core: coverity issues fixed

this is not a complete set of issues getting fixed. Will
address other issues in another patch.

Change-Id: Ib01c7b11b205078cc4d0b3f11610751e32d14b69
Signed-off-by: Amar Tumballi <amarts@redhat.com>
BUG: 789278
Reviewed-on: http://review.gluster.com/3145
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

22 files changed, 121 insertions, 67 deletions

diff --git a/xlators/cluster/dht/src/dht-layout.c b/xlators/cluster/dht/src/dht-layout.c
index d1f8c9fbb0d..3c583c7bde8 100644
--- a/xlators/cluster/dht/src/dht-layout.c
+++ b/xlators/cluster/dht/src/dht-layout.c
@@ -280,6 +280,9 @@ dht_disk_layout_extract (xlator_t *this, dht_layout_t *layout,
 
         if (disk_layout_p)
                 *disk_layout_p = disk_layout;
+        else
+                GF_FREE (disk_layout);
+
         ret = 0;
 
 out:
diff --git a/xlators/cluster/dht/src/dht-selfheal.c b/xlators/cluster/dht/src/dht-selfheal.c
index 420af4b7f93..9c8aeac2586 100644
--- a/xlators/cluster/dht/src/dht-selfheal.c
+++ b/xlators/cluster/dht/src/dht-selfheal.c
@@ -706,6 +706,9 @@ done:
                 local->layout = new_layout;
         }
 
+        if (fix_array)
+                GF_FREE (fix_array);
+
         return new_layout;
 }
 
diff --git a/xlators/cluster/stripe/src/stripe-helpers.c b/xlators/cluster/stripe/src/stripe-helpers.c
index ed7ed1a0b79..dcd2022f7f2 100644
--- a/xlators/cluster/stripe/src/stripe-helpers.c
+++ b/xlators/cluster/stripe/src/stripe-helpers.c
@@ -440,7 +440,6 @@ set_stripe_block_size (xlator_t *this, stripe_private_t *priv, char *data)
                 stripe_opt = GF_CALLOC (1, sizeof (struct stripe_options),
                                         gf_stripe_mt_stripe_options);
                 if (!stripe_opt) {
-                        GF_FREE (dup_str);
                         goto out;
                 }
 
@@ -486,10 +485,15 @@ set_stripe_block_size (xlator_t *this, stripe_private_t *priv, char *data)
 
                 stripe_str = strtok_r (NULL, ",", &tmp_str);
                 GF_FREE (dup_str);
+                dup_str = NULL;
         }
 
         ret = 0;
 out:
+
+        if (dup_str)
+                GF_FREE (dup_str);
+
         return ret;
 }
 
diff --git a/xlators/cluster/stripe/src/stripe.c b/xlators/cluster/stripe/src/stripe.c
index 86cc66f59c1..627e17dca77 100644
--- a/xlators/cluster/stripe/src/stripe.c
+++ b/xlators/cluster/stripe/src/stripe.c
@@ -4470,7 +4470,7 @@ stripe_vgetxattr_cbk (call_frame_t *frame, void *cookie,
         local = frame->local;
         cky = (long) cookie;
 
-        if (!local->xsel) {
+        if (local->xsel[0] == '\0') {
                 gf_log (this->name, GF_LOG_ERROR, "Empty xattr in cbk");
                 return ret;
         }
diff --git a/xlators/debug/trace/src/trace.c b/xlators/debug/trace/src/trace.c
index aada90d3824..d9c292c0104 100644
--- a/xlators/debug/trace/src/trace.c
+++ b/xlators/debug/trace/src/trace.c
@@ -473,6 +473,9 @@ trace_rename_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                                 preoldparentstr, postoldparentstr,
                                 prenewparentstr, postnewparentstr);
 
