[PATCH 4.2.y-ckt 103/305] Don't reset ->total_link_count on nested calls of vfs_path_lookup()

From: Kamal Mostafa
Date: Fri Jan 15 2016 - 20:07:07 EST


4.2.8-ckt2 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

commit 2788cc47f4593cca2c3c73c7bb82cd32b88c8ef7 upstream.

we already zero it on outermost set_nameidata(), so initialization in
path_init() is pointless and wrong. The same DoS exists on pre-4.2
kernels, but there a slightly different fix will be needed.

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
fs/namei.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/fs/namei.c b/fs/namei.c
index 36df481..f39a798 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -1999,7 +1999,6 @@ static const char *path_init(struct nameidata *nd, unsigned flags)
nd->last_type = LAST_ROOT; /* if there are only slashes... */
nd->flags = flags | LOOKUP_JUMPED | LOOKUP_PARENT;
nd->depth = 0;
- nd->total_link_count = 0;
if (flags & LOOKUP_ROOT) {
struct dentry *root = nd->root.dentry;
struct inode *inode = root->d_inode;
--
1.9.1