Re: [syzbot] possible fix (linux-ntfs3)

[syzbot <syzbot+4d2aaeff9eb5a2cfec70@syzkaller.appspotmail.com>]

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***

Subject: possible fix (linux-ntfs3)
Author: almaz.alexandrovich@paragon-software.com

#syz test: https://github.com/Paragon-Software-Group/linux-ntfs3.git master

diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c
index 128d49512f5d..c08bbacc0030 100644
--- a/fs/ntfs3/super.c
+++ b/fs/ntfs3/super.c
@@ -125,8 +125,9 @@ void ntfs_inode_printk(struct inode *inode, const 
char *fmt, ...)

          if (de) {
              spin_lock(&de->d_lock);
-            snprintf(name, sizeof(s_name_buf), " \"%s\"",
-                 de->d_name.name);
+            if (snprintf(name, sizeof(s_name_buf), " \"%s\"",
+                     de->d_name.name) >= sizeof(s_name_buf))
+                name[sizeof(s_name_buf) - 1] = 0;
              spin_unlock(&de->d_lock);
          } else {
              name[0] = 0;