[PATCH] ISDN, Gigaset: Fix memory leak in do_disconnect_req()

From: Jesper Juhl
Date: Sun Dec 26 2010 - 15:09:54 EST


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@xxxxxxxxxxxxx>
---
capi.c | 1 +
1 file changed, 1 insertion(+)

compile tested only since I have no way to actually test this.

diff --git a/drivers/isdn/gigaset/capi.c b/drivers/isdn/gigaset/capi.c
index bcc174e..658e75f 100644
--- a/drivers/isdn/gigaset/capi.c
+++ b/drivers/isdn/gigaset/capi.c
@@ -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,


--
Jesper Juhl <jj@xxxxxxxxxxxxx> http://www.chaosbits.net/
Don't top-post http://www.catb.org/~esr/jargon/html/T/top-post.html
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