diff options
| author | Eric Dumazet <edumazet@google.com> | 2012-12-01 13:07:02 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-12-01 20:39:16 -0500 |
| commit | 64022d0b4e93ea432e95db55a72b8a1c5775f3c0 (patch) | |
| tree | ea2ac7d7a7ed903d645c21d99f02ff6fdbb6aa96 /net/ipv4/tcp.c | |
| parent | 9f8933e960f98d27742727445061b0ece934e5cf (diff) | |
| download | lwn-64022d0b4e93ea432e95db55a72b8a1c5775f3c0.tar.gz lwn-64022d0b4e93ea432e95db55a72b8a1c5775f3c0.zip | |
tcp: fix crashes in do_tcp_sendpages()
Recent network changes allowed high order pages being used
for skb fragments.
This uncovered a bug in do_tcp_sendpages() which was assuming its caller
provided an array of order-0 page pointers.
We only have to deal with a single page in this function, and its order
is irrelevant.
Reported-by: Willy Tarreau <w@1wt.eu>
Tested-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp.c')
| -rw-r--r-- | net/ipv4/tcp.c | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 083092e3aed6..e457c7ab2e28 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -830,8 +830,8 @@ static int tcp_send_mss(struct sock *sk, int *size_goal, int flags) return mss_now; } -static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffset, - size_t psize, int flags) +static ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, + size_t size, int flags) { struct tcp_sock *tp = tcp_sk(sk); int mss_now, size_goal; @@ -858,12 +858,9 @@ static ssize_t do_tcp_sendpages(struct sock *sk, struct page **pages, int poffse if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN)) goto out_err; - while (psize > 0) { + while (size > 0) { struct sk_buff *skb = tcp_write_queue_tail(sk); - struct page *page = pages[poffset / PAGE_SIZE]; int copy, i; - int offset = poffset % PAGE_SIZE; - int size = min_t(size_t, psize, PAGE_SIZE - offset); bool can_coalesce; if (!tcp_send_head(sk) || (copy = size_goal - skb->len) <= 0) { @@ -912,8 +909,8 @@ new_segment: TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH; copied += copy; - poffset += copy; - if (!(psize -= copy)) + offset += copy; + if (!(size -= copy)) goto out; if (skb->len < size_goal || (flags & MSG_OOB)) @@ -960,7 +957,7 @@ int tcp_sendpage(struct sock *sk, struct page *page, int offset, flags); lock_sock(sk); - res = do_tcp_sendpages(sk, &page, offset, size, flags); + res = do_tcp_sendpages(sk, page, offset, size, flags); release_sock(sk); return res; } |