diff mbox series

[for-linus,01/15] tracefs: Add missing lockdown check to tracefs_create_dir()

Message ID 20230909032348.185808168@goodmis.org
State New
Headers
Series [for-linus,01/15] tracefs: Add missing lockdown check to tracefs_create_dir() |

Commit Message

Steven Rostedt Sept. 9, 2023, 3:16 a.m. UTC 
  From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

The function tracefs_create_dir() was missing a lockdown check and was
called by the RV code. This gave an inconsistent behavior of this function
returning success while other tracefs functions failed. This caused the
inode being freed by the wrong kmem_cache.

Link: https://lkml.kernel.org/r/20230905182711.692687042@goodmis.org
Link: https://lore.kernel.org/all/202309050916.58201dc6-oliver.sang@intel.com/

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Ajay Kaher <akaher@vmware.com>
Cc: Ching-lin Yu <chinglinyu@google.com>
Fixes: bf8e602186ec4 ("tracing: Do not create tracefs files if tracefs lockdown is in effect")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 fs/tracefs/inode.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/fs/tracefs/inode.c b/fs/tracefs/inode.c
index de5b72216b1a..3b8dd938b1c8 100644
--- a/fs/tracefs/inode.c
+++ b/fs/tracefs/inode.c
@@ -673,6 +673,9 @@  static struct dentry *__create_dir(const char *name, struct dentry *parent,
  */
 struct dentry *tracefs_create_dir(const char *name, struct dentry *parent)
 {
+	if (security_locked_down(LOCKDOWN_TRACEFS))
+		return NULL;
+
 	return __create_dir(name, parent, &simple_dir_inode_operations);
 }