From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> Date: Thu, 4 Dec 2014 22:30:20 +0100 The functions crypto_free_blkcipher((), crypto_free_hash() and kfree() could be called in some cases by the mppe_alloc() function during error handling even if the passed data structure element contained still a null pointer. This implementation detail could be improved by adjustments for jump labels. Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> --- drivers/net/ppp/ppp_mppe.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/drivers/net/ppp/ppp_mppe.c b/drivers/net/ppp/ppp_mppe.c index 94ff216..c82198f 100644 --- a/drivers/net/ppp/ppp_mppe.c +++ b/drivers/net/ppp/ppp_mppe.c @@ -196,11 +196,11 @@ static void *mppe_alloc(unsigned char *options, int optlen) if (optlen != CILEN_MPPE + sizeof(state->master_key) || options[0] != CI_MPPE || options[1] != CILEN_MPPE) - goto out; + return NULL; state = kzalloc(sizeof(*state), GFP_KERNEL); if (state == NULL) - goto out; + return NULL; state->arc4 = crypto_alloc_blkcipher("ecb(arc4)", 0, CRYPTO_ALG_ASYNC); @@ -212,16 +212,16 @@ static void *mppe_alloc(unsigned char *options, int optlen) state->sha1 = crypto_alloc_hash("sha1", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(state->sha1)) { state->sha1 = NULL; - goto out_free; + goto out_free_blkcipher; } digestsize = crypto_hash_digestsize(state->sha1); if (digestsize < MPPE_MAX_KEY_LEN) - goto out_free; + goto out_free_hash; state->sha1_digest = kmalloc(digestsize, GFP_KERNEL); if (!state->sha1_digest) - goto out_free; + goto out_free_hash; /* Save keys. */ memcpy(state->master_key, &options[CILEN_MPPE], @@ -236,14 +236,12 @@ static void *mppe_alloc(unsigned char *options, int optlen) return (void *)state; +out_free_hash: + crypto_free_hash(state->sha1); +out_free_blkcipher: + crypto_free_blkcipher(state->arc4); out_free: - kfree(state->sha1_digest); - if (state->sha1) - crypto_free_hash(state->sha1); - if (state->arc4) - crypto_free_blkcipher(state->arc4); kfree(state); -out: return NULL; } -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-ppp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html