aboutsummaryrefslogtreecommitdiff
path: root/fs/nfsd/nfs3xdr.c
diff options
context:
space:
mode:
Diffstat (limited to 'fs/nfsd/nfs3xdr.c')
-rw-r--r--fs/nfsd/nfs3xdr.c48
1 files changed, 38 insertions, 10 deletions
diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index 7e4bb0af24d..43fb360784b 100644
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -369,7 +369,7 @@ int
nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p,
struct nfsd3_writeargs *args)
{
- unsigned int len, v, hdr;
+ unsigned int len, v, hdr, dlen;
u32 max_blocksize = svc_max_payload(rqstp);
if (!(p = decode_fh(p, &args->fh))
@@ -379,18 +379,47 @@ nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p,
args->count = ntohl(*p++);
args->stable = ntohl(*p++);
len = args->len = ntohl(*p++);
+ /*
+ * The count must equal the amount of data passed.
+ */
+ if (args->count != args->len)
+ return 0;
+ /*
+ * Check to make sure that we got the right number of
+ * bytes.
+ *
+ * If more than one page was used, then compute the length
+ * of the data in the request as the total size of the
+ * request minus the transport protocol headers minus the
+ * RPC protocol headers minus the NFS protocol fields
+ * already consumed. If the request fits into a single
+ * page, then compete the length of the data as the size
+ * of the NFS portion of the request minus the NFS
+ * protocol fields already consumed.
+ */
hdr = (void*)p - rqstp->rq_arg.head[0].iov_base;
- if (rqstp->rq_arg.len < hdr ||
- rqstp->rq_arg.len - hdr < len)
+ if (rqstp->rq_respages != rqstp->rq_pages + 1) {
+ dlen = rqstp->rq_arg.len -
+ (PAGE_SIZE - rqstp->rq_arg.head[0].iov_len) - hdr;
+ } else {
+ dlen = rqstp->rq_arg.head[0].iov_len - hdr;
+ }
+ /*
+ * Round the length of the data which was specified up to
+ * the next multiple of XDR units and then compare that
+ * against the length which was actually received.
+ */
+ if (dlen != ((len + 3) & ~0x3))
return 0;
+ if (args->count > max_blocksize) {
+ args->count = max_blocksize;
+ len = args->len = max_blocksize;
+ }
rqstp->rq_vec[0].iov_base = (void*)p;
rqstp->rq_vec[0].iov_len = rqstp->rq_arg.head[0].iov_len - hdr;
-
- if (len > max_blocksize)
- len = max_blocksize;
- v= 0;
+ v = 0;
while (len > rqstp->rq_vec[v].iov_len) {
len -= rqstp->rq_vec[v].iov_len;
v++;
@@ -398,9 +427,8 @@ nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p,
rqstp->rq_vec[v].iov_len = PAGE_SIZE;
}
rqstp->rq_vec[v].iov_len = len;
- args->vlen = v+1;
-
- return args->count == args->len && rqstp->rq_vec[0].iov_len > 0;
+ args->vlen = v + 1;
+ return 1;
}
int