| Message ID | 1428026183-14879-9-git-send-email-ebiederm@xmission.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On czw, 2015-04-02 at 20:56 -0500, Eric W. Biederman wrote: > The only users of collect_mounts are in audit_tree.c > > In audit_tree_trees and audit_add_tree rule the path passed into I think you meant audit_trim_trees. Also you missed a _ in audit_add_tree_rule. > 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> > --- > fs/namespace.c | 7 +++++-- > 1 file 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);
Lukasz Pawelczyk <l.pawelczyk@samsung.com> writes: > On czw, 2015-04-02 at 20:56 -0500, Eric W. Biederman wrote: >> The only users of collect_mounts are in audit_tree.c >> >> In audit_tree_trees and audit_add_tree rule the path passed into > > I think you meant audit_trim_trees. > > Also you missed a _ in audit_add_tree_rule. I did thank you. Eric -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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);
The only users of collect_mounts are in audit_tree.c In audit_tree_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> --- fs/namespace.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)