From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
According to RFC1813: "If count is 0, the WRITE will succeed
and return a count of 0, barring errors due to permissions checking."
Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx>
---
fs/nfsd/vfs.c | 3 +++
net/sunrpc/svc.c | 2 +-
2 files changed, 4 insertions(+), 1 deletion(-)
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 4d57befdac6e..38fdfcbb079e 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -969,6 +969,9 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf,
trace_nfsd_write_opened(rqstp, fhp, offset, *cnt);
+ if (!*cnt)
+ return nfs_ok;
+
if (sb->s_export_op)
exp_op_flags = sb->s_export_op->flags;
diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index a3bbe5ce4570..d1ccf37a4588 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1692,7 +1692,7 @@ unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, struct page **pages,
* entirely in rq_arg.pages. In this case, @first is empty.
*/
i = 0;
- if (first->iov_len) {
+ if (first->iov_len || !total) {
vec[i].iov_base = first->iov_base;
vec[i].iov_len = min_t(size_t, total, first->iov_len);
total -= vec[i].iov_len;
--
2.33.1
