From 10a2f0b311094ffd45463a529a410a51ca025f27 Mon Sep 17 00:00:00 2001
From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 2 Oct 2020 17:55:22 +1000
Subject: [PATCH] crypto: bcm - Verify GCM/CCM key length in setkey
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Git-commit: 10a2f0b311094ffd45463a529a410a51ca025f27
Patch-mainline: v5.10-rc1
References: git-fixes

The setkey function for GCM/CCM algorithms didn't verify the key
length before copying the key and subtracting the salt length.

This patch delays the copying of the key til after the verification
has been done.  It also adds checks on the key length to ensure
that it's at least as long as the salt.

Fixes: 9d12ba86f818 ("crypto: brcm - Add Broadcom SPU driver")
Cc: <stable@vger.kernel.org>
Reported-by: kiyin(尹亮) <kiyin@tencent.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/crypto/bcm/cipher.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/bcm/cipher.c b/drivers/crypto/bcm/cipher.c
index 5d38b87b9d77..50d169e61b41 100644
--- a/drivers/crypto/bcm/cipher.c
+++ b/drivers/crypto/bcm/cipher.c
@@ -2867,7 +2867,6 @@ static int aead_gcm_ccm_setkey(struct crypto_aead *cipher,
 
 	ctx->enckeylen = keylen;
 	ctx->authkeylen = 0;
-	memcpy(ctx->enckey, key, ctx->enckeylen);
 
 	switch (ctx->enckeylen) {
 	case AES_KEYSIZE_128:
@@ -2883,6 +2882,8 @@ static int aead_gcm_ccm_setkey(struct crypto_aead *cipher,
 		goto badkey;
 	}
 
+	memcpy(ctx->enckey, key, ctx->enckeylen);
+
 	flow_log("  enckeylen:%u authkeylen:%u\n", ctx->enckeylen,
 		 ctx->authkeylen);
 	flow_dump("  enc: ", ctx->enckey, ctx->enckeylen);
@@ -2937,6 +2938,10 @@ static int aead_gcm_esp_setkey(struct crypto_aead *cipher,
 	struct iproc_ctx_s *ctx = crypto_aead_ctx(cipher);
 
 	flow_log("%s\n", __func__);
+
+	if (keylen < GCM_ESP_SALT_SIZE)
+		return -EINVAL;
+
 	ctx->salt_len = GCM_ESP_SALT_SIZE;
 	ctx->salt_offset = GCM_ESP_SALT_OFFSET;
 	memcpy(ctx->salt, key + keylen - GCM_ESP_SALT_SIZE, GCM_ESP_SALT_SIZE);
@@ -2965,6 +2970,10 @@ static int rfc4543_gcm_esp_setkey(struct crypto_aead *cipher,
 	struct iproc_ctx_s *ctx = crypto_aead_ctx(cipher);
 
 	flow_log("%s\n", __func__);
+
+	if (keylen < GCM_ESP_SALT_SIZE)
+		return -EINVAL;
+
 	ctx->salt_len = GCM_ESP_SALT_SIZE;
 	ctx->salt_offset = GCM_ESP_SALT_OFFSET;
 	memcpy(ctx->salt, key + keylen - GCM_ESP_SALT_SIZE, GCM_ESP_SALT_SIZE);
@@ -2994,6 +3003,10 @@ static int aead_ccm_esp_setkey(struct crypto_aead *cipher,
 	struct iproc_ctx_s *ctx = crypto_aead_ctx(cipher);
 
 	flow_log("%s\n", __func__);
+
+	if (keylen < CCM_ESP_SALT_SIZE)
+		return -EINVAL;
+
 	ctx->salt_len = CCM_ESP_SALT_SIZE;
 	ctx->salt_offset = CCM_ESP_SALT_OFFSET;
 	memcpy(ctx->salt, key + keylen - CCM_ESP_SALT_SIZE, CCM_ESP_SALT_SIZE);
-- 
2.16.4