Backport fix for issues with Quagga introduced by CVE fixes (rhbz 1097684)

This commit is contained in:
Josh Boyer 2014-06-03 08:45:41 -04:00
parent bda74fc058
commit ca9a2b84bf
2 changed files with 120 additions and 0 deletions

View File

@ -753,6 +753,8 @@ Patch25083: 2-5-net-Move-the-permission-check-in-sock_diag_put_filterinfo-to-pac
Patch25084: 3-5-net-Add-variants-of-capable-for-use-on-on-sockets.patch
Patch25085: 4-5-net-Add-variants-of-capable-for-use-on-netlink-messages.patch
Patch25086: 5-5-net-Use-netlink_ns_capable-to-verify-the-permisions-of-netlink-messages.patch
#rhbz 1094265 1097684
Patch25094: netlink-Only-check-file-credentials-for-implicit-des.patch
#rhbz 1082266
Patch25087: jme-fix-dma-unmap-error.patch
@ -1471,6 +1473,8 @@ ApplyPatch 2-5-net-Move-the-permission-check-in-sock_diag_put_filterinfo-to-pack
ApplyPatch 3-5-net-Add-variants-of-capable-for-use-on-on-sockets.patch
ApplyPatch 4-5-net-Add-variants-of-capable-for-use-on-netlink-messages.patch
ApplyPatch 5-5-net-Use-netlink_ns_capable-to-verify-the-permisions-of-netlink-messages.patch
#rhbz 1094265 1097684
ApplyPatch netlink-Only-check-file-credentials-for-implicit-des.patch
#rhbz 1082266
ApplyPatch jme-fix-dma-unmap-error.patch
@ -2295,6 +2299,9 @@ fi
# ||----w |
# || ||
%changelog
* Tue Jun 03 2014 Josh Boyer <jwboyer@fedoraproject.org>
- Backport fix for issues with Quagga introduced by CVE fixes (rhbz 1097684)
* Mon Jun 02 2014 Justin M. Forbes <jforbes@fedoraproject.org> - 3.14.5-200
- Linux v3.14.5

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@ -0,0 +1,113 @@
Bugzilla: 1097684 1094265
Upstream-status: 3.15
From 2d7a85f4b06e9c27ff629f07a524c48074f07f81 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@xmission.com>
Date: Fri, 30 May 2014 11:04:00 -0700
Subject: [PATCH] netlink: Only check file credentials for implicit
destinations
It was possible to get a setuid root or setcap executable to write to
it's stdout or stderr (which has been set made a netlink socket) and
inadvertently reconfigure the networking stack.
To prevent this we check that both the creator of the socket and
the currentl applications has permission to reconfigure the network
stack.
Unfortunately this breaks Zebra which always uses sendto/sendmsg
and creates it's socket without any privileges.
To keep Zebra working don't bother checking if the creator of the
socket has privilege when a destination address is specified. Instead
rely exclusively on the privileges of the sender of the socket.
Note from Andy: This is exactly Eric's code except for some comment
clarifications and formatting fixes. Neither I nor, I think, anyone
else is thrilled with this approach, but I'm hesitant to wait on a
better fix since 3.15 is almost here.
Note to stable maintainers: This is a mess. An earlier series of
patches in 3.15 fix a rather serious security issue (CVE-2014-0181),
but they did so in a way that breaks Zebra. The offending series
includes:
commit aa4cf9452f469f16cea8c96283b641b4576d4a7b
Author: Eric W. Biederman <ebiederm@xmission.com>
Date: Wed Apr 23 14:28:03 2014 -0700
net: Add variants of capable for use on netlink messages
If a given kernel version is missing that series of fixes, it's
probably worth backporting it and this patch. if that series is
present, then this fix is critical if you care about Zebra.
Cc: stable@vger.kernel.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/netlink.h | 7 ++++---
net/netlink/af_netlink.c | 7 ++++++-
2 files changed, 10 insertions(+), 4 deletions(-)
diff --git a/include/linux/netlink.h b/include/linux/netlink.h
index f64b017..034cda7 100644
--- a/include/linux/netlink.h
+++ b/include/linux/netlink.h
@@ -16,9 +16,10 @@ static inline struct nlmsghdr *nlmsg_hdr(const struct sk_buff *skb)
}
enum netlink_skb_flags {
- NETLINK_SKB_MMAPED = 0x1, /* Packet data is mmaped */
- NETLINK_SKB_TX = 0x2, /* Packet was sent by userspace */
- NETLINK_SKB_DELIVERED = 0x4, /* Packet was delivered */
+ NETLINK_SKB_MMAPED = 0x1, /* Packet data is mmaped */
+ NETLINK_SKB_TX = 0x2, /* Packet was sent by userspace */
+ NETLINK_SKB_DELIVERED = 0x4, /* Packet was delivered */
+ NETLINK_SKB_DST = 0x8, /* Dst set in sendto or sendmsg */
};
struct netlink_skb_parms {
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 81dca96..f22757a 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1373,7 +1373,9 @@ retry:
bool __netlink_ns_capable(const struct netlink_skb_parms *nsp,
struct user_namespace *user_ns, int cap)
{
- return sk_ns_capable(nsp->sk, user_ns, cap);
+ return ((nsp->flags & NETLINK_SKB_DST) ||
+ file_ns_capable(nsp->sk->sk_socket->file, user_ns, cap)) &&
+ ns_capable(user_ns, cap);
}
EXPORT_SYMBOL(__netlink_ns_capable);
@@ -2293,6 +2295,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
struct sk_buff *skb;
int err;
struct scm_cookie scm;
+ u32 netlink_skb_flags = 0;
if (msg->msg_flags&MSG_OOB)
return -EOPNOTSUPP;
@@ -2314,6 +2317,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
if ((dst_group || dst_portid) &&
!netlink_allowed(sock, NL_CFG_F_NONROOT_SEND))
goto out;
+ netlink_skb_flags |= NETLINK_SKB_DST;
} else {
dst_portid = nlk->dst_portid;
dst_group = nlk->dst_group;
@@ -2343,6 +2347,7 @@ static int netlink_sendmsg(struct kiocb *kiocb, struct socket *sock,
NETLINK_CB(skb).portid = nlk->portid;
NETLINK_CB(skb).dst_group = dst_group;
NETLINK_CB(skb).creds = siocb->scm->creds;
+ NETLINK_CB(skb).flags = netlink_skb_flags;
err = -EFAULT;
if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
--
1.9.3