libubox: backport security patches

This backports some security relevant patches from libubox master. These
patches should not change the existing API and ABI so that old
applications still work like before without any recompilation.
Application can now also use more secure APIs.

The new more secure interfaces are also available, but not used.

OpenWrt master and 19.07 already have these patches by using a more
recent libubox version.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

1 files changed, 61 insertions, 0 deletions

diff --git a/package/libs/libubox/patches/0012-jshn-prefer-snprintf-usage.patch b/package/libs/libubox/patches/0012-jshn-prefer-snprintf-usage.patch
new file mode 100644
index 0000000000..e551fed7ea
--- /dev/null
+++ b/package/libs/libubox/patches/0012-jshn-prefer-snprintf-usage.patch
@@ -0,0 +1,61 @@
+From 31778937b4153492955495e550435c8bbf7cfde8 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Petr=20=C5=A0tetiar?= <ynezz@true.cz>
+Date: Tue, 14 Jan 2020 08:55:34 +0100
+Subject: jshn: prefer snprintf usage
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Better safe than sorry.
+
+Reviewed-by: Jo-Philipp Wich <jo@mein.io>
+Signed-off-by: Petr Štetiar <ynezz@true.cz>
+---
+ jshn.c | 16 +++++++++-------
+ 1 file changed, 9 insertions(+), 7 deletions(-)
+
+--- a/jshn.c
++++ b/jshn.c
+@@ -68,7 +68,7 @@ static int add_json_array(struct array_l
+ 	int ret;
+ 
+ 	for (i = 0, len = array_list_length(a); i < len; i++) {
+-		sprintf(seq, "%d", i);
++		snprintf(seq, sizeof(seq), "%d", i);
+ 		ret = add_json_element(seq, array_list_get_idx(a, i));
+ 		if (ret)
+ 			return ret;
+@@ -197,25 +197,27 @@ static char *getenv_avl(const char *key)
+ static char *get_keys(const char *prefix)
+ {
+ 	char *keys;
++	size_t len = var_prefix_len + strlen(prefix) + sizeof("K_") + 1;
+ 
+-	keys = alloca(var_prefix_len + strlen(prefix) + sizeof("K_") + 1);
+-	sprintf(keys, "%sK_%s", var_prefix, prefix);
++	keys = alloca(len);
++	snprintf(keys, len, "%sK_%s", var_prefix, prefix);
+ 	return getenv_avl(keys);
+ }
+ 
+ static void get_var(const char *prefix, const char **name, char **var, char **type)
+ {
+ 	char *tmpname, *varname;
++	size_t len = var_prefix_len + strlen(prefix) + 1 + strlen(*name) + 1 + sizeof("T_");
+ 
+-	tmpname = alloca(var_prefix_len + strlen(prefix) + 1 + strlen(*name) + 1 + sizeof("T_"));
++	tmpname = alloca(len);
+ 
+-	sprintf(tmpname, "%s%s_%s", var_prefix, prefix, *name);
++	snprintf(tmpname, len, "%s%s_%s", var_prefix, prefix, *name);
+ 	*var = getenv_avl(tmpname);
+ 
+-	sprintf(tmpname, "%sT_%s_%s", var_prefix, prefix, *name);
++	snprintf(tmpname, len, "%sT_%s_%s", var_prefix, prefix, *name);
+ 	*type = getenv_avl(tmpname);
+ 
+-	sprintf(tmpname, "%sN_%s_%s", var_prefix, prefix, *name);
++	snprintf(tmpname, len, "%sN_%s_%s", var_prefix, prefix, *name);
+ 	varname = getenv_avl(tmpname);
+ 	if (varname)
+ 		*name = varname;