From da0331a873dbb62462c151c3d824da2f6fe2e770 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Tue, 22 May 2012 12:43:46 -0700 Subject: Add x32 arch_prctl --- sysdeps/unix/sysv/linux/x86_64/x32/Makefile | 4 ++ sysdeps/unix/sysv/linux/x86_64/x32/arch_prctl.c | 62 +++++++++++++++++++++++++ 2 files changed, 66 insertions(+) create mode 100644 sysdeps/unix/sysv/linux/x86_64/x32/arch_prctl.c (limited to 'sysdeps') diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile index 5f77df7c7a..aa78238a0d 100644 --- a/sysdeps/unix/sysv/linux/x86_64/x32/Makefile +++ b/sysdeps/unix/sysv/linux/x86_64/x32/Makefile @@ -1,3 +1,7 @@ +ifeq ($(subdir),misc) +sysdep_routines += arch_prctl +endif + ifeq ($(subdir),posix) sysdep_routines += getcpu sched_getcpu-static endif diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/arch_prctl.c b/sysdeps/unix/sysv/linux/x86_64/x32/arch_prctl.c new file mode 100644 index 0000000000..6933306de9 --- /dev/null +++ b/sysdeps/unix/sysv/linux/x86_64/x32/arch_prctl.c @@ -0,0 +1,62 @@ +/* arch_prctl call for Linux/x32. + Copyright (C) 2012 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 + . */ + +#include +#include +#include +#include + +/* Since x32 arch_prctl stores 32-bit base address of segment registers + %fs and %gs as unsigned 64-bit value via ARCH_GET_FS and ARCH_GET_GS, + we use an unsigned 64-bit variable to hold the base address and copy + it to ADDR after the system call returns. */ + +int +__arch_prctl (int code, uintptr_t *addr) +{ + int res; + uint64_t addr64; + void *prctl_arg = addr; + + switch (code) + { + case ARCH_GET_FS: + case ARCH_GET_GS: + prctl_arg = &addr64; + break; + } + + res = INLINE_SYSCALL (arch_prctl, 2, code, prctl_arg); + if (res == 0) + switch (code) + { + case ARCH_GET_FS: + case ARCH_GET_GS: + /* Check for a large value that overflows. */ + if ((uintptr_t) addr64 != addr64) + { + __set_errno (EOVERFLOW); + return -1; + } + *addr = (uintptr_t) addr64; + break; + } + + return res; +} +weak_alias (__arch_prctl, arch_prctl) -- cgit 1.4.1