diff options
Diffstat (limited to '0002-efi-efi_map_region-traceback-if-we-try-to-map-invali.patch')
| -rw-r--r-- | 0002-efi-efi_map_region-traceback-if-we-try-to-map-invali.patch | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/0002-efi-efi_map_region-traceback-if-we-try-to-map-invali.patch b/0002-efi-efi_map_region-traceback-if-we-try-to-map-invali.patch new file mode 100644 index 000000000..25b0ad19b --- /dev/null +++ b/0002-efi-efi_map_region-traceback-if-we-try-to-map-invali.patch @@ -0,0 +1,71 @@ +From 510cd0c36a3beb0907bdbd31a48b71abdddb44a7 Mon Sep 17 00:00:00 2001 +From: Peter Jones <pjones@redhat.com> +Date: Wed, 7 Dec 2016 16:20:10 -0500 +Subject: [PATCH 2/4] efi: efi_map_region(): traceback if we try to map invalid + sized regions + +Some machines, such as the Lenovo ThinkPad W541 with firmware GNET80WW +(2.28), include memory map entries with phys_addr=0x0 and num_pages=0. +We shouldn't ever try to map these errors, so if we get as far as +efi_map_region(), show a traceback. + +This additionally makes should_map_region() say not to map them, but I +fixed both places in case another caller of efi_map_region() ever arises +in the future. + +Signed-off-by: Peter Jones <pjones@redhat.com> +--- + arch/x86/platform/efi/efi.c | 4 ++++ + arch/x86/platform/efi/efi_64.c | 19 ++++++++++++++++--- + 2 files changed, 20 insertions(+), 3 deletions(-) + +diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c +index 181c915..bf32454 100644 +--- a/arch/x86/platform/efi/efi.c ++++ b/arch/x86/platform/efi/efi.c +@@ -707,6 +707,10 @@ static bool should_map_region(efi_memory_desc_t *md) + if (IS_ENABLED(CONFIG_X86_32)) + return false; + ++ if (md->num_pages == 0 || ++ md->num_pages >= (((u64)-1LL) >> EFI_PAGE_SHIFT)) ++ return false; ++ + /* + * Map all of RAM so that we can access arguments in the 1:1 + * mapping when making EFI runtime calls. +diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c +index de12d9f..f80de01 100644 +--- a/arch/x86/platform/efi/efi_64.c ++++ b/arch/x86/platform/efi/efi_64.c +@@ -283,11 +283,24 @@ static void __init __map_region(efi_memory_desc_t *md, u64 va) + + void __init efi_map_region(efi_memory_desc_t *md) + { +- unsigned long size = md->num_pages << PAGE_SHIFT; ++ u64 size = md->num_pages << PAGE_SHIFT; + u64 pa = md->phys_addr; + +- if (efi_enabled(EFI_OLD_MEMMAP)) +- return old_map_region(md); ++ /* ++ * hah hah the system firmware is having a good one on us ++ */ ++ if (md->num_pages == 0 || ++ md->num_pages >= (((u64)-1LL) >> EFI_PAGE_SHIFT)) { ++ pr_err("memmap from %p to %p is unreasonable. Not mapping it.\n", ++ (void *)pa, (void *)(pa+size)); ++ WARN_ON(1); ++ return; ++ } ++ ++ if (efi_enabled(EFI_OLD_MEMMAP)) { ++ old_map_region(md); ++ return; ++ } + + /* + * Make sure the 1:1 mappings are present as a catch-all for b0rked +-- +2.9.3 + |