stack: Reduce stack usage for local variables to store tmpfile names

This patch moves stack based PATH_MAX allocations for tmpfile
names, to heap allocated names instead. Reducing the impact on
stack space used and accruing benefits thereof.

Change-Id: I646d9cb091018de6768b3523902788fa2ba14d96
Updates: bz#1193929
Signed-off-by: ShyamsundarR <srangana@redhat.com>

4 files changed, 62 insertions, 22 deletions

diff --git a/libglusterfs/src/graph.y b/libglusterfs/src/graph.y
index bf7886b5a8e..3c3f7b5bb82 100644
--- a/libglusterfs/src/graph.y
+++ b/libglusterfs/src/graph.y
@@ -555,14 +555,13 @@ glusterfs_graph_construct (FILE *fp)
         int                tmp_fd = -1;
         glusterfs_graph_t *graph = NULL;
         FILE              *tmp_file = NULL;
-        char               template[PATH_MAX] = {0};
+        char               template[] = "/tmp/tmp.XXXXXX";
 	static pthread_mutex_t graph_mutex = PTHREAD_MUTEX_INITIALIZER;
 
         graph = glusterfs_graph_new ();
         if (!graph)
                 goto err;
 
-        strcpy (template, "/tmp/tmp.XXXXXX");
         /* coverity[secure_temp] mkstemp uses 0600 as the mode and is safe */
         tmp_fd = mkstemp (template);
         if (-1 == tmp_fd)
diff --git a/xlators/mgmt/glusterd/src/glusterd-gfproxyd-svc-helper.c b/xlators/mgmt/glusterd/src/glusterd-gfproxyd-svc-helper.c
index 781cdbf6818..72baa3424e9 100644
--- a/xlators/mgmt/glusterd/src/glusterd-gfproxyd-svc-helper.c
+++ b/xlators/mgmt/glusterd/src/glusterd-gfproxyd-svc-helper.c
@@ -90,7 +90,7 @@ glusterd_is_gfproxyd_enabled (glusterd_volinfo_t *volinfo)
 
 static int
 glusterd_svc_get_gfproxyd_volfile (glusterd_volinfo_t *volinfo, char *svc_name,
-                                   char *orgvol, char *tmpvol, int path_len)
+                                   char *orgvol, char **tmpvol, int path_len)
 {
         int             tmp_fd                  = -1;
         int             ret                     = -1;
@@ -99,23 +99,31 @@ glusterd_svc_get_gfproxyd_volfile (glusterd_volinfo_t *volinfo, char *svc_name,
         glusterd_svc_build_gfproxyd_volfile_path (volinfo, orgvol,
                                                   path_len);
 
-        snprintf (tmpvol, path_len, "/tmp/g%s-XXXXXX", svc_name);
+        ret = gf_asprintf(tmpvol, "/tmp/g%s-XXXXXX", svc_name);
+        if (ret < 0) {
+                goto out;
+        }
 
         /* coverity[secure_temp] mkstemp uses 0600 as the mode and is safe */
-        tmp_fd = mkstemp (tmpvol);
+        tmp_fd = mkstemp (*tmpvol);
         if (tmp_fd < 0) {
                 gf_msg ("glusterd", GF_LOG_WARNING, errno,
                         GD_MSG_FILE_OP_FAILED, "Unable to create temp file"
-                        " %s:(%s)", tmpvol, strerror (errno));
+                        " %s:(%s)", *tmpvol, strerror (errno));
+                ret = -1;
                 goto out;
         }
 
         need_unlink = 1;
-        ret = glusterd_build_gfproxyd_volfile (volinfo, tmpvol);
-
+        ret = glusterd_build_gfproxyd_volfile (volinfo, *tmpvol);
 out:
         if (need_unlink && ret < 0)
-                sys_unlink (tmpvol);
+                sys_unlink (*tmpvol);
+
+        if ((ret < 0) && (*tmpvol != NULL)) {
+                GF_FREE(*tmpvol);
+                *tmpvol = NULL;
+        }
 
         if (tmp_fd >= 0)
                 sys_close (tmp_fd);
@@ -129,14 +137,14 @@ glusterd_svc_check_gfproxyd_volfile_identical (char *svc_name,
                                                gf_boolean_t *identical)
 {
         char            orgvol[PATH_MAX]        = {0,};
-        char            tmpvol[PATH_MAX]        = {0,};
+        char           *tmpvol                  = NULL;
         int             ret                     = -1;
         int             need_unlink             = 0;
 
