From: Rusty Russell <rusty@rustcorp.com.au>
Date: Fri, 16 Oct 2015 19:42:40 +0000 (+1030)
Subject: tal/str: fix error in tal_strndup()
X-Git-Url: http://git.ozlabs.org/?p=ccan;a=commitdiff_plain;h=28681e0a15c453e86528ca488415e2220cbe0f0a

tal/str: fix error in tal_strndup()

It used strlen() on the source, which might not be valid.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---

diff --git a/ccan/tal/str/str.c b/ccan/tal/str/str.c
index 059817b6..83dac663 100644
--- a/ccan/tal/str/str.c
+++ b/ccan/tal/str/str.c
@@ -26,11 +26,9 @@ char *tal_strndup(const tal_t *ctx, const char *p, size_t n)
 	char *ret;
 
 	/* We have to let through NULL for take(). */
-	if (likely(p)) {
-		len = strlen(p);
-		if (len > n)
-			len = n;
-	} else
+	if (likely(p))
+		len = strnlen(p, n);
+	else
 		len = n;
 
 	ret = tal_dup_(ctx, p, 1, len, 1, false, TAL_LABEL(char, "[]"));
diff --git a/ccan/tal/str/test/run-strndup.c b/ccan/tal/str/test/run-strndup.c
new file mode 100644
index 00000000..d9673548
--- /dev/null
+++ b/ccan/tal/str/test/run-strndup.c
@@ -0,0 +1,22 @@
+#include <ccan/tal/str/str.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <ccan/tal/str/str.c>
+#include <ccan/tap/tap.h>
+#include "helper.h"
+
+int main(int argc, char *argv[])
+{
+	char *str, *copy;
+
+	plan_tests(1);
+	str = malloc(5);
+	memcpy(str, "hello", 5);
+	/* We should be fine to strndup src without nul terminator. */
+	copy = tal_strndup(NULL, str, 5);
+	ok1(!strcmp(copy, "hello"));
+	tal_free(copy);
+	free(str);
+
+	return exit_status();
+}