Merge v7.1.5linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/security/landlock/fs.c b/security/landlock/fs.c
index c1ecfe239032..664962a416d7 100644
--- a/security/landlock/fs.c
+++ b/security/landlock/fs.c
@@ -1901,6 +1901,14 @@ static bool control_current_fowner(struct fown_struct *const fown)
 	lockdep_assert_held(&fown->lock);
 
 	/*
+	 * A process-group or session owner (PIDTYPE_PGID/PIDTYPE_SID) fans the
+	 * signal out to every member at delivery time, so record the domain and
+	 * let hook_file_send_sigiotask() check the live scope per recipient.
+	 */
+	if (fown->pid_type != PIDTYPE_PID && fown->pid_type != PIDTYPE_TGID)
+		return true;
+
+	/*
 	 * Some callers (e.g. fcntl_dirnotify) may not be in an RCU read-side
 	 * critical section.
 	 */
@@ -1916,6 +1924,7 @@ static void hook_file_set_fowner(struct file *file)
 {
 	struct landlock_ruleset *prev_dom;
 	struct landlock_cred_security fown_subject = {};
+	struct pid *prev_tg, *fown_tg = NULL;
 	size_t fown_layer = 0;
 
 	if (control_current_fowner(file_f_owner(file))) {
@@ -1928,21 +1937,26 @@ static void hook_file_set_fowner(struct file *file)
 		if (new_subject) {
 			landlock_get_ruleset(new_subject->domain);
 			fown_subject = *new_subject;
+			fown_tg = get_pid(task_tgid(current));
 		}
 	}
 
 	prev_dom = landlock_file(file)->fown_subject.domain;
+	prev_tg = landlock_file(file)->fown_tg;
 	landlock_file(file)->fown_subject = fown_subject;
+	landlock_file(file)->fown_tg = fown_tg;
 #ifdef CONFIG_AUDIT
 	landlock_file(file)->fown_layer = fown_layer;
 #endif /* CONFIG_AUDIT*/
 
 	/* May be called in an RCU read-side critical section. */
 	landlock_put_ruleset_deferred(prev_dom);
+	put_pid(prev_tg);
 }
 
 static void hook_file_free_security(struct file *file)
 {
+	put_pid(landlock_file(file)->fown_tg);
 	landlock_put_ruleset_deferred(landlock_file(file)->fown_subject.domain);
 }