mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 00:31:08 +00:00
f8e9c4d30c
In makecontext the FDE needs to be terminated before the return
trampoline otherwise backtrace called within a context created by
makecontext yields infinite backtrace.
This bug has been present for a long time, stdlib/tst-makecontext did
not fail until recent commit e535ce25. Tested on mips-linux-gnu and
mips64el-linux-gnuabi64 and mips-linux-gnu, no regression.
This fixes stdlib/tst-makecontext on MIPS.
Changelog:
[BZ #19792]
* sysdeps/unix/sysv/linux/mips/makecontext.S (__makecontext):
Terminate FDE before return label.
199 lines
4.2 KiB
ArmAsm
199 lines
4.2 KiB
ArmAsm
/* Modify saved context.
|
|
Copyright (C) 2009-2016 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Maciej W. Rozycki <macro@codesourcery.com>.
|
|
|
|
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 <sysdep.h>
|
|
#include <sys/asm.h>
|
|
#include <sys/fpregdef.h>
|
|
#include <sys/regdef.h>
|
|
|
|
#include "ucontext_i.h"
|
|
|
|
/* int makecontext (ucontext_t *ucp, (void *func) (), int argc, ...) */
|
|
|
|
.text
|
|
.set nomips16
|
|
LOCALSZ = 0
|
|
ARGSZ = 0
|
|
MASK = 0x00000000
|
|
#ifdef __PIC__
|
|
LOCALSZ = 1 /* save gp */
|
|
#endif
|
|
#if _MIPS_SIM != _ABIO32
|
|
ARGSZ = 5 /* save a3-a7 */
|
|
# ifdef __PIC__
|
|
MASK = 0x10000000
|
|
# endif
|
|
#endif
|
|
FRAMESZ = (((ARGSZ + LOCALSZ) * SZREG) + ALSZ) & ALMASK
|
|
GPOFF = FRAMESZ - ((ARGSZ + 1) * SZREG)
|
|
#if _MIPS_SIM != _ABIO32
|
|
A3OFF = FRAMESZ - (5 * SZREG) /* callee-allocated */
|
|
A4OFF = FRAMESZ - (4 * SZREG)
|
|
A5OFF = FRAMESZ - (3 * SZREG)
|
|
A6OFF = FRAMESZ - (2 * SZREG)
|
|
A7OFF = FRAMESZ - (1 * SZREG)
|
|
NARGREGS = 8
|
|
#else
|
|
A3OFF = FRAMESZ + (3 * SZREG) /* caller-allocated */
|
|
NARGREGS = 4
|
|
#endif
|
|
|
|
NESTED (__makecontext, FRAMESZ, ra)
|
|
.mask MASK, -(ARGSZ * SZREG)
|
|
.fmask 0x00000000, 0
|
|
|
|
98:
|
|
#ifdef __PIC__
|
|
SETUP_GP
|
|
#endif
|
|
|
|
PTR_ADDIU sp, -FRAMESZ
|
|
cfi_adjust_cfa_offset (FRAMESZ)
|
|
|
|
#ifdef __PIC__
|
|
SETUP_GP64_STACK (GPOFF, __makecontext)
|
|
SAVE_GP (GPOFF)
|
|
#endif
|
|
|
|
#ifdef PROF
|
|
.set noat
|
|
move AT, ra
|
|
jal _mcount
|
|
.set at
|
|
#endif
|
|
|
|
/* Store args to be passed. */
|
|
REG_S a3, A3OFF(sp)
|
|
#if _MIPS_SIM != _ABIO32
|
|
REG_S a4, A4OFF(sp)
|
|
REG_S a5, A5OFF(sp)
|
|
REG_S a6, A6OFF(sp)
|
|
REG_S a7, A7OFF(sp)
|
|
#endif
|
|
|
|
