[syzbot] [ntfs3?] WARNING in ntfs_put_super

[syzbot] [ntfs3?] WARNING in ntfs_put_super

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    f7d2388eeec2 Add linux-next specific files for 20251028
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=12169f34580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ecdce5bceba74f
dashboard link: https://syzkaller.appspot.com/bug?extid=cc433e4cd6d54736bf80
compiler:       Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=13dedfe2580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15eaf614580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8aa0aaa475d1/disk-f7d2388e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/fc97cba5a8b0/vmlinux-f7d2388e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/30e4617d837c/bzImage-f7d2388e.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/4f46697dcc18/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cc433e4cd6d54736bf80@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: mm/slub.c:6752 at free_large_kmalloc+0x15c/0x1f0 mm/slub.c:6752, CPU#1: syz-executor/5941
Modules linked in:
CPU: 1 UID: 0 PID: 5941 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:free_large_kmalloc+0x15c/0x1f0 mm/slub.c:6752
Code: 44 89 f6 e8 16 d1 fc ff 65 48 8b 05 1e c3 57 10 48 3b 44 24 08 75 57 48 83 c4 10 5b 41 5c 41 5e 41 5f 5d e9 86 7b 3b 09 cc 90 <0f> 0b 90 65 48 8b 05 f9 c2 57 10 48 3b 44 24 08 75 32 48 89 df 48
RSP: 0018:ffffc900037ffc88 EFLAGS: 00010206
RAX: 00000000ff000000 RBX: ffffea0000389440 RCX: ffffea0000389448
RDX: 0000000000000000 RSI: ffffffff8e251920 RDI: ffffea0000389440
RBP: 1ffff1100f55d143 R08: ffffffff8f7d5a77 R09: 1ffffffff1efab4e
R10: dffffc0000000000 R11: fffffbfff1efab4f R12: 1ffff1100f55d136
R13: dffffc0000000000 R14: ffff88807aae89b0 R15: ffff8880793b0ec8
FS:  000055557fea9500(0000) GS:ffff888125feb000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055557fec45c8 CR3: 0000000029608000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 ntfs_put_super+0x15b/0x1b0 fs/ntfs3/super.c:708
 generic_shutdown_super+0x135/0x2c0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1722
 ntfs3_kill_sb+0x44/0x1b0 fs/ntfs3/super.c:1847
 deactivate_locked_super+0xbc/0x130 fs/super.c:473
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2e3c7902f7
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffcc218b908 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f2e3c811d7d RCX: 00007f2e3c7902f7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcc218b9c0
RBP: 00007ffcc218b9c0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcc218ca50
R13: 00007f2e3c811d7d R14: 0000000000019cb4 R15: 00007ffcc218ca90
 </TASK>


---
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[PATCH next] ntfs3: Remove redundant nls free

[Edward Adam Davis]

Using unload_nls() is sufficient for nls.

syzbot reported:
WARNING: mm/slub.c:6752 at free_large_kmalloc+0x15c/0x1f0 mm/slub.c:6752, CPU#1: syz-executor/5939
Call Trace:
 ntfs_put_super+0x15b/0x1b0 fs/ntfs3/super.c:708
 generic_shutdown_super+0x135/0x2c0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1722
 ntfs3_kill_sb+0x44/0x1b0 fs/ntfs3/super.c:1847

Reported-by: syzbot+cc433e4cd6d54736bf80@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=cc433e4cd6d54736bf80
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
 fs/ntfs3/super.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index aae1f32f4dab..02b03d810dcf 100644
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -705,7 +705,6 @@ static void ntfs_put_super(struct super_block *sb)
 
 	if (sbi->options) {
 		unload_nls(sbi->options->nls);
-		kfree(sbi->options->nls);
 		kfree(sbi->options);
 		sbi->options = NULL;
 	}
-- 
2.43.0

Re: [syzbot] [ntfs3?] WARNING in ntfs_put_super

[syzbot]

syzbot has bisected this issue to:

commit 02f312754c873efe076888a2fdca982e56617929
Author: YangWen <anmuxixixi@gmail.com>
Date:   Wed Sep 10 15:17:08 2025 +0000

    ntfs3: fix use-after-free of sbi->options in cmp_fnames

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=12ba4bcd980000
start commit:   f7d2388eeec2 Add linux-next specific files for 20251028
git tree:       linux-next
final oops:     https://syzkaller.appspot.com/x/report.txt?x=11ba4bcd980000
console output: https://syzkaller.appspot.com/x/log.txt?x=16ba4bcd980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=ecdce5bceba74f
dashboard link: https://syzkaller.appspot.com/bug?extid=cc433e4cd6d54736bf80
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16b73d42580000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1019dfe2580000

Reported-by: syzbot+cc433e4cd6d54736bf80@syzkaller.appspotmail.com
Fixes: 02f312754c87 ("ntfs3: fix use-after-free of sbi->options in cmp_fnames")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection