==================================================================
BUG: KASAN: use-after-free in ext4_htree_fill_tree+0x10f0/0x1160 fs/ext4/namei.c:1246
Read of size 1 at addr ffff88811ae21d1b by task syz-executor/466

CPU: 0 PID: 466 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 __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
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:348
 ext4_htree_fill_tree+0x10f0/0x1160 fs/ext4/namei.c:1246
 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_getdents64 fs/readdir.c:369 [inline]
 __se_sys_getdents64+0xf2/0x250 fs/readdir.c:354
 __x64_sys_getdents64+0x7b/0x90 fs/readdir.c:354
 x64_sys_call+0x15c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218
 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: 0033:0x7f908b5b8d73
Code: c7 c0 e8 ff ff ff 64 c7 00 16 00 00 00 31 c0 eb 9e e8 81 9b fd ff 90 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 c7 c2 e8 ff ff ff f7 d8
RSP: 002b:00007ffe22b528d8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 000055555f567910 RCX: 00007f908b5b8d73
RDX: 0000000000008000 RSI: 000055555f567940 RDI: 0000000000000005
RBP: 000055555f567940 R08: 0000000000028701 R09: 0000000000000001
R10: 00007f908b763ca0 R11: 0000000000000293 R12: 000055555f567914
R13: ffffffffffffffe8 R14: 0000000000000010 R15: 0000000000000001
 </TASK>

Allocated by task 467:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc+0x16e/0x330 mm/slub.c:3408
 getname_flags+0xb9/0x500 fs/namei.c:139
 getname+0x19/0x20 fs/namei.c:218
 __do_sys_execve fs/exec.c:2132 [inline]
 __se_sys_execve fs/exec.c:2127 [inline]
 __x64_sys_execve+0x78/0xb0 fs/exec.c:2127
 x64_sys_call+0x98/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:60
 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

Freed by task 467:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 kmem_cache_free+0x12d/0x300 mm/slub.c:3737
 putname+0x111/0x160 fs/namei.c:272
 do_execveat_common+0x928/0xa70 fs/exec.c:1987
 do_execve fs/exec.c:2056 [inline]
 __do_sys_execve fs/exec.c:2132 [inline]
 __se_sys_execve fs/exec.c:2127 [inline]
 __x64_sys_execve+0x92/0xb0 fs/exec.c:2127
 x64_sys_call+0x98/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:60
 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

The buggy address belongs to the object at ffff88811ae21100
 which belongs to the cache names_cache of size 4096
The buggy address is located 3099 bytes inside of
 4096-byte region [ffff88811ae21100, ffff88811ae22100)

The buggy address belongs to the physical page:
page:ffffea00046b8800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11ae20
head:ffffea00046b8800 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff8881001eca80
raw: 0000000000000000 0000000000070007 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 107, tgid 107 (udevd), ts 6973040845, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650
 get_page_from_freelist+0x2d12/0x2d80 mm/page_alloc.c:4554
 __alloc_pages+0x1d9/0x480 mm/page_alloc.c:5868
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3d0 mm/slub.c:2020
 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc+0x1b0/0x330 mm/slub.c:3408
 getname_flags+0xb9/0x500 fs/namei.c:139
 getname+0x19/0x20 fs/namei.c:218
 do_sys_openat2+0xeb/0x810 fs/open.c:1337
 do_sys_open fs/open.c:1359 [inline]
 __do_sys_openat fs/open.c:1375 [inline]
 __se_sys_openat fs/open.c:1370 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1370
 x64_sys_call+0x783/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:258
 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_owner free stack trace missing

Memory state around the buggy address:
 ffff88811ae21c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811ae21c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811ae21d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff88811ae21d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811ae21e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop0): __ext4_get_inode_loc:4515: comm syz-executor: Invalid inode table block 14875662660405297151 in block_group 0
EXT4-fs error (device loop0) in ext4_reserve_inode_write:5930: Corrupt filesystem
EXT4-fs error (device loop0): ext4_dirty_inode:6134: inode #2: comm syz-executor: mark_inode_dirty error
EXT4-fs (loop0): unmounting filesystem.