[ 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 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: Sasha Levin sashal@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 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: