From e24709454c458283146485b76abfcc6d8ea964c7 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (Google)" Date: Tue, 5 Sep 2023 14:26:09 -0400 Subject: [PATCH] tracefs/eventfs: Add missing lockdown checks All the eventfs external functions do not check if TRACEFS_LOCKDOWN was set or not. This can caused some functions to return success while others fail, which can trigger unexpected errors. Add the missing lockdown checks. Link: https://lkml.kernel.org/r/20230905182711.899724045@goodmis.org Link: https://lore.kernel.org/all/202309050916.58201dc6-oliver.sang@intel.com/ Cc: Masami Hiramatsu Cc: Mark Rutland Cc: Andrew Morton Cc: Ajay Kaher Cc: Ching-lin Yu Reported-by: kernel test robot Signed-off-by: Steven Rostedt (Google) --- fs/tracefs/event_inode.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/fs/tracefs/event_inode.c b/fs/tracefs/event_inode.c index 237c6f370ad9..fa1a1679a886 100644 --- a/fs/tracefs/event_inode.c +++ b/fs/tracefs/event_inode.c @@ -491,6 +491,9 @@ struct dentry *eventfs_create_events_dir(const char *name, struct tracefs_inode *ti; struct inode *inode; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return NULL; + if (IS_ERR(dentry)) return dentry; @@ -538,6 +541,9 @@ struct eventfs_file *eventfs_add_subsystem_dir(const char *name, struct eventfs_inode *ei_parent; struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return NULL; + if (!parent) return ERR_PTR(-EINVAL); @@ -569,6 +575,9 @@ struct eventfs_file *eventfs_add_dir(const char *name, { struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return NULL; + if (!ef_parent) return ERR_PTR(-EINVAL); @@ -606,6 +615,9 @@ int eventfs_add_events_file(const char *name, umode_t mode, struct eventfs_inode *ei; struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return -ENODEV; + if (!parent) return -EINVAL; @@ -654,6 +666,9 @@ int eventfs_add_file(const char *name, umode_t mode, { struct eventfs_file *ef; + if (security_locked_down(LOCKDOWN_TRACEFS)) + return -ENODEV; + if (!ef_parent) return -EINVAL;