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From: Aditya Pakki <pakki001@umn.edu>
To: pakki001@umn.edu
Cc: kjlu@umn.edu, Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	x86@kernel.org, Kees Cook <keescook@chromium.org>,
	Joe Perches <joe@perches.com>, Nicolai Stange <nstange@suse.de>,
	Roland Dreier <roland@purestorage.com>,
	linux-kernel@vger.kernel.org
Subject: [PATCH] x86: hpet: Fix to avoid potential NULL pointer dereference
Date: Mon, 18 Mar 2019 21:19:56 -0500	[thread overview]
Message-ID: <20190319021958.17275-1-pakki001@umn.edu> (raw)

hpet_virt_address may be NULL when ioremap_nocache fails. The patch
checks for such a scenario and avoids NULL pointer dereference.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
---
 arch/x86/kernel/hpet.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index dfd3aca82c61..fb32925a2e62 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -905,6 +905,8 @@ 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:
-- 
2.17.1


             reply	other threads:[~2019-03-19  2:20 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-19  2:19 Aditya Pakki [this message]
2019-03-21 11:29 ` [tip:x86/urgent] x86/hpet: Prevent potential NULL pointer dereference tip-bot for Aditya Pakki

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