[PATCH] x86-64, x86: don't pass CR2 on alignment faults

Don't pass CR2 address on alignment faults.  They report the address of the
last page fault, which is a information leak.

Fix this for i386 and x86-64 by passing 0 instead.

Pointed out by Zachary Amsden <zach@vmware.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/i386/kernel/traps.c

@@ -475,7 +475,7 @@ DO_ERROR( 9, SIGFPE,  "coprocessor segment overrun", coprocessor_segment_overrun
 DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
 DO_ERROR(11, SIGBUS,  "segment not present", segment_not_present)
 DO_ERROR(12, SIGBUS,  "stack segment", stack_segment)
-DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, get_cr2())
+DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
 
 asmlinkage void do_general_protection(struct pt_regs * regs, long error_code)
 {

arch/x86_64/kernel/traps.c

@@ -463,7 +463,7 @@ DO_ERROR( 7, SIGSEGV, "device not available", device_not_available)
 DO_ERROR( 9, SIGFPE,  "coprocessor segment overrun", coprocessor_segment_overrun)
 DO_ERROR(10, SIGSEGV, "invalid TSS", invalid_TSS)
 DO_ERROR(11, SIGBUS,  "segment not present", segment_not_present)
-DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, get_cr2())
+DO_ERROR_INFO(17, SIGBUS, "alignment check", alignment_check, BUS_ADRALN, 0)
 DO_ERROR(18, SIGSEGV, "reserved", reserved)
 
 #define DO_ERROR_STACK(trapnr, signr, str, name) \