From 80d7012b09cddbf6b8bb0d002af5f4645ad5c450 Mon Sep 17 00:00:00 2001 From: David Gibson Date: Mon, 12 Sep 2022 22:24:01 +1000 Subject: Consolidate determination of UID/GID to run as Currently the logic to work out what UID and GID we will run as is spread across conf(). If --runas is specified it's handled in conf_runas(), otherwise it's handled by check_root(), which depends on initialization of the uid and gid variables by either conf() itself or conf_runas(). Make this clearer by putting all the UID and GID logic into a single conf_ugid() function. Signed-off-by: David Gibson --- util.c | 50 -------------------------------------------------- 1 file changed, 50 deletions(-) (limited to 'util.c') diff --git a/util.c b/util.c index eb25c37..ce88aee 100644 --- a/util.c +++ b/util.c @@ -482,56 +482,6 @@ void drop_caps(void) } } -/** - * check_root() - Check if root in init ns, exit if we can't drop to user - */ -void check_root(uid_t *uid, gid_t *gid) -{ - const char root_uid_map[] = " 0 0 4294967295"; - struct passwd *pw; - char buf[BUFSIZ]; - int fd; - - if (!*uid) - *uid = geteuid(); - - if (!*gid) - *gid = getegid(); - - if (*uid) - return; - - if ((fd = open("/proc/self/uid_map", O_RDONLY | O_CLOEXEC)) < 0) - return; - - if (read(fd, buf, BUFSIZ) != sizeof(root_uid_map) || - strncmp(buf, root_uid_map, sizeof(root_uid_map) - 1)) { - close(fd); - return; - } - - close(fd); - - if (!*uid) { - fprintf(stderr, "Don't run as root. Changing to nobody...\n"); -#ifndef GLIBC_NO_STATIC_NSS - pw = getpwnam("nobody"); - if (!pw) { - perror("getpwnam"); - exit(EXIT_FAILURE); - } - - *uid = pw->pw_uid; - *gid = pw->pw_gid; -#else - (void)pw; - - /* Common value for 'nobody', not really specified */ - *uid = *gid = 65534; -#endif - } -} - /** * drop_root() - Switch to given UID and GID * @uid: User ID to switch to -- cgit v1.2.3