author: Tejun Heo <tj@kernel.org> 2016-01-15 12:30:14 -0500
committer: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 2016-02-07 20:21:35 -0800
commit: e56ed358afd81554e668aaa974d3f9ed201fa10d
parent: 388f7b1d6e8ca06762e2454d28d6c3c55ad0fe95
Commit Summary:
Diffstat:
1 file changed, 11 insertions, 5 deletions
diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c
index 996b7742c90b..118d033bcbbc 100644
--- a/fs/kernfs/dir.c
+++ b/fs/kernfs/dir.c
@@ -691,15 +691,22 @@ static struct kernfs_node *kernfs_walk_ns(struct kernfs_node *parent,
const unsigned char *path,
const void *ns)
{
- static char path_buf[PATH_MAX]; /* protected by kernfs_mutex */
- size_t len = strlcpy(path_buf, path, PATH_MAX);
- char *p = path_buf;
- char *name;
+ size_t len;
+ char *p, *name;
lockdep_assert_held(&kernfs_mutex);
- if (len >= PATH_MAX)
+ /* grab kernfs_rename_lock to piggy back on kernfs_pr_cont_buf */
+ spin_lock_irq(&kernfs_rename_lock);
+
+ len = strlcpy(kernfs_pr_cont_buf, path, sizeof(kernfs_pr_cont_buf));
+
+ if (len >= sizeof(kernfs_pr_cont_buf)) {
+ spin_unlock_irq(&kernfs_rename_lock);
return NULL;
+ }
+
+ p = kernfs_pr_cont_buf;
while ((name = strsep(&p, "/")) && parent) {
if (*name == '\0')
@@ -707,6 +714,8 @@ static struct kernfs_node *kernfs_walk_ns(struct kernfs_node *parent,
parent = kernfs_find_ns(parent, name, ns);
}
+ spin_unlock_irq(&kernfs_rename_lock);
+
return parent;
}