/* Store a magic flag. */
|
|
li v1, 1
|
|
REG_S v1, (0 * SZREG + MCONTEXT_GREGS)(a0) /* zero */
|
|
|
|
/* Set up the stack. */
|
|
PTR_L t0, STACK_SP(a0)
|
|
PTR_L t2, STACK_SIZE(a0)
|
|
PTR_ADDIU t1, sp, A3OFF
|
|
PTR_ADDU t0, t2
|
|
and t0, ALMASK
|
|
blez a2, 2f /* no arguments */
|
|
|
|
/* Store register arguments. */
|
|
PTR_ADDIU t2, a0, MCONTEXT_GREGS + 4 * SZREG
|
|
move t3, zero
|
|
0:
|
|
addiu t3, 1
|
|
REG_L v1, (t1)
|
|
PTR_ADDIU t1, SZREG
|
|
REG_S v1, (t2)
|
|
PTR_ADDIU t2, SZREG
|
|
bgeu t3, a2, 2f /* all done */
|
|
bltu t3, NARGREGS, 0b /* next */
|
|
|
|
/* Make room for stack arguments. */
|
|
PTR_SUBU t2, a2, t3
|
|
PTR_SLL t2, 3
|
|
PTR_SUBU t0, t2
|
|
and t0, ALMASK
|
|
|
|
/* Store stack arguments. */
|
|
move t2, t0
|
|
1:
|
|
addiu t3, 1
|
|
REG_L v1, (t1)
|
|
PTR_ADDIU t1, SZREG
|
|
REG_S v1, (t2)
|
|
PTR_ADDIU t2, SZREG
|
|
bltu t3, a2, 1b /* next */
|
|
|
|
2:
|
|
#if _MIPS_SIM == _ABIO32
|
|
/* Make room for a0-a3 storage. */
|
|
PTR_ADDIU t0, -(NARGSAVE * SZREG)
|
|
#endif
|
|
PTR_L v1, UCONTEXT_LINK(a0)
|
|
#ifdef __PIC__
|
|
PTR_ADDIU t9, 99f - 98b
|
|
#else
|
|
PTR_LA t9, 99f
|
|
#endif
|
|
REG_S t0, (29 * SZREG + MCONTEXT_GREGS)(a0) /* sp */
|
|
REG_S v1, (16 * SZREG + MCONTEXT_GREGS)(a0) /* s0 */
|
|
#ifdef __PIC__
|
|
REG_S gp, (17 * SZREG + MCONTEXT_GREGS)(a0) /* s1 */
|
|
#endif
|
|
REG_S t9, (31 * SZREG + MCONTEXT_GREGS)(a0) /* ra */
|
|
REG_S a1, MCONTEXT_PC(a0)
|
|
|
|
#ifdef __PIC__
|
|
RESTORE_GP64_STACK
|
|
PTR_ADDIU sp, FRAMESZ
|
|
cfi_adjust_cfa_offset (-FRAMESZ)
|
|
#endif
|
|
jr ra
|
|
|
|
/* We need to terminate the FDE to stop unwinding if backtrace was
|
|
called within a context created by makecontext. */
|
|
cfi_endproc
|
|
nop
|
|
|
|
99:
|
|
#ifdef __PIC__
|
|
move gp, s1
|
|
#endif
|
|
move a0, zero
|
|
beqz s0, 0f
|
|
|
|
/* setcontext (ucp) */
|
|
move a0, s0
|
|
#ifdef __PIC__
|
|
PTR_LA t9, JUMPTARGET (__setcontext)
|
|
jalr t9
|
|
# if _MIPS_SIM == _ABIO32
|
|
move gp, s1
|
|
# endif
|
|
#else
|
|
jal JUMPTARGET (__setcontext)
|
|
#endif
|
|
move a0, v0
|
|
|
|
0:
|
|
/* exit (a0) */
|
|
#ifdef __PIC__
|
|
PTR_LA t9, HIDDEN_JUMPTARGET (exit)
|
|
jalr t9
|
|
#else
|
|
jal HIDDEN_JUMPTARGET (exit)
|
|
#endif
|
|
|
|
/* You don't exist, you won't feel anything. */
|
|
1:
|
|
lb zero, (zero)
|
|
b 1b
|
|
|
|
cfi_startproc
|
|
PSEUDO_END (__makecontext)
|
|
|
|
weak_alias (__makecontext, makecontext)
|