/* $NetBSD: netbsd32_execve.c,v 1.21 2005/05/19 20:16:19 elad Exp $ */ /* * Copyright (c) 1998, 2001 Matthew R. Green * 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. 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 AUTHOR ``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 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: netbsd32_execve.c,v 1.21 2005/05/19 20:16:19 elad Exp $"); #if defined(_KERNEL_OPT) #include "opt_ktrace.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* this is provided by kern/kern_exec.c */ extern u_int exec_maxhdrsz; #if defined(LKM) || defined(_LKM) extern struct lock exec_lock; #endif /* * Need to completly reimplement this syscall due to argument copying. */ /* ARGSUSED */ int netbsd32_execve(l, v, retval) struct lwp *l; void *v; register_t *retval; { struct netbsd32_execve_args /* { syscallarg(const netbsd32_charp) path; syscallarg(netbsd32_charpp) argp; syscallarg(netbsd32_charpp) envp; } */ *uap = v; struct sys_execve_args ua; caddr_t sg; struct proc *p = l->l_proc; NETBSD32TOP_UAP(path, const char); NETBSD32TOP_UAP(argp, char *); NETBSD32TOP_UAP(envp, char *); sg = stackgap_init(p, 0); CHECK_ALT_EXIST(p, &sg, SCARG(&ua, path)); return netbsd32_execve2(l, &ua, retval); } int netbsd32_execve2(l, uap, retval) struct lwp *l; struct sys_execve_args *uap; register_t *retval; { /* Function args */ struct proc *p = l->l_proc; int error, i; struct exec_package pack; struct nameidata nid; struct vattr attr; struct ucred *cred = p->p_ucred; char *argp; netbsd32_charp const *cpp; char *dp; netbsd32_charp sp; long argc, envc; size_t len; char *stack; struct ps_strings arginfo; struct vmspace *vm; char **tmpfap; int szsigcode; struct exec_vmcmd *base_vcp = NULL; /* * Init the namei data to point the file user's program name. * This is done here rather than in check_exec(), so that it's * possible to override this settings if any of makecmd/probe * functions call check_exec() recursively - for example, * see exec_script_makecmds(). */ NDINIT(&nid, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), p); /* * initialize the fields of the exec package. */ pack.ep_name = SCARG(uap, path); pack.ep_hdr = malloc(exec_maxhdrsz, M_EXEC, M_WAITOK); pack.ep_hdrlen = exec_maxhdrsz; pack.ep_hdrvalid = 0; pack.ep_ndp = &nid; pack.ep_emul_arg = NULL; pack.ep_vmcmds.evs_cnt = 0; pack.ep_vmcmds.evs_used = 0; pack.ep_vap = &attr; pack.ep_flags = 0; #if defined(LKM) || defined(_LKM) lockmgr(&exec_lock, LK_SHARED, NULL); #endif /* see if we can run it. */ #ifdef VERIFIED_EXEC if ((error = check_exec(p, &pack, VERIEXEC_DIRECT)) != 0) #else if ((error = check_exec(p, &pack)) != 0) #endif goto freehdr; /* XXX -- THE FOLLOWING SECTION NEEDS MAJOR CLEANUP */ /* allocate an argument buffer */ argp = (char *) uvm_km_alloc(exec_map, NCARGS, 0, UVM_KMF_PAGEABLE|UVM_KMF_WAITVA); #ifdef DIAGNOSTIC if (argp == (vaddr_t) 0) panic("netbsd32_execve: argp == NULL"); #endif dp = argp; argc = 0; /* copy the fake args list, if there's one, freeing it as we go */ if (pack.ep_flags & EXEC_HASARGL) { tmpfap = pack.ep_fa; while (*tmpfap != NULL) { char *cp; cp = *tmpfap; while (*cp) *dp++ = *cp++; dp++; FREE(*tmpfap, M_EXEC); tmpfap++; argc++; } FREE(pack.ep_fa, M_EXEC); pack.ep_flags &= ~EXEC_HASARGL; } /* Now get argv & environment */ if (!