[syzbot] KASAN: use-after-free Read in ntfs_test_inode

From: syzbot
Date: Mon May 17 2021 - 06:56:34 EST


Hello,

syzbot found the following issue on:

HEAD commit: 9cdbf646 Merge tag 'io_uring-5.12-2021-04-16' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11684629d00000
kernel config: https://syzkaller.appspot.com/x/.config?x=330c6a2c09278509
dashboard link: https://syzkaller.appspot.com/bug?extid=2751da923b5eb8307b0b
compiler: Debian clang version 11.0.1-2

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

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+2751da923b5eb8307b0b@xxxxxxxxxxxxxxxxxxxxxxxxx

ntfs: volume version 3.1.
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline]
BUG: KASAN: use-after-free in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
BUG: KASAN: use-after-free in NInoAttr fs/ntfs/inode.h:200 [inline]
BUG: KASAN: use-after-free in ntfs_test_inode+0x7b/0x2d0 fs/ntfs/inode.c:55
Read of size 8 at addr ffff8880974790f0 by task syz-executor.3/12887

CPU: 1 PID: 12887 Comm: syz-executor.3 Not tainted 5.12.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack+0x176/0x24e lib/dump_stack.c:120
print_address_description+0x5f/0x3a0 mm/kasan/report.c:232
__kasan_report mm/kasan/report.c:399 [inline]
kasan_report+0x15c/0x200 mm/kasan/report.c:416
check_region_inline mm/kasan/generic.c:135 [inline]
kasan_check_range+0x2b5/0x2f0 mm/kasan/generic.c:186
instrument_atomic_read include/linux/instrumented.h:71 [inline]
test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline]
NInoAttr fs/ntfs/inode.h:200 [inline]
ntfs_test_inode+0x7b/0x2d0 fs/ntfs/inode.c:55
find_inode+0x10c/0x3e0 fs/inode.c:825
ilookup5_nowait fs/inode.c:1335 [inline]
ilookup5+0x9d/0x1f0 fs/inode.c:1364
iget5_locked+0x30/0x3d0 fs/inode.c:1145
ntfs_iget+0x73/0x130 fs/ntfs/inode.c:168
load_and_check_logfile fs/ntfs/super.c:1208 [inline]
load_system_files fs/ntfs/super.c:1941 [inline]
ntfs_fill_super+0x58f2/0x88e0 fs/ntfs/super.c:2893
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2903 [inline]
path_mount+0x188a/0x29a0 fs/namespace.c:3233
do_mount fs/namespace.c:3246 [inline]
__do_sys_mount fs/namespace.c:3454 [inline]
__se_sys_mount+0x28c/0x320 fs/namespace.c:3431
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x46797a
Code: 48 c7 c2 bc ff ff ff f7 d8 64 89 02 b8 ff ff ff ff eb d2 e8 b8 04 00 00 0f 1f 84 00 00 00 00 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f50a372bfa8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 0000000020000200 RCX: 000000000046797a
RDX: 0000000020000000 RSI: 0000000020000100 RDI: 00007f50a372c000
RBP: 00007f50a372c040 R08: 00007f50a372c040 R09: 0000000020000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000020000000
R13: 0000000020000100 R14: 00007f50a372c000 R15: 000000002007dc00

Allocated by task 11540:
kasan_save_stack mm/kasan/common.c:38 [inline]
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:427 [inline]
__kasan_slab_alloc+0x8f/0xc0 mm/kasan/common.c:460
kasan_slab_alloc include/linux/kasan.h:223 [inline]
slab_post_alloc_hook mm/slab.h:516 [inline]
slab_alloc_node mm/slub.c:2907 [inline]
slab_alloc mm/slub.c:2915 [inline]
kmem_cache_alloc+0x1c3/0x350 mm/slub.c:2920
reiserfs_alloc_inode+0x19/0xb0 fs/reiserfs/super.c:642
alloc_inode fs/inode.c:234 [inline]
new_inode_pseudo+0x61/0x220 fs/inode.c:928
new_inode+0x25/0x1d0 fs/inode.c:957
reiserfs_mkdir+0x129/0x800 fs/reiserfs/namei.c:812
xattr_mkdir fs/reiserfs/xattr.c:76 [inline]
create_privroot fs/reiserfs/xattr.c:889 [inline]
reiserfs_xattr_init+0x34b/0x730 fs/reiserfs/xattr.c:1012
reiserfs_fill_super+0x2aac/0x3160 fs/reiserfs/super.c:2177
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2903 [inline]
path_mount+0x188a/0x29a0 fs/namespace.c:3233
do_mount fs/namespace.c:3246 [inline]
__do_sys_mount fs/namespace.c:3454 [inline]
__se_sys_mount+0x28c/0x320 fs/namespace.c:3431
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

Last potentially related work creation:
kasan_save_stack+0x27/0x50 mm/kasan/common.c:38
kasan_record_aux_stack+0xee/0x120 mm/kasan/generic.c:345
__call_rcu kernel/rcu/tree.c:3039 [inline]
call_rcu+0x130/0x8e0 kernel/rcu/tree.c:3114
reiserfs_new_inode+0x690/0x2660 fs/reiserfs/inode.c:2164
reiserfs_mkdir+0x4a0/0x800 fs/reiserfs/namei.c:842
xattr_mkdir fs/reiserfs/xattr.c:76 [inline]
create_privroot fs/reiserfs/xattr.c:889 [inline]
reiserfs_xattr_init+0x34b/0x730 fs/reiserfs/xattr.c:1012
reiserfs_fill_super+0x2aac/0x3160 fs/reiserfs/super.c:2177
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2903 [inline]
path_mount+0x188a/0x29a0 fs/namespace.c:3233
do_mount fs/namespace.c:3246 [inline]
__do_sys_mount fs/namespace.c:3454 [inline]
__se_sys_mount+0x28c/0x320 fs/namespace.c:3431
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888097478c20
which belongs to the cache reiser_inode_cache of size 1424
The buggy address is located 1232 bytes inside of
1424-byte region [ffff888097478c20, ffff8880974791b0)
The buggy address belongs to the page:
page:ffffea00025d1e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888097479840 pfn:0x97478
head:ffffea00025d1e00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888018116500
raw: ffff888097479840 0000000080150014 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff888097478f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888097479000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888097479080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888097479100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888097479180: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
==================================================================


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