static int do_exec(int proc_e, char *exec, size_t exec_len, char *progname, char *frame, int frame_len) { int r; vir_bytes vsp; struct exec_info execi; int i; memset(&execi, 0, sizeof(execi)); execi.stack_size = DEFAULT_STACK_LIMIT; execi.proc_e = proc_e; execi.hdr = exec; execi.hdr_len = exec_len; strncpy(execi.progname, progname, PROC_NAME_LEN-1); execi.progname[PROC_NAME_LEN-1] = '\0'; execi.frame_len = frame_len; /* callback functions and data */ execi.copymem = read_seg; execi.clearproc = libexec_clearproc_vm_procctl; execi.clearmem = libexec_clear_sys_memset; execi.allocmem_prealloc = libexec_alloc_mmap_prealloc; execi.allocmem_ondemand = libexec_alloc_mmap_ondemand; for(i = 0; exec_loaders[i].load_object != NULL; i++) { r = (*exec_loaders[i].load_object)(&execi); /* Loaded successfully, so no need to try other loaders */ if (r == OK) break; } /* No exec loader could load the object */ if (r != OK) { printf("RS: do_exec: loading error %d\n", r); return r; } /* Inform PM */ if((r = libexec_pm_newexec(execi.proc_e, &execi)) != OK) return r; /* Patch up stack and copy it from RS to new core image. */ vsp = execi.stack_high; vsp -= frame_len; libexec_patch_ptr(frame, vsp); r = sys_datacopy(SELF, (vir_bytes) frame, proc_e, (vir_bytes) vsp, (phys_bytes)frame_len); if (r != OK) { printf("do_exec: copying out new stack failed: %d\n", r); exec_restart(proc_e, r, execi.pc); return r; } return exec_restart(proc_e, OK, execi.pc); }
/*===========================================================================* * pm_exec * *===========================================================================*/ int pm_exec(endpoint_t proc_e, vir_bytes path, size_t path_len, vir_bytes frame, size_t frame_len, vir_bytes *pc, vir_bytes *newsp, int user_exec_flags) { /* Perform the execve(name, argv, envp) call. The user library builds a * complete stack image, including pointers, args, environ, etc. The stack * is copied to a buffer inside VFS, and then to the new core image. */ int r, slot; vir_bytes vsp; struct fproc *rfp; int extrabase = 0; static char mbuf[ARG_MAX]; /* buffer for stack and zeroes */ struct vfs_exec_info execi; int i; static char fullpath[PATH_MAX], elf_interpreter[PATH_MAX], firstexec[PATH_MAX], finalexec[PATH_MAX]; struct lookup resolve; struct fproc *vmfp = &fproc[VM_PROC_NR]; stackhook_t makestack = NULL; static int n; n++; struct filp *newfilp = NULL; lock_exec(); lock_proc(vmfp, 0); /* unset execi values are 0. */ memset(&execi, 0, sizeof(execi)); execi.vmfd = -1; /* passed from exec() libc code */ execi.userflags = user_exec_flags; execi.args.stack_high = kinfo.user_sp; execi.args.stack_size = DEFAULT_STACK_LIMIT; okendpt(proc_e, &slot); rfp = fp = &fproc[slot]; lookup_init(&resolve, fullpath, PATH_NOFLAGS, &execi.vmp, &execi.vp); resolve.l_vmnt_lock = VMNT_READ; resolve.l_vnode_lock = VNODE_READ; /* Fetch the stack from the user before destroying the old core image. */ if (frame_len > ARG_MAX) FAILCHECK(ENOMEM); /* stack too big */ r = sys_datacopy(proc_e, (vir_bytes) frame, SELF, (vir_bytes) mbuf, (size_t) frame_len); if (r != OK) { /* can't fetch stack (e.g. bad virtual addr) */ printf("VFS: pm_exec: sys_datacopy failed\n"); FAILCHECK(r); } /* The default is to keep the original user and group IDs */ execi.args.new_uid = rfp->fp_effuid; execi.args.new_gid = rfp->fp_effgid; /* Get the exec file name. */ FAILCHECK(fetch_name(path, path_len, fullpath)); strlcpy(finalexec, fullpath, PATH_MAX); strlcpy(firstexec, fullpath, PATH_MAX); /* Get_read_vp will return an opened vn in execi. * if necessary it releases the existing vp so we can * switch after we find out what's inside the file. * It reads the start of the file. */ Get_read_vp(execi, fullpath, 1, 1, &resolve, fp); /* If this is a script (i.e. has a #!