[PATCH] crypto: skcipher - Pass statesize for simple lskcipher instances

Herbert Xu
2023-12-21T02:42:57Z

On Mon, Dec 18, 2023 at 06:43:27AM -0800, syzbot wrote:
>
> syzbot found the following issue on:
>
> HEAD commit: 17cb8a20bde6 Add linux-next specific files for 20231215
> git tree: linux-next
> console+strace: https://syzkaller.appspot.com/x/log.txt?x=1129f3b6e80000
> kernel config: https://syzkaller.appspot.com/x/.config?x=ec104439b5dbc583
> dashboard link: https://syzkaller.appspot.com/bug?extid=8ffb0839a24e9c6bfa76
> compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17d23c01e80000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14cfe021e80000

---8<---
When ecb is used to wrap an lskcipher, the statesize isn't set
correctly. Fix this by making the simple instance creator set
the statesize.

Reported-by: syzbot+8ffb0839a24e9c6bfa76@syzkaller.appspotmail.com
Reported-by: Edward Adam Davis <eadavis@qq.com>
Fixes: 662ea18d089b ("crypto: skcipher - Make use of internal state")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/lskcipher.c b/crypto/lskcipher.c
index a06008e112f3..0b6dd8aa21f2 100644
--- a/crypto/lskcipher.c
+++ b/crypto/lskcipher.c
@@ -642,6 +642,7 @@ struct lskcipher_instance *lskcipher_alloc_instance_simple(
inst->alg.co.min_keysize = cipher_alg->co.min_keysize;
inst->alg.co.max_keysize = cipher_alg->co.max_keysize;
inst->alg.co.ivsize = cipher_alg->co.base.cra_blocksize;
+ inst->alg.co.statesize = cipher_alg->co.statesize;

/* Use struct crypto_lskcipher * by default, can be overridden */
inst->alg.co.base.cra_ctxsize = sizeof(struct crypto_lskcipher *);