Re: [PATCH] Free skb at error context in auditd_send_unicast_skb().

I got following memory leak reports by kmemleak. unreferenced object 0xffff965962fa0600 (size 256): comm "auditd", pid 401, jiffies 4294671604 (age 62.331s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffffb8859baa>] kmemleak_alloc+0x4a/0xa0 [<ffffffffb8238a96>] kmem_cache_alloc_node+0x146/0x1f0 [<ffffffffb870e52b>] __alloc_skb+0x5b/0x1e0 [<ffffffffb814fc5c>] audit_make_reply+0x5c/0xd0 [<ffffffffb815160a>] audit_receive_msg+0xa1a/0xe60 [<ffffffffb8151aa3>] audit_receive+0x53/0xa0 [<ffffffffb875e95b>] netlink_unicast+0x18b/0x220 [<ffffffffb875ecb5>] netlink_sendmsg+0x2c5/0x3c0 [<ffffffffb8705008>] sock_sendmsg+0x38/0x50 [<ffffffffb870558f>] SYSC_sendto+0x13f/0x180 [<ffffffffb870608e>] SyS_sendto+0xe/0x10 [<ffffffffb8003a57>] do_syscall_64+0x67/0x140 [<ffffffffb8865ca7>] return_from_SYSCALL_64+0x0/0x6a [<ffffffffffffffff>] 0xffffffffffffffff unreferenced object 0xffff96595a9da600 (size 512): comm "auditd", pid 401, jiffies 4294671604 (age 62.331s) hex dump (first 32 bytes): 14 00 00 00 31 05 00 00 00 00 00 00 00 00 00 00 ....1........... 91 01 00 00 01 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffffb8859baa>] kmemleak_alloc+0x4a/0xa0 [<ffffffffb823c8a3>] __kmalloc_node_track_caller+0x233/0x2f0 [<ffffffffb870d9d1>] __kmalloc_reserve.isra.38+0x31/0x90 [<ffffffffb870e557>] __alloc_skb+0x87/0x1e0 [<ffffffffb814fc5c>] audit_make_reply+0x5c/0xd0 [<ffffffffb815160a>] audit_receive_msg+0xa1a/0xe60 [<ffffffffb8151aa3>] audit_receive+0x53/0xa0 [<ffffffffb875e95b>] netlink_unicast+0x18b/0x220 [<ffffffffb875ecb5>] netlink_sendmsg+0x2c5/0x3c0 [<ffffffffb8705008>] sock_sendmsg+0x38/0x50 [<ffffffffb870558f>] SYSC_sendto+0x13f/0x180 [<ffffffffb870608e>] SyS_sendto+0xe/0x10 [<ffffffffb8003a57>] do_syscall_64+0x67/0x140 [<ffffffffb8865ca7>] return_from_SYSCALL_64+0x0/0x6a [<ffffffffffffffff>] 0xffffffffffffffff These skb objects have been allocated in audit_replace(). If some error happened in auditd_send_unicast_skb(), skb is needed to be freed. Signed-off-by: Masami Ichikawa <masami256(a)gmail.com&gt; --- kernel/audit.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/kernel/audit.c b/kernel/audit.c index 833267bbd80b..789f4cc1f481 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -659,6 +659,7 @@ static int auditd_send_unicast_skb(struct sk_buff *skb) err: if (ac && rc == -ECONNREFUSED) auditd_reset(ac); + kfree_skb(skb); return rc; } -- 2.13.0