2014-08-04 21:37:32

by Scott Mayhew

Subject: [PATCH] nfs: reject changes to resvport and sharecache during remount

Commit c8e47028 made it possible to change resvport/noresvport and
sharecache/nosharecache via a remount operation, neither of which should be
allowed.

Signed-off-by: Scott Mayhew <[email protected]>
---
fs/nfs/super.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 084af10..3fd8332 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2180,7 +2180,7 @@ out_no_address:
return -EINVAL;
}

-#define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
+#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
| NFS_MOUNT_SECURE \
| NFS_MOUNT_TCP \
| NFS_MOUNT_VER3 \
@@ -2188,15 +2188,16 @@ out_no_address:
| NFS_MOUNT_NONLM \
| NFS_MOUNT_BROKEN_SUID \
| NFS_MOUNT_STRICTLOCK \
- | NFS_MOUNT_UNSHARED \
- | NFS_MOUNT_NORESVPORT \
| NFS_MOUNT_LEGACY_INTERFACE)

+#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
+ ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
+
static int
nfs_compare_remount_data(struct nfs_server *nfss,
struct nfs_parsed_mount_data *data)
{
- if ((data->flags ^ nfss->flags) & NFS_MOUNT_CMP_FLAGMASK ||
+ if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
data->rsize != nfss->rsize ||
data->wsize != nfss->wsize ||
data->version != nfss->nfs_client->rpc_ops->version ||
--
1.9.3

2014-08-05 13:52:03

by David Wysochanski

Subject: Re: [PATCH] nfs: reject changes to resvport and sharecache during remount

On Mon, 2014-08-04 at 17:37 -0400, Scott Mayhew wrote:
> Commit c8e47028 made it possible to change resvport/noresvport and
> sharecache/nosharecache via a remount operation, neither of which should be
> allowed.
>
> Signed-off-by: Scott Mayhew <[email protected]>
> ---
> fs/nfs/super.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
> index 084af10..3fd8332 100644
> --- a/fs/nfs/super.c
> +++ b/fs/nfs/super.c
> @@ -2180,7 +2180,7 @@ out_no_address:
> return -EINVAL;
> }
>
> -#define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
> +#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
> | NFS_MOUNT_SECURE \
> | NFS_MOUNT_TCP \
> | NFS_MOUNT_VER3 \
> @@ -2188,15 +2188,16 @@ out_no_address:
> | NFS_MOUNT_NONLM \
> | NFS_MOUNT_BROKEN_SUID \
> | NFS_MOUNT_STRICTLOCK \
> - | NFS_MOUNT_UNSHARED \
> - | NFS_MOUNT_NORESVPORT \
> | NFS_MOUNT_LEGACY_INTERFACE)
>
> +#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
> + ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
> +
> static int
> nfs_compare_remount_data(struct nfs_server *nfss,
> struct nfs_parsed_mount_data *data)
> {
> - if ((data->flags ^ nfss->flags) & NFS_MOUNT_CMP_FLAGMASK ||
> + if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
> data->rsize != nfss->rsize ||
> data->wsize != nfss->wsize ||
> data->version != nfss->nfs_client->rpc_ops->version ||

I reviewed this and it looks good to me.

Reviewed-by: Dave Wysochanski <[email protected]>