storage: skip selinux cleanup when fd not available

When attempting to backport gluster pools to an older versoin
where there is no VIR_STRDUP, I got a crash from calling
strdup(,NULL). Rather than relying on the current else branch
safely doing nothing when there is no fd, it is easier to just
skip it. While at it, there's no need to explicitly set
perms.label to NULL after a VIR_FREE().

* src/storage/storage_backend.c
(virStorageBackendUpdateVolTargetInfoFD): Minor optimization.

Signed-off-by: Eric Blake <eblake@redhat.com>

diff --git a/src/storage/storage_backend.c b/src/storage/storage_backend.c
index bde39d6c2fb18455db0c9fff034767c1e901368c..b08d646bb34b9dc17abadd0c57e73c9ea9a0d34d 100644 (file)
--- a/src/storage/storage_backend.c
+++ b/src/storage/storage_backend.c
@@ -1385,24 +1385,22 @@ virStorageBackendUpdateVolTargetInfoFD(virStorageVolTargetPtr target,
 
 #if WITH_SELINUX
     /* XXX: make this a security driver call */
-    if (fd >= 0 && fgetfilecon_raw(fd, &filecon) == -1) {
-        if (errno != ENODATA && errno != ENOTSUP) {
-            virReportSystemError(errno,
-                                 _("cannot get file context of '%s'"),
-                                 target->path);
-            return -1;
+    if (fd >= 0) {
+        if (fgetfilecon_raw(fd, &filecon) == -1) {
+            if (errno != ENODATA && errno != ENOTSUP) {
+                virReportSystemError(errno,
+                                     _("cannot get file context of '%s'"),
+                                     target->path);
+                return -1;
+            }
         } else {
-            target->perms.label = NULL;
-        }
-    } else {
-        if (VIR_STRDUP(target->perms.label, filecon) < 0) {
+            if (VIR_STRDUP(target->perms.label, filecon) < 0) {
+                freecon(filecon);
+                return -1;
+            }
             freecon(filecon);
-            return -1;
         }
-        freecon(filecon);
     }
-#else
-    target->perms.label = NULL;
 #endif
 
     return 0;