[v6.1] KASAN: use-after-free Read in ocfs2_listxattr

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: f6e38ae624cf Linux 6.1.158
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1011c512580000
kernel config: https://syzkaller.appspot.com/x/.config?x=68aa5a3af1cb953a
dashboard link: https://syzkaller.appspot.com/bug?extid=55a6d34a3a95c58633df
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c1bd671a9def/disk-f6e38ae6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fa0af998ea40/vmlinux-f6e38ae6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e5512d873524/Image-f6e38ae6.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+55a6d3...@syzkaller.appspotmail.com

ocfs2: Mounting device (7,2) on (node local, slot 0) with ordered data mode.
capability: warning: `syz.2.20' uses deprecated v2 capabilities in a way that may be insecure
==================================================================
BUG: KASAN: use-after-free in ocfs2_xattr_get_type fs/ocfs2/ocfs2_fs.h:1113 [inline]
BUG: KASAN: use-after-free in ocfs2_xattr_list_entries fs/ocfs2/xattr.c:938 [inline]
BUG: KASAN: use-after-free in ocfs2_xattr_ibody_list fs/ocfs2/xattr.c:986 [inline]
BUG: KASAN: use-after-free in ocfs2_listxattr+0x408/0xa74 fs/ocfs2/xattr.c:1048
Read of size 1 at addr ffff0000e51c0007 by task syz.2.20/4517

CPU: 0 PID: 4517 Comm: syz.2.20 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
__dump_stack+0x30/0x40 lib/dump_stack.c:88
dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
print_address_description+0x88/0x218 mm/kasan/report.c:316
print_report+0x50/0x68 mm/kasan/report.c:420
kasan_report+0xa8/0x100 mm/kasan/report.c:524
__asan_report_load1_noabort+0x2c/0x38 mm/kasan/report_generic.c:348
ocfs2_xattr_get_type fs/ocfs2/ocfs2_fs.h:1113 [inline]
ocfs2_xattr_list_entries fs/ocfs2/xattr.c:938 [inline]
ocfs2_xattr_ibody_list fs/ocfs2/xattr.c:986 [inline]
ocfs2_listxattr+0x408/0xa74 fs/ocfs2/xattr.c:1048
vfs_listxattr fs/xattr.c:457 [inline]
listxattr+0x29c/0x3cc fs/xattr.c:804
path_listxattr+0xdc/0x1b4 fs/xattr.c:828
__do_sys_listxattr fs/xattr.c:840 [inline]
__se_sys_listxattr fs/xattr.c:837 [inline]
__arm64_sys_listxattr+0x80/0x94 fs/xattr.c:837
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the physical page:
page:0000000052501771 refcount:0 mapcount:-128 mapping:0000000000000000 index:0x1 pfn:0x1251c0
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003949008 fffffc000394e008 0000000000000000
raw: 0000000000000001 0000000000000006 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff0000e51bff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff0000e51bff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000e51c0000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff0000e51c0080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff0000e51c0100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================


---
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[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: f6e38ae624cf Linux 6.1.158
git tree: linux-6.1.y

console output: https://syzkaller.appspot.com/x/log.txt?x=16b798c2580000

kernel config: https://syzkaller.appspot.com/x/.config?x=68aa5a3af1cb953a
dashboard link: https://syzkaller.appspot.com/bug?extid=55a6d34a3a95c58633df
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1381f912580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11b9c512580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c1bd671a9def/disk-f6e38ae6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fa0af998ea40/vmlinux-f6e38ae6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/e5512d873524/Image-f6e38ae6.gz.xz

mounted in repro: https://storage.googleapis.com/syzbot-assets/ce514a60487a/mount_0.gz
fsck result: OK (log: https://syzkaller.appspot.com/x/fsck.log?x=1581f912580000)

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+55a6d3...@syzkaller.appspotmail.com

JBD2: Ignoring recovery information on journal
ocfs2: Mounting device (7,0) on (node local, slot 0) with ordered data mode.

==================================================================
BUG: KASAN: use-after-free in ocfs2_xattr_get_type fs/ocfs2/ocfs2_fs.h:1113 [inline]
BUG: KASAN: use-after-free in ocfs2_xattr_list_entries fs/ocfs2/xattr.c:938 [inline]
BUG: KASAN: use-after-free in ocfs2_xattr_ibody_list fs/ocfs2/xattr.c:986 [inline]
BUG: KASAN: use-after-free in ocfs2_listxattr+0x408/0xa74 fs/ocfs2/xattr.c:1048

Read of size 1 at addr ffff0000eb662007 by task syz.0.17/4536

CPU: 0 PID: 4536 Comm: syz.0.17 Not tainted syzkaller #0

page:0000000048198fa7 refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x12b662
flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000000000 fffffc0003ad8b08 fffffc0003ad96c8 0000000000000000
raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000

page dumped because: kasan: bad access detected

Memory state around the buggy address:

ffff0000eb661f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff0000eb661f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000eb662000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff0000eb662080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff0000eb662100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================


---
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