================================================================== 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 ffff888120121bbc by task syz-executor.3/386 CPU: 0 PID: 386 Comm: syz-executor.3 Not tainted 5.10.215-syzkaller-1002366-gb58b8f9dad93 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 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:4137 ext4_map_blocks+0xa65/0x1d10 fs/ext4/inode.c:644 mpage_map_one_extent fs/ext4/inode.c:2423 [inline] mpage_map_and_submit_extent fs/ext4/inode.c:2476 [inline] ext4_writepages+0x148b/0x3c00 fs/ext4/inode.c:2844 do_writepages+0x12e/0x270 mm/page-writeback.c:2358 __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:2870 [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+0xb55/0xe70 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+0x61/0xc6 RIP: 0033:0x7f1061234859 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:00007f1060db70c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f1061353f80 RCX: 00007f1061234859 RDX: 000000000208e24b RSI: 0000000020000040 RDI: 0000000000000007 RBP: 00007f1061290ad0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f1061353f80 R15: 00007ffd43943b48 The buggy address belongs to the page: page:ffffea0004804840 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x120121 flags: 0x4000000000000000() raw: 4000000000000000 ffffea0004892208 ffff8881f725ab70 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 0x101cca(GFP_HIGHUSER_MOVABLE|__GFP_WRITE), pid 386, ts 48931879145, free_ts 49241541336 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] __page_cache_alloc include/linux/pagemap.h:290 [inline] pagecache_get_page+0x669/0x950 mm/filemap.c:1848 grab_cache_page_write_begin+0x5d/0xa0 mm/filemap.c:3459 ext4_write_begin+0x29f/0x1730 fs/ext4/inode.c:1178 ext4_da_write_begin+0x49d/0xf60 fs/ext4/inode.c:3004 generic_perform_write+0x2cd/0x570 mm/filemap.c:3509 ext4_buffered_write_iter+0x482/0x610 fs/ext4/file.c:271 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+0xb55/0xe70 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+0x61/0xc6 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+0x7e/0x1c0 mm/page_alloc.c:3391 __put_single_page mm/swap.c:104 [inline] __put_page+0xb1/0xe0 mm/swap.c:135 put_page include/linux/mm.h:1257 [inline] ext4_write_begin+0x12c6/0x1730 fs/ext4/inode.c:1260 ext4_da_write_begin+0x49d/0xf60 fs/ext4/inode.c:3004 generic_perform_write+0x2cd/0x570 mm/filemap.c:3509 ext4_buffered_write_iter+0x482/0x610 fs/ext4/file.c:271 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+0xb55/0xe70 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+0x61/0xc6 Memory state around the buggy address: ffff888120121a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888120121b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888120121b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888120121c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888120121c80: 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