curl: CVE-2016-8619

double-free in krb5 code

Affected versions: curl 7.3 to and including 7.50.3
Reference:
https://curl.haxx.se/docs/adv_20161102E.html

(From OE-Core rev: 4e18b8af45e1e7769842952f773ba71276e24372)

Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-support/curl/curl/CVE-2016-8619.patch

@@ -0,0 +1,52 @@
+From 91239f7040b1f026d4d15765e7e3f58e92e93761 Mon Sep 17 00:00:00 2001
+From: Daniel Stenberg <daniel@haxx.se>
+Date: Wed, 28 Sep 2016 12:56:02 +0200
+Subject: [PATCH] krb5: avoid realloc(0)
+
+If the requested size is zero, bail out with error instead of doing a
+realloc() that would cause a double-free: realloc(0) acts as a free()
+and then there's a second free in the cleanup path.
+
+CVE: CVE-2016-8619
+Upstream-Status: Backport
+
+Bug: https://curl.haxx.se/docs/adv_20161102E.html
+Reported-by: Cure53
+Signed-off-by: Sona Sarmadi <sona.sarmadi@enea.com>
+---
+ lib/security.c | 9 ++++++---
+ 1 file changed, 6 insertions(+), 3 deletions(-)
+
+diff --git a/lib/security.c b/lib/security.c
+index a268d4a..4cef8f8 100644
+--- a/lib/security.c
++++ b/lib/security.c
+@@ -190,19 +190,22 @@ socket_write(struct connectdata *conn, curl_socket_t fd, const void *to,
+ static CURLcode read_data(struct connectdata *conn,
+                           curl_socket_t fd,
+                           struct krb5buffer *buf)
+ {
+   int len;
+-  void* tmp;
++  void *tmp = NULL;
+   CURLcode result;
+ 
+   result = socket_read(fd, &len, sizeof(len));
+   if(result)
+     return result;
+ 
+-  len = ntohl(len);
+-  tmp = realloc(buf->data, len);
++  if(len) {
++    /* only realloc if there was a length */
++    len = ntohl(len);
++    tmp = realloc(buf->data, len);
++  }
+   if(tmp == NULL)
+     return CURLE_OUT_OF_MEMORY;
+ 
+   buf->data = tmp;
+   result = socket_read(fd, buf->data, len);
+-- 
+2.9.3
+

meta/recipes-support/curl/curl_7.47.1.bb

@@ -19,6 +19,7 @@ SRC_URI += " file://configure_ac.patch \
              file://CVE-2016-8616.patch \
              file://CVE-2016-8617.patch \
              file://CVE-2016-8618.patch \
+             file://CVE-2016-8619.patch \
            "
 
 SRC_URI[md5sum] = "9ea3123449439bbd960cd25cf98796fb"