freebsd-nq/lib/libc/amd64/gen/setjmp.S
Konstantin Belousov bd6060a1c6 Switch libc from using _sig{procmask,action,suspend} symbols, which
are aliases for the syscall stubs and are plt-interposed, to the
libc-private aliases of internally interposed sigprocmask() etc.

Since e.g. _sigaction is not interposed by libthr, calling signal()
removes thr_sighandler() from the handler slot etc.  The result was
breaking signal semantic and rtld locking.

The added __libc_sigprocmask and other symbols are hidden, they are
not exported and cannot be called through PLT.  The setjmp/longjmp
functions for x86 were changed to use direct calls, and since
PIC_PROLOGUE only needed for functional PLT indirection on i386, it is
removed as well.

The PowerPC bug of calling the syscall directly in the setjmp/longjmp
implementation is kept as is.

Reported by:	Pete French <petefrench@ingresso.co.uk>
Tested by:	Michiel Boland <boland37@xs4all.nl>
Reviewed by:	jilles (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-08-29 14:25:01 +00:00

117 lines
3.6 KiB
ArmAsm

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
.asciz "@(#)setjmp.s 5.1 (Berkeley) 4/23/90"
#endif /* LIBC_SCCS and not lint */
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
/*
* C library -- _setjmp, _longjmp
*
* longjmp(a,v)
* will generate a "return(v)" from the last call to
* setjmp(a)
* by restoring registers from the environment 'a'.
* The previous signal state is restored.
*/
#include "SYS.h"
ENTRY(setjmp)
pushq %rdi
movq %rdi,%rcx
movq $1,%rdi /* SIG_BLOCK */
movq $0,%rsi /* (sigset_t*)set */
leaq 72(%rcx),%rdx /* 9,10; (sigset_t*)oset */
/* stack is 16-byte aligned */
call __libc_sigprocmask
popq %rdi
movq %rdi,%rcx
movq 0(%rsp),%rdx /* retval */
movq %rdx, 0(%rcx) /* 0; retval */
movq %rbx, 8(%rcx) /* 1; rbx */
movq %rsp,16(%rcx) /* 2; rsp */
movq %rbp,24(%rcx) /* 3; rbp */
movq %r12,32(%rcx) /* 4; r12 */
movq %r13,40(%rcx) /* 5; r13 */
movq %r14,48(%rcx) /* 6; r14 */
movq %r15,56(%rcx) /* 7; r15 */
fnstcw 64(%rcx) /* 8; fpu cw */
stmxcsr 68(%rcx) /* and mxcsr */
xorq %rax,%rax
ret
END(setjmp)
WEAK_REFERENCE(__longjmp, longjmp)
ENTRY(__longjmp)
pushq %rdi
pushq %rsi
movq %rdi,%rdx
movq $3,%rdi /* SIG_SETMASK */
leaq 72(%rdx),%rsi /* (sigset_t*)set */
movq $0,%rdx /* (sigset_t*)oset */
subq $0x8,%rsp /* make the stack 16-byte aligned */
call __libc_sigprocmask
addq $0x8,%rsp
popq %rsi
popq %rdi /* jmpbuf */
movq %rdi,%rdx
/* Restore the mxcsr, but leave exception flags intact. */
stmxcsr -4(%rsp)
movl 68(%rdx),%eax
andl $0xffffffc0,%eax
movl -4(%rsp),%edi
andl $0x3f,%edi
xorl %eax,%edi
movl %edi,-4(%rsp)
ldmxcsr -4(%rsp)
movq %rsi,%rax /* retval */
movq 0(%rdx),%rcx
movq 8(%rdx),%rbx
movq 16(%rdx),%rsp
movq 24(%rdx),%rbp
movq 32(%rdx),%r12
movq 40(%rdx),%r13
movq 48(%rdx),%r14
movq 56(%rdx),%r15
fldcw 64(%rdx)
testq %rax,%rax
jnz 1f
incq %rax
1: movq %rcx,0(%rsp)
ret
END(__longjmp)
.section .note.GNU-stack,"",%progbits