x86/hpet: Prevent potential NULL pointer dereference

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
This commit is contained in:
Aditya Pakki 2019-03-18 21:19:56 -05:00 committed by Thomas Gleixner
parent 725e29db8c
commit 2e84f116af

View File

@ -905,6 +905,8 @@ int __init hpet_enable(void)
return 0; return 0;
hpet_set_mapping(); hpet_set_mapping();
if (!hpet_virt_address)
return 0;
/* /*
* Read the period and check for a sane value: * Read the period and check for a sane value: