Commit 705d01c8 authored by Ethan Tidmore's avatar Ethan Tidmore Committed by Wei Liu
Browse files

x86/hyperv: Fix error pointer dereference 



The function idle_thread_get() can return an error pointer and is not
checked for it. Add check for error pointer.

Detected by Smatch:
arch/x86/hyperv/hv_vtl.c:126 hv_vtl_bringup_vcpu() error:
'idle' dereferencing possible ERR_PTR()

Fixes: 2b4b90e0 ("x86/hyperv: Use per cpu initial stack for vtl context")
Signed-off-by: default avatarEthan Tidmore <ethantidmore06@gmail.com>
Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
parent fe9f1598

arch/x86/hyperv/hv_vtl.c

+5 −3
Original line number Diff line number Diff line
@@ -110,7 +110,7 @@ static void hv_vtl_ap_entry(void) 


static int hv_vtl_bringup_vcpu(u32 target_vp_index, int cpu, u64 eip_ignored)

{

	u64 status;

	u64 status, rsp, rip;

	int ret = 0;

	struct hv_enable_vp_vtl *input;

	unsigned long irq_flags;
@@ -123,9 +123,11 @@ static int hv_vtl_bringup_vcpu(u32 target_vp_index, int cpu, u64 eip_ignored) 
	struct desc_struct *gdt;



	struct task_struct *idle = idle_thread_get(cpu);

	u64 rsp = (unsigned long)idle->thread.sp;

	if (IS_ERR(idle))

		return PTR_ERR(idle);



	u64 rip = (u64)&hv_vtl_ap_entry;

	rsp = (unsigned long)idle->thread.sp;

	rip = (u64)&hv_vtl_ap_entry;



	native_store_gdt(&gdt_ptr);

	store_idt(&idt_ptr);