[PATCH 2/2] net/netlabel: Avoid call to genlmsg_cancel
From: Julia Lawall <hidden>
Date: 2011-01-28 13:57:40
Also in:
kernel-janitors, lkml
Subsystem:
networking [general], networking [labeled] (netlabel, labeled ipsec, secmark), the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Paul Moore, Linus Torvalds
genlmsg_cancel subtracts some constants from its second argument before calling nlmsg_cancel. nlmsg_cancel then calls nlmsg_trim on the same arguments. nlmsg_trim tests for NULL before doing any computation, but a NULL second argument to genlmsg_cancel is no longer NULL due to the initial subtraction. Nothing else happens in this execution, so the call to genlmsg_cancel is simply unnecessary in this case. The semantic match that finds this problem is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression data; @@ if (data == NULL) { ... * genlmsg_cancel(..., data); ... return ...; } // </smpl> Signed-off-by: Julia Lawall <redacted> --- net/netlabel/netlabel_cipso_v4.c | 2 +- net/netlabel/netlabel_mgmt.c | 4 ++-- net/netlabel/netlabel_unlabeled.c | 2 +- 3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/net/netlabel/netlabel_cipso_v4.c b/net/netlabel/netlabel_cipso_v4.c
index 5f14c84..0a1f77b 100644
--- a/net/netlabel/netlabel_cipso_v4.c
+++ b/net/netlabel/netlabel_cipso_v4.c@@ -635,7 +635,7 @@ static int netlbl_cipsov4_listall_cb(struct cipso_v4_doi *doi_def, void *arg) cb_arg->seq, &netlbl_cipsov4_gnl_family, NLM_F_MULTI, NLBL_CIPSOV4_C_LISTALL); if (data == NULL) - goto listall_cb_failure; + return ret_val; ret_val = nla_put_u32(cb_arg->skb, NLBL_CIPSOV4_A_DOI, doi_def->doi); if (ret_val != 0)
diff --git a/net/netlabel/netlabel_mgmt.c b/net/netlabel/netlabel_mgmt.c
index 998e85e..daaa01d 100644
--- a/net/netlabel/netlabel_mgmt.c
+++ b/net/netlabel/netlabel_mgmt.c@@ -452,7 +452,7 @@ static int netlbl_mgmt_listall_cb(struct netlbl_dom_map *entry, void *arg) cb_arg->seq, &netlbl_mgmt_gnl_family, NLM_F_MULTI, NLBL_MGMT_C_LISTALL); if (data == NULL) - goto listall_cb_failure; + return ret_val; ret_val = netlbl_mgmt_listentry(cb_arg->skb, entry); if (ret_val != 0)
@@ -617,7 +617,7 @@ static int netlbl_mgmt_protocols_cb(struct sk_buff *skb, &netlbl_mgmt_gnl_family, NLM_F_MULTI, NLBL_MGMT_C_PROTOCOLS); if (data == NULL) - goto protocols_cb_failure; + return ret_val; ret_val = nla_put_u32(skb, NLBL_MGMT_A_PROTOCOL, protocol); if (ret_val != 0)
diff --git a/net/netlabel/netlabel_unlabeled.c b/net/netlabel/netlabel_unlabeled.c
index e2b0a68..b5d3945 100644
--- a/net/netlabel/netlabel_unlabeled.c
+++ b/net/netlabel/netlabel_unlabeled.c@@ -1141,7 +1141,7 @@ static int netlbl_unlabel_staticlist_gen(u32 cmd, cb_arg->seq, &netlbl_unlabel_gnl_family, NLM_F_MULTI, cmd); if (data == NULL) - goto list_cb_failure; + return ret_val; if (iface->ifindex > 0) { dev = dev_get_by_index(&init_net, iface->ifindex);