[GIT pull] efi fixes for 4.17

From: Thomas Gleixner
Date: Sun May 20 2018 - 03:33:02 EST


Linus,

please pull the latest efi-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git efi-urgent-for-linus

Two EFI fixes:

- Use explicitely sized type for the romimage pointer in the 32bit EFI
protocol struct so a 64bit kernel does not expand it to 64bit. Ditto
for the 64bit struct to avoid the reverse issue on 32bit kernels.

- Handle randomized tex offset correctly in the ARM64 EFI stub to avoid
unaligned data resulting in stack corruption and other hard to diagnose
wreckage.

Thanks,

tglx

------------------>
Ard Biesheuvel (1):
efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode

Mark Rutland (1):
efi/libstub/arm64: Handle randomized TEXT_OFFSET


arch/x86/boot/compressed/eboot.c | 6 ++++--
drivers/firmware/efi/libstub/arm64-stub.c | 10 ++++++++++
include/linux/efi.h | 8 ++++----
3 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 47d3efff6805..09f36c0d9d4f 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -163,7 +163,8 @@ __setup_efi_pci32(efi_pci_io_protocol_32 *pci, struct pci_setup_rom **__rom)
if (status != EFI_SUCCESS)
goto free_struct;

- memcpy(rom->romdata, pci->romimage, pci->romsize);
+ memcpy(rom->romdata, (void *)(unsigned long)pci->romimage,
+ pci->romsize);
return status;

free_struct:
@@ -269,7 +270,8 @@ __setup_efi_pci64(efi_pci_io_protocol_64 *pci, struct pci_setup_rom **__rom)
if (status != EFI_SUCCESS)
goto free_struct;

- memcpy(rom->romdata, pci->romimage, pci->romsize);
+ memcpy(rom->romdata, (void *)(unsigned long)pci->romimage,
+ pci->romsize);
return status;

free_struct:
diff --git a/drivers/firmware/efi/libstub/arm64-stub.c b/drivers/firmware/efi/libstub/arm64-stub.c
index b9bd827caa22..1b4d465cc5d9 100644
--- a/drivers/firmware/efi/libstub/arm64-stub.c
+++ b/drivers/firmware/efi/libstub/arm64-stub.c
@@ -97,6 +97,16 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
u32 offset = !IS_ENABLED(CONFIG_DEBUG_ALIGN_RODATA) ?
(phys_seed >> 32) & mask : TEXT_OFFSET;

+ /*
+ * With CONFIG_RANDOMIZE_TEXT_OFFSET=y, TEXT_OFFSET may not
+ * be a multiple of EFI_KIMG_ALIGN, and we must ensure that
+ * we preserve the misalignment of 'offset' relative to
+ * EFI_KIMG_ALIGN so that statically allocated objects whose
+ * alignment exceeds PAGE_SIZE appear correctly aligned in
+ * memory.
+ */
+ offset |= TEXT_OFFSET % EFI_KIMG_ALIGN;
+
/*
* If KASLR is enabled, and we have some randomness available,
* locate the kernel at a randomized offset in physical memory.
diff --git a/include/linux/efi.h b/include/linux/efi.h
index f1b7d68ac460..3016d8c456bc 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -395,8 +395,8 @@ typedef struct {
u32 attributes;
u32 get_bar_attributes;
u32 set_bar_attributes;
- uint64_t romsize;
- void *romimage;
+ u64 romsize;
+ u32 romimage;
} efi_pci_io_protocol_32;

typedef struct {
@@ -415,8 +415,8 @@ typedef struct {
u64 attributes;
u64 get_bar_attributes;
u64 set_bar_attributes;
- uint64_t romsize;
- void *romimage;
+ u64 romsize;
+ u64 romimage;
} efi_pci_io_protocol_64;

typedef struct {