releases/5.4.60/crypto-algif_aead-fix-uninitialized-ctx-init.patch

From c362525ba3837c6ff77458c991ca25c5d6532ea2 Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Wed, 12 Aug 2020 14:58:25 +0200
Subject: crypto: algif_aead - fix uninitialized ctx->init

From: Ondrej Mosnacek <omosnace@redhat.com>

[ Upstream commit 21dfbcd1f5cbff9cf2f9e7e43475aed8d072b0dd ]

In skcipher_accept_parent_nokey() the whole af_alg_ctx structure is
cleared by memset() after allocation, so add such memset() also to
aead_accept_parent_nokey() so that the new "init" field is also
initialized to zero. Without that the initial ctx->init checks might
randomly return true and cause errors.

While there, also remove the redundant zero assignments in both
functions.

Found via libkcapi testsuite.

Cc: Stephan Mueller <smueller@chronox.de>
Fixes: f3c802a1f300 ("crypto: algif_aead - Only wake up when ctx->more is zero")
Suggested-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 crypto/algif_aead.c     | 6 ------
 crypto/algif_skcipher.c | 7 +------
 2 files changed, 1 insertion(+), 12 deletions(-)

diff --git a/crypto/algif_aead.c b/crypto/algif_aead.c
index d48d2156e6210..43c6aa784858b 100644
--- a/crypto/algif_aead.c
+++ b/crypto/algif_aead.c
@@ -558,12 +558,6 @@ static int aead_accept_parent_nokey(void *private, struct sock *sk)
 
 	INIT_LIST_HEAD(&ctx->tsgl_list);
 	ctx->len = len;
-	ctx->used = 0;
-	atomic_set(&ctx->rcvused, 0);
-	ctx->more = 0;
-	ctx->merge = 0;
-	ctx->enc = 0;
-	ctx->aead_assoclen = 0;
 	crypto_init_wait(&ctx->wait);
 
 	ask->private = ctx;
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index a51ba22fef58f..81c4022285a7c 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -333,6 +333,7 @@ static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
 	ctx = sock_kmalloc(sk, len, GFP_KERNEL);
 	if (!ctx)
 		return -ENOMEM;
+	memset(ctx, 0, len);
 
 	ctx->iv = sock_kmalloc(sk, crypto_skcipher_ivsize(tfm),
 			       GFP_KERNEL);
@@ -340,16 +341,10 @@ static int skcipher_accept_parent_nokey(void *private, struct sock *sk)
 		sock_kfree_s(sk, ctx, len);
 		return -ENOMEM;
 	}
-
 	memset(ctx->iv, 0, crypto_skcipher_ivsize(tfm));
 
 	INIT_LIST_HEAD(&ctx->tsgl_list);
 	ctx->len = len;
-	ctx->used = 0;
-	atomic_set(&ctx->rcvused, 0);
-	ctx->more = 0;
-	ctx->merge = 0;
-	ctx->enc = 0;
 	crypto_init_wait(&ctx->wait);
 
 	ask->private = ctx;
-- 
2.25.1