From: THOBY Simon Simon.THOBY@viveris.fr
commit 8510505d55e194d3f6c9644c9f9d12c4f6b0395a upstream.
MD5 is a weak digest algorithm that shouldn't be used for cryptographic operation. It hinders the efficiency of a patch set that aims to limit the digests allowed for the extended file attribute namely security.ima. MD5 is no longer a requirement for IMA, nor should it be used there.
The sole place where we still use the MD5 algorithm inside IMA is setting the ima_hash algorithm to MD5, if the user supplies 'ima_hash=md5' parameter on the command line. With commit ab60368ab6a4 ("ima: Fallback to the builtin hash algorithm"), setting "ima_hash=md5" fails gracefully when CRYPTO_MD5 is not set: ima: Can not allocate md5 (reason: -2) ima: Allocating md5 failed, going to use default hash algorithm sha256
Remove the CRYPTO_MD5 dependency for IMA.
Signed-off-by: THOBY Simon Simon.THOBY@viveris.fr Reviewed-by: Lakshmi Ramasubramanian nramas@linux.microsoft.com [zohar@linux.ibm.com: include commit number in patch description for stable.] Cc: stable@vger.kernel.org # 4.17 Signed-off-by: Mimi Zohar zohar@linux.ibm.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- security/integrity/ima/Kconfig | 1 - 1 file changed, 1 deletion(-)
--- a/security/integrity/ima/Kconfig +++ b/security/integrity/ima/Kconfig @@ -5,7 +5,6 @@ config IMA select SECURITYFS select CRYPTO select CRYPTO_HMAC - select CRYPTO_MD5 select CRYPTO_SHA1 select CRYPTO_HASH_INFO select TCG_TPM if HAS_IOMEM && !UML