[PATCH] eCryptfs: fix possible NULL ptr deref in ecryptfs_d_release()
ecryptfs_d_release() first dereferences a pointer (via
ecryptfs_dentry_to_lower()) and then afterwards checks to see if the
pointer it just dereferenced is NULL (via ecryptfs_dentry_to_private()).
This patch moves all of the work done on the dereferenced pointer inside a
block governed by the condition that the pointer is non-NULL.
Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/ecryptfs/dentry.c b/fs/ecryptfs/dentry.c
index 329efcd..cb20b96 100644
--- a/fs/ecryptfs/dentry.c
+++ b/fs/ecryptfs/dentry.c
@@ -78,18 +78,13 @@
*/
static void ecryptfs_d_release(struct dentry *dentry)
{
- struct dentry *lower_dentry;
-
- lower_dentry = ecryptfs_dentry_to_lower(dentry);
- if (ecryptfs_dentry_to_private(dentry))
+ if (ecryptfs_dentry_to_private(dentry)) {
+ if (ecryptfs_dentry_to_lower(dentry)) {
+ mntput(ecryptfs_dentry_to_lower_mnt(dentry));
+ dput(ecryptfs_dentry_to_lower(dentry));
+ }
kmem_cache_free(ecryptfs_dentry_info_cache,
ecryptfs_dentry_to_private(dentry));
- if (lower_dentry) {
- struct vfsmount *lower_mnt =
- ecryptfs_dentry_to_lower_mnt(dentry);
-
- mntput(lower_mnt);
- dput(lower_dentry);
}
return;
}