+                        if (statstr)
+                                GF_FREE (statstr);
+
                         if (preoldparentstr)
                                 GF_FREE (preoldparentstr);
 
diff --git a/xlators/features/index/src/index.c b/xlators/features/index/src/index.c
index ead20e06f88..8f630f2f94e 100644
--- a/xlators/features/index/src/index.c
+++ b/xlators/features/index/src/index.c
@@ -1079,6 +1079,9 @@ init (xlator_t *this)
         }
         ret = 0;
 out:
+        if (!this->private && priv)
+                GF_FREE (priv);
+
         return ret;
 }
 
diff --git a/xlators/features/quota/src/quota.c b/xlators/features/quota/src/quota.c
index f6c4e0099b9..436fb1b1cb1 100644
--- a/xlators/features/quota/src/quota.c
+++ b/xlators/features/quota/src/quota.c
@@ -497,6 +497,9 @@ quota_get_limit_value (inode_t *inode, xlator_t *this, int64_t *n)
         }
 
 out:
+        if (path)
+                GF_FREE (path);
+
         return ret;
 }
 
diff --git a/xlators/lib/src/libxlator.c b/xlators/lib/src/libxlator.c
index fe11e35b56d..195bd523663 100644
--- a/xlators/lib/src/libxlator.c
+++ b/xlators/lib/src/libxlator.c
@@ -187,12 +187,13 @@ out:
                 frame->local = local->xl_local;
                 local->xl_specf_unwind (frame, op_ret,
                                         op_errno, dict, xdata);
-                return 0;
         } else if (need_unwind) {
                 STACK_UNWIND_STRICT (getxattr, frame, op_ret, op_errno,
                                      dict, xdata);
         }
 
+        if (marker_xattr)
+                GF_FREE (marker_xattr);
         return 0;
 
 }
diff --git a/xlators/mgmt/glusterd/src/glusterd-geo-rep.c b/xlators/mgmt/glusterd/src/glusterd-geo-rep.c
index 4dc9396668d..c373fc14f1f 100644
--- a/xlators/mgmt/glusterd/src/glusterd-geo-rep.c
+++ b/xlators/mgmt/glusterd/src/glusterd-geo-rep.c
@@ -524,7 +524,7 @@ gsync_status (char *master, char *slave, int *status)
         int  fd                = -1;
 
         fd = gsyncd_getpidfile (master, slave, pidfile);
-        if (fd == -2)
+        if ((fd == -2) || (fd == -1))
                 return -1;
 
         *status = gsync_status_byfd (fd);
@@ -1118,7 +1118,7 @@ stop_gsync (char *master, char *slave, char **msg)
         GF_ASSERT (THIS->private);
 
         pfd = gsyncd_getpidfile (master, slave, pidfile);
-        if (pfd == -2) {
+        if ((pfd == -2) || (pfd == -1)) {
                 gf_log ("", GF_LOG_ERROR, GEOREP" stop validation "
                         " failed for %s & %s", master, slave);
                 ret = -1;
@@ -1160,7 +1160,8 @@ stop_gsync (char *master, char *slave, char **msg)
         ret = 0;
 
 out:
-        close (pfd);
+        if ((pfd != -2) && (pfd != -1))
+                close (pfd);
         return ret;
 }
 
@@ -1652,7 +1653,7 @@ glusterd_get_pid_from_file (char *master, char *slave, pid_t *pid)
 
         pfd = gsyncd_getpidfile (master, slave, pidfile);
 
-        if (pfd == -2) {
+        if ((pfd == -2) || (pfd == -1)) {
                 gf_log ("", GF_LOG_ERROR, GEOREP" log-rotate validation "
                         " failed for %s & %s", master, slave);
                 goto out;
@@ -1669,12 +1670,13 @@ glusterd_get_pid_from_file (char *master, char *slave, pid_t *pid)
                 goto out;
         }
 
-        close(pfd);
 
         *pid = strtol (buff, NULL, 10);
         ret = 0;
 
