ucount: Make sure ucounts in /proc/sys/user don't regress again

Commit 769071a "ns: Introduce Time Namespace" broke reporting of inotify ucounts (max_inotify_instances, max_inotify_watches) in /proc/sys/user because it has added UCOUNT_TIME_NAMESPACES into enum ucount_type but didn't properly update reporting in kernel/ucount.c:setup_userns_sysctls(). This problem got fixed in commit eeec26d "time/namespace: Add max_time_namespaces ucount". Add BUILD_BUG_ON to catch a similar problem in the future. Signed-off-by: Jan Kara <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Acked-by: Andrei Vagin <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
fracktal · Apr 7, 2020 · 0f538e3 · 0f538e3
1 parent eeec26d
commit 0f538e3
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/kernel/ucount.c b/kernel/ucount.c
@@ -82,6 +82,8 @@ bool setup_userns_sysctls(struct user_namespace *ns)
 {
 #ifdef CONFIG_SYSCTL
 	struct ctl_table *tbl;
+
+	BUILD_BUG_ON(ARRAY_SIZE(user_table) != UCOUNT_COUNTS + 1);
 	setup_sysctl_set(&ns->set, &set_root, set_is_seen);
 	tbl = kmemdup(user_table, sizeof(user_table), GFP_KERNEL);
 	if (tbl) {