main/linux-grsec: add a xfrm fix from upstream

1 files changed, 66 insertions, 0 deletions

diff --git a/main/linux-grsec/0021-xfrm-do-not-assume-that-template-resolving-always-returns-xfrms.patch b/main/linux-grsec/0021-xfrm-do-not-assume-that-template-resolving-always-returns-xfrms.patch
new file mode 100644
index 000000000..bc660dd5c
--- /dev/null
+++ b/main/linux-grsec/0021-xfrm-do-not-assume-that-template-resolving-always-returns-xfrms.patch
@@ -0,0 +1,66 @@
+From d809ec895505e6f35fb1965f0946381ab4eaa474 Mon Sep 17 00:00:00 2001
+From: =?utf8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi>
+Date: Mon, 12 Jul 2010 21:29:42 +0000
+Subject: [PATCH] xfrm: do not assume that template resolving always returns xfrms
+MIME-Version: 1.0
+Content-Type: text/plain; charset=utf8
+Content-Transfer-Encoding: 8bit
+
+xfrm_resolve_and_create_bundle() assumed that, if policies indicated
+presence of xfrms, bundle template resolution would always return
+some xfrms. This is not true for 'use' level policies which can
+result in no xfrm's being applied if there is no suitable xfrm states.
+This fixes a crash by this incorrect assumption.
+
+Reported-by: George Spelvin <linux@horizon.com>
+Bisected-by: George Spelvin <linux@horizon.com>
+Tested-by: George Spelvin <linux@horizon.com>
+Signed-off-by: Timo Teräs <timo.teras@iki.fi>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ net/xfrm/xfrm_policy.c |   15 +++++++++++++--
+ 1 files changed, 13 insertions(+), 2 deletions(-)
+
+diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
+index af1c173..a7ec5a8 100644
+--- a/net/xfrm/xfrm_policy.c
++++ b/net/xfrm/xfrm_policy.c
+@@ -1594,8 +1594,8 @@ xfrm_resolve_and_create_bundle(struct xfrm_policy **pols, int num_pols,
+ 
+ 	/* Try to instantiate a bundle */
+ 	err = xfrm_tmpl_resolve(pols, num_pols, fl, xfrm, family);
+-	if (err < 0) {
+-		if (err != -EAGAIN)
++	if (err <= 0) {
++		if (err != 0 && err != -EAGAIN)
+ 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTPOLERROR);
+ 		return ERR_PTR(err);
+ 	}
+@@ -1678,6 +1678,13 @@ xfrm_bundle_lookup(struct net *net, struct flowi *fl, u16 family, u8 dir,
+ 			goto make_dummy_bundle;
+ 		dst_hold(&xdst->u.dst);
+ 		return oldflo;
++	} else if (new_xdst == NULL) {
++		num_xfrms = 0;
++		if (oldflo == NULL)
++			goto make_dummy_bundle;
++		xdst->num_xfrms = 0;
++		dst_hold(&xdst->u.dst);
++		return oldflo;
+ 	}
+ 
+ 	/* Kill the previous bundle */
+@@ -1760,6 +1767,10 @@ restart:
+ 				xfrm_pols_put(pols, num_pols);
+ 				err = PTR_ERR(xdst);
+ 				goto dropdst;
++			} else if (xdst == NULL) {
++				num_xfrms = 0;
++				drop_pols = num_pols;
++				goto no_transform;
+ 			}
+ 
+ 			spin_lock_bh(&xfrm_policy_sk_bundle_lock);
+-- 
+1.7.1.1
+