| /* Copyright (C) 2011-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011. |
| |
| 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 <jmpbuf-offsets.h> |
| #include <sysdep.h> |
| #include <setjmp.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stackinfo.h> |
| |
| #ifdef _STACK_GROWS_DOWN |
| #define called_from(this, saved) ((this) < (saved)) |
| #else |
| #define called_from(this, saved) ((this) > (saved)) |
| #endif |
| |
| extern void ____longjmp_chk (__jmp_buf __env, int __val) |
| __attribute__ ((__noreturn__)); |
| |
| void ____longjmp_chk (__jmp_buf env, int val) |
| { |
| void *this_frame = __builtin_frame_address (0); |
| void *saved_frame = JB_FRAME_ADDRESS (env); |
| INTERNAL_SYSCALL_DECL (err); |
| stack_t ss; |
| |
| /* If "env" is from a frame that called us, we're all set. */ |
| if (called_from(this_frame, saved_frame)) |
| __longjmp (env, val); |
| |
| /* If we can't get the current stack state, give up and do the longjmp. */ |
| if (INTERNAL_SYSCALL (sigaltstack, err, 2, NULL, &ss) != 0) |
| __longjmp (env, val); |
| |
| /* If we we are executing on the alternate stack and within the |
| bounds, do the longjmp. */ |
| if (ss.ss_flags == SS_ONSTACK && |
| (this_frame >= ss.ss_sp && this_frame < (ss.ss_sp + ss.ss_size))) |
| __longjmp (env, val); |
| |
| __fortify_fail ("longjmp causes uninitialized stack frame"); |
| } |