(cpp = (netbsd32_charp *)SCARG(uap, argp))) { error = EINVAL; goto bad; } if (pack.ep_flags & EXEC_SKIPARG) cpp++; while (1) { len = argp + ARG_MAX - dp; if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) goto bad; if (!sp) break; if ((error = copyinstr((char *)(u_long)sp, dp, len, &len)) != 0) { if (error == ENAMETOOLONG) error = E2BIG; goto bad; } dp += len; cpp++; argc++; } envc = 0; /* environment need not be there */ if ((cpp = (netbsd32_charp *)SCARG(uap, envp)) != NULL ) { while (1) { len = argp + ARG_MAX - dp; if ((error = copyin(cpp, &sp, sizeof(sp))) != 0) goto bad; if (!sp) break; if ((error = copyinstr((char *)(u_long)sp, dp, len, &len)) != 0) { if (error == ENAMETOOLONG) error = E2BIG; goto bad; } dp += len; cpp++; envc++; } } dp = (char *) ALIGN(dp); szsigcode = pack.ep_es->es_emul->e_esigcode - pack.ep_es->es_emul->e_sigcode; /* Now check if args & environ fit into new stack */ if (pack.ep_flags & EXEC_32) len = ((argc + envc + 2 + pack.ep_es->es_arglen) * sizeof(int) + sizeof(int) + dp + STACKGAPLEN + szsigcode + sizeof(struct ps_strings)) - argp; else len = ((argc + envc + 2 + pack.ep_es->es_arglen) * sizeof(char *) + sizeof(int) + dp + STACKGAPLEN + szsigcode + sizeof(struct ps_strings)) - argp; len = ALIGN(len); /* make the stack "safely" aligned */ if (len > pack.ep_ssize) { /* in effect, compare to initial limit */ error = ENOMEM; goto bad; } /* adjust "active stack depth" for process VSZ */ pack.ep_ssize = len; /* maybe should go elsewhere, but... */ /* * Do whatever is necessary to prepare the address space * for remapping. Note that this might replace the current * vmspace with another! */ uvmspace_exec(l, VM_MIN_ADDRESS, (vaddr_t)pack.ep_minsaddr); /* Now map address space */ vm = p->p_vmspace; vm->vm_taddr = (char *) pack.ep_taddr; vm->vm_tsize = btoc(pack.ep_tsize); vm->vm_daddr = (char *) pack.ep_daddr; vm->vm_dsize = btoc(pack.ep_dsize); vm->vm_ssize = btoc(pack.ep_ssize); vm->vm_maxsaddr = (char *) pack.ep_maxsaddr; vm->vm_minsaddr = (char *) pack.ep_minsaddr; /* create the new process's VM space by running the vmcmds */ #ifdef DIAGNOSTIC if (pack.ep_vmcmds.evs_used == 0) panic("netbsd32_execve: no vmcmds"); #endif for (i = 0; i < pack.ep_vmcmds.evs_used && !error; i++) { struct exec_vmcmd *vcp; vcp = &pack.ep_vmcmds.evs_cmds[i]; if (vcp->ev_flags & VMCMD_RELATIVE) { #ifdef DIAGNOSTIC if (base_vcp == NULL) panic("netbsd32_execve: relative vmcmd with no base"); if (vcp->ev_flags & VMCMD_BASE) panic("netbsd32_execve: illegal base & relative vmcmd"); #endif vcp->ev_addr += base_vcp->ev_addr; } error = (*vcp->ev_proc)(p, vcp); #ifdef DEBUG if (error) { int j; for (j = 0; j <= i; j++) printf("vmcmd[%d] = %#lx/%#lx @ %#lx\n", j, vcp[j-i].ev_addr, vcp[j-i].ev_len, vcp[j-i].ev_offset); } #endif