| /* Make sure longjmp fortification catches bad signal stacks. |
| Copyright (C) 2013-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <setjmp.h> |
| #include <signal.h> |
| #include <string.h> |
| |
| static int do_test (void); |
| #define TEST_FUNCTION do_test () |
| #include "../test-skeleton.c" |
| |
| static char buf[SIGSTKSZ * 4]; |
| static jmp_buf jb; |
| |
| static void |
| handler (int sig) |
| { |
| if (sig == SIGUSR1) |
| { |
| if (setjmp (jb) != 0) |
| { |
| puts ("setjmp should not have been called"); |
| kill (getpid (), SIGTERM); |
| } |
| } |
| else if (sig == SIGABRT) |
| { |
| /* Yeah it worked. */ |
| _exit (0); |
| } |
| } |
| |
| static int |
| do_test (void) |
| { |
| stack_t ss; |
| |
| set_fortify_handler (handler); |
| |
| /* Create a valid signal stack and enable it. */ |
| ss.ss_sp = buf; |
| ss.ss_size = sizeof (buf); |
| ss.ss_flags = 0; |
| if (sigaltstack (&ss, NULL) < 0) |
| { |
| printf ("first sigaltstack failed: %m\n"); |
| return 1; |
| } |
| |
| /* Trigger the signal handler which will create a jmpbuf that points to the |
| end of the signal stack. */ |
| signal (SIGUSR1, handler); |
| kill (getpid (), SIGUSR1); |
| |
| /* Shrink the signal stack so the jmpbuf is now invalid. |
| We adjust the start & end to handle stacks that grow up & down. */ |
| ss.ss_sp = buf + sizeof (buf) / 2; |
| ss.ss_size = sizeof (buf) / 4; |
| if (sigaltstack (&ss, NULL) < 0) |
| { |
| printf ("second sigaltstack failed: %m\n"); |
| return 1; |
| } |
| |
| /* This should fail. */ |
| longjmp (jb, 1); |
| |
| puts ("longjmp returned and shouldn't"); |
| return 1; |
| } |