NFS: remove page size checking code

Remove the page size checking code for a readdir decode.  This is now done
by decode_dirent with xdr_streams.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

3 files changed, 2 insertions, 198 deletions

diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
index 0210c752e743..82f026422424 100644
--- a/fs/nfs/nfs2xdr.c
+++ b/fs/nfs/nfs2xdr.c
@@ -423,9 +423,7 @@ nfs_xdr_readdirres(struct rpc_rqst *req, __be32 *p, void *dummy)
         struct page **page;
         size_t hdrlen;
         unsigned int pglen, recvd;
-        u32 len;
         int status, nr = 0;
-        __be32 *end, *entry, *kaddr;
 
         if ((status = ntohl(*p++)))
                 return nfs_stat_to_errno(status);
@@ -445,59 +443,7 @@ nfs_xdr_readdirres(struct rpc_rqst *req, __be32 *p, void *dummy)
         if (pglen > recvd)
                 pglen = recvd;
         page = rcvbuf->pages;
-        kaddr = p = kmap_atomic(*page, KM_USER0);
-        end = (__be32 *)((char *)p + pglen);
-        entry = p;
-
-        /* Make sure the packet actually has a value_follows and EOF entry */
-        if ((entry + 1) > end)
-                goto short_pkt;
-
-        for (; *p++; nr++) {
-                if (p + 2 > end)
-                        goto short_pkt;
-                p++; /* fileid */
-                len = ntohl(*p++);
-                p += XDR_QUADLEN(len) + 1;      /* name plus cookie */
-                if (len > NFS2_MAXNAMLEN) {
-                        dprintk("NFS: giant filename in readdir (len 0x%x)!\n",
-                                                len);
-                        goto err_unmap;
-                }
-                if (p + 2 > end)
-                        goto short_pkt;
-                entry = p;
-        }
-
-        /*
-         * Apparently some server sends responses that are a valid size, but
-         * contain no entries, and have value_follows==0 and EOF==0. For
-         * those, just set the EOF marker.
-         */
-        if (!nr && entry[1] == 0) {
-                dprintk("NFS: readdir reply truncated!\n");
-                entry[1] = 1;
-        }
- out:
-        kunmap_atomic(kaddr, KM_USER0);
         return nr;
- short_pkt:
-        /*
-         * When we get a short packet there are 2 possibilities. We can
-         * return an error, or fix up the response to look like a valid
-         * response and return what we have so far. If there are no
-         * entries and the packet was short, then return -EIO. If there
-         * are valid entries in the response, return them and pretend that
-         * the call was successful, but incomplete. The caller can retry the
-         * readdir starting at the last cookie.
-         */
-        entry[0] = entry[1] = 0;
-        if (!nr)
-                nr = -errno_NFSERR_IO;
-        goto out;
-err_unmap:
-        nr = -errno_NFSERR_IO;
-        goto out;
 }
 
 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
diff --git a/fs/nfs/nfs3xdr.c b/fs/nfs/nfs3xdr.c
index d562c8d9d56e..dc98eb7976c3 100644
--- a/fs/nfs/nfs3xdr.c
+++ b/fs/nfs/nfs3xdr.c
@@ -554,9 +554,8 @@ nfs3_xdr_readdirres(struct rpc_rqst *req, __be32 *p, struct nfs3_readdirres *res
         struct kvec *iov = rcvbuf->head;
         struct page **page;
         size_t hdrlen;
-        u32 len, recvd, pglen;
+        u32 recvd, pglen;
         int status, nr = 0;
-        __be32 *entry, *end, *kaddr;
 
         status = ntohl(*p++);
         /* Decode post_op_attrs */
@@ -586,83 +585,8 @@ nfs3_xdr_readdirres(struct rpc_rqst *req, __be32 *p, struct nfs3_readdirres *res
         if (pglen > recvd)
                 pglen = recvd;
         page = rcvbuf->pages;
-        kaddr = p = kmap_atomic(*page, KM_USER0);
-        end = (__be32 *)((char *)p + pglen);
-        entry = p;
-
-        /* Make sure the packet actually has a value_follows and EOF entry */
-        if ((entry + 1) > end)
-                goto short_pkt;
-
-        for (; *p++; nr++) {
-                if (p + 3 > end)
-                        goto short_pkt;
-                p += 2;                         /* inode # */
-                len = ntohl(*p++);              /* string length */
-                p += XDR_QUADLEN(len) + 2;      /* name + cookie */
-                if (len > NFS3_MAXNAMLEN) {
-                        dprintk("NFS: giant filename in readdir (len 0x%x)!\n",
-                                                len);
-                        goto err_unmap;
-                }
-
-                if (res->plus) {
-                        /* post_op_attr */
-                        if (p + 2 > end)
-                                goto short_pkt;
-                        if (*p++) {
-                                p += 21;
-                                if (p + 1 > end)
-                                        goto short_pkt;
-                        }
-                        /* post_op_fh3 */
-                        if (*p++) {
-                                if (p + 1 > end)
-                                        goto short_pkt;
-                                len = ntohl(*p++);
-                                if (len > NFS3_FHSIZE) {
-                                        dprintk("NFS: giant filehandle in "
-                                                "readdir (len 0x%x)!\n", len);
-                                        goto err_unmap;
-                                }
-                                p += XDR_QUADLEN(len);
-                        }
-                }
-
-                if (p + 2 > end)
-                        goto short_pkt;
-                entry = p;
-        }
 
