/* $NetBSD: linux_exec_machdep.c,v 1.24 2020/09/05 16:30:10 riastradh Exp $ */ /*- * Copyright (c) 2005 Emmanuel Dreyfus, all rights reserved * * 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Emmanuel Dreyfus * 4. The name of the author may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR 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 AUTHOR 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 __KERNEL_RCSID(0, "$NetBSD: linux_exec_machdep.c,v 1.24 2020/09/05 16:30:10 riastradh Exp $"); #define ELFSIZE 64 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include int linux_exec_setup_stack(struct lwp *l, struct exec_package *epp) { u_long max_stack_size; u_long access_linear_min, access_size; u_long noaccess_linear_min, noaccess_size; #ifndef USRSTACK32 #define USRSTACK32 (0x00000000ffffffffL & ~PGOFSET) #endif if (epp->ep_flags & EXEC_32) { epp->ep_minsaddr = USRSTACK32; max_stack_size = MAXSSIZ; if (epp->ep_minsaddr > LINUX_USRSTACK32) epp->ep_minsaddr = LINUX_USRSTACK32; } else { epp->ep_minsaddr = USRSTACK; max_stack_size = MAXSSIZ; if (epp->ep_minsaddr > LINUX_USRSTACK) epp->ep_minsaddr = LINUX_USRSTACK; } epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr, max_stack_size); epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur; /* * set up commands for stack. note that this takes *two*, one to * map the part of the stack which we can access, and one to map * the part which we can't. * * arguably, it could be made into one, but that would require the * addition of another mapping proc, which is unnecessary */ access_size = epp->ep_ssize; access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size); noaccess_size = max_stack_size - access_size; noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, access_size), noaccess_size); if (noaccess_size > 0) { NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size, noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK); } KASSERT(access_size > 0); NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size, access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE, VMCMD_STACK); return 0; } int ELFNAME2(linux,copyargs)(struct lwp *l, struct exec_package *pack, struct ps_strings *arginfo, char **stackp, void *argp) { struct linux_extra_stack_data64 *esdp, esd; struct elf_args *ap; struct vattr *vap; Elf_Ehdr *eh; Elf_Phdr *ph; u_long phsize; Elf_Addr phdr = 0; int error; int i; if ((error = copyargs(l, pack, arginfo, stackp, argp)) != 0) return error; /* * Push extra arguments on the stack needed by dynamically * linked binaries and static binaries as well. */ memset(&esd, 0, sizeof(esd)); esdp = (struct linux_extra_stack_data64 *)(*stackp); ap = (struct elf_args *)pack->ep_emul_arg; vap = pack->ep_vap; eh = (Elf_Ehdr *)pack->ep_hdr; /* * We forgot this, so we need to reload it now. XXX keep track of it? */ if (ap == NULL) { phsize = eh->e_phnum * sizeof(Elf_Phdr); ph = (Elf_Phdr *)kmem_alloc(phsize, KM_SLEEP); error = exec_read(l, pack->ep_vp, eh->e_phoff, ph, phsize, 0); if (error != 0) { for (i = 0; i < eh->e_phnum; i++) { if (ph[i].p_type == PT_PHDR) { phdr = ph[i].p_vaddr; break; } } } kmem_free(ph, phsize); } /* * The exec_package doesn't have a proc pointer and it's not * exactly trivial to add one since the credentials are * changing. XXX Linux uses curlwp's credentials. * Why can't we use them too? */ i = 0; esd.ai[i].a_type = LINUX_AT_HWCAP; esd.ai[i++].a_v = rcr4(); esd.ai[i].a_type = AT_PAGESZ; esd.ai[i++].a_v = PAGE_SIZE; esd.ai[i].a_type = LINUX_AT_CLKTCK; esd.ai[i++].a_v = hz; esd.ai[i].a_type = AT_PHDR; esd.ai[i++].a_v = (ap ? ap->arg_phaddr: phdr); esd.ai[i].a_type = AT_PHENT; esd.ai[i++].a_v = (ap ? ap->arg_phentsize : eh->e_phentsize); esd.ai[i].a_type = AT_PHNUM; esd.ai[i++].a_v = (ap ? ap->arg_phnum : eh->e_phnum); esd.ai[i].a_type = AT_BASE; esd.ai[i++].a_v = (ap ? ap->arg_interp : 0); esd.ai[i].a_type = AT_FLAGS; esd.ai[i++].a_v = 0; esd.ai[i].a_type = AT_ENTRY; esd.ai[i++].a_v = (ap ? ap->arg_entry : eh->e_entry); esd.ai[i].a_type = LINUX_AT_EGID; esd.ai[i++].a_v = ((vap->va_mode & S_ISGID) ? vap->va_gid : kauth_cred_getegid(l->l_cred)); esd.ai[i].a_type = LINUX_AT_GID; esd.ai[i++].a_v = kauth_cred_getgid(l->l_cred); esd.ai[i].a_type = LINUX_AT_EUID; esd.ai[i++].a_v = ((vap->va_mode & S_ISUID) ? vap->va_uid : kauth_cred_geteuid(l->l_cred)); esd.ai[i].a_type = LINUX_AT_UID; esd.ai[i++].a_v = kauth_cred_getuid(l->l_cred); esd.ai[i].a_type = LINUX_AT_SECURE; esd.ai[i++].a_v = 0; esd.ai[i].a_type = LINUX_AT_PLATFORM; esd.ai[i++].a_v = (Elf_Addr)&esdp->hw_platform[0]; esd.ai[i].a_type = LINUX_AT_RANDOM; esd.ai[i++].a_v = (Elf_Addr)&esdp->randbytes[0]; esd.randbytes[0] = cprng_strong32(); esd.randbytes[1] = cprng_strong32(); esd.randbytes[2] = cprng_strong32(); esd.randbytes[3] = cprng_strong32(); esd.ai[i].a_type = AT_NULL; esd.ai[i++].a_v = 0; KASSERT(i == LINUX_ELF_AUX_ENTRIES); strcpy(esd.hw_platform, LINUX_PLATFORM); exec_free_emul_arg(pack); /* * Copy out the ELF auxiliary table and hw platform name */ if ((error = copyout(&esd, esdp, sizeof(esd))) != 0) return error; *stackp += sizeof(esd); return 0; }