crypto: user - re-add size check for CRYPTO_MSG_GETALG

Commit 9aa867e46565 ("crypto: user - Add CRYPTO_MSG_DELRNG")
accidentally removed the minimum size check for CRYPTO_MSG_GETALG
netlink messages. This allows userland to send a truncated
CRYPTO_MSG_GETALG message as short as a netlink header only making
crypto_report() operate on uninitialized memory by accessing data
beyond the end of the netlink message.

Fix this be re-adding the minimum required size of CRYPTO_MSG_GETALG
messages to the crypto_msg_min[] array.

Fixes: 9aa867e46565 ("crypto: user - Add CRYPTO_MSG_DELRNG")
Cc: stable@vger.kernel.org	# v4.2
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
index 43fe85f20d577b4f3d1bbd6576b6d752bc578531..7097a3395b2529fd123b2c0b14bcce6992fdee49 100644 (file)
--- a/crypto/crypto_user.c
+++ b/crypto/crypto_user.c
@@ -455,6 +455,7 @@ static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
        [CRYPTO_MSG_NEWALG      - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
        [CRYPTO_MSG_DELALG      - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
        [CRYPTO_MSG_UPDATEALG   - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+       [CRYPTO_MSG_GETALG      - CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
        [CRYPTO_MSG_DELRNG      - CRYPTO_MSG_BASE] = 0,
 };