[syzbot] [ntfs3?] KASAN: slab-out-of-bounds Read in ntfs_listxattr (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aafe7ad77b91 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=15412f76e80000
kernel config: https://syzkaller.appspot.com/x/.config?x=23ce86eb3d78ef4d
dashboard link: https://syzkaller.appspot.com/bug?extid=65e940cfb8f99a97aca7
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=10627f76e80000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1400171ae80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/23845238c49b/disk-aafe7ad7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1144b0f74104/vmlinux-aafe7ad7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6db20df213a2/Image-aafe7ad7.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/4f0ec668b8cf/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+65e940...@syzkaller.appspotmail.com

ntfs3: loop0: Different NTFS sector size (4096) and media sector size (512).
ntfs3: loop0: Failed to initialize $Extend/$Reparse.
ntfs3: loop0: Mark volume as dirty due to NTFS errors
==================================================================
BUG: KASAN: slab-out-of-bounds in ntfs_list_ea fs/ntfs3/xattr.c:232 [inline]
BUG: KASAN: slab-out-of-bounds in ntfs_listxattr+0x354/0x50c fs/ntfs3/xattr.c:733
Read of size 48 at addr ffff0000d0125c30 by task syz-executor346/6095

CPU: 1 PID: 6095 Comm: syz-executor346 Not tainted 6.7.0-rc6-syzkaller-gaafe7ad77b91 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Call trace:
dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:291
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:298
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0x174/0x514 mm/kasan/report.c:475
kasan_report+0xd8/0x138 mm/kasan/report.c:588
kasan_check_range+0x254/0x294 mm/kasan/generic.c:187
__asan_memcpy+0x3c/0x84 mm/kasan/shadow.c:105
ntfs_list_ea fs/ntfs3/xattr.c:232 [inline]
ntfs_listxattr+0x354/0x50c fs/ntfs3/xattr.c:733
vfs_listxattr fs/xattr.c:494 [inline]
listxattr+0x108/0x368 fs/xattr.c:841
path_listxattr fs/xattr.c:865 [inline]
__do_sys_llistxattr fs/xattr.c:883 [inline]
__se_sys_llistxattr fs/xattr.c:880 [inline]
__arm64_sys_llistxattr+0x13c/0x21c fs/xattr.c:880
__invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595

Allocated by task 6095:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4c/0x7c mm/kasan/common.c:52
kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:511
____kasan_kmalloc mm/kasan/common.c:374 [inline]
__kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:383
kasan_kmalloc include/linux/kasan.h:198 [inline]
__do_kmalloc_node mm/slab_common.c:1007 [inline]
__kmalloc+0xcc/0x1b8 mm/slab_common.c:1020
kmalloc include/linux/slab.h:604 [inline]
ntfs_read_ea+0x3c0/0x808 fs/ntfs3/xattr.c:118
ntfs_list_ea fs/ntfs3/xattr.c:204 [inline]
ntfs_listxattr+0x14c/0x50c fs/ntfs3/xattr.c:733
vfs_listxattr fs/xattr.c:494 [inline]
listxattr+0x108/0x368 fs/xattr.c:841
path_listxattr fs/xattr.c:865 [inline]
__do_sys_llistxattr fs/xattr.c:883 [inline]
__se_sys_llistxattr fs/xattr.c:880 [inline]
__arm64_sys_llistxattr+0x13c/0x21c fs/xattr.c:880
__invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595

The buggy address belongs to the object at ffff0000d0125c00
which belongs to the cache kmalloc-64 of size 64
The buggy address is located 48 bytes inside of
allocated 60-byte region [ffff0000d0125c00, ffff0000d0125c3c)

The buggy address belongs to the physical page:
page:000000003d4f3554 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x110125
ksm flags: 0x5ffc00000000800(slab|node=0|zone=2|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 05ffc00000000800 ffff0000c0001640 fffffc0003376b40 dead000000000003
raw: 0000000000000000 0000000080200020 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff0000d0125b00: 00 00 00 00 00 00 02 fc fc fc fc fc fc fc fc fc
ffff0000d0125b80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
>ffff0000d0125c00: 00 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc
^
ffff0000d0125c80: 00 00 00 00 00 00 04 fc fc fc fc fc fc fc fc fc
ffff0000d0125d00: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
==================================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[Edward Adam Davis]

please test slab-out-of-bounds Read in ntfs_listxattr

#syz test git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git aafe7ad77b91

diff --git a/fs/ntfs3/xattr.c b/fs/ntfs3/xattr.c
index 4274b6f31cfa..3b97508a7bf2 100644
--- a/fs/ntfs3/xattr.c
+++ b/fs/ntfs3/xattr.c
@@ -219,6 +219,9 @@ static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
if (!ea->name_len)
break;

+ if (ea->name_len > ea_size)
+ break;
+
if (buffer) {
/* Check if we can use field ea->name */
if (off + ea_size > size)

[syzbot]

Hello,

syzbot has tested the proposed patch and the reproducer did not trigger any issue:

Reported-and-tested-by: syzbot+65e940...@syzkaller.appspotmail.com

Tested on:

commit: aafe7ad7 Merge branch 'for-next/core' into for-kernelci
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git
console output: https://syzkaller.appspot.com/x/log.txt?x=12128e7ee80000

kernel config: https://syzkaller.appspot.com/x/.config?x=23ce86eb3d78ef4d
dashboard link: https://syzkaller.appspot.com/bug?extid=65e940cfb8f99a97aca7
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

patch: https://syzkaller.appspot.com/x/patch.diff?x=14b48c9ae80000

Note: testing is done by a robot and is best-effort only.

[Edward Adam Davis]

The length of name cannot exceed the space occupied by ea.

Reported-and-tested-by: syzbot+65e940...@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <ead...@qq.com>
---
fs/ntfs3/xattr.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/fs/ntfs3/xattr.c b/fs/ntfs3/xattr.c
index 4274b6f31cfa..3b97508a7bf2 100644
--- a/fs/ntfs3/xattr.c
+++ b/fs/ntfs3/xattr.c
@@ -219,6 +219,9 @@ static ssize_t ntfs_list_ea(struct ntfs_inode *ni, char *buffer,
if (!ea->name_len)
break;

+ if (ea->name_len > ea_size)
+ break;
+
if (buffer) {
/* Check if we can use field ea->name */
if (off + ea_size > size)

--
2.43.0