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| author | Eric W. Biederman <ebiederm@xmission.com> | 2015-01-07 21:28:26 +0100 |
|---|---|---|
| committer | Eric W. Biederman <ebiederm@xmission.com> | 2015-04-09 18:38:31 +0200 |
| commit | cd4a40174b71acd021877341684d8bb1dc8ea4ae (patch) | |
| tree | 58a7f55022d02103e77f5a8005134c863bd24b4e | |
| parent | mnt: Don't propagate unmounts to locked mounts (diff) | |
| download | linux-cd4a40174b71acd021877341684d8bb1dc8ea4ae.tar.xz linux-cd4a40174b71acd021877341684d8bb1dc8ea4ae.zip | |
mnt: Fail collect_mounts when applied to unmounted mounts
The only users of collect_mounts are in audit_tree.c
In audit_trim_trees and audit_add_tree_rule the path passed into
collect_mounts is generated from kern_path passed an audit_tree
pathname which is guaranteed to be an absolute path. In those cases
collect_mounts is obviously intended to work on mounted paths and
if a race results in paths that are unmounted when collect_mounts
it is reasonable to fail early.
The paths passed into audit_tag_tree don't have the absolute path
check. But are used to play with fsnotify and otherwise interact with
the audit_trees, so again operating only on mounted paths appears
reasonable.
Avoid having to worry about what happens when we try and audit
unmounted filesystems by restricting collect_mounts to mounts
that appear in the mount tree.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
| -rw-r--r-- | fs/namespace.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 2b12b7a9455d..acc5583764dc 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1669,8 +1669,11 @@ struct vfsmount *collect_mounts(struct path *path) { struct mount *tree; namespace_lock(); - tree = copy_tree(real_mount(path->mnt), path->dentry, - CL_COPY_ALL | CL_PRIVATE); + if (!check_mnt(real_mount(path->mnt))) + tree = ERR_PTR(-EINVAL); + else + tree = copy_tree(real_mount(path->mnt), path->dentry, + CL_COPY_ALL | CL_PRIVATE); namespace_unlock(); if (IS_ERR(tree)) return ERR_CAST(tree); |