From 73bf20ef3df262026c3470241ae4ac8196943ffa Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers@google.com>
Date: Mon, 18 Jun 2018 10:22:37 -0700
Subject: [PATCH] crypto: vmac - require a block cipher with 128-bit block size
Git-commit: 73bf20ef3df262026c3470241ae4ac8196943ffa
Patch-mainline: v4.19-rc1
References: bsc#1051510
The VMAC template assumes the block cipher has a 128-bit block size, but
it failed to check for that. Thus it was possible to instantiate it
using a 64-bit block size cipher, e.g. "vmac(cast5)", causing
uninitialized memory to be used.
Add the needed check when instantiating the template.
Fixes: f1939f7c5645 ("crypto: vmac - New hash algorithm for intel_txt support")
Cc: <stable@vger.kernel.org> # v2.6.32+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
crypto/vmac.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/crypto/vmac.c b/crypto/vmac.c
index df76a816cfb2..3034454a3713 100644
--- a/crypto/vmac.c
+++ b/crypto/vmac.c
@@ -655,6 +655,10 @@ static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
if (IS_ERR(alg))
return PTR_ERR(alg);
+ err = -EINVAL;
+ if (alg->cra_blocksize != 16)
+ goto out_put_alg;
+
inst = shash_alloc_instance("vmac", alg);
err = PTR_ERR(inst);
if (IS_ERR(inst))
--
2.18.0