From: Aditya Pakki <pakki001@umn.edu>
Date: Mon, 18 Mar 2019 21:19:56 -0500
Subject: x86/hpet: Prevent potential NULL pointer dereference
Git-commit: 2e84f116afca3719c9d0a1a78b47b48f75fd5724
Patch-mainline: 5.1-rc2
References: git-fixes
hpet_virt_address may be NULL when ioremap_nocache fail, but the code lacks
a check.
Add a check to prevent NULL pointer dereference.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: kjlu@umn.edu
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Joe Perches <joe@perches.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: Roland Dreier <roland@purestorage.com>
Link: https://lkml.kernel.org/r/20190319021958.17275-1-pakki001@umn.edu
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/x86/kernel/hpet.c | 2 ++
1 file changed, 2 insertions(+)
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -913,6 +913,8 @@ int __init hpet_enable(void)
return 0;
hpet_set_mapping();
+ if (!hpet_virt_address)
+ return 0;
/*
* Read the period and check for a sane value: