releases/3.16.54/ima-fix-hash-algorithm-initialization.patch

From: Boshi Wang <wangboshi@huawei.com>
Date: Fri, 20 Oct 2017 16:01:03 +0800
Subject: ima: fix hash algorithm initialization

commit ebe7c0a7be92bbd34c6ff5b55810546a0ee05bee upstream.

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 <wangboshi@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
 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;