From: Cong Wang <xiyou.wangcong@gmail.com>
To: netdev@vger.kernel.org
Cc: bpf@vger.kernel.org, Cong Wang <cong.wang@bytedance.com>,
John Fastabend <john.fastabend@gmail.com>,
Daniel Borkmann <daniel@iogearbox.net>,
Jakub Sitnicki <jakub@cloudflare.com>,
Lorenz Bauer <lmb@cloudflare.com>
Subject: [PATCH RESEND bpf v3 3/8] udp: fix a memory leak in udp_read_sock()
Date: Mon, 14 Jun 2021 19:13:37 -0700 [thread overview]
Message-ID: <20210615021342.7416-4-xiyou.wangcong@gmail.com> (raw)
In-Reply-To: <20210615021342.7416-1-xiyou.wangcong@gmail.com>
From: Cong Wang <cong.wang@bytedance.com>
sk_psock_verdict_recv() clones the skb and uses the clone
afterward, so udp_read_sock() should free the skb after using
it, regardless of error or not.
This fixes a real kmemleak.
Fixes: d7f571188ecf ("udp: Implement ->read_sock() for sockmap")
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
---
net/ipv4/udp.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 15f5504adf5b..e31d67fd5183 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1798,11 +1798,13 @@ int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
if (used <= 0) {
if (!copied)
copied = used;
+ kfree_skb(skb);
break;
} else if (used <= skb->len) {
copied += used;
}
+ kfree_skb(skb);
if (!desc->count)
break;
}
--
2.25.1
next prev parent reply other threads:[~2021-06-15 2:46 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-06-15 2:13 [PATCH RESEND bpf v3 0/8] sock_map: some bug fixes and improvements Cong Wang
2021-06-15 2:13 ` [PATCH RESEND bpf v3 1/8] skmsg: improve udp_bpf_recvmsg() accuracy Cong Wang
2021-06-15 2:13 ` [PATCH RESEND bpf v3 2/8] selftests/bpf: Retry for EAGAIN in udp_redir_to_connected() Cong Wang
2021-06-15 2:13 ` Cong Wang [this message]
2021-06-15 2:13 ` [PATCH RESEND bpf v3 4/8] skmsg: clear skb redirect pointer before dropping it Cong Wang
2021-06-15 2:13 ` [PATCH RESEND bpf v3 5/8] skmsg: fix a memory leak in sk_psock_verdict_apply() Cong Wang
2021-06-15 2:13 ` [PATCH RESEND bpf v3 6/8] skmsg: teach sk_psock_verdict_apply() to return errors Cong Wang
2021-06-15 2:13 ` [PATCH RESEND bpf v3 7/8] skmsg: pass source psock to sk_psock_skb_redirect() Cong Wang
2021-06-15 2:13 ` [PATCH RESEND bpf v3 8/8] skmsg: increase sk->sk_drops when dropping packets Cong Wang
2021-06-19 9:57 ` [PATCH RESEND bpf v3 0/8] sock_map: some bug fixes and improvements Jakub Sitnicki
2021-06-21 15:00 ` patchwork-bot+netdevbpf
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