From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Javier Martinez Canillas <javierm@redhat.com>
Date: Wed, 15 May 2019 01:46:00 +0200
Subject: [PATCH] blscfg: Don't leave grub_errno set to an error if the command
 succeeded

After a command is executed, the function grub_print_error() is called to
print any active error messages if these exist.

The blscfg command calls to the grub_strtol() function to try to convert
the default entry string to a number, in case the default is an index.

If this function is not able to do the conversion, it sets the grub_errno
variable to GRUB_ERR_BAD_NUMBER. But the blscfg command wrongly left that
set and so the caller would be confused thinking that the command failed
and that an error message has to be printed.

This caused the first error in the stack to be printed, polluting the GRUB
output and preventing the menu to be hidden. So reset the grub_error var
to GRUB_ERR_NONE again if was set to GRUB_ERR_BAD_NUMBER by grub_strtol().

Resolves: rhbz#1699761

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---
 grub-core/commands/blscfg.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/grub-core/commands/blscfg.c b/grub-core/commands/blscfg.c
index bd008b04bec..26dbe873fe4 100644
--- a/grub-core/commands/blscfg.c
+++ b/grub-core/commands/blscfg.c
@@ -999,8 +999,10 @@ is_default_entry(const char *def_entry, struct bls_entry *entry, int idx)
     return true;
 
   def_idx = (int)grub_strtol(def_entry, NULL, 0);
-  if (grub_errno == GRUB_ERR_BAD_NUMBER)
+  if (grub_errno == GRUB_ERR_BAD_NUMBER) {
+    grub_errno = GRUB_ERR_NONE;
     return false;
+  }
 
   if (def_idx == idx)
     return true;