[3/3] crypto: marvell: initialise struct mv_cesa_ahash_req

Commit Message

Russell King Oct. 9, 2015, 10:29 a.m. UTC

When a AF_ALG fd is accepted a second time (hence hash_accept() is
used), hash_accept_parent() allocates a new private context using
sock_kmalloc().  This context is uninitialised.  After use of the new
fd, we eventually end up with the kernel complaining:

marvell-cesa f1090000.crypto: dma_pool_free cesa_padding, c0627770/0 (bad dma)

where c0627770 is a random address.  Poisoning the memory allocated by
the above sock_kmalloc() produces kernel oopses within the marvell hash
code, particularly the interrupt handling.

The following simplfied call sequence occurs:

hash_accept()
  crypto_ahash_export()
    marvell hash export function
  af_alg_accept()
    hash_accept_parent()	<== allocates uninitialised struct hash_ctx
  crypto_ahash_import()
    marvell hash import function

hash_ctx contains the struct mv_cesa_ahash_req in its req.__ctx member,
and, as the marvell hash import function only partially initialises
this structure, we end up with a lot of members which are left with
whatever data was in memory prior to sock_kmalloc().

Add zero-initialisation of this structure.

Signed-off-by: Russell King <[e-mail]>
---
 drivers/crypto/marvell/hash.c | 6 ++++++
 1 file changed, 6 insertions(+)

Patch

diff --git a/drivers/crypto/marvell/hash.c b/drivers/crypto/marvell/hash.c
index a259aced3b42..699839816505 100644
--- a/drivers/crypto/marvell/hash.c
+++ b/drivers/crypto/marvell/hash.c
@@ -831,6 +831,8 @@  static int mv_cesa_md5_import(struct ahash_request *req, const void *in)
 	unsigned int cache_ptr;
 	int ret;
 
+	memset(creq, 0, sizeof(*creq));
+
 	creq->len = in_state->byte_count;
 	memcpy(creq->state, in_state->hash, digsize);
 	creq->cache_ptr = 0;
@@ -921,6 +923,8 @@  static int mv_cesa_sha1_import(struct ahash_request *req, const void *in)
 	unsigned int cache_ptr;
 	int ret;
 
+	memset(creq, 0, sizeof(*creq));
+
 	creq->len = in_state->count;
 	memcpy(creq->state, in_state->state, digsize);
 	creq->cache_ptr = 0;
@@ -1022,6 +1026,8 @@  static int mv_cesa_sha256_import(struct ahash_request *req, const void *in)
 	unsigned int cache_ptr;
 	int ret;
 
+	memset(creq, 0, sizeof(*creq));
+
 	creq->len = in_state->count;
 	memcpy(creq->state, in_state->state, digsize);
 	creq->cache_ptr = 0;