From: Shu Wang Date: Tue, 18 Jul 2017 06:37:24 +0000 (+0800) Subject: audit: fix memleak in auditd_send_unicast_skb. X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=b0659ae5e30074ede1dc08f2c6d64f0c11d64e0f;p=openwrt%2Fstaging%2Fblogic.git audit: fix memleak in auditd_send_unicast_skb. Found this issue by kmemleak report, auditd_send_unicast_skb did not free skb if rcu_dereference(auditd_conn) returns null. unreferenced object 0xffff88082568ce00 (size 256): comm "auditd", pid 1119, jiffies 4294708499 backtrace: [] kmemleak_alloc+0x4a/0xa0 [] kmem_cache_alloc_node+0xcc/0x210 [] __alloc_skb+0x5d/0x290 [] audit_make_reply+0x54/0xd0 [] audit_receive_msg+0x967/0xd70 ---------------- (gdb) list *audit_receive_msg+0x967 0xffffffff8113dff7 is in audit_receive_msg (kernel/audit.c:1133). 1132 skb = audit_make_reply(0, AUDIT_REPLACE, 0, 0, &pvnr, sizeof(pvnr)); --------------- [] audit_receive+0x52/0xa0 [] netlink_unicast+0x181/0x240 [] netlink_sendmsg+0x2c2/0x3b0 [] sock_sendmsg+0x38/0x50 [] SYSC_sendto+0x102/0x190 [] SyS_sendto+0xe/0x10 [] entry_SYSCALL_64_fastpath+0x1a/0xa5 [] 0xffffffffffffffff Signed-off-by: Shu Wang Signed-off-by: Paul Moore --- diff --git a/kernel/audit.c b/kernel/audit.c index 7cad70214b81..07def5e49cc9 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -641,6 +641,7 @@ static int auditd_send_unicast_skb(struct sk_buff *skb) ac = rcu_dereference(auditd_conn); if (!ac) { rcu_read_unlock(); + kfree_skb(skb); rc = -ECONNREFUSED; goto err; }