linux/arch/m68k/include
Andreas Schwab 8474ba7419 m68k: Define asmlinkage_protect
Make sure the compiler does not modify arguments of syscall functions.
This can happen if the compiler generates a tailcall to another
function.  For example, without asmlinkage_protect sys_openat is compiled
into this function:

sys_openat:
	clr.l %d0
	move.w 18(%sp),%d0
	move.l %d0,16(%sp)
	jbra do_sys_open

Note how the fourth argument is modified in place, modifying the register
%d4 that gets restored from this stack slot when the function returns to
user-space.  The caller may expect the register to be unmodified across
system calls.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: stable@vger.kernel.org
2015-09-28 09:59:45 +02:00
..
asm m68k: Define asmlinkage_protect 2015-09-28 09:59:45 +02:00
uapi/asm m68k: Wire up membarrier 2015-09-28 09:59:44 +02:00