Hello Michael Halcrow, The patch e5d9cbde6ce0: "[PATCH] eCryptfs: Clean up crypto initialization" from Oct 30, 2006, leads to the following static checker warning: fs/ecryptfs/crypto.c:1625 ecryptfs_process_key_cipher() error: get_random_bytes() 'dummy_key' too small (64 vs 4294967295) fs/ecryptfs/crypto.c 1593 static int 1594 ecryptfs_process_key_cipher(struct crypto_blkcipher **key_tfm, 1595 char *cipher_name, size_t *key_size) 1596 { 1597 char dummy_key[ECRYPTFS_MAX_KEY_BYTES]; 1598 char *full_alg_name = NULL; 1599 int rc; 1600 1601 *key_tfm = NULL; 1602 if (*key_size > ECRYPTFS_MAX_KEY_BYTES) { 1603 rc = -EINVAL; 1604 printk(KERN_ERR "Requested key size is [%zd] bytes; maximum " 1605 "allowable is [%d]\n", *key_size, ECRYPTFS_MAX_KEY_BYTES); 1606 goto out; 1607 } 1608 rc = ecryptfs_crypto_api_algify_cipher_name(&full_alg_name, cipher_name, 1609 "ecb"); 1610 if (rc) 1611 goto out; 1612 *key_tfm = crypto_alloc_blkcipher(full_alg_name, 0, CRYPTO_ALG_ASYNC); 1613 if (IS_ERR(*key_tfm)) { 1614 rc = PTR_ERR(*key_tfm); 1615 printk(KERN_ERR "Unable to allocate crypto cipher with name " 1616 "[%s]; rc = [%d]\n", full_alg_name, rc); 1617 goto out; 1618 } 1619 crypto_blkcipher_set_flags(*key_tfm, CRYPTO_TFM_REQ_WEAK_KEY); 1620 if (*key_size == 0) { 1621 struct blkcipher_alg *alg = crypto_blkcipher_alg(*key_tfm); 1622 1623 *key_size = alg->max_keysize; My concern here is that arc4 has a max_keysize of ARC4_MAX_KEY_SIZE (256). 1624 } 1625 get_random_bytes(dummy_key, *key_size); Potentially leading to memory corruption here. This is static analysis work so I may be wrong. 1626 rc = crypto_blkcipher_setkey(*key_tfm, dummy_key, *key_size); 1627 if (rc) { 1628 printk(KERN_ERR "Error attempting to set key of size [%zd] for " 1629 "cipher [%s]; rc = [%d]\n", *key_size, full_alg_name, 1630 rc); 1631 rc = -EINVAL; 1632 goto out; 1633 } 1634 out: 1635 kfree(full_alg_name); 1636 return rc; 1637 } regards, dan carpenter -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html