summaryrefslogtreecommitdiff
path: root/net/ipv4/tcp.c
diff options
context:
space:
mode:
authorEric B Munson <emunson@akamai.com>2015-05-18 18:35:58 (GMT)
committerDavid S. Miller <davem@davemloft.net>2015-05-19 20:33:34 (GMT)
commitaea0929e516a1ff4c4458203d1f3375eee9acc26 (patch)
treedd499751b35707afda3144e78261f710b34671e6 /net/ipv4/tcp.c
parentc9a70d43461d83818825ae065bb8fc887421e150 (diff)
downloadlinux-aea0929e516a1ff4c4458203d1f3375eee9acc26.tar.xz
tcp: Return error instead of partial read for saved syn headers
Currently the getsockopt() requesting the cached contents of the syn packet headers will fail silently if the caller uses a buffer that is too small to contain the requested data. Rather than fail silently and discard the headers, getsockopt() should return an error and report the required size to hold the data. Signed-off-by: Eric B Munson <emunson@akamai.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: James Morris <jmorris@namei.org> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Patrick McHardy <kaber@trash.net> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp.c')
-rw-r--r--net/ipv4/tcp.c10
1 files changed, 9 insertions, 1 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index c724195..bb9bb84 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2845,7 +2845,15 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
lock_sock(sk);
if (tp->saved_syn) {
- len = min_t(unsigned int, tp->saved_syn[0], len);
+ if (len < tp->saved_syn[0]) {
+ if (put_user(tp->saved_syn[0], optlen)) {
+ release_sock(sk);
+ return -EFAULT;
+ }
+ release_sock(sk);
+ return -EINVAL;
+ }
+ len = tp->saved_syn[0];
if (put_user(len, optlen)) {
release_sock(sk);
return -EFAULT;