if (vcp->ev_flags & VMCMD_BASE) base_vcp = vcp; } /* free the vmspace-creation commands, and release their references */ kill_vmcmds(&pack.ep_vmcmds); /* if an error happened, deallocate and punt */ if (error) { #ifdef DEBUG printf("netbsd32_execve: vmcmd %i failed: %d\n", i-1, error); #endif goto exec_abort; } /* remember information about the process */ arginfo.ps_nargvstr = argc; arginfo.ps_nenvstr = envc; stack = (char *) (vm->vm_minsaddr - len); /* Now copy argc, args & environ to new stack */ error = (*pack.ep_es->es_copyargs)(p, &pack, &arginfo, &stack, argp); if (error) { #ifdef DEBUG printf("netbsd32_execve: copyargs failed\n"); #endif goto exec_abort; } /* restore the stack back to its original point */ stack = (char *) (vm->vm_minsaddr - len); /* fill process ps_strings info */ p->p_psstr = (struct ps_strings *)(vm->vm_minsaddr - sizeof(struct ps_strings)); p->p_psargv = offsetof(struct ps_strings, ps_argvstr); p->p_psnargv = offsetof(struct ps_strings, ps_nargvstr); p->p_psenv = offsetof(struct ps_strings, ps_envstr); p->p_psnenv = offsetof(struct ps_strings, ps_nenvstr); /* copy out the process's ps_strings structure */ if (copyout(&arginfo, (char *)p->p_psstr, sizeof(arginfo))) { #ifdef DEBUG printf("netbsd32_execve: ps_strings copyout failed\n"); #endif goto exec_abort; } /* copy out the process's signal trapoline code */ if (szsigcode) { if (copyout((char *)pack.ep_es->es_emul->e_sigcode, p->p_sigctx.ps_sigcode = (char *)p->p_psstr - szsigcode, szsigcode)) { #ifdef DEBUG printf("netbsd32_execve: sig trampoline copyout failed\n"); #endif goto exec_abort; } #ifdef PMAP_NEED_PROCWR /* This is code. Let the pmap do what is needed. */ pmap_procwr(p, (vaddr_t)p->p_sigctx.ps_sigcode, szsigcode); #endif } stopprofclock(p); /* stop profiling */ fdcloseexec(p); /* handle close on exec */ execsigs(p); /* reset catched signals */ l->l_ctxlink = NULL; /* reset ucontext link */ /* set command name & other accounting info */ len = min(nid.ni_cnd.cn_namelen, MAXCOMLEN); memcpy(p->p_comm, nid.ni_cnd.cn_nameptr, len); p->p_comm[len] = 0; p->p_acflag &= ~AFORK; /* record proc's vnode, for use by procfs and others */ if (p->p_textvp) vrele(p->p_textvp); VREF(pack.ep_vp); p->p_textvp = pack.ep_vp; p->p_flag |= P_EXEC; if (p->p_flag & P_PPWAIT) { p->p_flag &= ~P_PPWAIT; wakeup((caddr_t) p->p_pptr); } /* * deal with set[ug]id. * MNT_NOSUID has already been used to disable s[ug]id. */ if ((p->p_flag & P_TRACED) == 0 && (((attr.va_mode & S_ISUID) != 0 && p->p_ucred->cr_uid != attr.va_uid) || ((attr.va_mode & S_ISGID) != 0 && p->p_ucred->cr_gid != attr.va_gid))) { /* * Mark the process as SUGID before we do * anything that might block. */ p_sugid(p); p->p_ucred = crcopy(cred); #ifdef KTRACE /* * If process is being ktraced, turn off - unless * root set it. */ if (p->p_tracep && !