From 1b7b533f65db9b31f76972b2899ec7ec6433ae77 Mon Sep 17 00:00:00 2001 From: Richard Guy Briggs Date: Mon, 2 Dec 2013 11:33:01 -0500 Subject: [PATCH] audit: drop audit_cmd_lock in AUDIT_USER family of cases We do not need to hold the audit_cmd_mutex for this family of cases. The possible exception to this is the call to audit_filter_user(), so drop the lock immediately after. To help in fixing the race we are trying to avoid, make sure that nothing called by audit_filter_user() calls audit_log_start(). In particular, watch out for *_audit_rule_match(). This fix will take care of systemd and anything USING audit. It still means that we could race with something configuring audit and auditd shutting down. Signed-off-by: Richard Guy Briggs Reported-by: toshi.okajima@jp.fujitsu.com Tested-by: toshi.okajima@jp.fujitsu.com Signed-off-by: Eric Paris --- kernel/audit.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/kernel/audit.c b/kernel/audit.c index ce8514f9aa6c..c05b6027e874 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -876,6 +876,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) if (err) break; } + mutex_unlock(&audit_cmd_mutex); audit_log_common_recv_msg(&ab, msg_type); if (msg_type != AUDIT_USER_TTY) audit_log_format(ab, " msg='%.*s'", @@ -893,6 +894,7 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) } audit_set_portid(ab, NETLINK_CB(skb).portid); audit_log_end(ab); + mutex_lock(&audit_cmd_mutex); } break; case AUDIT_ADD_RULE: