4_block_write_begin+0x573/0x1340 fs/ext4/inode.c:1101 ext4_write_begin+0x67e/0x1690 fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x478/0xf10 fs/ext4/inode.c:3033 generic_perform_write+0x2ce/0x540 mm/filemap.c:3509 ext4_buffered_write_iter+0x4b8/0x640 fs/ext4/file.c:271 ext4_file_write_iter+0x53f/0x1980 fs/ext4/file.c:-1 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+0x2b7/0x2d0 mm/page_alloc.c:3336 free_unref_page_list+0x129/0x9c0 mm/page_alloc.c:3443 release_pages+0xe52/0xea0 mm/swap.c:1103 __pagevec_release+0x71/0xe0 mm/swap.c:1123 pagevec_release include/linux/pagevec.h:88 [inline] shmem_undo_range+0x74a/0x1810 mm/shmem.c:965 shmem_truncate_range mm/shmem.c:1069 [inline] shmem_evict_inode+0x210/0xa00 mm/shmem.c:1169 evict+0x4ae/0x930 fs/inode.c:612 iput_final fs/inode.c:1736 [inline] iput+0x638/0x7c0 fs/inode.c:1762 dentry_unlink_inode+0x2cf/0x380 fs/dcache.c:378 __dentry_kill+0x44f/0x650 fs/dcache.c:583 dentry_kill+0xc0/0x2a0 fs/dcache.c:-1 dput+0x42/0x80 fs/dcache.c:883 __fput+0x4fe/0x770 fs/file_table.c:294 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa90/0x2500 kernel/exit.c:872 Memory state around the buggy address: ffff888141fabf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888141fabf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888141fac000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888141fac080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888141fac100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================