- out:
+out:
+        if ((pfd != -2) && (pfd != -1))
+                close(pfd);
         return ret;
 }
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-handler.c b/xlators/mgmt/glusterd/src/glusterd-handler.c
index 6ea40bc4d6c..d7ac4fd4f2c 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handler.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handler.c
@@ -83,8 +83,10 @@ glusterd_handle_friend_req (rpcsvc_request_t *req, uuid_t  uuid,
         if (ret) {
                 ret = glusterd_xfer_friend_add_resp (req, rhost, port, -1,
                                                      GF_PROBE_UNKNOWN_PEER);
-                if (friend_req->vols.vols_val)
+                if (friend_req->vols.vols_val) {
                         free (friend_req->vols.vols_val);
+                        friend_req->vols.vols_val = NULL;
+                }
                 goto out;
         }
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-handshake.c b/xlators/mgmt/glusterd/src/glusterd-handshake.c
index 64945a716c4..d80cacc8afd 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handshake.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handshake.c
@@ -209,13 +209,13 @@ fail:
                 rsp.op_errno = cookie;
 
         if (!rsp.spec)
-                rsp.spec = "";
+                rsp.spec = strdup ("");
 
         glusterd_submit_reply (req, &rsp, NULL, 0, NULL,
                                (xdrproc_t)xdr_gf_getspec_rsp);
         if (args.key)
                 free (args.key);//malloced by xdr
-        if (rsp.spec && (strcmp (rsp.spec, "")))
+        if (rsp.spec)
                 free (rsp.spec);
 
         return 0;
diff --git a/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c b/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c
index ddc4d1f492d..a7ccda71f72 100644
--- a/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c
+++ b/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c
@@ -837,7 +837,9 @@ glusterd3_1_stage_op_cbk (struct rpc_req *req, struct iovec *iov,
         if (-1 == req->rpc_status) {
                 rsp.op_ret   = -1;
                 rsp.op_errno = EINVAL;
-                rsp.op_errstr = "error";
+                /* use standard allocation because to keep uniformity
+                   in freeing it */
+                rsp.op_errstr = strdup ("error");
                 goto out;
         }
 
@@ -846,7 +848,9 @@ glusterd3_1_stage_op_cbk (struct rpc_req *req, struct iovec *iov,
                 gf_log ("", GF_LOG_ERROR, "error");
                 rsp.op_ret   = -1;
                 rsp.op_errno = EINVAL;
-                rsp.op_errstr = "error";
+                /* use standard allocation because to keep uniformity
+                   in freeing it */
+                rsp.op_errstr = strdup ("xdr decoding failed");
                 goto out;
         }
 
@@ -918,7 +922,7 @@ out:
                 glusterd_op_sm ();
         }
 
-        if (rsp.op_errstr && strcmp (rsp.op_errstr, "error"))
+        if (rsp.op_errstr)
                 free (rsp.op_errstr); //malloced by xdr
         if (dict) {
                 if (!dict->extra_stdfree && rsp.dict.dict_val)
@@ -1268,17 +1272,21 @@ glusterd3_1_commit_op_cbk (struct rpc_req *req, struct iovec *iov,
         if (-1 == req->rpc_status) {
                 rsp.op_ret   = -1;
                 rsp.op_errno = EINVAL;
-                rsp.op_errstr = "error";
+                /* use standard allocation because to keep uniformity
+                   in freeing it */
+                rsp.op_errstr = strdup ("error");
 		event_type = GD_OP_EVENT_RCVD_RJT;
                 goto out;
         }
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gd1_mgmt_commit_op_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log ("", GF_LOG_ERROR, "xdr decoding error");
                 rsp.op_ret   = -1;
                 rsp.op_errno = EINVAL;
-                rsp.op_errstr = "error";
+                /* use standard allocation because to keep uniformity
+                   in freeing it */
+                rsp.op_errstr = strdup ("xdr decoding error");
 		event_type = GD_OP_EVENT_RCVD_RJT;
                 goto out;
         }
@@ -1395,7 +1403,7 @@ out:
 
         if (dict)
                 dict_unref (dict);
-        if (rsp.op_errstr && strcmp (rsp.op_errstr, "error"))
+        if (rsp.op_errstr)
                 free (rsp.op_errstr); //malloced by xdr
         GLUSTERD_STACK_DESTROY (((call_frame_t *)myframe));
         return ret;
@@ -1788,7 +1796,9 @@ glusterd3_1_brick_op_cbk (struct rpc_req *req, struct iovec *iov,
         if (-1 == req->rpc_status) {
                 rsp.op_ret   = -1;
                 rsp.op_errno = EINVAL;
-                rsp.op_errstr = "error";
+                /* use standard allocation because to keep uniformity
+                   in freeing it */
+                rsp.op_errstr = strdup ("error");
 		event_type = GD_OP_EVENT_RCVD_RJT;
                 goto out;
         }
@@ -1857,7 +1867,7 @@ out:
 
