[PATCH 3.18 18/26] ima: fix hash algorithm initialization

[Greg Kroah-Hartman]

3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Boshi Wang <wangbo...@huawei.com>


[ Upstream commit ebe7c0a7be92bbd34c6ff5b55810546a0ee05bee ]

The hash_setup function always sets the hash_setup_done flag, even
when the hash algorithm is invalid.  This prevents the default hash
algorithm defined as CONFIG_IMA_DEFAULT_HASH from being used.

This patch sets hash_setup_done flag only for valid hash algorithms.

Fixes: e7a2ad7eb6f4 "ima: enable support for larger default filedata hash 
algorithms"
Signed-off-by: Boshi Wang <wangbo...@huawei.com>
Signed-off-by: Mimi Zohar <zo...@linux.vnet.ibm.com>
Signed-off-by: Sasha Levin <alexander.le...@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 security/integrity/ima/ima_main.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/security/integrity/ima/ima_main.c
+++ b/security/integrity/ima/ima_main.c
@@ -52,6 +52,8 @@ static int __init hash_setup(char *str)
                        ima_hash_algo = HASH_ALGO_SHA1;
                else if (strncmp(str, "md5", 3) == 0)
                        ima_hash_algo = HASH_ALGO_MD5;
+               else
+                       return 1;
                goto out;
        }
 
@@ -61,6 +63,8 @@ static int __init hash_setup(char *str)
                        break;
                }
        }
+       if (i == HASH_ALGO__LAST)
+               return 1;
 out:
        hash_setup_done = 1;
        return 1;