vmd(8): migrate vmd_vm.vm_ttyname to char array.

Other structs use a fixed length array already. This allows a vmd_vm
object to be transmitted over an ipc channel, too.

Additionally, solves a segfault caused by a strlcpy(3) in an error
path.

ok mlarkin@

diff --git a/usr.sbin/vmd/config.c b/usr.sbin/vmd/config.c
index 922e6cc..cc88551 100644 (file)
--- a/usr.sbin/vmd/config.c
+++ b/usr.sbin/vmd/config.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: config.c,v 1.68 2023/02/22 10:04:45 mbuhl Exp $       */
+/*     $OpenBSD: config.c,v 1.69 2023/04/02 02:04:10 dv Exp $  */
 
 /*
  * Copyright (c) 2015 Reyk Floeter <reyk@openbsd.org>
@@ -451,10 +451,10 @@ config_setvm(struct privsep *ps, struct vmd_vm *vm, uint32_t peerid, uid_t uid)
        }
 
        /* Open TTY */
-       if (vm->vm_ttyname == NULL) {
+       if (vm->vm_ttyname[0] == '\0') {
                if (vm_opentty(vm) == -1) {
                        log_warn("%s: can't open tty %s", __func__,
-                           vm->vm_ttyname == NULL ? "" : vm->vm_ttyname);
+                           vm->vm_ttyname[0] == '\0' ? "" : vm->vm_ttyname);
                        goto fail;
                }
        }

diff --git a/usr.sbin/vmd/vmd.c b/usr.sbin/vmd/vmd.c
index f604282..75af37a 100644 (file)
--- a/usr.sbin/vmd/vmd.c
+++ b/usr.sbin/vmd/vmd.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vmd.c,v 1.138 2023/01/28 14:40:53 dv Exp $    */
+/*     $OpenBSD: vmd.c,v 1.139 2023/04/02 02:04:10 dv Exp $    */
 
 /*
  * Copyright (c) 2015 Reyk Floeter <reyk@openbsd.org>
@@ -489,7 +489,7 @@ vmd_dispatch_vmm(int fd, struct privsep_proc *p, struct imsg *imsg)
                memcpy(&vir, imsg->data, sizeof(vir));
                if ((vm = vm_getbyvmid(vir.vir_info.vir_id)) != NULL) {
                        memset(vir.vir_ttyname, 0, sizeof(vir.vir_ttyname));
-                       if (vm->vm_ttyname != NULL)
+                       if (vm->vm_ttyname[0] != '\0')
                                strlcpy(vir.vir_ttyname, vm->vm_ttyname,
                                    sizeof(vir.vir_ttyname));
                        log_debug("%s: running vm: %d, vm_state: 0x%x",
@@ -1789,8 +1789,11 @@ vm_opentty(struct vmd_vm *vm)
 
        vm->vm_tty = ptm.cfd;
        close(ptm.sfd);
-       if ((vm->vm_ttyname = strdup(ptm.sn)) == NULL)
+       if (strlcpy(vm->vm_ttyname, ptm.sn, sizeof(vm->vm_ttyname))
+           >= sizeof(vm->vm_ttyname)) {
+               log_warnx("%s: truncated ttyname", __func__);
                goto fail;
+       }
 
        uid = vm->vm_uid;
        gid = vm->vm_params.vmc_owner.gid;
@@ -1858,8 +1861,7 @@ vm_closetty(struct vmd_vm *vm)
                close(vm->vm_tty);
                vm->vm_tty = -1;
        }
-       free(vm->vm_ttyname);
-       vm->vm_ttyname = NULL;
+       memset(&vm->vm_ttyname, 0, sizeof(vm->vm_ttyname));
 }
 
 void
@@ -1954,4 +1956,3 @@ vm_terminate(struct vmd_vm *vm, const char *caller)
                vm_remove(vm, caller);
        }
 }
-

diff --git a/usr.sbin/vmd/vmd.h b/usr.sbin/vmd/vmd.h
index d04c28f..7bbbf62 100644 (file)
--- a/usr.sbin/vmd/vmd.h
+++ b/usr.sbin/vmd/vmd.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: vmd.h,v 1.114 2023/01/28 14:40:53 dv Exp $    */
+/*     $OpenBSD: vmd.h,v 1.115 2023/04/02 02:04:10 dv Exp $    */
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -286,7 +286,7 @@ struct vmd_vm {
        int                      vm_cdrom;
        int                      vm_disks[VM_MAX_DISKS_PER_VM][VM_MAX_BASE_PER_DISK];
        struct vmd_if            vm_ifs[VM_MAX_NICS_PER_VM];
-       char                    *vm_ttyname;
+       char                     vm_ttyname[VM_TTYNAME_MAX];
        int                      vm_tty;
        uint32_t                 vm_peerid;
        /* When set, VM was defined in a config file */