[PATCH] slab: remove kmem_cache_t
[linux-2.6.git] / kernel / seccomp.c
1 /*
2  * linux/kernel/seccomp.c
3  *
4  * Copyright 2004-2005  Andrea Arcangeli <andrea@cpushare.com>
5  *
6  * This defines a simple but solid secure-computing mode.
7  */
8
9 #include <linux/seccomp.h>
10 #include <linux/sched.h>
11
12 /* #define SECCOMP_DEBUG 1 */
13
14 /*
15  * Secure computing mode 1 allows only read/write/exit/sigreturn.
16  * To be fully secure this must be combined with rlimit
17  * to limit the stack allocations too.
18  */
19 static int mode1_syscalls[] = {
20         __NR_seccomp_read, __NR_seccomp_write, __NR_seccomp_exit, __NR_seccomp_sigreturn,
21         0, /* null terminated */
22 };
23
24 #ifdef TIF_32BIT
25 static int mode1_syscalls_32[] = {
26         __NR_seccomp_read_32, __NR_seccomp_write_32, __NR_seccomp_exit_32, __NR_seccomp_sigreturn_32,
27         0, /* null terminated */
28 };
29 #endif
30
31 void __secure_computing(int this_syscall)
32 {
33         int mode = current->seccomp.mode;
34         int * syscall;
35
36         switch (mode) {
37         case 1:
38                 syscall = mode1_syscalls;
39 #ifdef TIF_32BIT
40                 if (test_thread_flag(TIF_32BIT))
41                         syscall = mode1_syscalls_32;
42 #endif
43                 do {
44                         if (*syscall == this_syscall)
45                                 return;
46                 } while (*++syscall);
47                 break;
48         default:
49                 BUG();
50         }
51
52 #ifdef SECCOMP_DEBUG
53         dump_stack();
54 #endif
55         do_exit(SIGKILL);
56 }