libcoap: fix CVE-2024-0962

CVE-2024-0962:

A vulnerability was found in obgm libcoap 4.3.4. It has been rated as critical. Affected by this issue is the function get_split_entry of the file src/coap_oscore.c of the component Configuration File Handler. The manipulation leads to stack-based buffer overflow.

Upstream-Status: Backport [https://github.com/obgm/libcoap/pull/1311]

WARNING: libcoap-4.3.4-r0 do_cve_check: Found unpatched CVE (CVE-2024-0962)

This vulnerability is only exist in 4.3.4.

Signed-off-by: alperak <alperyasinak1@gmail.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

meta-networking/recipes-devtools/libcoap/libcoap/CVE-2024-0962.patch

@@ -0,0 +1,45 @@
+From bf6a303883bde40cf96b960c8574cddd89e71701 Mon Sep 17 00:00:00 2001
+From: Jon Shallow <supjps-libcoap@jpshallow.com>
+Date: Thu, 25 Jan 2024 18:03:17 +0000
+Subject: [PATCH] coap_oscore.c: Fix parsing OSCORE configuration information
+
+A vulnerability was found in obgm libcoap 4.3.4. It has been rated as critical.
+Affected by this issue is the function get_split_entry of the file src/coap_oscore.c of the component Configuration File Handler.
+The manipulation leads to stack-based buffer overflow.
+
+CVE: CVE-2024-0962
+
+Upstream-Status: Backport [https://github.com/obgm/libcoap/pull/1311]
+
+Signed-off-by: alperak <alperyasinak1@gmail.com>
+---
+ src/coap_oscore.c | 5 +++--
+ 1 file changed, 3 insertions(+), 2 deletions(-)
+
+diff --git a/src/coap_oscore.c b/src/coap_oscore.c
+index 83f785c92..e0fb22947 100644
+--- a/src/coap_oscore.c
++++ b/src/coap_oscore.c
+@@ -1678,11 +1678,12 @@ get_split_entry(const char **start,
+                 oscore_value_t *value) {
+   const char *begin = *start;
+   const char *end;
++  const char *kend;
+   const char *split;
+   size_t i;
+
+ retry:
+-  end = memchr(begin, '\n', size);
++  kend = end = memchr(begin, '\n', size);
+   if (end == NULL)
+     return 0;
+
+@@ -1693,7 +1694,7 @@ get_split_entry(const char **start,
+
+   if (begin[0] == '#' || (end - begin) == 0) {
+     /* Skip comment / blank line */
+-    size -= end - begin + 1;
++    size -= kend - begin + 1;
+     begin = *start;
+     goto retry;
+   }

meta-networking/recipes-devtools/libcoap/libcoap_4.3.4.bb

@@ -9,6 +9,7 @@ LIC_FILES_CHKSUM = "file://LICENSE;md5=1978dbc41673ab1c20e64b287c8317bc"
 
 SRC_URI = "git://github.com/obgm/libcoap.git;branch=main;protocol=https \
            file://run-ptest \
+           file://CVE-2024-0962.patch \
            "
 SRCREV = "5fd2f89ef068214130e5d60b7087ef48711fa615"