diff mbox series

[RESEND,bpf,v3,3/8] udp: fix a memory leak in udp_read_sock()

Message ID 20210615021342.7416-4-xiyou.wangcong@gmail.com (mailing list archive)
State Accepted
Commit e00a5c331bf57f41fcfdc5da4f5caeafe5e54c1d
Delegated to: BPF
Headers show
Series sock_map: some bug fixes and improvements | expand

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netdev/cc_maintainers fail 1 blamed authors not CCed: ast@kernel.org; 10 maintainers not CCed: dsahern@kernel.org yhs@fb.com kpsingh@kernel.org yoshfuji@linux-ipv6.org andrii@kernel.org kafai@fb.com ast@kernel.org songliubraving@fb.com davem@davemloft.net kuba@kernel.org
netdev/source_inline success Was 0 now: 0
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netdev/build_32bit success Errors and warnings before: 7 this patch: 7
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netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 13 lines checked
netdev/build_allmodconfig_warn success Errors and warnings before: 7 this patch: 7
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Commit Message

Cong Wang June 15, 2021, 2:13 a.m. UTC 
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 mbox series

Patch

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;
 	}