1 /* $NetBSD: linux_exec_machdep.c,v 1.18 2010/07/07 01:30:33 chs Exp $ */ 2 3 /*- 4 * Copyright (c) 2005 Emmanuel Dreyfus, all rights reserved 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Emmanuel Dreyfus 17 * 4. The name of the author may not be used to endorse or promote 18 * products derived from this software without specific prior written 19 * permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS'' 22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 23 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: linux_exec_machdep.c,v 1.18 2010/07/07 01:30:33 chs Exp $"); 36 37 #define ELFSIZE 64 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/kernel.h> 42 #include <sys/resource.h> 43 #include <sys/proc.h> 44 #include <sys/conf.h> 45 #include <sys/malloc.h> 46 #include <sys/exec_elf.h> 47 #include <sys/vnode.h> 48 #include <sys/lwp.h> 49 #include <sys/exec.h> 50 #include <sys/stat.h> 51 #include <sys/kauth.h> 52 53 #include <sys/cpu.h> 54 #include <machine/vmparam.h> 55 #include <sys/syscallargs.h> 56 57 #include <uvm/uvm.h> 58 59 #include <compat/linux/common/linux_types.h> 60 #include <compat/linux/common/linux_signal.h> 61 #include <compat/linux/common/linux_machdep.h> 62 #include <compat/linux/common/linux_util.h> 63 #include <compat/linux/common/linux_ioctl.h> 64 #include <compat/linux/common/linux_hdio.h> 65 #include <compat/linux/common/linux_exec.h> 66 #include <compat/linux/common/linux_errno.h> 67 #include <compat/linux/common/linux_prctl.h> 68 #include <compat/linux/common/linux_ipc.h> 69 #include <compat/linux/common/linux_sem.h> 70 #include <compat/linux/linux_syscallargs.h> 71 72 int 73 linux_exec_setup_stack(struct lwp *l, struct exec_package *epp) 74 { 75 u_long max_stack_size; 76 u_long access_linear_min, access_size; 77 u_long noaccess_linear_min, noaccess_size; 78 79 #ifndef USRSTACK32 80 #define USRSTACK32 (0x00000000ffffffffL & ~PGOFSET) 81 #endif 82 83 if (epp->ep_flags & EXEC_32) { 84 epp->ep_minsaddr = USRSTACK32; 85 max_stack_size = MAXSSIZ; 86 if (epp->ep_minsaddr > LINUX_USRSTACK32) 87 epp->ep_minsaddr = LINUX_USRSTACK32; 88 } else { 89 epp->ep_minsaddr = USRSTACK; 90 max_stack_size = MAXSSIZ; 91 if (epp->ep_minsaddr > LINUX_USRSTACK) 92 epp->ep_minsaddr = LINUX_USRSTACK; 93 94 } 95 96 epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr, 97 max_stack_size); 98 epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur; 99 100 /* 101 * set up commands for stack. note that this takes *two*, one to 102 * map the part of the stack which we can access, and one to map 103 * the part which we can't. 104 * 105 * arguably, it could be made into one, but that would require the 106 * addition of another mapping proc, which is unnecessary 107 */ 108 access_size = epp->ep_ssize; 109 access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size); 110 noaccess_size = max_stack_size - access_size; 111 noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 112 access_size), noaccess_size); 113 if (noaccess_size > 0) { 114 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size, 115 noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK); 116 } 117 KASSERT(access_size > 0); 118 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size, 119 access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE, 120 VMCMD_STACK); 121 122 return 0; 123 } 124 125 int 126 