EXT4-fs (loop2): mounted filesystem without journal. Opts: errors=remount-ro,
EXT4-fs error (device loop2): ext4_validate_block_bitmap:438: comm syz.2.20: 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:209 [inline]
BUG: KASAN: use-after-free in ext4_inlinedir_to_tree+0x5f6/0xfd0 fs/ext4/inline.c:1419
Read of size 52 at addr ffff88812351a05f by task syz.2.20/547

CPU: 0 PID: 547 Comm: syz.2.20 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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
 memcpy+0x2d/0x70 mm/kasan/shadow.c:65
 ext4_read_inline_data fs/ext4/inline.c:209 [inline]
 ext4_inlinedir_to_tree+0x5f6/0xfd0 fs/ext4/inline.c:1419
 ext4_htree_fill_tree+0x508/0x1160 fs/ext4/namei.c:1186
 ext4_dx_readdir fs/ext4/dir.c:601 [inline]
 ext4_readdir+0x2c49/0x3ab0 fs/ext4/dir.c:145
 iterate_dir+0x260/0x570 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: 0033:0x7fd46a1d9cb9
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:00007fd46a03e028 EFLAGS: 00000246 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007fd46a454fa0 RCX: 00007fd46a1d9cb9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007fd46a247bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd46a455038 R14: 00007fd46a454fa0 R15: 00007fff04549578

The buggy address belongs to the page:
page:ffffea00048d4680 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12351a
flags: 0x4000000000000000()
raw: 4000000000000000 ffffea00048d46c8 ffffea00048d4648 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 0x8100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO|0x8000000), pid 436, ts 46140326838, free_ts 46140841489
 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]
 do_anonymous_page mm/memory.c:3963 [inline]
 handle_pte_fault+0x1719/0x3750 mm/memory.c:4786
 __handle_mm_fault mm/memory.c:4944 [inline]
 handle_mm_fault+0xf81/0x1710 mm/memory.c:5358
 do_user_addr_fault+0x5a8/0xc90 arch/x86/mm/fault.c:1362
 handle_page_fault arch/x86/mm/fault.c:1428 [inline]
 exc_page_fault+0x5a/0xc0 arch/x86/mm/fault.c:1484
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:571
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
 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:356
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x17e/0x310 mm/mmu_gather.c:326
 unmap_region+0x355/0x3c0 mm/mmap.c:2811
 __do_munmap+0x63c/0x850 mm/mmap.c:3041
 __vm_munmap mm/mmap.c:3094 [inline]
 __do_sys_munmap mm/mmap.c:3120 [inline]
 __se_sys_munmap+0x130/0x1c0 mm/mmap.c:3116
 __x64_sys_munmap+0x5b/0x70 mm/mmap.c:3116
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff888123519f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888123519f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88812351a000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                    ^
 ffff88812351a080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88812351a100: 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:1457: inode #12: block 7: comm syz.2.20: path /3/file1/file0: bad entry in directory: rec_len % 4 != 0 - offset=39503, inode=3885038053, rec_len=39499, size=112 fake=0