libsemanage: Also check for the uppoer bound on user ids in login.defs
Some non-Debian packages (like qmail, shudder) create
users not below MIN_UID, but above MAX_UID, in /etc/login.defs
(non-system users are supposed to have uids between MIN_UID and
MAX_UID.
genhomedircon.c:gethomedirs() checks pwent.pw_uid against MIN_UID in
/etc/login.defs to exclude system users from generating homedir
contexts. But unfortunately it does not check it against MAX_UID
setting from the same file. This gets us lines like the following in
the contexts/files/file_contexts.homedirs file:
,----
| #
| # Home Context for user user_u
| #
| /var/qmail/[^/]*/.+ user_u:object_r:user_home_t:s0
| /var/qmail/[^/]*/\.ssh(/.*)? user_u:object_r:user_home_ssh_t:s0
| /var/qmail/[^/]*/\.gnupg(/.+)? user_u:object_r:user_gpg_secret_t:s0
| /var/qmail/[^/]* -d user_u:object_r:user_home_dir_t:s0
| /var/qmail/lost\+found/.* <<none>>
| /var/qmail -d system_u:object_r:home_root_t:s0
| /var/qmail/\.journal <<none>>
| /var/qmail/lost\+found -d system_u:object_r:lost_found_t:s0
| /tmp/gconfd-.* -d user_u:object_r:user_tmp_t:s0
`----
This commit adds checking uid value againt MAX_UID too.
diff --git a/libsemanage/src/genhomedircon.c b/libsemanage/src/genhomedircon.c
index 3c81d7a..8af51d3 100644
--- a/libsemanage/src/genhomedircon.c
+++ b/libsemanage/src/genhomedircon.c
@@ -283,8 +283,8 @@
char *rbuf = NULL;
char *path = NULL;
long rbuflen;
- uid_t temp, minuid = 500;
- int minuid_set = 0;
+ uid_t temp, minuid = 500, maxuid = 60000;
+ int minuid_set = 0, maxuid_set = 0;
struct passwd pwstorage, *pwbuf;
struct stat buf;
int retval;
@@ -333,6 +333,15 @@
free(path);
path = NULL;
+ path = semanage_findval(PATH_ETC_LOGIN_DEFS, "UID_MAX", NULL);
+ if (path && *path) {
+ temp = atoi(path);
+ maxuid = temp;
+ maxuid_set = 1;
+ }
+ free(path);
+ path = NULL;
+
path = semanage_findval(PATH_ETC_LIBUSER, "LU_UIDNUMBER", "=");
if (path && *path) {
temp = atoi(path);
@@ -352,7 +361,7 @@
goto fail;
setpwent();
while ((retval = getpwent_r(&pwstorage, rbuf, rbuflen, &pwbuf)) == 0) {
- if (pwbuf->pw_uid < minuid)
+ if (pwbuf->pw_uid < minuid || pwbuf->pw_uid > maxuid)
continue;
if (!semanage_list_find(shells, pwbuf->pw_shell))
continue;
@@ -385,7 +394,7 @@
/* NOTE: old genhomedircon printed a warning on match */
if (hand.matched) {
- WARN(s->h_semanage, "%s homedir %s or its parent directory conflicts with a file context already specified in the policy. This usually indicates an incorrectly defined system account. If it is a system account please make sure its uid is less than %u or its login shell is /sbin/nologin.", pwbuf->pw_name, pwbuf->pw_dir, minuid);
+ WARN(s->h_semanage, "%s homedir %s or its parent directory conflicts with a file context already specified in the policy. This usually indicates an incorrectly defined system account. If it is a system account please make sure its uid is less than %u or greater than %u or its login shell is /sbin/nologin.", pwbuf->pw_name, pwbuf->pw_dir, minuid, maxuid);
} else {
if (semanage_list_push(&homedir_list, path))
goto fail;
