TOMOYO: Fix memory leak upon file open.

In tomoyo_check_open_permission() since 2.6.36, TOMOYO was by error
recalculating already calculated pathname when checking allow_rewrite
permission. As a result, memory will leak whenever a file is opened for writing
without O_APPEND flag. Also, performance will degrade because TOMOYO is
calculating pathname regardless of profile configuration.
This patch fixes the leak and performance degrade.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 1 insertions, 4 deletions

diff --git a/security/tomoyo/file.c b/security/tomoyo/file.c
index 9d32f182301e..cb09f1fce910 100644
--- a/security/tomoyo/file.c
+++ b/security/tomoyo/file.c
@@ -927,7 +927,7 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
                                  struct path *path, const int flag)
 {
         const u8 acc_mode = ACC_MODE(flag);
-        int error = -ENOMEM;
+        int error = 0;
         struct tomoyo_path_info buf;
         struct tomoyo_request_info r;
         int idx;
@@ -938,9 +938,6 @@ int tomoyo_check_open_permission(struct tomoyo_domain_info *domain,
         buf.name = NULL;
         r.mode = TOMOYO_CONFIG_DISABLED;
         idx = tomoyo_read_lock();
-        if (!tomoyo_get_realpath(&buf, path))
-                goto out;
-        error = 0;
         /*
          * If the filename is specified by "deny_rewrite" keyword,
          * we need to check "allow_rewrite" permission when the filename is not