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| author | Joel Stanley <joel@jms.id.au> | 2018-11-27 08:23:56 +0300 |
|---|---|---|
| committer | Joel Stanley <joel@jms.id.au> | 2018-11-27 08:24:09 +0300 |
| commit | d608acfd4ac3fe17f3081bee8fcd4dcd896c2ffa (patch) | |
| tree | ade4450a72a2e358a1d2e5cde321de0097fb291c /fs/namespace.c | |
| parent | 62ccc3924eff37012bd0c227d8b7dc71188fc358 (diff) | |
| parent | a9da8725b7a744be3ff0ff44cab2547e4d1e6675 (diff) | |
| download | linux-dev-4.18.tar.xz | |
Merge tag 'v4.18.20' into dev-4.18dev-4.18
This is the 4.18.20 stable release
Signed-off-by: Joel Stanley <joel@jms.id.au>
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 28 |
1 files changed, 20 insertions, 8 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index bd2f4c68506a..e65254003cad 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -780,9 +780,6 @@ static struct mountpoint *lookup_mountpoint(struct dentry *dentry) hlist_for_each_entry(mp, chain, m_hash) { if (mp->m_dentry == dentry) { - /* might be worth a WARN_ON() */ - if (d_unlinked(dentry)) - return ERR_PTR(-ENOENT); mp->m_count++; return mp; } @@ -796,6 +793,9 @@ static struct mountpoint *get_mountpoint(struct dentry *dentry) int ret; if (d_mountpoint(dentry)) { + /* might be worth a WARN_ON() */ + if (d_unlinked(dentry)) + return ERR_PTR(-ENOENT); mountpoint: read_seqlock_excl(&mount_lock); mp = lookup_mountpoint(dentry); @@ -1625,8 +1625,13 @@ static int do_umount(struct mount *mnt, int flags) namespace_lock(); lock_mount_hash(); - event++; + /* Recheck MNT_LOCKED with the locks held */ + retval = -EINVAL; + if (mnt->mnt.mnt_flags & MNT_LOCKED) + goto out; + + event++; if (flags & MNT_DETACH) { if (!list_empty(&mnt->mnt_list)) umount_tree(mnt, UMOUNT_PROPAGATE); @@ -1640,6 +1645,7 @@ static int do_umount(struct mount *mnt, int flags) retval = 0; } } +out: unlock_mount_hash(); namespace_unlock(); return retval; @@ -1730,7 +1736,7 @@ int ksys_umount(char __user *name, int flags) goto dput_and_out; if (!check_mnt(mnt)) goto dput_and_out; - if (mnt->mnt.mnt_flags & MNT_LOCKED) + if (mnt->mnt.mnt_flags & MNT_LOCKED) /* Check optimistically */ goto dput_and_out; retval = -EPERM; if (flags & MNT_FORCE && !capable(CAP_SYS_ADMIN)) @@ -1813,8 +1819,14 @@ struct mount *copy_tree(struct mount *mnt, struct dentry *dentry, for (s = r; s; s = next_mnt(s, r)) { if (!(flag & CL_COPY_UNBINDABLE) && IS_MNT_UNBINDABLE(s)) { - s = skip_mnt_tree(s); - continue; + if (s->mnt.mnt_flags & MNT_LOCKED) { + /* Both unbindable and locked. */ + q = ERR_PTR(-EPERM); + goto out; + } else { + s = skip_mnt_tree(s); + continue; + } } if (!(flag & CL_COPY_MNT_NS_FILE) && is_mnt_ns_file(s->mnt.mnt_root)) { @@ -1867,7 +1879,7 @@ void drop_collected_mounts(struct vfsmount *mnt) { namespace_lock(); lock_mount_hash(); - umount_tree(real_mount(mnt), UMOUNT_SYNC); + umount_tree(real_mount(mnt), 0); unlock_mount_hash(); namespace_unlock(); } |