Am Freitag, den 10.11.2017, 16:03 +0100 schrieb Lucas Stach:
> Since bd8b2441742b (NFS: Store the raw NFS access mask in the inode's
> access cache) the mask already contains the NFS access bits, so it is
> wrong to try to map them from the MAY_* bits to the NFS_MAY_* bits
> in _nfs4_proc_access(). This leads to bogus access permissions being
> returned from the server.
>
> Fix this by using the mask directly, but be careful to not ask for
> to broad permissions from the calling nfs_do_access().
>
> CC: sta...@vger.kernel.org #4.13+
> Signed-off-by: Lucas Stach <l.st...@pengutronix.de>
> Tested-by: Björn Lässig <b.laes...@pengutronix.de>
This patch is incomplete, as it misses the NFSv3 parts. Please ignore
this patch.
Regards,
Lucas
> ---
> fs/nfs/dir.c | 8 ++++++--
> fs/nfs/nfs4proc.c | 19 +------------------
> 2 files changed, 7 insertions(+), 20 deletions(-)
>
> diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
> index 5ceaeb1f6fb6..dd3a06353bdc 100644
> --- a/fs/nfs/dir.c
> +++ b/fs/nfs/dir.c
> @@ -2426,8 +2426,12 @@ static int nfs_do_access(struct inode *inode,
> struct rpc_cred *cred, int mask)
> goto out;
>
> /* Be clever: ask server to check for all possible rights */
> - cache.mask = NFS_MAY_LOOKUP | NFS_MAY_EXECUTE
> - | NFS_MAY_WRITE | NFS_MAY_READ;
> + cache.mask = NFS_MAY_READ;
> + if (S_ISDIR(inode->i_mode))
> + cache.mask |= NFS_DIR_MAY_WRITE | NFS_MAY_LOOKUP;
> + else
> + cache.mask |= NFS_FILE_MAY_WRITE | NFS_MAY_EXECUTE;
> +
> cache.cred = cred;
> status = NFS_PROTO(inode)->access(inode, &cache);
> if (status != 0) {
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index 6c61e2b99635..cb7b5aafaef6 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -3889,6 +3889,7 @@ static int _nfs4_proc_access(struct inode
> *inode, struct nfs_access_entry *entry
> struct nfs4_accessargs args = {
> .fh = NFS_FH(inode),
> .bitmask = server->cache_consistency_bitmask,
> + .access = entry->mask,
> };
> struct nfs4_accessres res = {
> .server = server,
> @@ -3899,26 +3900,8 @@ static int _nfs4_proc_access(struct inode
> *inode, struct nfs_access_entry *entry
> .rpc_resp = &res,
> .rpc_cred = entry->cred,
> };
> - int mode = entry->mask;
> int status = 0;
>
> - /*
> - * Determine which access bits we want to ask for...
> - */
> - if (mode & MAY_READ)
> - args.access |= NFS4_ACCESS_READ;
> - if (S_ISDIR(inode->i_mode)) {
> - if (mode & MAY_WRITE)
> - args.access |= NFS4_ACCESS_MODIFY |
> NFS4_ACCESS_EXTEND | NFS4_ACCESS_DELETE;
> - if (mode & MAY_EXEC)
> - args.access |= NFS4_ACCESS_LOOKUP;
> - } else {
> - if (mode & MAY_WRITE)
> - args.access |= NFS4_ACCESS_MODIFY |
> NFS4_ACCESS_EXTEND;
> - if (mode & MAY_EXEC)
> - args.access |= NFS4_ACCESS_EXECUTE;
> - }
> -
> res.fattr = nfs_alloc_fattr();
> if (res.fattr == NULL)
> return -ENOMEM;
