selinux: fix dentry_open() error check

The return value of dentry_open() shoud be checked by IS_ERR().

Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 8ab5679a37a3..28ee187ed224 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -1754,7 +1754,8 @@ static inline void flush_unauthorized_files(struct files_struct * files)
                                                 get_file(devnull);
                                         } else {
                                                 devnull = dentry_open(dget(selinux_null), mntget(selinuxfs_mount), O_RDWR);
-                                                if (!devnull) {
+                                                if (IS_ERR(devnull)) {
+                                                        devnull = NULL;
                                                         put_unused_fd(fd);
                                                         fput(file);
                                                         continue;