/* $NetBSD: linux_uselib.c,v 1.27 2008/04/28 20:23:44 martin Exp $ */ /*- * Copyright (c) 1995, 1998 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Christos Zoulas, Frank van der Linden and Eric Haszlakiewicz. * * 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. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ #include <sys/cdefs.h> __KERNEL_RCSID(0, "$NetBSD: linux_uselib.c,v 1.27 2008/04/28 20:23:44 martin Exp $"); #include <sys/param.h> #include <sys/systm.h> #include <sys/kernel.h> #include <sys/proc.h> #include <sys/malloc.h> #include <sys/namei.h> #include <sys/vnode.h> #include <sys/mount.h> #include <sys/exec.h> #include <sys/exec_elf.h> #include <sys/mman.h> #include <sys/syscallargs.h> #include <sys/cpu.h> #include <machine/reg.h> #include <compat/linux/common/linux_types.h> #include <compat/linux/common/linux_signal.h> #include <compat/linux/common/linux_util.h> #include <compat/linux/common/linux_exec.h> #include <compat/linux/common/linux_machdep.h> #include <compat/linux/common/linux_ipc.h> #include <compat/linux/common/linux_sem.h> #ifndef EXEC_AOUT /* define EXEC_AOUT to get prototype from linux_syscall.h */ #define EXEC_AOUT #endif #include <compat/linux/linux_syscallargs.h> #include <compat/linux/linux_syscall.h> /* * The Linux system call to load shared libraries, a.out version. The * a.out shared libs are just files that are mapped onto a fixed * address in the process' address space. The address is given in * a_entry. Read in the header, set up some VM commands and run them. * * Yes, both text and data are mapped at once, so we're left with * writable text for the shared libs. The Linux crt0 seemed to break * sometimes when data was mapped separately. It munmapped a uselib() * of ld.so by hand, which failed with shared text and data for ld.so * Yuck. * * Because of the problem with ZMAGIC executables (text starts * at 0x400 in the file, but needs to be mapped at 0), ZMAGIC * shared libs are not handled very efficiently :-( */ int linux_sys_uselib(struct lwp *l, const struct linux_sys_uselib_args *uap, register_t *retval) { /* { syscallarg(const char *) path; } */ long bsize, dsize, tsize, taddr, baddr, daddr; struct nameidata ni; struct vnode *vp; struct exec hdr; struct exec_vmcmd_set vcset; int i, magic, error; size_t rem; NDINIT(&ni, LOOKUP, FOLLOW | TRYEMULROOT, UIO_USERSPACE, SCARG(uap, path)); if ((error = namei(&ni))) return error; vp = ni.ni_vp; if ((error = vn_rdwr(UIO_READ, vp, (void *) &hdr, LINUX_AOUT_HDR_SIZE, 0, UIO_SYSSPACE, IO_NODELOCKED, l->l_cred, &rem, NULL))) { vrele(vp); return error; } if (rem != 0) { vrele(vp); return ENOEXEC; } if (LINUX_N_MACHTYPE(&hdr) != LINUX_MID_MACHINE) return ENOEXEC; magic = LINUX_N_MAGIC(&hdr); taddr = hdr.a_entry & (~(PAGE_SIZE - 1)); tsize = hdr.a_text; daddr = taddr + tsize; dsize = hdr.a_data + hdr.a_bss; error = vn_marktext(vp); if (error) return (error); vcset.evs_cnt = 0; vcset.evs_used = 0; NEW_VMCMD(&vcset, magic == ZMAGIC ? vmcmd_map_readvn : vmcmd_map_pagedvn, hdr.a_text + hdr.a_data, taddr, vp, LINUX_N_TXTOFF(hdr, magic), VM_PROT_READ|VM_PROT_EXECUTE|VM_PROT_WRITE); baddr = roundup(daddr + hdr.a_data, PAGE_SIZE); bsize = daddr + dsize - baddr; if (bsize > 0) { NEW_VMCMD(&vcset, vmcmd_map_zero, bsize, baddr, NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); } for (i = 0; i < vcset.evs_used && !error; i++) { struct exec_vmcmd *vcp; vcp = &vcset.evs_cmds[i]; error = (*vcp->ev_proc)(l, vcp); } kill_vmcmds(&vcset); vrele(vp); return error; }