[PATCH] x86/power/64: Avoid memory corruption in 64-bit swsusp_arch_resume()

From: Rafael J. Wysocki
Date: Fri Jun 17 2016 - 19:29:38 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Commit 70595b479ce1 (x86/power/64: Fix crash whan the hibernation
code passes control to the image kernel) forgot to update the last
argument of memcpy() in swsusp_arch_resume() to reflect the other
changes made by it and that may lead to memory corruption if the
core_restore_code code happens to be located at the end of a page,
so fix it.

Fixes: 70595b479ce1 (x86/power/64: Fix crash whan the hibernation code passes control to the image kernel)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---

Commit 70595b479ce1 is in tip and linux-next now.

---
arch/x86/power/hibernate_64.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

Index: linux-pm/arch/x86/power/hibernate_64.c
===================================================================
--- linux-pm.orig/arch/x86/power/hibernate_64.c
+++ linux-pm/arch/x86/power/hibernate_64.c
@@ -142,8 +142,7 @@ int swsusp_arch_resume(void)
relocated_restore_code = (void *)get_safe_page(GFP_ATOMIC);
if (!relocated_restore_code)
return -ENOMEM;
- memcpy(relocated_restore_code, &core_restore_code,
- &restore_registers - &core_restore_code);
+ memcpy(relocated_restore_code, &core_restore_code, PAGE_SIZE);

restore_image();
return 0;