[52/91] tcp: cookie transactions setsockopt memory leak

From: Greg KH
Date: Tue Aug 24 2010 - 18:59:18 EST


2.6.34-stable review patch. If anyone has any objections, please let us know.

------------------


From: Dmitry Popov <dp@xxxxxxxxxxxxxxx>

[ Upstream commit a3bdb549e30e7a263f7a589747c40e9c50110315 ]

There is a bug in do_tcp_setsockopt(net/ipv4/tcp.c),
TCP_COOKIE_TRANSACTIONS case.
In some cases (when tp->cookie_values == NULL) new tcp_cookie_values
structure can be allocated (at cvp), but not bound to
tp->cookie_values. So a memory leak occurs.

Signed-off-by: Dmitry Popov <dp@xxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---
net/ipv4/tcp.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2175,6 +2175,8 @@ static int do_tcp_setsockopt(struct sock
GFP_KERNEL);
if (cvp == NULL)
return -ENOMEM;
+
+ kref_init(&cvp->kref);
}
lock_sock(sk);
tp->rx_opt.cookie_in_always =
@@ -2189,12 +2191,11 @@ static int do_tcp_setsockopt(struct sock
*/
kref_put(&tp->cookie_values->kref,
tcp_cookie_values_release);
- kref_init(&cvp->kref);
- tp->cookie_values = cvp;
} else {
cvp = tp->cookie_values;
}
}
+
if (cvp != NULL) {
cvp->cookie_desired = ctd.tcpct_cookie_desired;

@@ -2208,6 +2209,8 @@ static int do_tcp_setsockopt(struct sock
cvp->s_data_desired = ctd.tcpct_s_data_desired;
cvp->s_data_constant = 0; /* false */
}
+
+ tp->cookie_values = cvp;
}
release_sock(sk);
return err;


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