File dshbak-fix-uninitialized-use-of-tag-on-empty-input.patch of Package pdsh.27582

From: Mark A. Grondona <mark.grondona@gmail.com>
Date: Wed Aug 11 15:26:10 2021 -0700
Subject: dshbak: fix uninitialized use of $tag on empty input
Patch-mainline: Not yet
Git-repo: https://github.com/chaos/pdsh
Git-commit: b32d9d312b52447a68d1ee52fbbe0394f857d87a
References: 

Problem: The fix for hostnames of `0` in dshbak, i.e. the
following commit

 commit dee6adf334376da560afa0f8beebe4cae36d8e7c
 Author: Mark A. Grondona <mgrondona@llnl.gov>
 Date:   Thu Jun 25 13:37:51 2015 -0700

    dshbak: Handle hostname of "0"

    @garlick found that dshbak can't handle the smallest of numbers.
    This is because dshbak skips lines where $tag resolves to false.
    But in perl, 0 is also false.

    What we really want to check for is an "empty" tag, so fix up the
    test to reflect that.

    Resolves #70.

breaks handling of empty input to dshbak, since now the variable
"$tag" can be used when it is uninitialized. The proper fix for
issue #70 was to check if the variable was either uninitialized or
an empty string.

Fixes #132

Signed-off-by: Egbert Eich <eich@suse.de>
---
 scripts/dshbak | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/dshbak b/scripts/dshbak
index a6e17eb..fbb4e71 100755
--- a/scripts/dshbak
+++ b/scripts/dshbak
@@ -112,7 +112,7 @@ sub process_lines
 	while (<>) {
 		my ($tag, $data) = m/^\s*(\S+?)\s*: ?(.*\n)$/;
 		#  Ignore lines that aren't prefixed with a hostname:
-		next unless "$tag" ne "";
+		next unless defined $tag and "$tag" ne "";
 		push(@{$lines{$tag}}, $data);
 	}
 	return %lines;