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
This commit is contained in:
Daniel Rosenberg 2017-01-05 14:37:11 -08:00 committed by Artem Borisov
parent cd769ec65b
commit fdfefc2e98
2 changed files with 22 additions and 7 deletions

View File

@ -395,16 +395,31 @@ 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;
}

View File

@ -38,7 +38,7 @@ int propagate_mnt(struct mount *, struct dentry *, struct mount *,
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);