x86_64: Zero extend all registers after ptrace in 32bit entry path.
authorAndi Kleen <ak@suse.de>
Fri, 21 Sep 2007 14:16:18 +0000 (16:16 +0200)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Fri, 21 Sep 2007 16:52:07 +0000 (09:52 -0700)
commit176df2457ef6207156ca1a40991c54ca01fef567
treedddbc675ad695d1bae8f32a1c877b47c3a548a09
parent335fb8fc71692830aca0a5a5fe7f60016ee0d0aa
x86_64: Zero extend all registers after ptrace in 32bit entry path.

Strictly it's only needed for eax.

It actually does a little more than strictly needed -- the other registers
are already zero extended.

Also remove the now unnecessary and non functional compat task check
in ptrace.

This is CVE-2007-4573

Found by Wojciech Purczynski

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/x86_64/ia32/ia32entry.S
arch/x86_64/kernel/ptrace.c