diff options
author | Lukasz Odzioba <lukasz.odzioba@intel.com> | 2016-12-28 14:55:40 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@kernel.org> | 2017-01-05 08:54:34 +0100 |
commit | dd853fd216d1485ed3045ff772079cc8689a9a4a (patch) | |
tree | 4b351982ec908b819b9f3dff707fc99f1830d910 /arch/xtensa | |
parent | e02003b515e8d95f40f20f213622bb82510873d2 (diff) | |
download | op-kernel-dev-dd853fd216d1485ed3045ff772079cc8689a9a4a.zip op-kernel-dev-dd853fd216d1485ed3045ff772079cc8689a9a4a.tar.gz |
x86/cpu: Fix bootup crashes by sanitizing the argument of the 'clearcpuid=' command-line option
A negative number can be specified in the cmdline which will be used as
setup_clear_cpu_cap() argument. With that we can clear/set some bit in
memory predceeding boot_cpu_data/cpu_caps_cleared which may cause kernel
to misbehave. This patch adds lower bound check to setup_disablecpuid().
Boris Petkov reproduced a crash:
[ 1.234575] BUG: unable to handle kernel paging request at ffffffff858bd540
[ 1.236535] IP: memcpy_erms+0x6/0x10
Signed-off-by: Lukasz Odzioba <lukasz.odzioba@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: andi.kleen@intel.com
Cc: bp@alien8.de
Cc: dave.hansen@linux.intel.com
Cc: luto@kernel.org
Cc: slaoub@gmail.com
Fixes: ac72e7888a61 ("x86: add generic clearcpuid=... option")
Link: http://lkml.kernel.org/r/1482933340-11857-1-git-send-email-lukasz.odzioba@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/xtensa')
0 files changed, 0 insertions, 0 deletions