[gentoo-commits] proj/linux-patches:4.1 commit in: /

[Mike Pagano]

commit:     6ed8b62e018b2d75b73c9d848d64b1394c1e362a
Author:     Mike Pagano <mpagano <AT> gentoo <DOT> org>
AuthorDate: Fri Feb 24 16:11:39 2017 +0000
Commit:     Mike Pagano <mpagano <AT> gentoo <DOT> org>
CommitDate: Fri Feb 24 16:11:39 2017 +0000
URL:        https://gitweb.gentoo.org/proj/linux-patches.git/commit/?id=6ed8b62e

dccp: fix freeing skb too early for IPV6_RECVPKTINFO. CVE-2017-6074

 0000_README                                      |  4 ++
 1520_CVE-2017-6074-dccp-fix-early-skb-free.patch | 47 ++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/0000_README b/0000_README
index 061bd5e..9c6c940 100644
--- a/0000_README
+++ b/0000_README
@@ -203,6 +203,10 @@ Patch:  1510_fs-enable-link-security-restrictions-by-default.patch
 From:   http://sources.debian.net/src/linux/3.16.7-ckt4-3/debian/patches/debian/fs-enable-link-security-restrictions-by-default.patch/
 Desc:   Enable link security restrictions by default.
 
+Patch:  1520_CVE-2017-6074-dccp-skb-freeing-fix.patch
+From:   https://bugs.gentoo.org/show_bug.cgi?id=610600
+Desc:   dccp: fix freeing skb too early for IPV6_RECVPKTINFO. CVE-2017-6074
+
 Patch:  1800_fix-lru-cache-add-oom-regression.patch
 From:   http://thread.gmane.org/gmane.linux.kernel.stable/184384
 Desc:   Revert commit 8f182270dfec mm/swap.c: flush lru pvecs on compound page arrival to fix OOM error.

diff --git a/1520_CVE-2017-6074-dccp-fix-early-skb-free.patch b/1520_CVE-2017-6074-dccp-fix-early-skb-free.patch
new file mode 100644
index 0000000..433fd4b
--- /dev/null
+++ b/1520_CVE-2017-6074-dccp-fix-early-skb-free.patch
@@ -0,0 +1,47 @@
+From 5edabca9d4cff7f1f2b68f0bac55ef99d9798ba4 Mon Sep 17 00:00:00 2001
+From: Andrey Konovalov <andreyknvl@××××××.com>
+Date: Thu, 16 Feb 2017 17:22:46 +0100
+Subject: dccp: fix freeing skb too early for IPV6_RECVPKTINFO
+
+In the current DCCP implementation an skb for a DCCP_PKT_REQUEST packet
+is forcibly freed via __kfree_skb in dccp_rcv_state_process if
+dccp_v6_conn_request successfully returns.
+
+However, if IPV6_RECVPKTINFO is set on a socket, the address of the skb
+is saved to ireq->pktopts and the ref count for skb is incremented in
+dccp_v6_conn_request, so skb is still in use. Nevertheless, it gets freed
+in dccp_rcv_state_process.
+
+Fix by calling consume_skb instead of doing goto discard and therefore
+calling __kfree_skb.
+
+Similar fixes for TCP:
+
+fb7e2399ec17f1004c0e0ccfd17439f8759ede01 [TCP]: skb is unexpectedly freed.
+0aea76d35c9651d55bbaf746e7914e5f9ae5a25d tcp: SYN packets are now
+simply consumed
+
+Signed-off-by: Andrey Konovalov <andreyknvl@××××××.com>
+Acked-by: Eric Dumazet <edumazet@××××××.com>
+Signed-off-by: David S. Miller <davem@×××××××××.net>
+---
+ net/dccp/input.c | 3 ++-
+ 1 file changed, 2 insertions(+), 1 deletion(-)
+
+diff --git a/net/dccp/input.c b/net/dccp/input.c
+index ba34718..8fedc2d 100644
+--- a/net/dccp/input.c
++++ b/net/dccp/input.c
+@@ -606,7 +606,8 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
+ 			if (inet_csk(sk)->icsk_af_ops->conn_request(sk,
+ 								    skb) < 0)
+ 				return 1;
+-			goto discard;
++			consume_skb(skb);
++			return 0;
+ 		}
+ 		if (dh->dccph_type == DCCP_PKT_RESET)
+ 			goto discard;
+-- 
+cgit v0.12
+