Commit 27c04648 authored by Steven Rostedt (Google)'s avatar Steven Rostedt (Google)
Browse files

tracefs: Update inode permissions on remount 

When a remount happens, if a gid or uid is specified update the inodes to
have the same gid and uid. This will allow the simplification of the
permissions logic for the dynamically created files and directories.

Link: https://lore.kernel.org/linux-trace-kernel/20240523051539.592429986@goodmis.org



Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Fixes: baa23a8d ("tracefs: Reset permissions on remount if permissions are options")
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 8898e7f2

fs/tracefs/event_inode.c

+13 −4
Original line number Diff line number Diff line
@@ -317,20 +317,29 @@ void eventfs_remount(struct tracefs_inode *ti, bool update_uid, bool update_gid) 
	if (!ei)

		return;



	if (update_uid)

	if (update_uid) {

		ei->attr.mode &= ~EVENTFS_SAVE_UID;

		ei->attr.uid = ti->vfs_inode.i_uid;

	}





	if (update_gid)

	if (update_gid) {

		ei->attr.mode &= ~EVENTFS_SAVE_GID;

		ei->attr.gid = ti->vfs_inode.i_gid;

	}



	if (!ei->entry_attrs)

		return;



	for (int i = 0; i < ei->nr_entries; i++) {

		if (update_uid)

		if (update_uid) {

			ei->entry_attrs[i].mode &= ~EVENTFS_SAVE_UID;

		if (update_gid)

			ei->entry_attrs[i].uid = ti->vfs_inode.i_uid;

		}

		if (update_gid) {

			ei->entry_attrs[i].mode &= ~EVENTFS_SAVE_GID;

			ei->entry_attrs[i].gid = ti->vfs_inode.i_gid;

		}

	}

}

fs/tracefs/inode.c

+12 −3
Original line number Diff line number Diff line
@@ -373,12 +373,21 @@ static int tracefs_apply_options(struct super_block *sb, bool remount) 


		rcu_read_lock();

		list_for_each_entry_rcu(ti, &tracefs_inodes, list) {

			if (update_uid)

			if (update_uid) {

				ti->flags &= ~TRACEFS_UID_PERM_SET;

				ti->vfs_inode.i_uid = fsi->uid;

			}



			if (update_gid)

			if (update_gid) {

				ti->flags &= ~TRACEFS_GID_PERM_SET;

				ti->vfs_inode.i_gid = fsi->gid;

			}



			/*

			 * Note, the above ti->vfs_inode updates are

			 * used in eventfs_remount() so they must come

			 * before calling it.

			 */

			if (ti->flags & TRACEFS_EVENT_INODE)

				eventfs_remount(ti, update_uid, update_gid);

		}