Re: [syzbot] Private message regarding: [syzbot] [ntfs3?] WARNING in ni_rename

[syzbot <syzbot+b0373017f711c06ada64@syzkaller.appspotmail.com>]

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***

Subject: Private message regarding: [syzbot] [ntfs3?] WARNING in ni_rename
Author: kapoorarnav43@gmail.com

#syz test: 
git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
From 00325fe8a9658ef0d9e0082dd98c09adc01875fa Mon Sep 17 00:00:00 2001
From: Arnav Kapoor <kapoor...@gmail.com>
Date: Sun, 29 Jun 2025 15:29:27 +0530
Subject: [PATCH] ntfs3: log error when cleanup in ni_rename fails

If ni_remove_name fails and undoing ni_add_name also fails,
add an error log so the failure is visible.

Reported-by: syzbot+b0373017f711c06ada64@syzkaller.appspotmail.com
Signed-off-by: Arnav Kapoor <kapoor...@gmail.com>
---
 fs/ntfs3/frecord.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/fs/ntfs3/frecord.c b/fs/ntfs3/frecord.c
index b7a83200f2cc..8e9d2ea4e37e 100644
--- a/fs/ntfs3/frecord.c
+++ b/fs/ntfs3/frecord.c
@@ int ni_rename(struct ntfs_inode *dir_ni, struct ntfs_inode *new_dir_ni,
                struct ntfs_inode *ni, struct dentry *de, struct dentry 
*new_de,
                bool *is_bad)
 {
+       struct super_block *sb = ni->mi.sbi->sb;
        int err;
        struct ntfs_dir_entry *de2;
        bool undo;
 
        err = ni_add_name(new_dir_ni, ni, new_de);
        if (!err) {
                err = ni_remove_name(dir_ni, ni, de, &de2, &undo);
-               if (err && ni_remove_name(new_dir_ni, ni, new_de, &de2, 
&undo))
+               if (err && ni_remove_name(new_dir_ni, ni, new_de, &de2, 
&undo)) {
+                       ntfs_err(sb, "ni_rename: failed to clean up after 
add_name failure");
                        *is_bad = true;
+               }
        }
 
        /*
-- 
2.43.0


On Monday, 30 June 2025 at 16:51:05 UTC+5:30 syzbot wrote:

Hello, 

syzbot tried to test the proposed patch but the build/boot failed: 

failed to apply patch: 
checking file fs/ntfs3/frecord.c 
Hunk #1 FAILED at 3027. 
1 out of 1 hunk FAILED 



Tested on: 

commit: 1343433e Add linux-next specific files for 20250630 
git tree: linux-next 
kernel config: https://syzkaller.appspot.com/x/.config?x=a3d8d413c6928dae 
dashboard link: https://syzkaller.appspot.com/bug?extid=b0373017f711c06ada64 
compiler: 
patch: https://syzkaller.appspot.com/x/patch.diff?x=115cb88c580000