EXT4-fs error (device loop0): ext4_mkdir:3035: inode #12: comm syz.0.76: mark_inode_dirty error ================================================================== BUG: KASAN: use-after-free in ext4_read_inline_data fs/ext4/inline.c:209 [inline] BUG: KASAN: use-after-free in ext4_read_inline_dir+0x414/0xd00 fs/ext4/inline.c:1541 Read of size 68 at addr ffff88812a22f9cc by task syz.0.76/647 CPU: 0 PID: 647 Comm: syz.0.76 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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+0x100/0x140 mm/kasan/report.c:452 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189 memcpy+0x2d/0x70 mm/kasan/shadow.c:65 ext4_read_inline_data fs/ext4/inline.c:209 [inline] ext4_read_inline_dir+0x414/0xd00 fs/ext4/inline.c:1541 ext4_readdir+0x3a0/0x3a80 fs/ext4/dir.c:161 iterate_dir+0x25c/0x560 fs/readdir.c:-1 __do_sys_getdents fs/readdir.c:286 [inline] __se_sys_getdents+0xf2/0x250 fs/readdir.c:271 __x64_sys_getdents+0x7b/0x90 fs/readdir.c:271 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f235bddd159 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:00007f235a836028 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007f235c064fa0 RCX: 00007f235bddd159 RDX: 00000000000000b8 RSI: 0000200000001fc0 RDI: 0000000000000009 RBP: 00007f235be7406b R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f235c065038 R14: 00007f235c064fa0 R15: 00007ffc699d37e8 The buggy address belongs to the page: page:ffffea0004a88bc0 refcount:1 mapcount:0 mapping:ffff88811d03ed70 index:0x51f pfn:0x12a22f aops:shmem_aops ino:429 dentry name:"memfd:syzkaller" flags: 0x400000000008001e(referenced|uptodate|dirty|lru|swapbacked) raw: 400000000008001e ffffea0004a88b88 ffffea0004c5c408 ffff88811d03ed70 raw: 000000000000051f 0000000000000000 00000001ffffffff ffff88810e996000 page dumped because: kasan: bad access detected page->mem_cgroup:ffff88810e996000 page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x100cca(GFP_HIGHUSER_MOVABLE), pid 654, ts 37003029612, free_ts 36661669864 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x176/0x190 mm/page_alloc.c:2462 get_page_from_freelist+0x225f/0x23f0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x29a/0x640 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] shmem_alloc_page+0x1fd/0x380 mm/shmem.c:1580 shmem_alloc_and_acct_page+0x3d3/0x840 mm/shmem.c:1605 shmem_getpage_gfp+0x785/0x20f0 mm/shmem.c:1918 shmem_getpage mm/shmem.c:161 [inline] shmem_write_begin+0xce/0x1b0 mm/shmem.c:2497 generic_perform_write+0x2ce/0x540 mm/filemap.c:3509 __generic_file_write_iter+0x24b/0x480 mm/filemap.c:3638 generic_file_write_iter+0xa9/0x1d0 mm/filemap.c:3670 call_write_iter include/linux/fs.h:2072 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0x770/0xd70 fs/read_write.c:605 ksys_write+0x14a/0x260 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+0x31/0x40 arch/x86/entry/common.c:46 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+0x2b7/0x2d0 mm/page_alloc.c:3336 free_unref_page_list+0x129/0x9c0 mm/page_alloc.c:3443 release_pages+0xe41/0xe90 mm/swap.c:1103 __pagevec_release+0x71/0xe0 mm/swap.c:1123 pagevec_release include/linux/pagevec.h:88 [inline] shmem_undo_range+0x741/0x1740 mm/shmem.c:965 shmem_truncate_range mm/shmem.c:1069 [inline] shmem_evict_inode+0x1dc/0x970 mm/shmem.c:1169 evict+0x4a9/0x940 fs/inode.c:612 iput_final fs/inode.c:1736 [inline] iput+0x654/0x7e0 fs/inode.c:1762 dentry_unlink_inode+0x2d5/0x390 fs/dcache.c:378 __dentry_kill+0x45b/0x660 fs/dcache.c:583 dentry_kill+0xc0/0x2a0 fs/dcache.c:-1 dput+0x42/0x80 fs/dcache.c:883 __fput+0x4bd/0x730 fs/file_table.c:294 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x127/0x190 kernel/task_work.c:189 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172 Memory state around the buggy address: ffff88812a22f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812a22f900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88812a22f980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88812a22fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812a22fa80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== EXT4-fs error (device loop0): ext4_read_inline_dir:1622: inode #12: block 5: comm syz.0.76: path /15/file0/file0: bad entry in directory: directory entry overrun - offset=24, inode=2829230728, rec_len=11816, size=148 fake=0 EXT4-fs error (device loop0) in ext4_do_update_inode:5362: error 27 EXT4-fs error (device loop0): ext4_dirty_inode:6181: inode #12: comm syz.0.76: mark_inode_dirty error