Merge tag 'nfs-for-5.0-3' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client fixes from Anna Schumaker:
 "This addresses two bugs, one in the error code handling of
  nfs_page_async_flush() and one to fix a potential NULL pointer
  dereference in nfs_parse_devname().

  Stable bugfix:
   - Fix up return value on fatal errors in nfs_page_async_flush()

  Other bugfix:
   - Fix NULL pointer dereference of dev_name"

* tag 'nfs-for-5.0-3' of git://git.linux-nfs.org/projects/anna/linux-nfs:
  NFS: Fix up return value on fatal errors in nfs_page_async_flush()
  nfs: Fix NULL pointer dereference of dev_name

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 22ce3c8a2f463dd64dfba9877baa9071f3e63e22..0570391eaa165cf306d6ec4b31379acfa807b0fb 100644 (file)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1895,6 +1895,11 @@ static int nfs_parse_devname(const char *dev_name,
        size_t len;
        char *end;
 
+       if (unlikely(!dev_name || !*dev_name)) {
+               dfprintk(MOUNT, "NFS: device name not specified\n");
+               return -EINVAL;
+       }
+
        /* Is the host name protected with square brakcets? */
        if (*dev_name == '[') {
                end = strchr(++dev_name, ']');

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 5a0bbf917a32d45935122f8480d5492b9c65999f..f12cb31a41e5ba5bb1b0bbc7d710cecb11cf4e69 100644 (file)
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -621,11 +621,12 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
        nfs_set_page_writeback(page);
        WARN_ON_ONCE(test_bit(PG_CLEAN, &req->wb_flags));
 
-       ret = 0;
+       ret = req->wb_context->error;
        /* If there is a fatal error that covers this write, just exit */
-       if (nfs_error_is_fatal_on_server(req->wb_context->error))
+       if (nfs_error_is_fatal_on_server(ret))
                goto out_launder;
 
+       ret = 0;
        if (!nfs_pageio_add_request(pgio, req)) {
                ret = pgio->pg_error;
                /*
@@ -635,9 +636,9 @@ static int nfs_page_async_flush(struct nfs_pageio_descriptor *pgio,
                        nfs_context_set_write_error(req->wb_context, ret);
                        if (nfs_error_is_fatal_on_server(ret))
                                goto out_launder;
-               }
+               } else
+                       ret = -EAGAIN;
                nfs_redirty_request(req);
-               ret = -EAGAIN;
        } else
                nfs_add_stats(page_file_mapping(page)->host,
                                NFSIOS_WRITEPAGES, 1);