[ Upstream commit 2e84f116afca3719c9d0a1a78b47b48f75fd5724 ] 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 <pakki...@umn.edu> Signed-off-by: Thomas Gleixner <t...@linutronix.de> Cc: k...@umn.edu Cc: Borislav Petkov <b...@alien8.de> Cc: "H. Peter Anvin" <h...@zytor.com> Cc: Kees Cook <keesc...@chromium.org> Cc: Joe Perches <j...@perches.com> Cc: Nicolai Stange <nsta...@suse.de> Cc: Roland Dreier <rol...@purestorage.com> Link: https://lkml.kernel.org/r/20190319021958.17275-1-pakki...@umn.edu Signed-off-by: Sasha Levin <sas...@kernel.org> --- 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 b0acb22e5a46..1e3f1f140ffb 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -909,6 +909,8 @@ 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: -- 2.19.1