         GF_VALIDATE_OR_GOTO ("glusterd", identical, out);
 
         ret = glusterd_svc_get_gfproxyd_volfile (volinfo, svc_name, orgvol,
-                                                 tmpvol, PATH_MAX);
+                                                 &tmpvol, PATH_MAX);
         if (ret)
                 goto out;
 
@@ -150,6 +158,9 @@ out:
         if (need_unlink)
                 sys_unlink (tmpvol);
 
+        if (tmpvol != NULL)
+                GF_FREE (tmpvol);
+
         return ret;
 }
 
@@ -159,14 +170,14 @@ glusterd_svc_check_gfproxyd_topology_identical (char *svc_name,
                                                 gf_boolean_t *identical)
 {
         char            orgvol[PATH_MAX]        = {0,};
-        char            tmpvol[PATH_MAX]        = {0,};
+        char           *tmpvol                  = NULL;
         int             ret                     = -1;
         int             tmpclean                = 0;
 
         GF_VALIDATE_OR_GOTO ("glusterd", identical, out);
 
         ret = glusterd_svc_get_gfproxyd_volfile (volinfo, svc_name, orgvol,
-                                                 tmpvol, PATH_MAX);
+                                                 &tmpvol, PATH_MAX);
         if (ret)
                 goto out;
 
@@ -178,6 +189,10 @@ glusterd_svc_check_gfproxyd_topology_identical (char *svc_name,
 out:
         if (tmpclean)
                 sys_unlink (tmpvol);
+
+        if (tmpvol != NULL)
+                GF_FREE (tmpvol);
+
         return ret;
 }
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-svc-helper.c b/xlators/mgmt/glusterd/src/glusterd-svc-helper.c
index abf979eada5..40726dbfb3e 100644
--- a/xlators/mgmt/glusterd/src/glusterd-svc-helper.c
+++ b/xlators/mgmt/glusterd/src/glusterd-svc-helper.c
@@ -162,7 +162,7 @@ glusterd_svc_check_volfile_identical (char *svc_name,
                                       gf_boolean_t *identical)
 {
         char            orgvol[PATH_MAX]        = {0,};
-        char            tmpvol[PATH_MAX]        = {0,};
+        char            *tmpvol                 = NULL;
         glusterd_conf_t *conf                   = NULL;
         xlator_t        *this                   = NULL;
         int             ret                     = -1;
@@ -178,7 +178,10 @@ glusterd_svc_check_volfile_identical (char *svc_name,
         glusterd_svc_build_volfile_path (svc_name, conf->workdir,
                                          orgvol, sizeof (orgvol));
 
-        snprintf (tmpvol, sizeof (tmpvol), "/tmp/g%s-XXXXXX", svc_name);
+        ret = gf_asprintf(&tmpvol, "/tmp/g%s-XXXXXX", svc_name);
+        if (ret < 0) {
+                goto out;
+        }
 
         /* coverity[secure_temp] mkstemp uses 0600 as the mode and is safe */
         tmp_fd = mkstemp (tmpvol);
@@ -186,6 +189,7 @@ glusterd_svc_check_volfile_identical (char *svc_name,
                 gf_msg (this->name, GF_LOG_WARNING, errno,
                         GD_MSG_FILE_OP_FAILED, "Unable to create temp file"
                         " %s:(%s)", tmpvol, strerror (errno));
+                ret = -1;
                 goto out;
         }
 
@@ -196,11 +200,13 @@ glusterd_svc_check_volfile_identical (char *svc_name,
                 goto out;
 
         ret = glusterd_check_files_identical (orgvol, tmpvol, identical);
-
 out:
         if (need_unlink)
                 sys_unlink (tmpvol);
 
+        if (tmpvol != NULL)
+                GF_FREE(tmpvol);
+
         if (tmp_fd >= 0)
                 sys_close (tmp_fd);
 
@@ -213,7 +219,7 @@ glusterd_svc_check_topology_identical (char *svc_name,
                                        gf_boolean_t *identical)
 {
         char            orgvol[PATH_MAX]        = {0,};
-        char            tmpvol[PATH_MAX]        = {0,};
+        char            *tmpvol                 = NULL;
         glusterd_conf_t *conf                   = NULL;
         xlator_t        *this                   = THIS;
         int             ret                     = -1;
@@ -231,13 +237,18 @@ glusterd_svc_check_topology_identical (char *svc_name,
                                          orgvol, sizeof (orgvol));
 
         /* Create the temporary volfile */
-        snprintf (tmpvol, sizeof (tmpvol), "/tmp/g%s-XXXXXX", svc_name);
+        ret = gf_asprintf(&tmpvol, "/tmp/g%s-XXXXXX", svc_name);
+        if (ret < 0) {
+                goto out;
+        }
+
         /* coverity[secure_temp] mkstemp uses 0600 as the mode and is safe */
         tmpfd = mkstemp (tmpvol);
         if (tmpfd < 0) {
                 gf_msg (this->name, GF_LOG_WARNING, errno,
                         GD_MSG_FILE_OP_FAILED, "Unable to create temp file"
                         " %s:(%s)", tmpvol, strerror (errno));
+                ret = -1;
                 goto out;
         }
 
@@ -256,5 +267,7 @@ out:
                 sys_close (tmpfd);
         if (tmpclean)
                 sys_unlink (tmpvol);
+        if (tmpvol != NULL)
+                GF_FREE(tmpvol);
         return ret;
 }
diff --git a/xlators/mgmt/glusterd/src/glusterd-tierd-svc-helper.c b/xlators/mgmt/glusterd/src/glusterd-tierd-svc-helper.c
index 8b54ac10594..b8e373e7e83 100644
--- a/xlators/mgmt/glusterd/src/glusterd-tierd-svc-helper.c
+++ b/xlators/mgmt/glusterd/src/glusterd-tierd-svc-helper.c
@@ -89,7 +89,7 @@ glusterd_svc_check_tier_volfile_identical (char *svc_name,
                                            gf_boolean_t *identical)
 {
         char            orgvol[PATH_MAX]        = {0,};
-        char            tmpvol[PATH_MAX]        = {0,};
+        char            *tmpvol                 = NULL;
         xlator_t        *this                   = NULL;
         int             ret                     = -1;
         int             need_unlink             = 0;
@@ -103,7 +103,10 @@ glusterd_svc_check_tier_volfile_identical (char *svc_name,
         glusterd_svc_build_tierd_volfile_path (volinfo, orgvol,
                         sizeof (orgvol));
 
-        snprintf (tmpvol, sizeof (tmpvol), "/tmp/g%s-XXXXXX", svc_name);
+        ret = gf_asprintf(&tmpvol, "/tmp/g%s-XXXXXX", svc_name);
+        if (ret < 0) {
+                goto out;
+        }
 
         /* coverity[secure_temp] mkstemp uses 0600 as the mode and is safe */
         tmp_fd = mkstemp (tmpvol);
@@ -111,6 +114,7 @@ glusterd_svc_check_tier_volfile_identical (char *svc_name,
                 gf_msg (this->name, GF_LOG_WARNING, errno,
                         GD_MSG_FILE_OP_FAILED, "Unable to create temp file"
                         " %s:(%s)", tmpvol, strerror (errno));
+                ret = -1;
                 goto out;
         }
 
@@ -128,6 +132,9 @@ out:
         if (need_unlink)
                 sys_unlink (tmpvol);
 
+        if (tmpvol != NULL)
+                GF_FREE(tmpvol);
+
         if (tmp_fd >= 0)
                 sys_close (tmp_fd);
 
@@ -140,7 +147,7 @@ glusterd_svc_check_tier_topology_identical (char *svc_name,
                                        gf_boolean_t *identical)
 {
         char            orgvol[PATH_MAX]        = {0,};
-        char            tmpvol[PATH_MAX]        = {0,};
+        char            *tmpvol                 = NULL;
         glusterd_conf_t *conf                   = NULL;
         xlator_t        *this                   = THIS;
         int             ret                     = -1;
@@ -157,7 +164,10 @@ glusterd_svc_check_tier_topology_identical (char *svc_name,
         glusterd_svc_build_tierd_volfile_path (volinfo, orgvol,
                         sizeof (orgvol));
 
-        snprintf (tmpvol, sizeof (tmpvol), "/tmp/g%s-XXXXXX", svc_name);
+        ret = gf_asprintf(&tmpvol, "/tmp/g%s-XXXXXX", svc_name);
+        if (ret < 0) {
+                goto out;
+        }
 
         /* coverity[secure_temp] mkstemp uses 0600 as the mode and is safe */
         tmpfd = mkstemp (tmpvol);
@@ -165,6 +175,7 @@ glusterd_svc_check_tier_topology_identical (char *svc_name,
                 gf_msg (this->name, GF_LOG_WARNING, errno,
                         GD_MSG_FILE_OP_FAILED, "Unable to create temp file"
                         " %s:(%s)", tmpvol, strerror (errno));
+                ret = -1;
                 goto out;
         }
 
@@ -181,5 +192,7 @@ out:
                 sys_close (tmpfd);
         if (tmpclean)
                 sys_unlink (tmpvol);
+        if (tmpvol != NULL)
+                GF_FREE(tmpvol);
         return ret;
 }