From 3e28db33fcf946b16ad94d314b8850c66dd0c15b Mon Sep 17 00:00:00 2001 From: Daniel Rosenberg Date: Thu, 5 Jan 2017 14:37:11 -0800 Subject: [PATCH] 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. bug:33731928 Change-Id: Idc9e8c2ed126a4143229fc23f10a959c2d0a3854 Signed-off-by: Daniel Rosenberg --- fs/pnode.c | 27 +++++++++++++++++++++------ fs/pnode.h | 2 +- 2 files changed, 22 insertions(+), 7 deletions(-) diff --git a/fs/pnode.c b/fs/pnode.c index 69b86b61af35..cbaa998ad625 100644 --- a/fs/pnode.c +++ b/fs/pnode.c @@ -459,16 +459,31 @@ int propagate_umount(struct list_head *list) 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 4e8e94dc9e6a..3cb58c0cdcbc 100644 --- a/fs/pnode.h +++ b/fs/pnode.h @@ -44,7 +44,7 @@ int propagate_mnt(struct mount *, struct mountpoint *, struct mount *, int propagate_umount(struct list_head *); int propagate_mount_busy(struct mount *, int); void propagate_mount_unlock(struct mount *); -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); -- 2.34.1