glibc: Security fix for CVE-2016-4429

Signed-off-by: Armin Kuster <akuster@mvista.com>

2 files changed, 90 insertions, 0 deletions

diff --git a/meta/recipes-core/glibc/glibc/CVE-2016-4429.patch b/meta/recipes-core/glibc/glibc/CVE-2016-4429.patch
new file mode 100644
index 0000000000..24aa9a41a1
--- /dev/null
+++ b/meta/recipes-core/glibc/glibc/CVE-2016-4429.patch
@@ -0,0 +1,89 @@
+From bc779a1a5b3035133024b21e2f339fe4219fb11c Mon Sep 17 00:00:00 2001
+From: Florian Weimer <fweimer@redhat.com>
+Date: Mon, 23 May 2016 20:18:34 +0200
+Subject: [PATCH] CVE-2016-4429: sunrpc: Do not use alloca in clntudp_call [BZ
+ #20112]
+
+The call is technically in a loop, and under certain circumstances
+(which are quite difficult to reproduce in a test case), alloca
+can be invoked repeatedly during a single call to clntudp_call.
+As a result, the available stack space can be exhausted (even
+though individual alloca sizes are bounded implicitly by what
+can fit into a UDP packet, as a side effect of the earlier
+successful send operation).
+
+Upstream-Status: Backport
+CVE: CVE-2016-4429
+Signed-off-by: Armin Kuster <akuster@mvista.com>
+
+---
+ ChangeLog         |  7 +++++++
+ NEWS              |  4 ++++
+ sunrpc/clnt_udp.c | 10 +++++++++-
+ 3 files changed, 20 insertions(+), 1 deletion(-)
+
+Index: git/ChangeLog
+===================================================================
+--- git.orig/ChangeLog
++++ git/ChangeLog
+@@ -1,3 +1,10 @@
++2016-05-23  Florian Weimer  <fweimer@redhat.com>
++
++   CVE-2016-4429
++   [BZ #20112]
++   * sunrpc/clnt_udp.c (clntudp_call): Use malloc/free for the error
++   payload.
++
+ 2016-04-29  Florian Weimer  <fweimer@redhat.com>
+ 
+     [BZ #20010]
+Index: git/NEWS
+===================================================================
+--- git.orig/NEWS
++++ git/NEWS
+@@ -5,6 +5,11 @@ See the end for copying conditions.
+ Security related changes:
+ 
+ [Add security related changes here]
++
++* The Sun RPC UDP client could exhaust all available stack space when
++  flooded with crafted ICMP and UDP messages.  Reported by Aldy Hernandez'
++  alloca plugin for GCC.  (CVE-2016-4429)
++
+  * Previously, getaddrinfo copied large amounts of address data to the stack,
+   even after the fix for CVE-2013-4458 has been applied, potentially
+   resulting in a stack overflow.  getaddrinfo now uses a heap allocation
+Index: git/sunrpc/clnt_udp.c
+===================================================================
+--- git.orig/sunrpc/clnt_udp.c
++++ git/sunrpc/clnt_udp.c
+@@ -420,9 +420,15 @@ send_again:
+ 	  struct sock_extended_err *e;
+ 	  struct sockaddr_in err_addr;
+ 	  struct iovec iov;
+-	  char *cbuf = (char *) alloca (outlen + 256);
++	  char *cbuf = malloc (outlen + 256);
+ 	  int ret;
+ 
++	  if (cbuf == NULL)
++	    {
++	      cu->cu_error.re_errno = errno;
++	      return (cu->cu_error.re_status = RPC_CANTRECV);
++	    }
++
+ 	  iov.iov_base = cbuf + 256;
+ 	  iov.iov_len = outlen;
+ 	  msg.msg_name = (void *) &err_addr;
+@@ -447,10 +453,12 @@ send_again:
+ 		 cmsg = CMSG_NXTHDR (&msg, cmsg))
+ 	      if (cmsg->cmsg_level == SOL_IP && cmsg->cmsg_type == IP_RECVERR)
+ 		{
++		  free (cbuf);
+ 		  e = (struct sock_extended_err *) CMSG_DATA(cmsg);
+ 		  cu->cu_error.re_errno = e->ee_errno;
+ 		  return (cu->cu_error.re_status = RPC_CANTRECV);
+ 		}
++	  free (cbuf);
+ 	}
+ #endif
+       do
diff --git a/meta/recipes-core/glibc/glibc_2.22.bb b/meta/recipes-core/glibc/glibc_2.22.bb
index 4cf2ed7dbf..a423d3dbb7 100644
--- a/meta/recipes-core/glibc/glibc_2.22.bb
+++ b/meta/recipes-core/glibc/glibc_2.22.bb
@@ -49,6 +49,7 @@ SRC_URI = "${GLIBC_GIT_URI};branch=${SRCBRANCH};name=glibc \
            file://CVE-2015-7547.patch \
            file://CVE-2015-8778.patch \
            file://CVE-2016-3706.patch \
+           file://CVE-2016-4429.patch \
 "
 
 SRC_URI += "\