From: Duane Griffin <duaneg@dghda.com>
Date: Fri, 19 Dec 2008 20:47:11 +0000 (+0000)
Subject: vfs: introduce helper function to safely NUL-terminate symlinks
X-Git-Tag: v2.6.29-rc1~549^2~27
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=035146851cfa2fe24c1d9dc7637bb009ad06b2f7;p=linux-2.6-omap-h63xx.git

vfs: introduce helper function to safely NUL-terminate symlinks

A number of filesystems were potentially triggering kernel bugs due to
corrupted symlink names on disk. This function helps safely terminate
the names.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/include/linux/namei.h b/include/linux/namei.h
index 99eb80306dc..fc2e0357987 100644
--- a/include/linux/namei.h
+++ b/include/linux/namei.h
@@ -94,4 +94,9 @@ static inline char *nd_get_link(struct nameidata *nd)
 	return nd->saved_names[nd->depth];
 }
 
+static inline void nd_terminate_link(void *name, size_t len, size_t maxlen)
+{
+	((char *) name)[min(len, maxlen)] = '\0';
+}
+
 #endif /* _LINUX_NAMEI_H */