From b9caab7824725758242101b0e9c696c94cb63d10 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com>
Date: Fri, 29 Jun 2018 12:35:42 +0200
Subject: [PATCH] Fix passing mdb_strerror() value to croak()
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croak() expects a sprintf-like format string, mdb_strerror() can
return any arbitrary string, including formatting sequences. This
could trick croak() to access an unitialized memory.

Perl 5.28.0 annotates croak() and building LMDB_File with
-Werror=format-security fails now:

LMDB.xs: In function 'populateStat':
LMDB.xs:118:2: error: format not a string literal and no format arguments [-Werror=format-security]
  croak(mdb_strerror(res));
  ^~~~~

This patch fixes it.

Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 LMDB.xs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/LMDB.xs b/LMDB.xs
index 01c8504..43f13de 100644
--- a/LMDB.xs
+++ b/LMDB.xs
@@ -115,7 +115,7 @@ populateStat(pTHX_ HV** hashptr, int res, MDB_stat *stat)
 {
     HV* RETVAL;
     if(res)
-	croak(mdb_strerror(res));
+	croak("%s", mdb_strerror(res));
     RETVAL = newHV();
     StoreUV("psize", stat->ms_psize);
     StoreUV("depth", stat->ms_depth);
-- 
2.14.4