crypto: lrw - Fix use-after-free on EINPROGRESS

[Herbert Xu <herbert@gondor.apana.org.au>]

When we get an EINPROGRESS completion in lrw, we will end up marking
the request as done and freeing it.  This then blows up when the
request is really completed as we've already freed the memory.

Fixes: 700cb3f5fe75 ("crypto: lrw - Convert to skcipher")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/lrw.c b/crypto/lrw.c
index 3ea095a..a8bfae4 100644
--- a/crypto/lrw.c
+++ b/crypto/lrw.c
@@ -345,6 +345,13 @@ static void encrypt_done(struct crypto_async_request *areq, int err)
 	struct rctx *rctx;
 
 	rctx = skcipher_request_ctx(req);
+
+	if (err == -EINPROGRESS) {
+		if (rctx->left != req->cryptlen)
+			return;
+		goto out;
+	}
+
 	subreq = &rctx->subreq;
 	subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG;
 
@@ -352,6 +359,7 @@ static void encrypt_done(struct crypto_async_request *areq, int err)
 	if (rctx->left)
 		return;
 
+out:
 	skcipher_request_complete(req, err);
 }
 
@@ -389,6 +397,13 @@ static void decrypt_done(struct crypto_async_request *areq, int err)
 	struct rctx *rctx;
 
 	rctx = skcipher_request_ctx(req);
+
+	if (err == -EINPROGRESS) {
+		if (rctx->left != req->cryptlen)
+			return;
+		goto out;
+	}
+
 	subreq = &rctx->subreq;
 	subreq->base.flags &= CRYPTO_TFM_REQ_MAY_BACKLOG;
 
@@ -396,6 +411,7 @@ static void decrypt_done(struct crypto_async_request *areq, int err)
 	if (rctx->left)
 		return;
 
+out:
 	skcipher_request_complete(req, err);
 }
 
-- 
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