diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c index 75966afb6251..01d7cd85ef97 100644 --- a/arch/x86/kernel/sys_x86_64.c +++ b/arch/x86/kernel/sys_x86_64.c @@ -112,6 +112,14 @@ static void find_start_end(unsigned long addr, unsigned long flags, *end = task_size_64bit(addr > DEFAULT_MAP_WINDOW); } +static inline unsigned long stack_guard_placement(vm_flags_t vm_flags) +{ + if (vm_flags & VM_SHADOW_STACK) + return PAGE_SIZE; + + return 0; +} + unsigned long arch_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, unsigned long len, unsigned long pgoff, unsigned long flags, vm_flags_t vm_flags) @@ -141,6 +149,7 @@ arch_get_unmapped_area_vmflags(struct file *filp, unsigned long addr, unsigned l info.low_limit = begin; info.high_limit = end; info.align_offset = pgoff << PAGE_SHIFT; + info.start_gap = stack_guard_placement(vm_flags); if (filp) { info.align_mask = get_align_mask(); info.align_offset += get_align_bits(); @@ -190,6 +199,7 @@ get_unmapped_area: info.low_limit = PAGE_SIZE; info.high_limit = get_mmap_base(0); + info.start_gap = stack_guard_placement(vm_flags); /* * If hint address is above DEFAULT_MAP_WINDOW, look for unmapped area