commit:     e0692eb07e906a70bcde1e57a59f2f835862fe24
Author:     Mike Pagano <mpagano <AT> gentoo <DOT> org>
AuthorDate: Fri Feb 24 00:38:12 2017 +0000
Commit:     Mike Pagano <mpagano <AT> gentoo <DOT> org>
CommitDate: Fri Feb 24 00:38:12 2017 +0000
URL:        https://gitweb.gentoo.org/proj/linux-patches.git/commit/?id=e0692eb0

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

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

diff --git a/0000_README b/0000_README
index b0d6eb6..0bee2eb 100644
--- a/0000_README
+++ b/0000_README
@@ -255,6 +255,10 @@ 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:  1900_xfs-fix-suspend-to-memory.patch
 From:   
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/patch/fs/xfs/xfs_trans_ail.c?id=18f1df4e00cea2eae41f3e5515b94d1e7127b2b6
 Desc:   xfs: Make xfsaild freezeable again. See bug #575034.

diff --git a/1520_CVE-2017-6074-dccp-skb-freeing-fix.patch 
b/1520_CVE-2017-6074-dccp-skb-freeing-fix.patch
new file mode 100644
index 0000000..433fd4b
--- /dev/null
+++ b/1520_CVE-2017-6074-dccp-skb-freeing-fix.patch
@@ -0,0 +1,47 @@
+From 5edabca9d4cff7f1f2b68f0bac55ef99d9798ba4 Mon Sep 17 00:00:00 2001
+From: Andrey Konovalov <[email protected]>
+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 <[email protected]>
+Acked-by: Eric Dumazet <[email protected]>
+Signed-off-by: David S. Miller <[email protected]>
+---
+ 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
+

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