Openwrt/target/linux/generic/backport-5.4/080-wireguard-0051-crypto-chacha20poly1305-prevent-integer-overflow-on-.patch
Jason A. Donenfeld d540725871 kernel-5.4: backport fd16931a2f51 for chacha neon
Without this patch, the chacha block counter is not incremented on neon
rounds, resulting in incorrect calculations and corrupt packets.

This also switches to using `--no-numbered --zero-commit` so that future
diffs are smaller.

Reported-by: Hans Geiblinger <cybrnook2002@yahoo.com>
Reviewed-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
Cc: David Bauer <mail@david-bauer.net>
Cc: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2021-03-02 09:30:22 +01:00

41 lines
1.5 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Thu, 6 Feb 2020 12:42:01 +0100
Subject: [PATCH] crypto: chacha20poly1305 - prevent integer overflow on large
input
commit c9cc0517bba9f0213f1e55172feceb99e5512daf upstream.
This code assigns src_len (size_t) to sl (int), which causes problems
when src_len is very large. Probably nobody in the kernel should be
passing this much data to chacha20poly1305 all in one go anyway, so I
don't think we need to change the algorithm or introduce larger types
or anything. But we should at least error out early in this case and
print a warning so that we get reports if this does happen and can look
into why anybody is possibly passing it that much data or if they're
accidently passing -1 or similar.
Fixes: d95312a3ccc0 ("crypto: lib/chacha20poly1305 - reimplement crypt_from_sg() routine")
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: stable@vger.kernel.org # 5.5+
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
lib/crypto/chacha20poly1305.c | 3 +++
1 file changed, 3 insertions(+)
--- a/lib/crypto/chacha20poly1305.c
+++ b/lib/crypto/chacha20poly1305.c
@@ -235,6 +235,9 @@ bool chacha20poly1305_crypt_sg_inplace(s
__le64 lens[2];
} b __aligned(16);
+ if (WARN_ON(src_len > INT_MAX))
+ return false;
+
chacha_load_key(b.k, key);
b.iv[0] = 0;