From: Matthew DeVore <matvore@google.com>
To: git@vger.kernel.org
Cc: Matthew DeVore <matvore@google.com>,
sandals@crustytoothpaste.net, jeffhostetler@microsoft.com,
l.s.r@web.de, gitster@pobox.com, spearce@spearce.org,
jrn@google.com
Subject: [PATCH v2 2/2] url: do not allow %00 to represent NUL in URLs
Date: Tue, 4 Jun 2019 10:57:05 -0700 [thread overview]
Message-ID: <d3d6316a2aa4691c630b1bb2db6c3ac706aaaa31.1559670300.git.matvore@google.com> (raw)
In-Reply-To: <cover.1559670300.git.matvore@google.com>
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.
Helped-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Matthew DeVore <matvore@google.com>
---
url.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/url.c b/url.c
index 9ea9d5611b..1b8ef78cea 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 < 0 || 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
--
2.21.0
next prev parent reply other threads:[~2019-06-04 17:57 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-06-04 17:57 [PATCH v2 0/2] Harden url.c URL-decoding logic Matthew DeVore
2019-06-04 17:57 ` [PATCH v2 1/2] url: do not read past end of buffer Matthew DeVore
2019-06-04 20:27 ` Junio C Hamano
2019-06-04 17:57 ` Matthew DeVore [this message]
2019-06-04 21:13 ` [PATCH v2 0/2] Harden url.c URL-decoding logic Matthew DeVore
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