ISDN, Gigaset: Fix memory leak in do_disconnect_req()
Jesper Juhl [Sun, 26 Dec 2010 09:59:58 +0000 (09:59 +0000)]
Hi,

In drivers/isdn/gigaset/capi.c::do_disconnect_req() we will leak the
memory allocated (with kmalloc) to 'b3cmsg' if the call to alloc_skb()
fails.

...
b3cmsg = kmalloc(sizeof(*b3cmsg), GFP_KERNEL);
allocation here ------^
if (!b3cmsg) {
dev_err(cs->dev, "%s: out of memory\n", __func__);
send_conf(iif, ap, skb, CAPI_MSGOSRESOURCEERR);
return;
}
capi_cmsg_header(b3cmsg, ap->id, CAPI_DISCONNECT_B3, CAPI_IND,
 ap->nextMessageNumber++,
 cmsg->adr.adrPLCI | (1 << 16));
b3cmsg->Reason_B3 = CapiProtocolErrorLayer1;
b3skb = alloc_skb(CAPI_DISCONNECT_B3_IND_BASELEN, GFP_KERNEL);
if (b3skb == NULL) {
dev_err(cs->dev, "%s: out of memory\n", __func__);
send_conf(iif, ap, skb, CAPI_MSGOSRESOURCEERR);
return;
leak here ------^
...

This leak is easily fixed by just kfree()'ing the memory allocated to
'b3cmsg' right before we return. The following patch does that.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/isdn/gigaset/capi.c

index bcc174e..658e75f 100644 (file)
@@ -1900,6 +1900,7 @@ static void do_disconnect_req(struct gigaset_capi_ctr *iif,
                if (b3skb == NULL) {
                        dev_err(cs->dev, "%s: out of memory\n", __func__);
                        send_conf(iif, ap, skb, CAPI_MSGOSRESOURCEERR);
+                       kfree(b3cmsg);
                        return;
                }
                capi_cmsg2message(b3cmsg,