move seccomp from /proc to a prctl

This reduces the memory footprint and it enforces that only the current
task can enable seccomp on itself (this is a requirement for a
strightforward [modulo preempt ;) ] TIF_NOTSC implementation).

Signed-off-by: Andrea Arcangeli <andrea@cpushare.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index ed92e2f03342..4d141ae3e802 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -31,6 +31,7 @@
 #include <linux/cn_proc.h>
 #include <linux/getcpu.h>
 #include <linux/task_io_accounting_ops.h>
+#include <linux/seccomp.h>
 
 #include <linux/compat.h>
 #include <linux/syscalls.h>
@@ -2242,6 +2243,13 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
                         error = SET_ENDIAN(current, arg2);
                         break;
 
+                case PR_GET_SECCOMP:
+                        error = prctl_get_seccomp();
+                        break;
+                case PR_SET_SECCOMP:
+                        error = prctl_set_seccomp(arg2);
+                        break;
+
                 default:
                         error = -EINVAL;
                         break;