[PATCH 2/2] url: do not allow %00 to represent NULL in URLs

[Matthew DeVore]

There is no reason to allow %00 to terminate a string, so do not allow it.
Otherwise, we end up returning arbitrary content in the string (that which is
after the %00) which is effectively hidden from callers and can escape sanity
checks and validation, and possible be used in tandem with a security
vulnerability to introduce a payload.

Signed-off-by: Matthew DeVore <matv...@google.com>
---
 url.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/url.c b/url.c
index c0bb4e23c3..cf791cb139 100644
--- a/url.c
+++ b/url.c
@@ -41,21 +41,21 @@ static char *url_decode_internal(const char **query, int 
len,
                if (!c)
                        break;
                if (stop_at && strchr(stop_at, c)) {
                        q++;
                        len--;
                        break;
                }
 
                if (c == '%' && len >= 3) {
                        int val = hex2chr(q + 1);
-                       if (0 <= val) {
+                       if (0 < val) {
                                strbuf_addch(out, val);
                                q += 3;
                                len -= 3;
                                continue;
                        }
                }
 
                if (decode_plus && c == '+')
                        strbuf_addch(out, ' ');
                else
-- 
2.17.1