[Android 5.15] KASAN: use-after-free Read in ext4_read_inline_dir

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 19092c8155b4 Merge 5.15.175 into android13-5.15-lts
git tree: android13-5.15-lts
console+strace: https://syzkaller.appspot.com/x/log.txt?x=105ededf980000
kernel config: https://syzkaller.appspot.com/x/.config?x=8724df306b02dc21
dashboard link: https://syzkaller.appspot.com/bug?extid=26c4a8cab92d0cda3e3b
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11789c18580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16b605c4580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7389fdaea007/disk-19092c81.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e59c2edaa05f/vmlinux-19092c81.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a769778499a3/bzImage-19092c81.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/df094f7bff95/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+26c4a8...@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in ext4_read_inline_data fs/ext4/inline.c:210 [inline]
BUG: KASAN: use-after-free in ext4_read_inline_dir+0x525/0xee0 fs/ext4/inline.c:1533
Read of size 68 at addr ffff88811c906d05 by task syz-executor275/304

CPU: 0 PID: 304 Comm: syz-executor275 Not tainted 5.15.175-syzkaller-00803-g19092c8155b4 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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
memcpy+0x2d/0x70 mm/kasan/shadow.c:65
ext4_read_inline_data fs/ext4/inline.c:210 [inline]
ext4_read_inline_dir+0x525/0xee0 fs/ext4/inline.c:1533
ext4_readdir+0x410/0x3960 fs/ext4/dir.c:158
iterate_dir+0x265/0x600
__do_sys_getdents64 fs/readdir.c:369 [inline]
__se_sys_getdents64+0x1c1/0x460 fs/readdir.c:354
__x64_sys_getdents64+0x7b/0x90 fs/readdir.c:354
x64_sys_call+0x5ae/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:218
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: 0033:0x7f97668eb133
Code: c1 66 0f 1f 44 00 00 48 83 c4 08 48 89 ef 5b 5d e9 62 47 fb ff 66 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 b8 ff ff ff f7 d8
RSP: 002b:00007ffedbbd5498 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 0000555584d0e770 RCX: 00007f97668eb133
RDX: 0000000000008000 RSI: 0000555584d0e770 RDI: 0000000000000005
RBP: 0000555584d0e744 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000293 R12: ffffffffffffffb8
R13: 0000000000000016 R14: 0000555584d0e740 R15: 00007ffedbbd8800
</TASK>

The buggy address belongs to the page:
page:ffffea0004724180 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x11c906
flags: 0x4000000000000000(zone=1)
raw: 4000000000000000 ffffea00047241c8 ffffea0004724148 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 0x100dca(GFP_HIGHUSER_MOVABLE|__GFP_ZERO), pid 285, ts 25091530778, free_ts 25103826626
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]
do_anonymous_page mm/memory.c:4066 [inline]
handle_pte_fault+0xe7e/0x25c0 mm/memory.c:4903
do_handle_mm_fault+0x20bc/0x2400 mm/memory.c:5327
handle_mm_fault include/linux/mm.h:1836 [inline]
do_user_addr_fault arch/x86/mm/fault.c:1418 [inline]
handle_page_fault arch/x86/mm/fault.c:1509 [inline]
exc_page_fault+0x3b5/0x7f0 arch/x86/mm/fault.c:1565
asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:606
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
free_pages_and_swap_cache+0x8a/0xa0 mm/swap_state.c:320
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+0x177/0x320 mm/mmu_gather.c:338
unmap_region+0x304/0x350 mm/mmap.c:2680
__do_munmap+0x13e4/0x19d0 mm/mmap.c:2913
__vm_munmap+0x166/0x2a0 mm/mmap.c:2966
__do_sys_munmap mm/mmap.c:2992 [inline]
__se_sys_munmap mm/mmap.c:2988 [inline]
__x64_sys_munmap+0x6b/0x80 mm/mmap.c:2988
x64_sys_call+0x75/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12
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

Memory state around the buggy address:
ffff88811c906c00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88811c906c80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88811c906d00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88811c906d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88811c906e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
EXT4-fs error (device loop0): ext4_read_inline_dir:1614: inode #12: block 5: comm syz-executor275: path /root/syzkaller.0iQVEA/0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0
EXT4-fs error (device loop0): ext4_read_inline_dir:1614: inode #12: block 5: comm syz-executor275: path /root/syzkaller.0iQVEA/0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0
EXT4-fs error (device loop0): empty_inline_dir:1869: inode #12: block 5: comm syz-executor275: bad entry in directory: rec_len % 4 != 0 - offset=4, inode=1633771873, rec_len=24929, size=60 fake=0
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs error (device loop0): ext4_read_inline_dir:1614: inode #12: block 5: comm syz-executor275: path /root/syzkaller.0iQVEA/0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0
EXT4-fs error (device loop0): ext4_read_inline_dir:1614: inode #12: block 5: comm syz-executor275: path /root/syzkaller.0iQVEA/0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0
EXT4-fs error (device loop0): empty_inline_dir:1869: inode #12: block 5: comm syz-executor275: bad entry in directory: rec_len % 4 != 0 - offset=4, inode=1633771873, rec_len=24929, size=60 fake=0
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs error (device loop0): ext4_read_inline_dir:1614: inode #12: block 5: comm syz-executor275: path /root/syzkaller.0iQVEA/0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0
EXT4-fs error (device loop0): ext4_read_inline_dir:1614: inode #12: block 5: comm syz-executor275: path /root/syzkaller.0iQVEA/0/file0/file0: bad entry in directory: rec_len % 4 != 0 - offset=24, inode=1633771873, rec_len=24929, size=148 fake=0
EXT4-fs error (device loop0): empty_inline_dir:1869: inode #12: block 5: comm syz-executor275: bad entry in directory: rec_len % 4 != 0 - offset=4, inode=1633771873, rec_len=24929, size=60 fake=0
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60
EXT4-fs warning (device loop0): empty_inline_dir:1876: bad inline directory (dir #12) - inode 1633771873, rec_len 24929, name_len 97inline size 60


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