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, 23 Feb 2012 15:36:26 +0100
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Niccolò Belli <darkbasic@...uxsystems.it>,
	David Miller <davem@...emloft.net>
Cc:	Linux Networking Developer Mailing List <netdev@...r.kernel.org>,
	openadsl-users@...ts.sourceforge.net,
	openadsl-devel@...ts.sourceforge.net, 660804@...s.debian.org,
	support@...verse.com.au, support@...ksolidelectronics.com
Subject: Re: [Bug 42809] New: kernel panic when receiving an ipsec packet


> Your patch does solve the problem, thanks!
> 

Thanks for testing.

Here is the official patch I submit for review then.

[PATCH] ipsec: be careful of non existing mac headers

Nicollo Belli reported ipsec crashes in case we handle a frame without
mac header (atm in his case)

Before copying mac header, better make sure it is present.

Bugzilla reference:  https://bugzilla.kernel.org/show_bug.cgi?id=42809

Reported-by: Niccolò Belli <darkbasic@...uxsystems.it>
Tested-by: Niccolò Belli <darkbasic@...uxsystems.it>
Signed-off-by: Eric Dumazet <eric.dumazet@...il.com>
---
 net/ipv4/xfrm4_mode_beet.c   |    9 +++++----
 net/ipv4/xfrm4_mode_tunnel.c |   10 ++++++----
 net/ipv6/xfrm6_mode_beet.c   |    9 +++++----
 net/ipv6/xfrm6_mode_tunnel.c |   10 ++++++----
 4 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/net/ipv4/xfrm4_mode_beet.c b/net/ipv4/xfrm4_mode_beet.c
index 6341818..d3451f6 100644
--- a/net/ipv4/xfrm4_mode_beet.c
+++ b/net/ipv4/xfrm4_mode_beet.c
@@ -111,10 +111,11 @@ static int xfrm4_beet_input(struct xfrm_state *x, struct sk_buff *skb)
 	skb_push(skb, sizeof(*iph));
 	skb_reset_network_header(skb);
 
-	memmove(skb->data - skb->mac_len, skb_mac_header(skb),
-		skb->mac_len);
-	skb_set_mac_header(skb, -skb->mac_len);
-
+	if (skb_mac_header_was_set(skb)) {
+		memmove(skb->data - skb->mac_len, skb_mac_header(skb),
+			skb->mac_len);
+		skb_set_mac_header(skb, -skb->mac_len);
+	}
 	xfrm4_beet_make_header(skb);
 
 	iph = ip_hdr(skb);
diff --git a/net/ipv4/xfrm4_mode_tunnel.c b/net/ipv4/xfrm4_mode_tunnel.c
index 534972e..a646f30 100644
--- a/net/ipv4/xfrm4_mode_tunnel.c
+++ b/net/ipv4/xfrm4_mode_tunnel.c
@@ -66,7 +66,6 @@ static int xfrm4_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 
 static int xfrm4_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 {
-	const unsigned char *old_mac;
 	int err = -EINVAL;
 
 	if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
@@ -84,9 +83,12 @@ static int xfrm4_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 	if (!(x->props.flags & XFRM_STATE_NOECN))
 		ipip_ecn_decapsulate(skb);
 
-	old_mac = skb_mac_header(skb);
-	skb_set_mac_header(skb, -skb->mac_len);
-	memmove(skb_mac_header(skb), old_mac, skb->mac_len);
+	if (skb_mac_header_was_set(skb)) {
+		const unsigned char *old_mac = skb_mac_header(skb);
+
+		skb_set_mac_header(skb, -skb->mac_len);
+		memmove(skb_mac_header(skb), old_mac, skb->mac_len);
+	}
 	skb_reset_network_header(skb);
 	err = 0;
 
diff --git a/net/ipv6/xfrm6_mode_beet.c b/net/ipv6/xfrm6_mode_beet.c
index a81ce94..74c4b92 100644
--- a/net/ipv6/xfrm6_mode_beet.c
+++ b/net/ipv6/xfrm6_mode_beet.c
@@ -80,7 +80,6 @@ static int xfrm6_beet_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm6_beet_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	struct ipv6hdr *ip6h;
-	const unsigned char *old_mac;
 	int size = sizeof(struct ipv6hdr);
 	int err;
 
@@ -91,10 +90,12 @@ static int xfrm6_beet_input(struct xfrm_state *x, struct sk_buff *skb)
 	__skb_push(skb, size);
 	skb_reset_network_header(skb);
 
-	old_mac = skb_mac_header(skb);
-	skb_set_mac_header(skb, -skb->mac_len);
-	memmove(skb_mac_header(skb), old_mac, skb->mac_len);
+	if (skb_mac_header_was_set(skb)) {
+		const unsigned char *old_mac = skb_mac_header(skb);
 
+		skb_set_mac_header(skb, -skb->mac_len);
+		memmove(skb_mac_header(skb), old_mac, skb->mac_len);
+	}
 	xfrm6_beet_make_header(skb);
 
 	ip6h = ipv6_hdr(skb);
diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c
index 261e6e6..edb7091 100644
--- a/net/ipv6/xfrm6_mode_tunnel.c
+++ b/net/ipv6/xfrm6_mode_tunnel.c
@@ -63,7 +63,6 @@ static int xfrm6_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
 static int xfrm6_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 {
 	int err = -EINVAL;
-	const unsigned char *old_mac;
 
 	if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPV6)
 		goto out;
@@ -80,9 +79,12 @@ static int xfrm6_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
 	if (!(x->props.flags & XFRM_STATE_NOECN))
 		ipip6_ecn_decapsulate(skb);
 
-	old_mac = skb_mac_header(skb);
-	skb_set_mac_header(skb, -skb->mac_len);
-	memmove(skb_mac_header(skb), old_mac, skb->mac_len);
+	if (skb_mac_header_was_set(skb)) {
+		const unsigned char *old_mac = skb_mac_header(skb);
+
+		skb_set_mac_header(skb, -skb->mac_len);
+		memmove(skb_mac_header(skb), old_mac, skb->mac_len);
+	}
 	skb_reset_network_header(skb);
 	err = 0;
 


--
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

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