ppp: Security Advisory - CVE-2015-3310

http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2015-3310

Buffer overflow in the rc_mksid function in plugins/radius/util.c in
Paul's PPP Package (ppp) 2.4.6 and earlier, when the PID for pppd is
greater than 65535, allows remote attackers to cause a denial of
service (crash) via a start accounting message to the RADIUS server.

oe-core is using ppp 2.4.7, and this CVE say ppp 2.4.7 was not
effected, but I found this buggy codes are same between 2.4.6 and
2.4.7, and 2.4.7 should have this issue.

(From OE-Core rev: 5b549c6d73e91fdbd0b618a752d618deb1449ef9)

Signed-off-by: Roy Li <rongqing.li@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-connectivity/ppp/ppp/fix-CVE-2015-3310.patch

@@ -0,0 +1,29 @@
+ppp: Buffer overflow in radius plugin
+
+From: https://bugs.debian.org/cgi-bin/bugreport.cgi?msg=5;bug=782450
+
+Upstream-Status: Backport
+
+On systems with more than 65535 processes running, pppd aborts when
+sending a "start" accounting message to the RADIUS server because of a
+buffer overflow in rc_mksid.
+
+The process id is used in rc_mksid to generate a pseudo-unique string,
+assuming that the hex representation of the pid will be at most 4
+characters (FFFF). __sprintf_chk(), used when compiling with
+optimization levels greater than 0 and FORTIFY_SOURCE, detects the
+buffer overflow and makes pppd crash.
+
+The following patch fixes the problem.
+
+--- ppp-2.4.6.orig/pppd/plugins/radius/util.c
++++ ppp-2.4.6/pppd/plugins/radius/util.c
+@@ -77,7 +77,7 @@ rc_mksid (void)
+   static unsigned short int cnt = 0;
+   sprintf (buf, "%08lX%04X%02hX",
+ 	   (unsigned long int) time (NULL),
+-	   (unsigned int) getpid (),
++	   (unsigned int) getpid () % 65535,
+ 	   cnt & 0xFF);
+   cnt++;
+   return buf;

meta/recipes-connectivity/ppp/ppp_2.4.7.bb

@@ -29,6 +29,7 @@ SRC_URI = "http://ppp.samba.org/ftp/ppp/ppp-${PV}.tar.gz \
            file://provider \
            file://0001-ppp-Fix-compilation-errors-in-Makefile.patch \
            file://ppp@.service \
+           file://fix-CVE-2015-3310.patch \
 "
 
 SRC_URI[md5sum] = "78818f40e6d33a1d1de68a1551f6595a"