         if (ret && dict)
                 dict_unref (dict);
-        if (rsp.op_errstr && strcmp (rsp.op_errstr, "error"))
+        if (rsp.op_errstr)
                 free (rsp.op_errstr); //malloced by xdr
         GLUSTERD_STACK_DESTROY (frame);
         return ret;
diff --git a/xlators/mgmt/glusterd/src/glusterd-store.c b/xlators/mgmt/glusterd/src/glusterd-store.c
index 56c1d98754a..076520bf936 100644
--- a/xlators/mgmt/glusterd/src/glusterd-store.c
+++ b/xlators/mgmt/glusterd/src/glusterd-store.c
@@ -1077,12 +1077,17 @@ glusterd_store_retrieve_value (glusterd_store_handle_t *handle,
 
         handle->fd = open (handle->path, O_RDWR);
 
+        if (handle->fd == -1) {
+                gf_log ("", GF_LOG_ERROR, "Unable to open file %s errno: %s",
+                        handle->path, strerror (errno));
+                goto out;
+        }
         if (!handle->read)
                 handle->read = fdopen (handle->fd, "r");
 
         if (!handle->read) {
-                gf_log ("", GF_LOG_ERROR, "Unable to open file %s errno: %d",
-                        handle->path, errno);
+                gf_log ("", GF_LOG_ERROR, "Unable to open file %s errno: %s",
+                        handle->path, strerror (errno));
                 goto out;
         }
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-utils.c b/xlators/mgmt/glusterd/src/glusterd-utils.c
index 1eaed4e383c..ed7ba1d51e6 100644
--- a/xlators/mgmt/glusterd/src/glusterd-utils.c
+++ b/xlators/mgmt/glusterd/src/glusterd-utils.c
@@ -300,7 +300,7 @@ glusterd_unlock (uuid_t uuid)
 
         glusterd_get_lock_owner (&owner);
 
-        if (NULL == owner) {
+        if (uuid_is_null (owner)) {
                 gf_log ("glusterd", GF_LOG_ERROR, "Cluster lock not held!");
                 goto out;
         }
diff --git a/xlators/mgmt/glusterd/src/glusterd-volgen.c b/xlators/mgmt/glusterd/src/glusterd-volgen.c
index dea139ebc2b..f7d17f00d0e 100644
--- a/xlators/mgmt/glusterd/src/glusterd-volgen.c
+++ b/xlators/mgmt/glusterd/src/glusterd-volgen.c
@@ -2569,7 +2569,7 @@ nfs_option_handler (volgen_graph_t *graph,
 
                 ret = xlator_set_option (xl, vme->key, vme->value);
         }*/
-        if ( !volinfo || !volinfo->volname)
+        if (!volinfo || (volinfo->volname[0] == '\0'))
                 return 0;
 
         if (! strcmp (vme->option, "!rpc-auth.addr.*.allow")) {
diff --git a/xlators/mgmt/glusterd/src/glusterd.c b/xlators/mgmt/glusterd/src/glusterd.c
index 7f41721c0a2..6acf3daffce 100644
--- a/xlators/mgmt/glusterd/src/glusterd.c
+++ b/xlators/mgmt/glusterd/src/glusterd.c
@@ -650,9 +650,12 @@ check_prepare_mountbroker_root (char *mountbroker_root)
         ret = 0;
 
  out:
-        close (dfd0);
-        close (dfd);
-        close (dfd2);
+        if (dfd0 != -1)
+                close (dfd0);
+        if (dfd != -1)
+                close (dfd);
+        if (dfd2 != -1)
+                close (dfd2);
 