(p->p_traceflag & KTRFAC_ROOT)) ktrderef(p); #endif if (attr.va_mode & S_ISUID) p->p_ucred->cr_uid = attr.va_uid; if (attr.va_mode & S_ISGID) p->p_ucred->cr_gid = attr.va_gid; } else p->p_flag &= ~P_SUGID; p->p_cred->p_svuid = p->p_ucred->cr_uid; p->p_cred->p_svgid = p->p_ucred->cr_gid; doexechooks(p); uvm_km_free(exec_map, (vaddr_t) argp, NCARGS, UVM_KMF_PAGEABLE); PNBUF_PUT(nid.ni_cnd.cn_pnbuf); vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY); VOP_CLOSE(pack.ep_vp, FREAD, cred, p); vput(pack.ep_vp); /* setup new registers and do misc. setup. */ (*pack.ep_es->es_emul->e_setregs)(l, &pack, (u_long) stack); if (pack.ep_es->es_setregs) (*pack.ep_es->es_setregs)(l, &pack, (u_long) stack); if (p->p_flag & P_TRACED) psignal(p, SIGTRAP); free(pack.ep_hdr, M_EXEC); /* * Call emulation specific exec hook. This can setup setup per-process * p->p_emuldata or do any other per-process stuff an emulation needs. * * If we are executing process of different emulation than the * original forked process, call e_proc_exit() of the old emulation * first, then e_proc_exec() of new emulation. If the emulation is * same, the exec hook code should deallocate any old emulation * resources held previously by this process. */ if (p->p_emul && p->p_emul->e_proc_exit && p->p_emul != pack.ep_es->es_emul) (*p->p_emul->e_proc_exit)(p); /* * Call exec hook. Emulation code may NOT store reference to anything * from &pack. */ if (pack.ep_es->es_emul->e_proc_exec) (*pack.ep_es->es_emul->e_proc_exec)(p, &pack); /* update p_emul, the old value is no longer needed */ p->p_emul = pack.ep_es->es_emul; /* ...and the same for p_execsw */ p->p_execsw = pack.ep_es; #ifdef __HAVE_SYSCALL_INTERN (*p->p_emul->e_syscall_intern)(p); #endif #ifdef KTRACE if (KTRPOINT(p, KTR_EMUL)) ktremul(p); #endif #if defined(LKM) || defined(_LKM) lockmgr(&exec_lock, LK_RELEASE, NULL); #endif return (EJUSTRETURN); bad: /* free the vmspace-creation commands, and release their references */ kill_vmcmds(&pack.ep_vmcmds); /* kill any opened file descriptor, if necessary */ if (pack.ep_flags & EXEC_HASFD) { pack.ep_flags &= ~EXEC_HASFD; (void) fdrelease(p, pack.ep_fd); } /* close and put the exec'd file */ vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY); VOP_CLOSE(pack.ep_vp, FREAD, cred, p); vput(pack.ep_vp); PNBUF_PUT(nid.ni_cnd.cn_pnbuf); uvm_km_free(exec_map, (vaddr_t) argp, NCARGS, UVM_KMF_PAGEABLE); freehdr: #if defined(LKM) || defined(_LKM) lockmgr(&exec_lock, LK_RELEASE, NULL); #endif free(pack.ep_hdr, M_EXEC); return error; exec_abort: #if defined(LKM) || defined(_LKM) lockmgr(&exec_lock, LK_RELEASE, NULL); #endif /* * the old process doesn't exist anymore. exit gracefully. * get rid of the (new) address space we have created, if any, get rid * of our namei data and vnode, and exit noting failure */ uvm_deallocate(&vm->vm_map, VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS - VM_MIN_ADDRESS); if (pack.ep_emul_arg) FREE(pack.ep_emul_arg, M_TEMP); PNBUF_PUT(nid.ni_cnd.cn_pnbuf); vn_lock(pack.ep_vp, LK_EXCLUSIVE | LK_RETRY); VOP_CLOSE(pack.ep_vp, FREAD, cred, p); vput(pack.ep_vp); uvm_km_free(exec_map, (vaddr_t) argp, NCARGS, UVM_KMF_PAGEABLE); free(pack.ep_hdr, M_EXEC); exit1(l, W_EXITCODE(error, SIGABRT)); /* NOTREACHED */ return 0; }