/interpreter line), * retrieve the name of the interpreter and open that * executable instead. */ if(is_script(&execi)) { /* patch_stack will add interpreter name and * args to stack and retrieve the new binary * name into fullpath. */ FAILCHECK(fetch_name(path, path_len, fullpath)); FAILCHECK(patch_stack(execi.vp, mbuf, &frame_len, fullpath)); strlcpy(finalexec, fullpath, PATH_MAX); strlcpy(firstexec, fullpath, PATH_MAX); Get_read_vp(execi, fullpath, 1, 0, &resolve, fp); } /* If this is a dynamically linked executable, retrieve * the name of that interpreter in elf_interpreter and open that * executable instead. But open the current executable in an * fd for the current process. */ if(elf_has_interpreter(execi.args.hdr, execi.args.hdr_len, elf_interpreter, sizeof(elf_interpreter))) { /* Switch the executable vnode to the interpreter */ execi.is_dyn = 1; /* The interpreter (loader) needs an fd to the main program, * which is currently in finalexec */ if((r = execi.elf_main_fd = common_open(finalexec, O_RDONLY, 0)) < 0) { printf("VFS: exec: dynamic: open main exec failed %s (%d)\n", fullpath, r); FAILCHECK(r); } /* ld.so is linked at 0, but it can relocate itself; we * want it higher to trap NULL pointer dereferences. */ execi.args.load_offset = 0x10000; /* Remember it */ strlcpy(execi.execname, finalexec, PATH_MAX); /* The executable we need to execute first (loader) * is in elf_interpreter, and has to be in fullpath to * be looked up */ strlcpy(fullpath, elf_interpreter, PATH_MAX); strlcpy(firstexec, elf_interpreter, PATH_MAX); Get_read_vp(execi, fullpath, 0, 0, &resolve, fp); } /* We also want an FD for VM to mmap() the process in if possible. */ { struct vnode *vp = execi.vp; assert(vp); if(vp->v_vmnt->m_haspeek && major(vp->v_dev) != MEMORY_MAJOR) { int newfd = -1; if(get_fd(vmfp, 0, R_BIT, &newfd, &newfilp) == OK) { assert(newfd >= 0 && newfd < OPEN_MAX); assert(!vmfp->fp_filp[newfd]); newfilp->filp_count = 1; newfilp->filp_vno = vp; newfilp->filp_flags = O_RDONLY; FD_SET(newfd, &vmfp->fp_filp_inuse); vmfp->fp_filp[newfd] = newfilp; /* dup_vnode(vp); */ execi.vmfd = newfd; execi.args.memmap = vfs_memmap; } } } /* callback functions and data */ execi.args.copymem = read_seg; execi.args.clearproc = libexec_clearproc_vm_procctl; execi.args.clearmem = libexec_clear_sys_memset; execi.args.allocmem_prealloc_cleared = libexec_alloc_mmap_prealloc_cleared; execi.args.allocmem_prealloc_junk = libexec_alloc_mmap_prealloc_junk; execi.args.allocmem_ondemand = libexec_alloc_mmap_ondemand; execi.args.opaque = &execi; execi.args.proc_e = proc_e; execi.args.frame_len = frame_len; execi.args.filesize = execi.vp->v_size; for (i = 0; exec_loaders[i].load_object != NULL; i++) { r = (*exec_loaders[i].load_object)(&execi.args); /* Loaded successfully, so no need to try other loaders */ if (r == OK) { makestack = exec_loaders[i].setup_stack; break; } } FAILCHECK(r); /* Inform PM */ FAILCHECK(libexec_pm_newexec(proc_e, &execi.args)); /* Save off PC */ *pc = execi.args.pc; /* call a stack-setup function if this executable type wants it */ vsp = execi.args.stack_high - frame_len; if(makestack) FAILCHECK(makestack(&execi, mbuf, &frame_len, &vsp, &extrabase)); /* Patch up stack and copy it from VFS to new core image. */ libexec_patch_ptr(mbuf, vsp + extrabase); FAILCHECK(sys_datacopy(SELF, (vir_bytes) mbuf, proc_e, (vir_bytes) vsp, (phys_bytes)frame_len)); /* Return new stack pointer to caller */ *newsp = vsp; clo_exec(rfp); if (execi.args.allow_setuid) { /* If after loading the image we're still allowed to run with * setuid or setgid, change credentials now */ rfp->fp_effuid = execi.args.new_uid; rfp->fp_effgid = execi.args.new_gid; } /* Remember the new name of the process */ strlcpy(rfp->fp_name, execi.args.progname, PROC_NAME_LEN); pm_execfinal: if(newfilp) unlock_filp(newfilp); else if (execi.vp != NULL) { unlock_vnode(execi.vp); put_vnode(execi.vp); } if(execi.vmfd >= 0 && !execi.vmfd_used) { if(OK != close_fd(vmfp, execi.vmfd)) { printf("VFS: unexpected close fail of vm fd\n"); } } unlock_proc(vmfp); unlock_exec(); return(r); }