NFS: Update MNT and MNT3 reply decoding functions

Solder xdr_stream-based XDR decoding functions into the in-kernel mountd
client that are more careful about checking data types and watching for
buffer overflows.  The new MNT3 decoder includes support for auth-flavor
list decoding.

The "_sz" macro for MNT3 replies was missing the size of the file handle.
I've added this back, and included the size of the auth flavor array.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 0207758..10cf111 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -83,6 +83,8 @@ struct nfs_mount_request {
        unsigned short          protocol;
        struct nfs_fh           *fh;
        int                     noresvport;
+       unsigned int            *auth_flav_len;
+       rpc_authflavor_t        *auth_flavs;
 };
 
 extern int nfs_mount(struct nfs_mount_request *info);

diff --git a/fs/nfs/mount_clnt.c b/fs/nfs/mount_clnt.c
index ed0a27e..618d815 100644 (file)
--- a/fs/nfs/mount_clnt.c
+++ b/fs/nfs/mount_clnt.c
@@ -39,6 +39,9 @@
  * XDR argument and result sizes
  */
 #define MNT_enc_dirpath_sz     encode_dirpath_sz
+#define MNT_dec_mountres_sz    (MNT_status_sz + MNT_fhandle_sz)
+#define MNT_dec_mountres3_sz   (MNT_status_sz + MNT_fhandle_sz + \
+                                MNT_authflav3_sz)
 
 /*
  * Defined by RFC 1094, section A.5
@@ -140,8 +143,10 @@ struct mnt_fhstatus {
  */
 int nfs_mount(struct nfs_mount_request *info)
 {
-       struct mnt_fhstatus     result = {
-               .fh             = info->fh
+       struct mountres result = {
+               .fh             = info->fh,
+               .auth_count     = info->auth_flav_len,
+               .auth_flavors   = info->auth_flavs,
        };
        struct rpc_message msg  = {
                .rpc_argp       = info->dirpath,
@@ -180,7 +185,7 @@ int nfs_mount(struct nfs_mount_request *info)
 
        if (status < 0)
                goto out_call_err;
-       if (result.status != 0)
+       if (result.errno != 0)
                goto out_mnt_err;
 
        dprintk("NFS: MNT request succeeded\n");
@@ -191,16 +196,16 @@ out:
 
 out_clnt_err:
        status = PTR_ERR(mnt_clnt);
-       dprintk("NFS: failed to create RPC client, status=%d\n", status);
+       dprintk("NFS: failed to create MNT RPC client, status=%d\n", status);
        goto out;
 
 out_call_err:
-       dprintk("NFS: failed to start MNT request, status=%d\n", status);
+       dprintk("NFS: MNT request failed, status=%d\n", status);
        goto out;
 
 out_mnt_err:
-       dprintk("NFS: MNT server returned result %d\n", result.status);
-       status = nfs_stat_to_errno(result.status);
+       dprintk("NFS: MNT server returned result %d\n", result.errno);
+       status = result.errno;
        goto out;
 }
 
@@ -291,6 +296,20 @@ static int decode_fhandle(struct xdr_stream *xdr, struct mountres *res)
        return 0;
 }
 
+static int mnt_dec_mountres(struct rpc_rqst *req, __be32 *p,
+                           struct mountres *res)
+{
+       struct xdr_stream xdr;
+       int status;
+
+       xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
+
+       status = decode_status(&xdr, res);
+       if (unlikely(status != 0 || res->errno != 0))
+               return status;
+       return decode_fhandle(&xdr, res);
+}
+
 static int decode_fhs_status(struct xdr_stream *xdr, struct mountres *res)
 {
        unsigned int i;
@@ -371,6 +390,25 @@ static int decode_auth_flavors(struct xdr_stream *xdr, struct mountres *res)
        return 0;
 }
 
