current/SOURCES/gnutls-CVE-2021-4209.patch

From 3db352734472d851318944db13be73da61300568 Mon Sep 17 00:00:00 2001
From: Daiki Ueno <ueno@gnu.org>
Date: Wed, 22 Dec 2021 09:12:25 +0100
Subject: [PATCH] wrap_nettle_hash_fast: avoid calling _update with zero-length
 input

As Nettle's hash update functions internally call memcpy, providing
zero-length input may cause undefined behavior.

Signed-off-by: Daiki Ueno <ueno@gnu.org>
---
 lib/nettle/mac.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/nettle/mac.c b/lib/nettle/mac.c
index f9d4d7a8df..35e070fab0 100644
--- a/lib/nettle/mac.c
+++ b/lib/nettle/mac.c
@@ -788,7 +788,9 @@ static int wrap_nettle_hash_fast(gnutls_digest_algorithm_t algo,
        if (ret < 0)
                return gnutls_assert_val(ret);
 
-       ctx.update(&ctx, text_size, text);
+       if (text_size > 0) {
+               ctx.update(&ctx, text_size, text);
+       }
        ctx.digest(&ctx, ctx.length, digest);
 
        return 0;
-- 
GitLab

1	From 3db352734472d851318944db13be73da61300568 Mon Sep 17 00:00:00 2001
2	From: Daiki Ueno <ueno@gnu.org>
3	Date: Wed, 22 Dec 2021 09:12:25 +0100
4	Subject: [PATCH] wrap_nettle_hash_fast: avoid calling _update with zero-length
5	input
6
7	As Nettle's hash update functions internally call memcpy, providing
8	zero-length input may cause undefined behavior.
9
10	Signed-off-by: Daiki Ueno <ueno@gnu.org>
11	---
12	lib/nettle/mac.c \| 4 +++-
13	1 file changed, 3 insertions(+), 1 deletion(-)
14
15	diff --git a/lib/nettle/mac.c b/lib/nettle/mac.c
16	index f9d4d7a8df..35e070fab0 100644
17	--- a/lib/nettle/mac.c
18	+++ b/lib/nettle/mac.c
19	@@ -788,7 +788,9 @@ static int wrap_nettle_hash_fast(gnutls_digest_algorithm_t algo,
20	if (ret < 0)
21	return gnutls_assert_val(ret);
22
23	- ctx.update(&ctx, text_size, text);
24	+ if (text_size > 0) {
25	+ ctx.update(&ctx, text_size, text);
26	+ }
27	ctx.digest(&ctx, ctx.length, digest);
28
29	return 0;
30	--
31	GitLab
32