1 /* Copyright (C) 2011-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library. If not, see
16 <https://www.gnu.org/licenses/>. */
18 #include <jmpbuf-offsets.h>
23 #include <stackinfo.h>
25 #ifdef _STACK_GROWS_DOWN
26 #define called_from(this, saved) ((this) < (saved))
28 #define called_from(this, saved) ((this) > (saved))
31 extern void ____longjmp_chk (__jmp_buf __env
, int __val
)
32 __attribute__ ((__noreturn__
));
34 void ____longjmp_chk (__jmp_buf env
, int val
)
36 void *this_frame
= __builtin_frame_address (0);
37 void *saved_frame
= JB_FRAME_ADDRESS (env
);
40 /* If "env" is from a frame that called us, we're all set. */
41 if (called_from(this_frame
, saved_frame
))
44 /* If we can't get the current stack state, give up and do the longjmp. */
45 if (INTERNAL_SYSCALL_CALL (sigaltstack
, NULL
, &ss
) != 0)
48 /* If we we are executing on the alternate stack and within the
49 bounds, do the longjmp. */
50 if (ss
.ss_flags
== SS_ONSTACK
51 && (this_frame
>= ss
.ss_sp
&& this_frame
< (ss
.ss_sp
+ ss
.ss_size
)))
54 __fortify_fail ("longjmp causes uninitialized stack frame");