netlabel: Less function calls in netlbl_mgmt_add_common() after error detection

The functions "cipso_v4_doi_putdef" and "kfree" could be called in some cases
by the netlbl_mgmt_add_common() function during error handling even if the
passed variables contained still a null pointer.

* This implementation detail could be improved by adjustments for jump labels.

* Let us return immediately after the first failed function call according to
  the current Linux coding style convention.

* Let us delete also an unnecessary check for the variable "entry" there.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 25 deletions

diff --git a/net/netlabel/netlabel_mgmt.c b/net/netlabel/netlabel_mgmt.c
index f5807f57aebc..70440748fe5c 100644
--- a/net/netlabel/netlabel_mgmt.c
+++ b/net/netlabel/netlabel_mgmt.c
@@ -93,23 +93,20 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                                   struct netlbl_audit *audit_info)
 {
         int ret_val = -EINVAL;
-        struct netlbl_dom_map *entry = NULL;
         struct netlbl_domaddr_map *addrmap = NULL;
         struct cipso_v4_doi *cipsov4 = NULL;
         u32 tmp_val;
+        struct netlbl_dom_map *entry = kzalloc(sizeof(*entry), GFP_KERNEL);
 
-        entry = kzalloc(sizeof(*entry), GFP_KERNEL);
-        if (entry == NULL) {
-                ret_val = -ENOMEM;
-                goto add_failure;
-        }
+        if (!entry)
+                return -ENOMEM;
         entry->def.type = nla_get_u32(info->attrs[NLBL_MGMT_A_PROTOCOL]);
         if (info->attrs[NLBL_MGMT_A_DOMAIN]) {
                 size_t tmp_size = nla_len(info->attrs[NLBL_MGMT_A_DOMAIN]);
                 entry->domain = kmalloc(tmp_size, GFP_KERNEL);
                 if (entry->domain == NULL) {
                         ret_val = -ENOMEM;
-                        goto add_failure;
+                        goto add_free_entry;
                 }
                 nla_strlcpy(entry->domain,
                             info->attrs[NLBL_MGMT_A_DOMAIN], tmp_size);
@@ -125,16 +122,16 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 break;
         case NETLBL_NLTYPE_CIPSOV4:
                 if (!info->attrs[NLBL_MGMT_A_CV4DOI])
-                        goto add_failure;
+                        goto add_free_domain;
 
                 tmp_val = nla_get_u32(info->attrs[NLBL_MGMT_A_CV4DOI]);
                 cipsov4 = cipso_v4_doi_getdef(tmp_val);
                 if (cipsov4 == NULL)
-                        goto add_failure;
+                        goto add_free_domain;
                 entry->def.cipso = cipsov4;
                 break;
         default:
-                goto add_failure;
+                goto add_free_domain;
         }
 
         if (info->attrs[NLBL_MGMT_A_IPV4ADDR]) {
@@ -145,7 +142,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL);
                 if (addrmap == NULL) {
                         ret_val = -ENOMEM;
-                        goto add_failure;
+                        goto add_doi_put_def;
                 }
                 INIT_LIST_HEAD(&addrmap->list4);
                 INIT_LIST_HEAD(&addrmap->list6);
@@ -153,12 +150,12 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV4ADDR]) !=
                     sizeof(struct in_addr)) {
                         ret_val = -EINVAL;
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV4MASK]) !=
                     sizeof(struct in_addr)) {
                         ret_val = -EINVAL;
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
                 addr = nla_data(info->attrs[NLBL_MGMT_A_IPV4ADDR]);
                 mask = nla_data(info->attrs[NLBL_MGMT_A_IPV4MASK]);
@@ -166,7 +163,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 map = kzalloc(sizeof(*map), GFP_KERNEL);
                 if (map == NULL) {
                         ret_val = -ENOMEM;
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
                 map->list.addr = addr->s_addr & mask->s_addr;
                 map->list.mask = mask->s_addr;
@@ -178,7 +175,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 ret_val = netlbl_af4list_add(&map->list, &addrmap->list4);
                 if (ret_val != 0) {
                         kfree(map);
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
 
                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
@@ -192,7 +189,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 addrmap = kzalloc(sizeof(*addrmap), GFP_KERNEL);
                 if (addrmap == NULL) {
                         ret_val = -ENOMEM;
-                        goto add_failure;
+                        goto add_doi_put_def;
                 }
                 INIT_LIST_HEAD(&addrmap->list4);
                 INIT_LIST_HEAD(&addrmap->list6);
@@ -200,12 +197,12 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV6ADDR]) !=
                     sizeof(struct in6_addr)) {
                         ret_val = -EINVAL;
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
                 if (nla_len(info->attrs[NLBL_MGMT_A_IPV6MASK]) !=
                     sizeof(struct in6_addr)) {
                         ret_val = -EINVAL;
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
                 addr = nla_data(info->attrs[NLBL_MGMT_A_IPV6ADDR]);
                 mask = nla_data(info->attrs[NLBL_MGMT_A_IPV6MASK]);
@@ -213,7 +210,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 map = kzalloc(sizeof(*map), GFP_KERNEL);
                 if (map == NULL) {
                         ret_val = -ENOMEM;
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
                 map->list.addr = *addr;
                 map->list.addr.s6_addr32[0] &= mask->s6_addr32[0];
@@ -227,7 +224,7 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
                 ret_val = netlbl_af6list_add(&map->list, &addrmap->list6);
                 if (ret_val != 0) {
                         kfree(map);
-                        goto add_failure;
+                        goto add_free_addrmap;
                 }
 
                 entry->def.type = NETLBL_NLTYPE_ADDRSELECT;
@@ -237,15 +234,17 @@ static int netlbl_mgmt_add_common(struct genl_info *info,
 
         ret_val = netlbl_domhsh_add(entry, audit_info);
         if (ret_val != 0)
-                goto add_failure;
+                goto add_free_addrmap;
 
         return 0;
 
-add_failure:
-        cipso_v4_doi_putdef(cipsov4);
-        if (entry)
-                kfree(entry->domain);
+add_free_addrmap:
         kfree(addrmap);
+add_doi_put_def:
+        cipso_v4_doi_putdef(cipsov4);
+add_free_domain:
+        kfree(entry->domain);
+add_free_entry:
         kfree(entry);
         return ret_val;
 }