{"id":810378,"url":"http://patchwork.ozlabs.org/api/patches/810378/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/patch/1217baf9faf9d034ba8224cb6362b822c51a0eae.1504669632.git.lucien.xin@gmail.com/","project":{"id":7,"url":"http://patchwork.ozlabs.org/api/projects/7/?format=json","name":"Linux network development","link_name":"netdev","list_id":"netdev.vger.kernel.org","list_email":"netdev@vger.kernel.org","web_url":null,"scm_url":null,"webscm_url":null,"list_archive_url":"","list_archive_url_format":"","commit_url_format":""},"msgid":"<1217baf9faf9d034ba8224cb6362b822c51a0eae.1504669632.git.lucien.xin@gmail.com>","list_archive_url":null,"date":"2017-09-06T03:47:12","name":"[net] netlink: fix an use-after-free issue for nlk groups","commit_ref":null,"pull_url":null,"state":"accepted","archived":true,"hash":"7df283c5c2e390f76a94d1a66f4c70d589aeebe6","submitter":{"id":61073,"url":"http://patchwork.ozlabs.org/api/people/61073/?format=json","name":"Xin Long","email":"lucien.xin@gmail.com"},"delegate":{"id":34,"url":"http://patchwork.ozlabs.org/api/users/34/?format=json","username":"davem","first_name":"David","last_name":"Miller","email":"davem@davemloft.net"},"mbox":"http://patchwork.ozlabs.org/project/netdev/patch/1217baf9faf9d034ba8224cb6362b822c51a0eae.1504669632.git.lucien.xin@gmail.com/mbox/","series":[{"id":1685,"url":"http://patchwork.ozlabs.org/api/series/1685/?format=json","web_url":"http://patchwork.ozlabs.org/project/netdev/list/?series=1685","date":"2017-09-06T03:47:12","name":"[net] netlink: fix an use-after-free issue for nlk groups","version":1,"mbox":"http://patchwork.ozlabs.org/series/1685/mbox/"}],"comments":"http://patchwork.ozlabs.org/api/patches/810378/comments/","check":"pending","checks":"http://patchwork.ozlabs.org/api/patches/810378/checks/","tags":{},"related":[],"headers":{"Return-Path":"","X-Original-To":"patchwork-incoming@ozlabs.org","Delivered-To":"patchwork-incoming@ozlabs.org","Authentication-Results":["ozlabs.org;\n\tspf=none (mailfrom) smtp.mailfrom=vger.kernel.org\n\t(client-ip=209.132.180.67; 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The similar issue also\nexists in netlink_seq_show().\n\nThis patch is to defer nlk groups' free in deferred_put_nlk_sk.\n\nReported-by: ChunYu Wang \nAcked-by: Florian Westphal \nSigned-off-by: Xin Long \n---\n net/netlink/af_netlink.c | 6 +++---\n 1 file changed, 3 insertions(+), 3 deletions(-)","diff":"diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c\nindex 5acee49..94a61e6 100644\n--- a/net/netlink/af_netlink.c\n+++ b/net/netlink/af_netlink.c\n@@ -691,6 +691,9 @@ static void deferred_put_nlk_sk(struct rcu_head *head)\n \tstruct netlink_sock *nlk = container_of(head, struct netlink_sock, rcu);\n \tstruct sock *sk = &nlk->sk;\n \n+\tkfree(nlk->groups);\n+\tnlk->groups = NULL;\n+\n \tif (!refcount_dec_and_test(&sk->sk_refcnt))\n \t\treturn;\n \n@@ -769,9 +772,6 @@ static int netlink_release(struct socket *sock)\n \t\tnetlink_table_ungrab();\n \t}\n \n-\tkfree(nlk->groups);\n-\tnlk->groups = NULL;\n-\n \tlocal_bh_disable();\n \tsock_prot_inuse_add(sock_net(sk), &netlink_proto, -1);\n \tlocal_bh_enable();\n","prefixes":["net"]}