-        /*
-         * Apparently some server sends responses that are a valid size, but
-         * contain no entries, and have value_follows==0 and EOF==0. For
-         * those, just set the EOF marker.
-         */
-        if (!nr && entry[1] == 0) {
-                dprintk("NFS: readdir reply truncated!\n");
-                entry[1] = 1;
-        }
- out:
-        kunmap_atomic(kaddr, KM_USER0);
         return nr;
- short_pkt:
-        /*
-         * When we get a short packet there are 2 possibilities. We can
-         * return an error, or fix up the response to look like a valid
-         * response and return what we have so far. If there are no
-         * entries and the packet was short, then return -EIO. If there
-         * are valid entries in the response, return them and pretend that
-         * the call was successful, but incomplete. The caller can retry the
-         * readdir starting at the last cookie.
-         */
-        entry[0] = entry[1] = 0;
-        if (!nr)
-                nr = -errno_NFSERR_IO;
-        goto out;
-err_unmap:
-        nr = -errno_NFSERR_IO;
-        goto out;
 }
 
 __be32 *
diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c
index a4919e999354..8346e977d837 100644
--- a/fs/nfs/nfs4xdr.c
+++ b/fs/nfs/nfs4xdr.c
@@ -4200,12 +4200,9 @@ out_overflow:
 static int decode_readdir(struct xdr_stream *xdr, struct rpc_rqst *req, struct nfs4_readdir_res *readdir)
 {
         struct xdr_buf  *rcvbuf = &req->rq_rcv_buf;
-        struct page     *page = *rcvbuf->pages;
         struct kvec     *iov = rcvbuf->head;
         size_t          hdrlen;
         u32             recvd, pglen = rcvbuf->page_len;
-        __be32          *end, *entry, *p, *kaddr;
-        unsigned int    nr = 0;
         int             status;
 
         status = decode_op_hdr(xdr, OP_READDIR);
@@ -4225,71 +4222,8 @@ static int decode_readdir(struct xdr_stream *xdr, struct rpc_rqst *req, struct n
                 pglen = recvd;
         xdr_read_pages(xdr, pglen);
 
-        BUG_ON(pglen + readdir->pgbase > PAGE_CACHE_SIZE);
-        kaddr = p = kmap_atomic(page, KM_USER0);
-        end = p + ((pglen + readdir->pgbase) >> 2);
-        entry = p;
-
-        /* Make sure the packet actually has a value_follows and EOF entry */
-        if ((entry + 1) > end)
-                goto short_pkt;
-
-        for (; *p++; nr++) {
-                u32 len, attrlen, xlen;
-                if (end - p < 3)
-                        goto short_pkt;
-                dprintk("cookie = %Lu, ", *((unsigned long long *)p));
-                p += 2;                 /* cookie */
-                len = ntohl(*p++);      /* filename length */
-                if (len > NFS4_MAXNAMLEN) {
-                        dprintk("NFS: giant filename in readdir (len 0x%x)\n",
-                                        len);
-                        goto err_unmap;
-                }
-                xlen = XDR_QUADLEN(len);
-                if (end - p < xlen + 1)
-                        goto short_pkt;
-                dprintk("filename = %*s\n", len, (char *)p);
-                p += xlen;
-                len = ntohl(*p++);      /* bitmap length */
-                if (end - p < len + 1)
-                        goto short_pkt;
-                p += len;
-                attrlen = XDR_QUADLEN(ntohl(*p++));
-                if (end - p < attrlen + 2)
-                        goto short_pkt;
-                p += attrlen;           /* attributes */
-                entry = p;
-        }
-        /*
-         * Apparently some server sends responses that are a valid size, but
-         * contain no entries, and have value_follows==0 and EOF==0. For
-         * those, just set the EOF marker.
-         */
-        if (!nr && entry[1] == 0) {
-                dprintk("NFS: readdir reply truncated!\n");
-                entry[1] = 1;
-        }
-out:
-        kunmap_atomic(kaddr, KM_USER0);
+
         return 0;
-short_pkt:
-        /*
-         * When we get a short packet there are 2 possibilities. We can
-         * return an error, or fix up the response to look like a valid
-         * response and return what we have so far. If there are no
-         * entries and the packet was short, then return -EIO. If there
-         * are valid entries in the response, return them and pretend that
-         * the call was successful, but incomplete. The caller can retry the
-         * readdir starting at the last cookie.
-         */
-        dprintk("%s: short packet at entry %d\n", __func__, nr);
-        entry[0] = entry[1] = 0;
-        if (nr)
-                goto out;
-err_unmap:
-        kunmap_atomic(kaddr, KM_USER0);
-        return -errno_NFSERR_IO;
 }
 
 static int decode_readlink(struct xdr_stream *xdr, struct rpc_rqst *req)