==================================================================
BUG: KASAN: use-after-free in dx_insert_block fs/ext4/namei.c:1387 [inline]
BUG: KASAN: use-after-free in do_split+0x1f31/0x24e0 fs/ext4/namei.c:2080
Read of size 157024 at addr ffff8881338e9028 by task syz.5.410/1766
CPU: 0 PID: 1766 Comm: syz.5.410 Not tainted 5.15.178-syzkaller-1079147-g7d1f9b5c2ff5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x151/0x1c0 lib/dump_stack.c:106
print_address_description+0x87/0x3b0 mm/kasan/report.c:248
__kasan_report mm/kasan/report.c:427 [inline]
kasan_report+0x179/0x1c0 mm/kasan/report.c:444
kasan_check_range+0x293/0x2a0 mm/kasan/generic.c:189
memmove+0x2d/0x70 mm/kasan/shadow.c:54
dx_insert_block fs/ext4/namei.c:1387 [inline]
do_split+0x1f31/0x24e0 fs/ext4/namei.c:2080
make_indexed_dir+0xeb7/0x15a0 fs/ext4/namei.c:2392
ext4_add_entry+0xde2/0x12b0 fs/ext4/namei.c:2504
__ext4_link+0x4e9/0x790 fs/ext4/namei.c:3536
ext4_link+0x1f3/0x290 fs/ext4/namei.c:3577
vfs_link+0x645/0x7f0 fs/namei.c:4557
do_linkat+0x34d/0x9f0 fs/namei.c:4628
__do_sys_link fs/namei.c:4662 [inline]
__se_sys_link fs/namei.c:4660 [inline]
__x64_sys_link+0x86/0x90 fs/namei.c:4660
x64_sys_call+0x282/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:87
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa634ef8169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fa63496a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000056
RAX: ffffffffffffffda RBX: 00007fa635110fa0 RCX: 00007fa634ef8169
RDX: 0000000000000000 RSI: 0000400000000bc0 RDI: 0000400000001240
RBP: 00007fa634f792a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fa635110fa0 R15: 00007ffd89d0c538
</TASK>
The buggy address belongs to the page:
page:ffffea0004ce3a40 refcount:3 mapcount:1 mapping:ffff888109338d98 index:0x1 pfn:0x1338e9
memcg:ffff88810ed6c000
aops:def_blk_aops ino:700005
flags: 0x400000000032201e(referenced|uptodate|dirty|lru|private|mappedtodisk|unevictable|mlocked|zone=1)
raw: 400000000032201e ffffea0004b11a48 ffffea00046e8208 ffff888109338d98
raw: 0000000000000001 ffff88810c841c78 0000000300000000 ffff88810ed6c000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x108c48(GFP_NOFS|__GFP_NOFAIL|__GFP_HARDWALL|__GFP_MOVABLE), pid 1766, ts 174141497889, free_ts 174085405231
set_page_owner include/linux/page_owner.h:33 [inline]
post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2605
prep_new_page+0x1b/0x110 mm/page_alloc.c:2611
get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4485
__alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5780
__alloc_pages_node include/linux/gfp.h:591 [inline]
alloc_pages_node include/linux/gfp.h:605 [inline]
alloc_pages include/linux/gfp.h:618 [inline]
__page_cache_alloc include/linux/pagemap.h:305 [inline]
pagecache_get_page+0xb18/0xeb0 mm/filemap.c:1946
find_or_create_page include/linux/pagemap.h:418 [inline]
grow_dev_page fs/buffer.c:949 [inline]
grow_buffers fs/buffer.c:1014 [inline]
__getblk_slow fs/buffer.c:1041 [inline]
__getblk_gfp+0x21e/0x7c0 fs/buffer.c:1336
sb_getblk include/linux/buffer_head.h:361 [inline]
ext4_getblk+0x259/0x700 fs/ext4/inode.c:877
ext4_bread_batch+0x67/0x4c0 fs/ext4/inode.c:944
__ext4_find_entry+0xfbe/0x1af0 fs/ext4/namei.c:1671
ext4_lookup_entry fs/ext4/namei.c:1774 [inline]
ext4_lookup+0x3c6/0xaa0 fs/ext4/namei.c:1842
lookup_open fs/namei.c:3440 [inline]
open_last_lookups fs/namei.c:3532 [inline]
path_openat+0x1194/0x2f40 fs/namei.c:3739
do_filp_open+0x21c/0x460 fs/namei.c:3769
do_sys_openat2+0x13f/0x820 fs/open.c:1234
do_sys_open fs/open.c:1250 [inline]
__do_sys_creat fs/open.c:1326 [inline]
__se_sys_creat fs/open.c:1320 [inline]
__x64_sys_creat+0x11f/0x160 fs/open.c:1320
x64_sys_call+0x27b/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:86
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
page last free stack trace:
reset_page_owner include/linux/page_owner.h:26 [inline]
free_pages_prepare mm/page_alloc.c:1472 [inline]
free_pcp_prepare mm/page_alloc.c:1544 [inline]
free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3534
free_unref_page_list+0x14b/0xa60 mm/page_alloc.c:3671
release_pages+0x1310/0x1370 mm/swap.c:1009
__pagevec_release+0x84/0x100 mm/swap.c:1029
pagevec_release include/linux/pagevec.h:81 [inline]
shmem_undo_range+0x604/0x1560 mm/shmem.c:965
shmem_truncate_range mm/shmem.c:1064 [inline]
shmem_evict_inode+0x215/0x9d0 mm/shmem.c:1146
evict+0x529/0x930 fs/inode.c:622
iput_final fs/inode.c:1744 [inline]
iput+0x63b/0x7e0 fs/inode.c:1770
dentry_unlink_inode+0x34e/0x430 fs/dcache.c:380
__dentry_kill+0x447/0x660 fs/dcache.c:586
dentry_kill+0xc0/0x2a0
dput+0x45/0x80 fs/dcache.c:893
do_renameat2+0xc5b/0x1480 fs/namei.c:4987
__do_sys_rename fs/namei.c:5031 [inline]
__se_sys_rename fs/namei.c:5029 [inline]
__x64_sys_rename+0x86/0x90 fs/namei.c:5029
x64_sys_call+0x266/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:83
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
Memory state around the buggy address:
ffff8881338eaf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8881338eaf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881338eb000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff8881338eb080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff8881338eb100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs error (device loop5): ext4_dx_csum_set:531: inode #2: comm syz.5.410: dir seems corrupt? Run e2fsck -D.