All of lore.kernel.org
 help / color / mirror / Atom feed
From: Herbert Xu <herbert@gondor.apana.org.au>
To: Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
	Harald Freudenberger <freude@linux.ibm.com>,
	linux-s390@vger.kernel.org,
	Gerald Schaefer <gerald.schaefer@de.ibm.com>,
	Jan Glauber <jang@linux.vnet.ibm.com>
Subject: crypto: s390/aes - Fix buffer overread in CTR mode
Date: Tue, 28 Nov 2023 14:22:13 +0800	[thread overview]
Message-ID: <ZWWHFeOPcW30OYo1@gondor.apana.org.au> (raw)

When processing the last block, the s390 ctr code will always read
a whole block, even if there isn't a whole block of data left.  Fix
this by using the actual length left and copy it into a buffer first
for processing.

Fixes: 0200f3ecc196 ("crypto: s390 - add System z hardware support for CTR mode")
Cc: <stable@vger.kernel.org>
Reported-by: Guangwu Zhang <guazhang@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
index c773820e4af9..c6fe5405de4a 100644
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -597,7 +597,9 @@ static int ctr_aes_crypt(struct skcipher_request *req)
 	 * final block may be < AES_BLOCK_SIZE, copy only nbytes
 	 */
 	if (nbytes) {
-		cpacf_kmctr(sctx->fc, sctx->key, buf, walk.src.virt.addr,
+		memset(buf, 0, AES_BLOCK_SIZE);
+		memcpy(buf, walk.src.virt.addr, nbytes);
+		cpacf_kmctr(sctx->fc, sctx->key, buf, buf,
 			    AES_BLOCK_SIZE, walk.iv);
 		memcpy(walk.dst.virt.addr, buf, nbytes);
 		crypto_inc(walk.iv, AES_BLOCK_SIZE);
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

             reply	other threads:[~2023-11-28  6:22 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-11-28  6:22 Herbert Xu [this message]
2023-11-28 11:18 ` crypto: s390/aes - Fix buffer overread in CTR mode Harald Freudenberger
2023-11-28 13:18 ` Harald Freudenberger
2023-12-08  4:06   ` Herbert Xu

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=ZWWHFeOPcW30OYo1@gondor.apana.org.au \
    --to=herbert@gondor.apana.org.au \
    --cc=freude@linux.ibm.com \
    --cc=gerald.schaefer@de.ibm.com \
    --cc=jang@linux.vnet.ibm.com \
    --cc=linux-crypto@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.