@@ -461,19 +461,20 @@ int efi_mem_desc_lookup(u64 phys_addr, efi_memory_desc_t *out_md)
efi_memory_desc_t *md;
if (!efi_enabled(EFI_MEMMAP)) {
- pr_err_once("EFI_MEMMAP is not enabled.\n");
+ pr_warn_once("EFI_MEMMAP is not enabled.\n");
return -EINVAL;
}
- if (!out_md) {
- pr_err_once("out_md is null.\n");
- return -EINVAL;
- }
-
for_each_efi_memory_desc(md) {
u64 size;
u64 end;
+ /* skip bogus entries */
+ if ((md->phys_addr & (EFI_PAGE_SIZE - 1)) ||
+ (md->phys_addr > 0 &&
+ (md->num_pages > (U64_MAX - md->phys_addr + 1) >> EFI_PAGE_SHIFT)))
+ continue;
+
size = md->num_pages << EFI_PAGE_SHIFT;
end = md->phys_addr + size;
if (phys_addr >= md->phys_addr && phys_addr < end) {
@@ -247,9 +247,6 @@ void __init efi_esrt_init(void)
int rc;
phys_addr_t end;
- if (!efi_enabled(EFI_MEMMAP))
- return;
-
pr_debug("esrt-init: loading.\n");
if (!esrt_table_exists())
return;
@@ -263,21 +260,8 @@ void __init efi_esrt_init(void)
return;
}
- max = efi_mem_desc_end(&md);
- if (max < efi.esrt) {
- pr_err("EFI memory descriptor is invalid. (esrt: %p max: %p)\n",
- (void *)efi.esrt, (void *)max);
- return;
- }
-
+ max = efi_mem_desc_end(&md) - efi.esrt;
size = sizeof(*esrt);
- max -= efi.esrt;
-
- if (max < size) {
- pr_err("ESRT header doesn't fit on single memory map entry. (size: %zu max: %zu)\n",
- size, max);
- return;
- }
va = early_memremap(efi.esrt, size);
if (!va) {
The ESRT code currently contains some sanity checks on the memory descriptor it obtains, but these can only trigger when the descriptor is invalid (if at all). So let's drop these checks, and instead, disregard descriptors entirely if the start address is misaligned, or the number of pages reaches beyond the end of the address space. Note that the memory map as a whole could still be inconsistent, i.e., multiple entries might cover the same area, or the address could be outside of the addressable VA space, but validating that goes beyond the scope of these helpers. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> --- drivers/firmware/efi/efi.c | 13 +++++++------ drivers/firmware/efi/esrt.c | 18 +----------------- 2 files changed, 8 insertions(+), 23 deletions(-)