net/9p: set error to EREMOTEIO if trans->write returns zero

If trans->write returns 0, p9_write_work goes through the error path, but
sets the error code to zero.

This patch sets the error code to EREMOTEIO if trans->write returns zero
value.

Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/net/9p/mux.c b/net/9p/mux.c
index c3aa87bc8b97..acb038810f39 100644
--- a/net/9p/mux.c
+++ b/net/9p/mux.c
@@ -505,8 +505,12 @@ again:
                 return;
         }
 
-        if (err <= 0)
+        if (err < 0)
+                goto error;
+        else if (err == 0) {
+                err = -EREMOTEIO;
                 goto error;
+        }
 
         m->wpos += err;
         if (m->wpos == m->wsize)