EXT4-fs (loop2): mounted filesystem without journal. Quota mode: none. EXT4-fs error (device loop2): ext4_validate_block_bitmap:438: comm syz.2.17: bg 0: block 465: padding at end of block bitmap is not set EXT4-fs (loop2): Remounting filesystem read-only ================================================================== BUG: KASAN: use-after-free in ext4_read_inline_data fs/ext4/inline.c:210 [inline] BUG: KASAN: use-after-free in ext4_inlinedir_to_tree+0x50c/0xff0 fs/ext4/inline.c:1412 Read of size 52 at addr ffff888115645b97 by task syz.2.17/375 CPU: 1 PID: 375 Comm: syz.2.17 Not tainted 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:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x71/0x200 mm/kasan/report.c:316 print_report+0x4a/0x60 mm/kasan/report.c:420 kasan_report+0x122/0x150 mm/kasan/report.c:524 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:210 [inline] ext4_inlinedir_to_tree+0x50c/0xff0 fs/ext4/inline.c:1412 ext4_htree_fill_tree+0x508/0x1160 fs/ext4/namei.c:1211 ext4_dx_readdir fs/ext4/dir.c:608 [inline] ext4_readdir+0x2f80/0x3e10 fs/ext4/dir.c:145 iterate_dir+0x271/0x610 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 x64_sys_call+0x212/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:79 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fb0fc99ce59 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:00007ffe20062fc8 EFLAGS: 00000246 ORIG_RAX: 000000000000004e RAX: ffffffffffffffda RBX: 00007fb0fcc15fa0 RCX: 00007fb0fc99ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 00007fb0fca32d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb0fcc15fac R14: 00007fb0fcc15fa0 R15: 00007fb0fcc15fa0 The buggy address belongs to the physical page: page:ffffea0004559140 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115645 flags: 0x4000000000000000(zone=1) raw: 4000000000000000 dead000000000100 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as freed page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 362, tgid 362 (syz-executor), ts 22913277491, free_ts 22990559921 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2672 prep_new_page+0x1c/0x110 mm/page_alloc.c:2679 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4585 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5929 vm_area_alloc_pages mm/vmalloc.c:-1 [inline] __vmalloc_area_node mm/vmalloc.c:3084 [inline] __vmalloc_node_range+0x8bf/0x1430 mm/vmalloc.c:3256 vmalloc_user+0x73/0x80 mm/vmalloc.c:3410 kcov_ioctl+0x57/0x620 kernel/kcov.c:713 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0x12f/0x1b0 fs/ioctl.c:856 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:856 x64_sys_call+0x58b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1580 [inline] free_pcp_prepare mm/page_alloc.c:1654 [inline] free_unref_page_prepare+0x7f8/0x800 mm/page_alloc.c:3620 free_unref_page+0x95/0x540 mm/page_alloc.c:3718 free_the_page mm/page_alloc.c:863 [inline] __free_pages+0x67/0x100 mm/page_alloc.c:6019 __vunmap+0x9c0/0xb80 mm/vmalloc.c:2739 __vfree mm/vmalloc.c:2788 [inline] vfree+0x61/0x90 mm/vmalloc.c:2819 kcov_put kernel/kcov.c:437 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:533 __fput+0x1fc/0x8f0 fs/file_table.c:320 ____fput+0x15/0x20 fs/file_table.c:348 task_work_run+0x1e1/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa35/0x2660 kernel/exit.c:886 do_group_exit+0x225/0x2e0 kernel/exit.c:1029 get_signal+0x13b5/0x1520 kernel/signal.c:2891 arch_do_signal_or_restart+0xd1/0x1140 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 Memory state around the buggy address: ffff888115645a80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888115645b00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff888115645b80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff888115645c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888115645c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== EXT4-fs error (device loop2): ext4_inlinedir_to_tree:1450: inode #12: block 7: comm syz.2.17: path /0/file1/file0: bad entry in directory: rec_len % 4 != 0 - offset=35110, inode=3517778242, rec_len=35106, size=112 fake=0 EXT4-fs (loop2): Remounting filesystem read-only