Commit 61fe0504 authored by Cui GaoSheng's avatar Cui GaoSheng
Browse files

efi/libstub: add checking validity of memory regions 

hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IASWEC



--------------------------------

Add checking validity of memory regions when memmap is enabled in
cmdline, and print error logs when memory region is invalid.

Fixes: 68684c9c ("efi/libstub: arm64: Fix KASLR and memmap= collision")
Signed-off-by: default avatarCui GaoSheng <cuigaosheng1@huawei.com>
parent 81a41d2a

drivers/firmware/efi/libstub/randomalloc.c

+28 −0
Original line number Diff line number Diff line
@@ -107,6 +107,33 @@ static unsigned long cal_slots_avoid_overlap(efi_memory_desc_t *md, unsigned lon 
	return total_slots;

}



static void mem_check_memmaps(void)

{

	int i;

	efi_status_t status;

	unsigned long nr_pages;

	unsigned long long start, end;



	for (i = 0; i < MAX_MEMMAP_REGIONS; i++) {

		if (!mem_avoid[i].size)

			continue;

		start = round_down(mem_avoid[i].start, EFI_ALLOC_ALIGN);

		end = round_up(mem_avoid[i].start + mem_avoid[i].size, EFI_ALLOC_ALIGN);

		nr_pages = (end - start) / EFI_PAGE_SIZE;



		mem_avoid[i].start = start;

		mem_avoid[i].size = end - start;

		status = efi_bs_call(allocate_pages, EFI_ALLOCATE_ADDRESS,

				     EFI_LOADER_DATA, nr_pages, &mem_avoid[i].start);

		if (status == EFI_SUCCESS) {

			efi_free(mem_avoid[i].size, mem_avoid[i].start);

		} else {

			mem_avoid[i].size = 0;

			efi_err("Failed to reserve memmap, index: %d, status: %lu\n", i, status);

		}

	}

}



void mem_avoid_memmap(char *str)

{

	static int i;
@@ -137,6 +164,7 @@ void mem_avoid_memmap(char *str) 
		str = k;

		i++;

	}

	mem_check_memmaps();

}



void mem_avoid_mem_nokaslr(char *str)