From 81d945772afccc77660374aa6e512184b9107580 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 23 Nov 2015 08:43:23 +0100 Subject: [PATCH] arm64: efi: deal with NULL return value of early_memremap() Add NULL return value checks to two invocations of early_memremap() in the UEFI init code. For the UEFI configuration tables, we just warn since we have a better chance of being able to report the issue in a way that can actually be noticed by a human operator if we don't abort right away. For the UEFI memory map, however, all we can do is panic() since we cannot proceed without a description of memory. Signed-off-by: Ard Biesheuvel Reviewed-by: Matt Fleming Acked-by: Will Deacon Signed-off-by: Catalin Marinas --- arch/arm64/kernel/efi.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c index fe7cd1afa109..96e4b1b7de46 100644 --- a/arch/arm64/kernel/efi.c +++ b/arch/arm64/kernel/efi.c @@ -127,7 +127,11 @@ static int __init uefi_init(void) table_size = sizeof(efi_config_table_64_t) * efi.systab->nr_tables; config_tables = early_memremap(efi_to_phys(efi.systab->tables), table_size); - + if (config_tables == NULL) { + pr_warn("Unable to map EFI config table array.\n"); + retval = -ENOMEM; + goto out; + } retval = efi_config_parse_tables(config_tables, efi.systab->nr_tables, sizeof(efi_config_table_64_t), NULL); @@ -209,6 +213,14 @@ void __init efi_init(void) PAGE_ALIGN(params.mmap_size + (params.mmap & ~PAGE_MASK))); memmap.phys_map = params.mmap; memmap.map = early_memremap(params.mmap, params.mmap_size); + if (memmap.map == NULL) { + /* + * If we are booting via UEFI, the UEFI memory map is the only + * description of memory we have, so there is little point in + * proceeding if we cannot access it. + */ + panic("Unable to map EFI memory map.\n"); + } memmap.map_end = memmap.map + params.mmap_size; memmap.desc_size = params.desc_size; memmap.desc_version = params.desc_ver; -- 2.20.1