Re: Bug somewhere in crypto or ipsec stuff

["YOSHIFUJI Hideaki / 吉藤英明" <yoshfuji@linux-ipv6.org>]

In article <Xine.LNX.4.44.0310292344530.23580-100000@thoron.boston.redhat.com> (at Wed, 29 Oct 2003 23:47:05 -0500 (EST)), James Morris <jmorris@redhat.com> says:

> > Do you mean that we need to fix the caller?
> 
> Yes.

> >  - crypto allows name == NULL, and return any algorithm
> >    (for example, an algorithm that we see first.)
> >  - caller may filter name == NULL case if it is ambiguous in their context.
> 
> I think that could be dangerous, including if calling with null is a 
> bug, and they get an inappropriate algorithm.  An incorrect algorithm type 
> could also be returned (e.g. digest instead of a cipher).

okay. how about this?

===== crypto/api.c 1.30 vs edited =====
--- 1.30/crypto/api.c	Sat Mar 29 20:16:58 2003
+++ edited/crypto/api.c	Thu Oct 30 14:21:53 2003
@@ -36,6 +36,9 @@
 struct crypto_alg *crypto_alg_lookup(const char *name)
 {
 	struct crypto_alg *q, *alg = NULL;
+
+	if (!name)
+		return NULL;
 	
 	down_read(&crypto_alg_sem);
 	
===== net/ipv4/ipcomp.c 1.16 vs edited =====
--- 1.16/net/ipv4/ipcomp.c	Mon Aug 18 20:14:38 2003
+++ edited/net/ipv4/ipcomp.c	Thu Oct 30 14:18:49 2003
@@ -360,7 +360,12 @@
 	ipcd->scratch = kmalloc(IPCOMP_SCRATCH_SIZE, GFP_KERNEL);
 	if (!ipcd->scratch)
 		goto error;
-	
+
+	if (!x->calg->alg_name) {
+		err = -EINVAL;
+		goto error;
+	}
+
 	ipcd->tfm = crypto_alloc_tfm(x->calg->alg_name, 0);
 	if (!ipcd->tfm)
 		goto error;
===== net/ipv6/ipcomp6.c 1.7 vs edited =====
--- 1.7/net/ipv6/ipcomp6.c	Mon Aug 18 20:14:38 2003
+++ edited/net/ipv6/ipcomp6.c	Thu Oct 30 14:18:49 2003
@@ -293,6 +293,11 @@
 	if (!ipcd->scratch)
 		goto error;
 
+	if (!x->calg->alg_name) {
+		err = -EINVAL;
+		goto error;
+	}
+
 	ipcd->tfm = crypto_alloc_tfm(x->calg->alg_name, 0);
 	if (!ipcd->tfm)
 		goto error;