efi: Avoid potential crashes, fix the 'struct efi_pci_io_protocol_32' definition for mixed mode
commit 0b3225ab9407f557a8e20f23f37aa7236c10a9b1 upstream.
Mixed mode allows a kernel built for x86_64 to interact with 32-bit
EFI firmware, but requires us to define all struct definitions carefully
when it comes to pointer sizes.
'struct efi_pci_io_protocol_32' currently uses a 'void *' for the
'romimage' field, which will be interpreted as a 64-bit field
on such kernels, potentially resulting in bogus memory references
and subsequent crashes.
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20180504060003.19618-13-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/efi.h b/include/linux/efi.h
index cba7177..80b1b8f 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -380,8 +380,8 @@
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 {
@@ -400,8 +400,8 @@
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 {