         return ret;
 }
diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c
index c06da7eec58..9a2d60b9b4c 100644
--- a/xlators/mount/fuse/src/fuse-bridge.c
+++ b/xlators/mount/fuse/src/fuse-bridge.c
@@ -4601,8 +4601,10 @@ cleanup_exit:
                 GF_FREE (fsname);
         if (priv) {
                 GF_FREE (priv->mount_point);
-                close (priv->fd);
-                close (priv->fuse_dump_fd);
+                if (priv->fd != -1)
+                        close (priv->fd);
+                if (priv->fuse_dump_fd != -1)
+                        close (priv->fuse_dump_fd);
                 GF_FREE (priv);
         }
         if (mnt_args)
diff --git a/xlators/mount/fuse/src/fuse-helpers.c b/xlators/mount/fuse/src/fuse-helpers.c
index 452a4819441..fbff1e39a0c 100644
--- a/xlators/mount/fuse/src/fuse-helpers.c
+++ b/xlators/mount/fuse/src/fuse-helpers.c
@@ -392,6 +392,10 @@ fuse_loc_fill (loc_t *loc, fuse_state_t *state, ino_t ino,
         }
         ret = 0;
 fail:
+        /* this should not happen as inode_path returns -1 when buf is NULL
+           for sure */
+        if (path && !loc->path)
+                GF_FREE (path);
         return ret;
 }
 
diff --git a/xlators/performance/io-threads/src/io-threads.c b/xlators/performance/io-threads/src/io-threads.c
index 66864fcd438..04abac7ad31 100644
--- a/xlators/performance/io-threads/src/io-threads.c
+++ b/xlators/performance/io-threads/src/io-threads.c
@@ -2489,9 +2489,9 @@ out:
 int
 init (xlator_t *this)
 {
-        iot_conf_t      *conf = NULL;
-        int              ret = -1;
-        int              i = 0;
+        iot_conf_t *conf = NULL;
+        int         ret  = -1;
+        int         i    = 0;
 
 	if (!this->children || this->children->next) {
 		gf_log ("io-threads", GF_LOG_ERROR,
@@ -2553,13 +2553,15 @@ init (xlator_t *this)
         if (ret == -1) {
                 gf_log (this->name, GF_LOG_ERROR,
                         "cannot initialize worker threads, exiting init");
-                GF_FREE (conf);
                 goto out;
         }
 
 	this->private = conf;
         ret = 0;
 out:
+        if (ret)
+                GF_FREE (conf);
+
 	return ret;
 }
 
diff --git a/xlators/protocol/client/src/client-handshake.c b/xlators/protocol/client/src/client-handshake.c
index 944b9ca80b2..a3cb325b02a 100644
--- a/xlators/protocol/client/src/client-handshake.c
+++ b/xlators/protocol/client/src/client-handshake.c
@@ -1369,8 +1369,7 @@ client_setvolume_cbk (struct rpc_req *req, struct iovec *iov, int count, void *m
                         remote_error ? remote_error : strerror (op_errno));
                 errno = op_errno;
                 if (remote_error &&
-                   (strncmp ("Authentication failed",remote_error,
-                             sizeof (remote_error)) == 0)) {
+                    (strcmp ("Authentication failed", remote_error) == 0)) {
                         auth_fail = _gf_true;
                         op_ret = 0;
                 }
diff --git a/xlators/protocol/server/src/authenticate.c b/xlators/protocol/server/src/authenticate.c
index de5bf9f437b..ffadf2e4d67 100644
--- a/xlators/protocol/server/src/authenticate.c
+++ b/xlators/protocol/server/src/authenticate.c
@@ -34,12 +34,12 @@
 static void
 init (dict_t *this, char *key, data_t *value, void *data)
 {
-        void *handle = NULL;
-        char *auth_file = NULL;
-        auth_handle_t *auth_handle = NULL;
-        auth_fn_t authenticate = NULL;
-        int *error = NULL;
-        int  ret = 0;
+        void          *handle       = NULL;
+        char          *auth_file    = NULL;
+        auth_handle_t *auth_handle  = NULL;
+        auth_fn_t      authenticate = NULL;
+        int           *error        = NULL;
+        int            ret          = 0;
 
