From 41ccdbfd5427bbbf3ed58b16750113b38fad1780 Mon Sep 17 00:00:00 2001
From: Daniel Jordan <daniel.m.jordan@oracle.com>
Date: Mon, 10 Feb 2020 13:11:00 -0500
Subject: [PATCH] padata: fix uninitialized return value in padata_replace()
Git-commit: 41ccdbfd5427bbbf3ed58b16750113b38fad1780
References: git-fixes
Patch-mainline: v5.7-rc1

According to Geert's report[0],

  kernel/padata.c: warning: 'err' may be used uninitialized in this
    function [-Wuninitialized]:  => 539:2

Warning is seen only with older compilers on certain archs.  The
runtime effect is potentially returning garbage down the stack when
padata's cpumasks are modified before any pcrypt requests have run.

Simplest fix is to initialize err to the success value.

[0] http://lkml.kernel.org/r/20200210135506.11536-1-geert@linux-m68k.org

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: bbefa1dd6a6d ("crypto: pcrypt - Avoid deadlock by using per-instance padata queues")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 kernel/padata.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -525,7 +525,7 @@ static int padata_replace(struct padata_
 {
 	int notification_mask = 0;
 	struct padata_shell *ps;
-	int err;
+	int err = 0;
 
 	pinst->flags |= PADATA_RESET;