eventfs: Do not allow NULL parent to eventfs_start_creating()

The eventfs directory is dynamically created via the meta data supplied by
the existing trace events. All files and directories in eventfs has a
parent. Do not allow NULL to be passed into eventfs_start_creating() as
the parent because that should never happen. Warn if it does.

Link: https://lkml.kernel.org/r/20231121231112.693841807@goodmis.org

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt (Google) 2023-11-21 18:10:06 -05:00
parent bcae32c563
commit fc4561226f
1 changed files with 4 additions and 9 deletions

View File

@ -509,20 +509,15 @@ struct dentry *eventfs_start_creating(const char *name, struct dentry *parent)
struct dentry *dentry;
int error;
/* Must always have a parent. */
if (WARN_ON_ONCE(!parent))
return ERR_PTR(-EINVAL);
error = simple_pin_fs(&trace_fs_type, &tracefs_mount,
&tracefs_mount_count);
if (error)
return ERR_PTR(error);
/*
* If the parent is not specified, we create it in the root.
* We need the root dentry to do this, which is in the super
* block. A pointer to that is in the struct vfsmount that we
* have around.
*/
if (!parent)
parent = tracefs_mount->mnt_root;
if (unlikely(IS_DEADDIR(parent->d_inode)))
dentry = ERR_PTR(-ENOENT);
else