Illumos 5518 - Memory leaks in libzfs import implementation

5518 Memory leaks in libzfs import implementation
Reviewed by: Dan Fields <dan.fields@nexenta.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Serghei Samsi <sscdvp@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/5518
  https://github.com/illumos/illumos-gate/commit/078266a

Porting notes:
- One hunk of this change was already applied independently in
  commit 4def05f.

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>

1 files changed, 14 insertions, 11 deletions

diff --git a/lib/libzfs/libzfs_pool.c b/lib/libzfs/libzfs_pool.c
index e603526f48d4..9a276d061d35 100644
--- a/lib/libzfs/libzfs_pool.c
+++ b/lib/libzfs/libzfs_pool.c
@@ -20,8 +20,8 @@
  */
 
 /*
+ * Copyright 2015 Nexenta Systems, Inc.  All rights reserved.
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
  * Copyright (c) 2011, 2014 by Delphix. All rights reserved.
  */
 
@@ -1783,7 +1783,7 @@ zpool_import_props(libzfs_handle_t *hdl, nvlist_t *config, const char *newname,
 		thename = origname;
 	}
 
-	if (props) {
+	if (props != NULL) {
 		uint64_t version;
 		prop_flags_t flags = { .create = B_FALSE, .import = B_TRUE };
 
@@ -1791,12 +1791,13 @@ zpool_import_props(libzfs_handle_t *hdl, nvlist_t *config, const char *newname,
 		    &version) == 0);
 
 		if ((props = zpool_valid_proplist(hdl, origname,
-		    props, version, flags, errbuf)) == NULL) {
+		    props, version, flags, errbuf)) == NULL)
 			return (-1);
-		} else if (zcmd_write_src_nvlist(hdl, &zc, props) != 0) {
+		if (zcmd_write_src_nvlist(hdl, &zc, props) != 0) {
 			nvlist_free(props);
 			return (-1);
 		}
+		nvlist_free(props);
 	}
 
 	(void) strlcpy(zc.zc_name, thename, sizeof (zc.zc_name));
@@ -1805,11 +1806,11 @@ zpool_import_props(libzfs_handle_t *hdl, nvlist_t *config, const char *newname,
 	    &zc.zc_guid) == 0);
 
 	if (zcmd_write_conf_nvlist(hdl, &zc, config) != 0) {
-		nvlist_free(props);
+		zcmd_free_nvlists(&zc);
 		return (-1);
 	}
 	if (zcmd_alloc_dst_nvlist(hdl, &zc, zc.zc_nvlist_conf_size * 2) != 0) {
-		nvlist_free(props);
+		zcmd_free_nvlists(&zc);
 		return (-1);
 	}
 
@@ -1825,6 +1826,9 @@ zpool_import_props(libzfs_handle_t *hdl, nvlist_t *config, const char *newname,
 		error = errno;
 
 	(void) zcmd_read_dst_nvlist(hdl, &zc, &nv);
+
+	zcmd_free_nvlists(&zc);
+
 	zpool_get_rewind_policy(config, &policy);
 
 	if (error) {
@@ -1936,9 +1940,6 @@ zpool_import_props(libzfs_handle_t *hdl, nvlist_t *config, const char *newname,
 		return (0);
 	}
 
-	zcmd_free_nvlists(&zc);
-	nvlist_free(props);
-
 	return (ret);
 }
 
@@ -3335,8 +3336,10 @@ devid_to_path(char *devid_str)
 	if (ret != 0)
 		return (NULL);
 
-	if ((path = strdup(list[0].devname)) == NULL)
-		return (NULL);
+	/*
+	 * In a case the strdup() fails, we will just return NULL below.
+	 */
+	path = strdup(list[0].devname);
 
 	devid_free_nmlist(list);