ANDROID: mnt: remount should propagate to slaves of slaves
propagate_remount was not accounting for the slave mounts
of other slave mounts, leading to some namespaces not
recieving the remount information.
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Bug: 33731928
Change-Id: Idc9e8c2ed126a4143229fc23f10a959c2d0a3854
Signed-off-by: Kevin F. Haggerty <haggertk@lineageos.org>
diff --git a/fs/pnode.c b/fs/pnode.c
index 7a20aef..f5da6dc 100644
--- a/fs/pnode.c
+++ b/fs/pnode.c
@@ -397,16 +397,31 @@
return 0;
}
-int propagate_remount(struct mount *mnt) {
- struct mount *m;
+/*
+ * Iterates over all slaves, and slaves of slaves.
+ */
+static struct mount *next_descendent(struct mount *root, struct mount *cur)
+{
+ if (!IS_MNT_NEW(cur) && !list_empty(&cur->mnt_slave_list))
+ return first_slave(cur);
+ do {
+ if (cur->mnt_slave.next != &cur->mnt_master->mnt_slave_list)
+ return next_slave(cur);
+ cur = cur->mnt_master;
+ } while (cur != root);
+ return NULL;
+}
+
+void propagate_remount(struct mount *mnt)
+{
+ struct mount *m = mnt;
struct super_block *sb = mnt->mnt.mnt_sb;
- int ret = 0;
if (sb->s_op->copy_mnt_data) {
- for (m = first_slave(mnt); m->mnt_slave.next != &mnt->mnt_slave_list; m = next_slave(m)) {
+ m = next_descendent(mnt, m);
+ while (m) {
sb->s_op->copy_mnt_data(m->mnt.data, mnt->mnt.data);
+ m = next_descendent(mnt, m);
}
}
-
- return ret;
}
diff --git a/fs/pnode.h b/fs/pnode.h
index 71fb182..7326d98 100644
--- a/fs/pnode.h
+++ b/fs/pnode.h
@@ -38,7 +38,7 @@
struct list_head *);
int propagate_umount(struct list_head *);
int propagate_mount_busy(struct mount *, int);
-int propagate_remount(struct mount *);
+void propagate_remount(struct mount *);
void mnt_release_group_id(struct mount *);
int get_dominating_id(struct mount *mnt, const struct path *root);
unsigned int mnt_get_count(struct mount *mnt);