         /* It gets over written */
         error = data;
@@ -78,6 +78,7 @@ init (dict_t *this, char *key, data_t *value, void *data)
                 gf_log ("authenticate", GF_LOG_ERROR,
                         "dlsym(gf_auth) on %s\n", dlerror ());
                 dict_set (this, key, data_from_dynptr (NULL, 0));
+                dlclose (handle);
                 *error = -1;
                 return;
         }
@@ -87,10 +88,17 @@ init (dict_t *this, char *key, data_t *value, void *data)
         if (!auth_handle) {
                 dict_set (this, key, data_from_dynptr (NULL, 0));
                 *error = -1;
+                dlclose (handle);
                 return;
         }
         auth_handle->vol_opt = GF_CALLOC (1, sizeof (volume_opt_list_t),
                                           gf_common_mt_volume_opt_list_t);
+        if (!auth_handle->vol_opt) {
+                dict_set (this, key, data_from_dynptr (NULL, 0));
+                *error = -1;
+                dlclose (handle);
+                return;
+        }
         auth_handle->vol_opt->given_opt = dlsym (handle, "options");
         if (auth_handle->vol_opt->given_opt == NULL) {
                 gf_log ("authenticate", GF_LOG_DEBUG,
diff --git a/xlators/storage/posix/src/posix.c b/xlators/storage/posix/src/posix.c
index c218a673548..2f9b475abc1 100644
--- a/xlators/storage/posix/src/posix.c
+++ b/xlators/storage/posix/src/posix.c
@@ -1032,15 +1032,15 @@ int32_t
 posix_unlink (call_frame_t *frame, xlator_t *this,
               loc_t *loc, int xflag, dict_t *xdata)
 {
-        int32_t                  op_ret    = -1;
-        int32_t                  op_errno  = 0;
-        char                    *real_path = NULL;
-        char                    *par_path = NULL;
-        int32_t                  fd = -1;
-        struct iatt            stbuf;
-        struct posix_private    *priv      = NULL;
-        struct iatt            preparent = {0,};
-        struct iatt            postparent = {0,};
+        int32_t               op_ret     = -1;
+        int32_t               op_errno   = 0;
+        char                 *real_path  = NULL;
+        char                 *par_path   = NULL;
+        int32_t               fd         = -1;
+        struct iatt           stbuf      = {0,};
+        struct posix_private *priv       = NULL;
+        struct iatt           preparent  = {0,};
+        struct iatt           postparent = {0,};
 
         DECLARE_OLD_FS_ID_VAR;
 
@@ -3748,27 +3748,22 @@ int32_t
 posix_rchecksum (call_frame_t *frame, xlator_t *this,
                  fd_t *fd, off_t offset, int32_t len, dict_t *xdata)
 {
-        char *buf = NULL;
-
-        int       _fd      = -1;
-
-        struct posix_fd *pfd  = NULL;
-
-        int op_ret   = -1;
-        int op_errno = 0;
-
-        int ret = 0;
-
-        int32_t weak_checksum = 0;
-        unsigned char strong_checksum[MD5_DIGEST_LENGTH];
+        char            *buf           = NULL;
+        int              _fd           = -1;
+        struct posix_fd *pfd           = NULL;
+        int              op_ret        = -1;
+        int              op_errno      = 0;
+        int              ret           = 0;
+        int32_t          weak_checksum = 0;
+        unsigned char    strong_checksum[MD5_DIGEST_LENGTH];
 
         VALIDATE_OR_GOTO (frame, out);
         VALIDATE_OR_GOTO (this, out);
         VALIDATE_OR_GOTO (fd, out);
 
         memset (strong_checksum, 0, MD5_DIGEST_LENGTH);
-        buf = GF_CALLOC (1, len, gf_posix_mt_char);
 
+        buf = GF_CALLOC (1, len, gf_posix_mt_char);
         if (!buf) {
                 op_errno = ENOMEM;
                 goto out;
@@ -3797,12 +3792,14 @@ posix_rchecksum (call_frame_t *frame, xlator_t *this,
         weak_checksum = gf_rsync_weak_checksum ((unsigned char *) buf, (size_t) len);
         gf_rsync_strong_checksum ((unsigned char *) buf, (size_t) len, (unsigned char *) strong_checksum);
 
-        GF_FREE (buf);
-
         op_ret = 0;
 out:
         STACK_UNWIND_STRICT (rchecksum, frame, op_ret, op_errno,
                              weak_checksum, strong_checksum, NULL);
+
+        if (buf)
+                GF_FREE (buf);
+
         return 0;
 }