Just CC’ed to some of maintainers.

$ perl scripts/get_maintainer.pl 
fs/0001-ksys_mount-check-for-permissions-before-resource-all.patch
Alexander Viro <[email protected]> (maintainer:FILESYSTEMS (VFS and 
infrastructure))
[email protected] (open list:FILESYSTEMS (VFS and infrastructure))
[email protected] (open list)

> On Jun 5, 2018, at 6:00 AM, Ilya Matveychikov <[email protected]> wrote:
> 
> Early check for mount permissions prevents possible allocation of 3
> pages from kmalloc() pool by unpriveledged user which can be used for
> spraying the kernel heap.
> 
> Signed-off-by: Ilya V. Matveychikov <[email protected]>
> ---
> fs/namespace.c | 3 +++
> 1 file changed, 3 insertions(+)
> 
> diff --git a/fs/namespace.c b/fs/namespace.c
> index 5f75969adff1..1ef8feb2de2a 100644
> --- a/fs/namespace.c
> +++ b/fs/namespace.c
> @@ -3046,6 +3046,9 @@ int ksys_mount(char __user *dev_name, char __user 
> *dir_name, char __user *type,
>       char *kernel_dev;
>       void *options;
> 
> +     if (!may_mount())
> +             return -EPERM;
> +
>       kernel_type = copy_mount_string(type);
>       ret = PTR_ERR(kernel_type);
>       if (IS_ERR(kernel_type))
> --
> 2.17.0
> 

Reply via email to