fix the struct mount leak in umount_tree()
We need to drop everything we remove from the tree, whether
mnt_has_parent() is true or not. Usually the bug manifests as a slow
memory leak (leaked struct mount for initramfs); it becomes much more
visible in mount_subtree() users, such as btrfs. There we leak
a struct mount for btrfs superblock being mounted, which prevents
fs shutdown on subsequent umount.
Fixes: 56cbb429d9
("switch the remnants of releasing the mountpoint away from fs_pin")
Reported-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
parent
18253e034d
commit
19a1c4092e
|
@ -1463,7 +1463,6 @@ static void umount_tree(struct mount *mnt, enum umount_tree_flags how)
|
|||
p->mnt.mnt_flags |= MNT_SYNC_UMOUNT;
|
||||
|
||||
disconnect = disconnect_mount(p, how);
|
||||
|
||||
if (mnt_has_parent(p)) {
|
||||
mnt_add_count(p->mnt_parent, -1);
|
||||
if (!disconnect) {
|
||||
|
@ -1471,10 +1470,11 @@ static void umount_tree(struct mount *mnt, enum umount_tree_flags how)
|
|||
list_add_tail(&p->mnt_child, &p->mnt_parent->mnt_mounts);
|
||||
} else {
|
||||
umount_mnt(p);
|
||||
hlist_add_head(&p->mnt_umount, &unmounted);
|
||||
}
|
||||
}
|
||||
change_mnt_propagation(p, MS_PRIVATE);
|
||||
if (disconnect)
|
||||
hlist_add_head(&p->mnt_umount, &unmounted);
|
||||
}
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in a new issue