The unveil("/", "x") is to support command executation:
daemon facility. Optionally, an alert can be configured to execute a
command.
Your proposal breaks that. It will need to be added back.
Alexander Bluhm <[email protected]> wrote:
> Hi,
>
> sensorsd(8) reports an unveil failure due to chdir / . An additional
> "r" permission would be necessary.
>
> - chdir before unveil, do not unveil /
> - use absolute config path after chdir, also necessary for SIGHUP
> - /etc/sensorsd.conf.db must be unveiled, cgetent(3) tries to open it
>
> ok?
>
> bluhm
>
> Index: usr.sbin/sensorsd/sensorsd.c
> ===================================================================
> RCS file: /data/mirror/openbsd/cvs/src/usr.sbin/sensorsd/sensorsd.c,v
> retrieving revision 1.66
> diff -u -p -r1.66 sensorsd.c
> --- usr.sbin/sensorsd/sensorsd.c 28 Jun 2019 13:32:50 -0000 1.66
> +++ usr.sbin/sensorsd/sensorsd.c 2 Jul 2020 18:14:53 -0000
> @@ -94,7 +94,7 @@ void reparse_cfg(int);
> TAILQ_HEAD(sdlimhead_t, sdlim_t);
> struct sdlimhead_t sdlims = TAILQ_HEAD_INITIALIZER(sdlims);
>
> -char *configfile;
> +char *configfile, *configdb;
> volatile sig_atomic_t reload = 0;
> int debug = 0;
>
> @@ -125,10 +125,9 @@ main(int argc, char *argv[])
> debug = 1;
> break;
> case 'f':
> - configfile = optarg;
> - if (access(configfile, R_OK) != 0)
> - err(1, "access configuration file %s",
> - configfile);
> + configfile = realpath(optarg, NULL);
> + if (configfile == NULL)
> + err(1, "configuration file %s", optarg);
> break;
> default:
> usage();
> @@ -143,10 +142,13 @@ main(int argc, char *argv[])
> if (configfile == NULL)
> if (asprintf(&configfile, "/etc/sensorsd.conf") == -1)
> err(1, "out of memory");
> + if (asprintf(&configdb, "%s.db", configfile) == -1)
> + err(1, "out of memory");
>
> + chdir("/");
> if (unveil(configfile, "r") == -1)
> err(1, "unveil");
> - if (unveil("/", "x") == -1)
> + if (unveil(configdb, "r") == -1)
> err(1, "unveil");
>
> if (pledge("stdio rpath proc exec", NULL) == -1)
> @@ -158,7 +160,7 @@ main(int argc, char *argv[])
>
> parse_config(configfile);
>
> - if (debug == 0 && daemon(0, 0) == -1)
> + if (debug == 0 && daemon(1, 0) == -1)
> err(1, "unable to fork");
>
> signal(SIGHUP, reparse_cfg);
>
