diff options
author | Eric Dumazet <edumazet@google.com> | 2015-04-16 18:10:35 -0700 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-04-17 13:28:31 -0400 |
commit | 521f1cf1dbb9d5ad858dca5dc75d1b45f64b6589 (patch) | |
tree | 2c6276958f5d7348616d887f4a64f5b78ec6b9ef /net/ipv4/tcp_westwood.c | |
parent | fad9dfefea6405039491e7e4fc21fb6e59e7d26c (diff) | |
download | linux-521f1cf1dbb9d5ad858dca5dc75d1b45f64b6589.tar.bz2 |
inet_diag: fix access to tcp cc information
Two different problems are fixed here :
1) inet_sk_diag_fill() might be called without socket lock held.
icsk->icsk_ca_ops can change under us and module be unloaded.
-> Access to freed memory.
Fix this using rcu_read_lock() to prevent module unload.
2) Some TCP Congestion Control modules provide information
but again this is not safe against icsk->icsk_ca_ops
change and nla_put() errors were ignored. Some sockets
could not get the additional info if skb was almost full.
Fix this by returning a status from get_info() handlers and
using rcu protection as well.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_westwood.c')
-rw-r--r-- | net/ipv4/tcp_westwood.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/net/ipv4/tcp_westwood.c b/net/ipv4/tcp_westwood.c index bb63fba47d47..b3c57cceb990 100644 --- a/net/ipv4/tcp_westwood.c +++ b/net/ipv4/tcp_westwood.c @@ -256,8 +256,7 @@ static void tcp_westwood_event(struct sock *sk, enum tcp_ca_event event) } /* Extract info for Tcp socket info provided via netlink. */ -static void tcp_westwood_info(struct sock *sk, u32 ext, - struct sk_buff *skb) +static int tcp_westwood_info(struct sock *sk, u32 ext, struct sk_buff *skb) { const struct westwood *ca = inet_csk_ca(sk); @@ -268,8 +267,9 @@ static void tcp_westwood_info(struct sock *sk, u32 ext, .tcpv_minrtt = jiffies_to_usecs(ca->rtt_min), }; - nla_put(skb, INET_DIAG_VEGASINFO, sizeof(info), &info); + return nla_put(skb, INET_DIAG_VEGASINFO, sizeof(info), &info); } + return 0; } static struct tcp_congestion_ops tcp_westwood __read_mostly = { |