kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-22 19:14:51 +00:00
Code Issues Releases Packages Activity
linux/drivers/firmware/efi
History
Yinghai Lu e16752a8d3 efi/libstub: Fix boundary checking in efi_high_alloc() 
commit 7ed620bb34 upstream.

While adding support loading kernel and initrd above 4G to grub2 in legacy
mode, I was referring to efi_high_alloc().
That will allocate buffer for kernel and then initrd, and initrd will
use kernel buffer start as limit.

During testing found two buffers will be overlapped when initrd size is
very big like 400M.

It turns out efi_high_alloc() boundary checking is not right.
end - size will be the new start, and should not compare new
start with max, we need to make sure end is smaller than max.

[ Basically, with the current efi_high_alloc() code it's possible to
  allocate memory above 'max', because efi_high_alloc() doesn't check
  that the tail of the allocation is below 'max'.

  If you have an EFI memory map with a single entry that looks like so,

   [0xc0000000-0xc0004000]

  And want to allocate 0x3000 bytes below 0xc0003000 the current code
  will allocate [0xc0001000-0xc0004000], not [0xc0000000-0xc0003000]
  like you would expect. - Matt ]

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2015-03-23 21:02:50 -04:00
..
libstub efi/libstub: Fix boundary checking in efi_high_alloc() 2015-03-23 21:02:50 -04:00
cper.c ACPI and power management updates for 3.17-rc1 2014-08-06 20:34:19 -07:00
efi-pstore.c efi-pstore: Fix an overflow on 32-bit builds 2014-06-27 07:30:32 +01:00
efi.c efi: Introduce efi_md_typeattr_format() 2014-10-03 18:41:00 +01:00
efivars.c efi: Autoload efivars 2014-07-18 21:24:01 +01:00
Kconfig efi: efistub: Convert into static library 2014-07-18 21:22:19 +01:00
Makefile Revert "efi/x86: efistub: Move shared dependencies to <asm/efi.h>" 2014-09-23 22:01:55 +01:00
reboot.c x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag 2014-07-18 21:23:52 +01:00
runtime-map.c efi: Small leak on error in runtime map code 2015-03-23 21:02:50 -04:00
runtime-wrappers.c efi: Delete the in_nmi() conditional runtime locking 2014-10-03 18:41:03 +01:00
vars.c Merge branch 'next' into efi-next-merge 2014-10-03 22:15:56 +01:00