diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-09-25 07:39:22 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-09-25 13:00:39 -0700 |
| commit | 802885fc0400d0166a6b65d1844b61696aecbb10 (patch) | |
| tree | 7f6e6d083adf632704d496642eab95ad3c969e93 /net/dccp/output.c | |
| parent | 0f935dbedc49a5044ebff08b47eef35a2f2bbe92 (diff) | |
| download | lwn-802885fc0400d0166a6b65d1844b61696aecbb10.tar.gz lwn-802885fc0400d0166a6b65d1844b61696aecbb10.zip | |
dccp: constify dccp_make_response() socket argument
Like tcp_make_synack() the only time we might change the socket is
when calling sock_wmalloc(), which is using atomic operation to
update sk->sk_wmem_alloc
Also use MAX_DCCP_HEADER as both IPv4/IPv6 use this value for max_header.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/dccp/output.c')
| -rw-r--r-- | net/dccp/output.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/net/dccp/output.c b/net/dccp/output.c index 0248e8a3460c..4ce912e691d0 100644 --- a/net/dccp/output.c +++ b/net/dccp/output.c @@ -390,7 +390,7 @@ int dccp_retransmit_skb(struct sock *sk) return dccp_transmit_skb(sk, skb_clone(sk->sk_send_head, GFP_ATOMIC)); } -struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, +struct sk_buff *dccp_make_response(const struct sock *sk, struct dst_entry *dst, struct request_sock *req) { struct dccp_hdr *dh; @@ -398,13 +398,18 @@ struct sk_buff *dccp_make_response(struct sock *sk, struct dst_entry *dst, const u32 dccp_header_size = sizeof(struct dccp_hdr) + sizeof(struct dccp_hdr_ext) + sizeof(struct dccp_hdr_response); - struct sk_buff *skb = sock_wmalloc(sk, sk->sk_prot->max_header, 1, - GFP_ATOMIC); - if (skb == NULL) + struct sk_buff *skb; + + /* sk is marked const to clearly express we dont hold socket lock. + * sock_wmalloc() will atomically change sk->sk_wmem_alloc, + * it is safe to promote sk to non const. + */ + skb = sock_wmalloc((struct sock *)sk, MAX_DCCP_HEADER, 1, + GFP_ATOMIC); + if (!skb) return NULL; - /* Reserve space for headers. */ - skb_reserve(skb, sk->sk_prot->max_header); + skb_reserve(skb, MAX_DCCP_HEADER); skb_dst_set(skb, dst_clone(dst)); |