linux/arch/x86
Kees Cook 2bc1cd39fa x86/boot: Clean up pointer casting
Currently extract_kernel() defines the input and output buffer pointers
as "unsigned char *" since that's effectively what they are. It passes
these to the decompressor routine and to the ELF parser, which both
logically deal with buffer pointers too. There is some casting ("unsigned
long") done to validate the numerical value of the pointers, but it is
relatively limited.

However, choose_random_location() operates almost exclusively on the
numerical representation of these pointers, so it ended up carrying
a lot of "unsigned long" casts. With the future physical/virtual split
these casts were going to multiply, so this attempts to solve the
problem by doing all the casting in choose_random_location()'s entry
and return instead of through-out the code. Adjusts argument names to
be more meaningful, and changes one us of "choice" to "output" to make
the future physical/virtual split more clear (i.e. "choice" should be
strictly a function return value and not used as an intermediate).

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: kernel-hardening@lists.openwall.com
Cc: lasse.collin@tukaani.org
Link: http://lkml.kernel.org/r/1462486436-3707-2-git-send-email-keescook@chromium.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-06 09:00:59 +02:00
..
boot x86/boot: Clean up pointer casting 2016-05-06 09:00:59 +02:00
configs Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2016-03-17 11:33:45 -07:00
crypto Merge branch 'core-objtool-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-20 18:23:21 -07:00
entry Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
events Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-04-03 07:22:12 -05:00
ia32 Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
include x86/paravirt: Remove paravirt_enabled() 2016-04-22 10:29:07 +02:00
kernel x86/boot: Move compressed kernel to the end of the decompression buffer 2016-04-29 11:03:29 +02:00
kvm KVM: x86: mask CPUID(0xD,0x1).EAX against host value 2016-04-10 21:53:50 +02:00
lguest x86/paravirt: Remove paravirt_enabled() 2016-04-22 10:29:07 +02:00
lib Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
math-emu Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
mm x86/KASLR: Drop CONFIG_RANDOMIZE_BASE_MAX_OFFSET 2016-04-22 10:00:50 +02:00
net x86/asm/bpf: Create stack frames in bpf_jit.S 2016-02-24 08:35:44 +01:00
oprofile Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
pci PCI changes for the v4.6 merge window: 2016-03-16 14:45:55 -07:00
platform Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
power x86/asm/power: Create stack frames in hibernate_asm_64.S 2016-02-24 08:35:43 +01:00
purgatory Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-24 09:47:32 -07:00
ras x86/topology: Fix AMD core count 2016-03-29 10:45:04 +02:00
realmode kernel: add kcov code coverage 2016-03-22 15:36:02 -07:00
tools x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size' 2016-04-29 11:03:30 +02:00
um Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2016-03-19 10:05:34 -07:00
video x86/video: Don't assume all FB devices are PCI devices 2016-03-15 11:08:26 +01:00
xen x86/paravirt: Remove paravirt_enabled() 2016-04-22 10:29:07 +02:00
.gitignore
Kbuild perf/x86: Move perf_event.c ............... => x86/events/core.c 2016-02-09 10:23:49 +01:00
Kconfig x86/KASLR: Drop CONFIG_RANDOMIZE_BASE_MAX_OFFSET 2016-04-22 10:00:50 +02:00
Kconfig.cpu x86/Kconfig/cpus: Fix/complete CPU type help texts 2015-10-21 11:12:56 +02:00
Kconfig.debug Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-03-15 09:32:27 -07:00
Makefile x86/init: Rename EBDA code file 2016-04-22 10:29:07 +02:00
Makefile_32.cpu
Makefile.um