crypto: ccp - Prevent information leakage on export

commit f709b45ec461b548c41a00044dba1f1b572783bf upstream.

Prevent information from leaking to userspace by doing a memset to 0 of
the export state structure before setting the structure values and copying
it. This prevents un-initialized padding areas from being copied into the
export area.

Reported-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
index 5c93afb1841a614ee9d19733884fb60fd1f4e793..f10b4998937d17aac7dd1b35e283f784be4dfdbc 100644 (file)
--- a/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
+++ b/drivers/crypto/ccp/ccp-crypto-aes-cmac.c
@@ -206,6 +206,9 @@ static int ccp_aes_cmac_export(struct ahash_request *req, void *out)
        struct ccp_aes_cmac_req_ctx *rctx = ahash_request_ctx(req);
        struct ccp_aes_cmac_exp_ctx state;
 
+       /* Don't let anything leak to 'out' */
+       memset(&state, 0, sizeof(state));
+
        state.null_msg = rctx->null_msg;
        memcpy(state.iv, rctx->iv, sizeof(state.iv));
        state.buf_count = rctx->buf_count;

diff --git a/drivers/crypto/ccp/ccp-crypto-sha.c b/drivers/crypto/ccp/ccp-crypto-sha.c
index bdbb5865a50f7f0bcfb678746f11cc2443a3b804..c5b393694dfe5f15df557a1d30e48f76936f038f 100644 (file)
--- a/drivers/crypto/ccp/ccp-crypto-sha.c
+++ b/drivers/crypto/ccp/ccp-crypto-sha.c
@@ -262,6 +262,9 @@ static int ccp_sha_export(struct ahash_request *req, void *out)
        struct ccp_sha_req_ctx *rctx = ahash_request_ctx(req);
        struct ccp_sha_exp_ctx state;
 
+       /* Don't let anything leak to 'out' */
+       memset(&state, 0, sizeof(state));
+
        state.type = rctx->type;
        state.msg_bits = rctx->msg_bits;
        state.first = rctx->first;