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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2017-06-10 10:12:14 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-06-10 10:12:14 -0700 |
| commit | 9376906c17fa975bf6a7ea9dd124be697bcda289 (patch) | |
| tree | f998d3d0a105daef7e78fc4457d33ce5d0c84e38 /drivers | |
| parent | 179145e6312b1ccb1731841360d7fcaf2f4abc7a (diff) | |
| parent | 792ef14df5c585c19b2831673a077504a09e5203 (diff) | |
| download | linux-9376906c17fa975bf6a7ea9dd124be697bcda289.tar.bz2 | |
Merge branch 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI fix from Ingo Molnar:
"A boot crash fix for certain systems where the kernel would trust a
piece of firmware data it should not have"
* 'efi-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
efi: Fix boot panic because of invalid BGRT image address
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/firmware/efi/efi-bgrt.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/drivers/firmware/efi/efi-bgrt.c b/drivers/firmware/efi/efi-bgrt.c index 8bf27323f7a3..b58233e4ed71 100644 --- a/drivers/firmware/efi/efi-bgrt.c +++ b/drivers/firmware/efi/efi-bgrt.c @@ -27,6 +27,26 @@ struct bmp_header { u32 size; } __packed; +static bool efi_bgrt_addr_valid(u64 addr) +{ + efi_memory_desc_t *md; + + for_each_efi_memory_desc(md) { + u64 size; + u64 end; + + if (md->type != EFI_BOOT_SERVICES_DATA) + continue; + + size = md->num_pages << EFI_PAGE_SHIFT; + end = md->phys_addr + size; + if (addr >= md->phys_addr && addr < end) + return true; + } + + return false; +} + void __init efi_bgrt_init(struct acpi_table_header *table) { void *image; @@ -36,7 +56,7 @@ void __init efi_bgrt_init(struct acpi_table_header *table) if (acpi_disabled) return; - if (!efi_enabled(EFI_BOOT)) + if (!efi_enabled(EFI_MEMMAP)) return; if (table->length < sizeof(bgrt_tab)) { @@ -65,6 +85,10 @@ void __init efi_bgrt_init(struct acpi_table_header *table) goto out; } + if (!efi_bgrt_addr_valid(bgrt->image_address)) { + pr_notice("Ignoring BGRT: invalid image address\n"); + goto out; + } image = early_memremap(bgrt->image_address, sizeof(bmp_header)); if (!image) { pr_notice("Ignoring BGRT: failed to map image header memory\n"); |