linux_uselib.c revision 1.27.2.1
1 /* $NetBSD: linux_uselib.c,v 1.27.2.1 2008/05/10 23:48:56 wrstuden Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas, Frank van der Linden and Eric Haszlakiewicz. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: linux_uselib.c,v 1.27.2.1 2008/05/10 23:48:56 wrstuden Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/proc.h> 39 #include <sys/malloc.h> 40 #include <sys/namei.h> 41 #include <sys/vnode.h> 42 #include <sys/mount.h> 43 #include <sys/exec.h> 44 #include <sys/exec_elf.h> 45 46 #include <sys/mman.h> 47 #include <sys/sa.h> 48 #include <sys/syscallargs.h> 49 50 #include <sys/cpu.h> 51 #include <machine/reg.h> 52 53 #include <compat/linux/common/linux_types.h> 54 #include <compat/linux/common/linux_signal.h> 55 #include <compat/linux/common/linux_util.h> 56 #include <compat/linux/common/linux_exec.h> 57 #include <compat/linux/common/linux_machdep.h> 58 #include <compat/linux/common/linux_ipc.h> 59 #include <compat/linux/common/linux_sem.h> 60 61 #ifndef EXEC_AOUT 62 /* define EXEC_AOUT to get prototype from linux_syscall.h */ 63 #define EXEC_AOUT 64 #endif 65 66 #include <compat/linux/linux_syscallargs.h> 67 #include <compat/linux/linux_syscall.h> 68 69 /* 70 * The Linux system call to load shared libraries, a.out version. The 71 * a.out shared libs are just files that are mapped onto a fixed 72 * address in the process' address space. The address is given in 73 * a_entry. Read in the header, set up some VM commands and run them. 74 * 75 * Yes, both text and data are mapped at once, so we're left with 76 * writable text for the shared libs. The Linux crt0 seemed to break 77 * sometimes when data was mapped separately. It munmapped a uselib() 78 * of ld.so by hand, which failed with shared text and data for ld.so 79 * Yuck. 80 * 81 * Because of the problem with ZMAGIC executables (text starts 82 * at 0x400 in the file, but needs to be mapped at 0), ZMAGIC 83 * shared libs are not handled very efficiently :-( 84 */ 85 86 int 87 linux_sys_uselib(struct lwp *l, const struct linux_sys_uselib_args *uap, register_t *retval) 88 { 89 /* { 90 syscallarg(const char *) path; 91 } */ 92 long bsize, dsize, tsize, taddr, baddr, daddr; 93 struct nameidata ni; 94 struct vnode *vp; 95 struct exec hdr; 96 struct exec_vmcmd_set vcset; 97 int i, magic, error; 98 size_t rem; 99 100 NDINIT(&ni, LOOKUP, FOLLOW | TRYEMULROOT, UIO_USERSPACE, 101 SCARG(uap, path)); 102 103 if ((error = namei(&ni))) 104 return error; 105 106 vp = ni.ni_vp; 107 108 if ((error = vn_rdwr(UIO_READ, vp, (void *) &hdr, LINUX_AOUT_HDR_SIZE, 109 0, UIO_SYSSPACE, IO_NODELOCKED, l->l_cred, 110 &rem, NULL))) { 111 vrele(vp); 112 return error; 113 } 114 115 if (rem != 0) { 116 vrele(vp); 117 return ENOEXEC; 118 } 119 120 if (LINUX_N_MACHTYPE(&hdr) != LINUX_MID_MACHINE) 121 return ENOEXEC; 122 123 magic = LINUX_N_MAGIC(&hdr); 124 taddr = hdr.a_entry & (~(PAGE_SIZE - 1)); 125 tsize = hdr.a_text; 126 daddr = taddr + tsize; 127 dsize = hdr.a_data + hdr.a_bss; 128 129 error = vn_marktext(vp); 130 if (error) 131 return (error); 132 133 vcset.evs_cnt = 0; 134 vcset.evs_used = 0; 135 136 NEW_VMCMD(&vcset, 137 magic == ZMAGIC ? vmcmd_map_readvn : vmcmd_map_pagedvn, 138 hdr.a_text + hdr.a_data, taddr, 139 vp, LINUX_N_TXTOFF(hdr, magic), 140 VM_PROT_READ|VM_PROT_EXECUTE|VM_PROT_WRITE); 141 142 baddr = roundup(daddr + hdr.a_data, PAGE_SIZE); 143 bsize = daddr + dsize - baddr; 144 if (bsize > 0) { 145 NEW_VMCMD(&vcset, vmcmd_map_zero, bsize, baddr, 146 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 147 } 148 149 for (i = 0; i < vcset.evs_used && !error; i++) { 150 struct exec_vmcmd *vcp; 151 152 vcp = &vcset.evs_cmds[i]; 153 error = (*vcp->ev_proc)(l, vcp); 154 } 155 156 kill_vmcmds(&vcset); 157 158 vrele(vp); 159 160 return error; 161 } 162
Indexes created Tue Sep 23 01:09:51 GMT 2025