[PATCH v2 01/13] teach filename_lookup() to treat NULL filename as ""

[Al Viro <viro@zeniv.linux.org.uk>]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
 fs/namei.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/namei.c b/fs/namei.c
index 4a4a22a08ac2..aaf3cd6c802f 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -588,6 +588,7 @@ struct nameidata {
 		unsigned seq;
 	} *stack, internal[EMBEDDED_LEVELS];
 	struct filename	*name;
+	const char *pathname;
 	struct nameidata *saved;
 	unsigned	root_seq;
 	int		dfd;
@@ -606,6 +607,7 @@ static void __set_nameidata(struct nameidata *p, int dfd, struct filename *name)
 	p->depth = 0;
 	p->dfd = dfd;
 	p->name = name;
+	p->pathname = likely(name) ? name->name : "";
 	p->path.mnt = NULL;
 	p->path.dentry = NULL;
 	p->total_link_count = old ? old->total_link_count : 0;
@@ -2439,7 +2441,7 @@ static int link_path_walk(const char *name, struct nameidata *nd)
 static const char *path_init(struct nameidata *nd, unsigned flags)
 {
 	int error;
-	const char *s = nd->name->name;
+	const char *s = nd->pathname;
 
 	/* LOOKUP_CACHED requires RCU, ask caller to retry */
 	if ((flags & (LOOKUP_RCU | LOOKUP_CACHED)) == LOOKUP_CACHED)
-- 
2.39.5