[PATCH] certs: Redirect openssl error message to null device

From: Stefan Berger <stefanb@linux.ibm.com>

Address the following issue detected by the kernel test robot when
there's no certificate file at the time when checking for the type
of key in the cert:

Can't open certs/signing_key.pem for reading, No such file or directory

The simplest solution is to redirect openssl's stderr output to /dev/null.

Fixes: 28d62d945ded ("certs: Trigger creation of RSA module signing key if it's not an RSA key")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reported-by: kernel test robot <redacted>
---
 certs/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/certs/Makefile b/certs/Makefile
index 72758684d254..e7ae3bd3be4a 100644
--- a/certs/Makefile
+++ b/certs/Makefile

@@ -65,7 +65,7 @@ openssl_available       = $(shell openssl help 2>/dev/null && echo yes)
 ifeq ($(CONFIG_MODULE_SIG_KEY),"certs/signing_key.pem")
 
 ifeq ($(openssl_available),yes)
-X509TEXT=$(shell openssl x509 -in $(CONFIG_MODULE_SIG_KEY) -text)
+X509TEXT=$(shell openssl x509 -in $(CONFIG_MODULE_SIG_KEY) -text 2>/dev/null)
 
 $(if $(findstring rsaEncryption,$(X509TEXT)),,$(shell rm -f $(CONFIG_MODULE_SIG_KEY)))
 endif

-- 
2.31.1