+static int mnt_dec_mountres3(struct rpc_rqst *req, __be32 *p,
+                            struct mountres *res)
+{
+       struct xdr_stream xdr;
+       int status;
+
+       xdr_init_decode(&xdr, &req->rq_rcv_buf, p);
+
+       status = decode_fhs_status(&xdr, res);
+       if (unlikely(status != 0 || res->errno != 0))
+               return status;
+       status = decode_fhandle3(&xdr, res);
+       if (unlikely(status != 0)) {
+               res->errno = -EBADHANDLE;
+               return 0;
+       }
+       return decode_auth_flavors(&xdr, res);
+}
+
 static int xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p,
                                struct mnt_fhstatus *res)
 {
@@ -388,16 +426,13 @@ static int xdr_decode_fhstatus3(struct rpc_rqst *req, __be32 *p,
        return 0;
 }
 
-#define MNT_fhstatus_sz                (1 + 8)
-#define MNT_fhstatus3_sz       (1 + 16)
-
 static struct rpc_procinfo mnt_procedures[] = {
        [MOUNTPROC_MNT] = {
                .p_proc         = MOUNTPROC_MNT,
                .p_encode       = (kxdrproc_t)mnt_enc_dirpath,
-               .p_decode       = (kxdrproc_t) xdr_decode_fhstatus,
+               .p_decode       = (kxdrproc_t)mnt_dec_mountres,
                .p_arglen       = MNT_enc_dirpath_sz,
-               .p_replen       = MNT_fhstatus_sz,
+               .p_replen       = MNT_dec_mountres_sz,
                .p_statidx      = MOUNTPROC_MNT,
                .p_name         = "MOUNT",
        },
@@ -407,9 +442,9 @@ static struct rpc_procinfo mnt3_procedures[] = {
        [MOUNTPROC3_MNT] = {
                .p_proc         = MOUNTPROC3_MNT,
                .p_encode       = (kxdrproc_t)mnt_enc_dirpath,
-               .p_decode       = (kxdrproc_t) xdr_decode_fhstatus3,
+               .p_decode       = (kxdrproc_t)mnt_dec_mountres3,
                .p_arglen       = MNT_enc_dirpath_sz,
-               .p_replen       = MNT_fhstatus3_sz,
+               .p_replen       = MNT_dec_mountres3_sz,
                .p_statidx      = MOUNTPROC3_MNT,
                .p_name         = "MOUNT",
        },

diff --git a/fs/nfs/nfsroot.c b/fs/nfs/nfsroot.c
index 24c1b93..8c55b27 100644 (file)
--- a/fs/nfs/nfsroot.c
+++ b/fs/nfs/nfsroot.c
@@ -490,6 +490,7 @@ static int __init root_nfs_get_handle(void)
 {
        struct nfs_fh fh;
        struct sockaddr_in sin;
+       unsigned int auth_flav_len = 0;
        struct nfs_mount_request request = {
                .sap            = (struct sockaddr *)&sin,
                .salen          = sizeof(sin),
@@ -499,6 +500,7 @@ static int __init root_nfs_get_handle(void)
                .protocol       = (nfs_data.flags & NFS_MOUNT_TCP) ?
                                        XPRT_TRANSPORT_TCP : XPRT_TRANSPORT_UDP,
                .fh             = &fh,
+               .auth_flav_len  = &auth_flav_len,
        };
        int status;
 

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 539a61a..0b72357 100644 (file)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1380,6 +1380,7 @@ out_security_failure:
 static int nfs_try_mount(struct nfs_parsed_mount_data *args,
                         struct nfs_fh *root_fh)
 {
+       unsigned int auth_flavor_len = 0;
        struct nfs_mount_request request = {
                .sap            = (struct sockaddr *)
                                                &args->mount_server.address,
@@ -1387,6 +1388,7 @@ static int nfs_try_mount(struct nfs_parsed_mount_data *args,
                .protocol       = args->mount_server.protocol,
                .fh             = root_fh,
                .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
+               .auth_flav_len  = &auth_flavor_len,
        };
        int status;