ELFNAME2(linux,copyargs)(struct lwp *l, struct exec_package *pack, 127 struct ps_strings *arginfo, char **stackp, void *argp) 128 { 129 struct linux_extra_stack_data64 *esdp, esd; 130 struct elf_args *ap; 131 struct vattr *vap; 132 Elf_Ehdr *eh; 133 Elf_Phdr *ph; 134 u_long phsize; 135 Elf_Addr phdr = 0; 136 int error; 137 int i; 138 139 if ((error = copyargs(l, pack, arginfo, stackp, argp)) != 0) 140 return error; 141 142 /* 143 * Push extra arguments on the stack needed by dynamically 144 * linked binaries and static binaries as well. 145 */ 146 memset(&esd, 0, sizeof(esd)); 147 esdp = (struct linux_extra_stack_data64 *)(*stackp); 148 ap = (struct elf_args *)pack->ep_emul_arg; 149 vap = pack->ep_vap; 150 eh = (Elf_Ehdr *)pack->ep_hdr; 151 152 /* 153 * We forgot this, so we need to reload it now. XXX keep track of it? 154 */ 155 if (ap == NULL) { 156 phsize = eh->e_phnum * sizeof(Elf_Phdr); 157 ph = (Elf_Phdr *)malloc(phsize, M_TEMP, M_WAITOK); 158 error = exec_read_from(l, pack->ep_vp, eh->e_phoff, ph, phsize); 159 if (error != 0) { 160 for (i = 0; i < eh->e_phnum; i++) { 161 if (ph[i].p_type == PT_PHDR) { 162 phdr = ph[i].p_vaddr; 163 break; 164 } 165 } 166 } 167 free(ph, M_TEMP); 168 } 169 170 171 /* 172 * The exec_package doesn't have a proc pointer and it's not 173 * exactly trivial to add one since the credentials are 174 * changing. XXX Linux uses curlwp's credentials. 175 * Why can't we use them too? 176 */ 177 178 i = 0; 179 esd.ai[i].a_type = LINUX_AT_HWCAP; 180 esd.ai[i++].a_v = rcr4(); 181 182 esd.ai[i].a_type = AT_PAGESZ; 183 esd.ai[i++].a_v = PAGE_SIZE; 184 185 esd.ai[i].a_type = LINUX_AT_CLKTCK; 186 esd.ai[i++].a_v = hz; 187 188 esd.ai[i].a_type = AT_PHDR; 189 esd.ai[i++].a_v = (ap ? ap->arg_phaddr: phdr); 190 191 esd.ai[i].a_type = AT_PHENT; 192 esd.ai[i++].a_v = (ap ? ap->arg_phentsize : eh->e_phentsize); 193 194 esd.ai[i].a_type = AT_PHNUM; 195 esd.ai[i++].a_v = (ap ? ap->arg_phnum : eh->e_phnum); 196 197 esd.ai[i].a_type = AT_BASE; 198 esd.ai[i++].a_v = (ap ? ap->arg_interp : 0); 199 200 esd.ai[i].a_type = AT_FLAGS; 201 esd.ai[i++].a_v = 0; 202 203 esd.ai[i].a_type = AT_ENTRY; 204 esd.ai[i++].a_v = (ap ? ap->arg_entry : eh->e_entry); 205 206 esd.ai[i].a_type = LINUX_AT_EGID; 207 esd.ai[i++].a_v = ((vap->va_mode & S_ISGID) ? 208 vap->va_gid : kauth_cred_getegid(l->l_cred)); 209 210 esd.ai[i].a_type = LINUX_AT_GID; 211 esd.ai[i++].a_v = kauth_cred_getgid(l->l_cred); 212 213 esd.ai[i].a_type = LINUX_AT_EUID; 214 esd.ai[i++].a_v = ((vap->va_mode & S_ISUID) ? 215 vap->va_uid : kauth_cred_geteuid(l->l_cred)); 216 217 esd.ai[i].a_type = LINUX_AT_UID; 218 esd.ai[i++].a_v = kauth_cred_getuid(l->l_cred); 219 220 esd.ai[i].a_type = LINUX_AT_SECURE; 221 esd.ai[i++].a_v = 0; 222 223 esd.ai[i].a_type = LINUX_AT_PLATFORM; 224 esd.ai[i++].a_v = (Elf_Addr)&esdp->hw_platform[0]; 225 226 esd.ai[i].a_type = AT_NULL; 227 esd.ai[i++].a_v = 0; 228 229 #ifdef DEBUG_LINUX 230 if (i != LINUX_ELF_AUX_ENTRIES) { 231 printf("linux_elf64_copyargs: %d Aux entries\n", i); 232 return EINVAL; 233 } 234 #endif 235 236 strcpy(esd.hw_platform, LINUX_PLATFORM); 237 238 if (ap) { 239 free((char *)ap, M_TEMP); 240 pack->ep_emul_arg = NULL; 241 } 242 243 /* 244 * Copy out the ELF auxiliary table and hw platform name 245 */ 246 if ((error = copyout(&esd, esdp, sizeof(esd))) != 0) 247 return error; 248 *stackp += sizeof(esd); 249 250 return 0; 251 } 252