netdev - [PATCH] xfrm: check bundle policy existance before dereferencing it

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 24 Jun 2010 08:45:19 +0300
From:	Timo Teräs <timo.teras@....fi>
To:	netdev@...r.kernel.org,
	"Justin P. Mattock" <justinmattock@...il.com>,
	Eric Dumazet <eric.dumazet@...il.com>,
	"John W.Linville" <linville@...driver.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	davem@...emloft.net
Cc:	Timo Teräs <timo.teras@....fi>
Subject: [PATCH] xfrm: check bundle policy existance before dereferencing it

Fix the bundle validation code to not assume having a valid policy.
When we have multiple transformations for a xfrm policy, the bundle
instance will be a chain of bundles with only the first one having
the policy reference. When policy_genid is bumped it will expire the
first bundle in the chain which is equivalent of expiring the whole
chain.

Reported-bisected-and-tested-by: Justin P. Mattock <justinmattock@...il.com>
Signed-off-by: Timo Teräs <timo.teras@....fi>
---
 net/xfrm/xfrm_policy.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 4bf27d9..af1c173 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2300,7 +2300,8 @@ int xfrm_bundle_ok(struct xfrm_policy *pol, struct xfrm_dst *first,
 			return 0;
 		if (xdst->xfrm_genid != dst->xfrm->genid)
 			return 0;
-		if (xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
+		if (xdst->num_pols > 0 &&
+		    xdst->policy_genid != atomic_read(&xdst->pols[0]->genid))
 			return 0;
 
 		if (strict && fl &&
-- 
1.7.0.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html