nfs: fix the handling of replies to MKNOD and SYMLINK

The Linux NFS server does not accept a setting of file size to 0 for
sockets and FIFOs so there is code to strip that for those cases. I also
spotted that the file modification times were not being applied to a
created file so there is now just one rpc to set all file attributes using
xdr_encode_create_state(). This sets the times to be server time which is
appropriate for a new file (even though it was created in the previous RPC
call). The previous code was supplying the 'gid' based on that returned by
the 'stat' but I don't think that can be relied on since the V3 protocol
states that CREATE3 using EXCLUSIVE cannot guarantee any file attributes
until after the SETATTR3.

1 files changed, 30 insertions, 2 deletions

diff --git a/nfs/nfs.c b/nfs/nfs.c
index 313c1e4a..40e62669 100644
--- a/nfs/nfs.c
+++ b/nfs/nfs.c
@@ -25,6 +25,7 @@
 
 #include <string.h>
 #include <netinet/in.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <sys/sysmacros.h>
 
@@ -179,6 +180,30 @@ xdr_encode_string (int *p, const char *string)
   return xdr_encode_data (p, string, strlen (string));
 }
 
+/* Some NFSv3 rpcs can fail if the file size field
+   is set within the set attributes unnecessarily. */
+static inline bool
+nfs_sattr3_size_needed(mode_t mode, size_t sz)
+{
+  if (sz == 0)
+    {
+      switch (hurd_mode_to_nfs_type (mode))
+	{
+	case NFSOCK:
+	case NF3FIFO:
+	  /* NFCHR and NFBLK probaly also fall into this
+	     category but as unable to check then leave
+	     those alone. */
+	  return false;
+
+	default:
+	  break;
+	}
+    }
+
+  return true;
+}
+
 /* Encode a MODE into an otherwise empty sattr.  */
 int *
 xdr_encode_sattr_mode (int *p, mode_t mode)
@@ -372,14 +397,17 @@ xdr_encode_sattr_stat (int *p,
     }
   else
     {
+      bool needs_size = nfs_sattr3_size_needed (st->st_mode, st->st_size);
+
       *(p++) = htonl (1);		/* set mode */
       *(p++) = htonl (hurd_mode_to_nfs_mode (st->st_mode));
       *(p++) = htonl (1);		/* set uid */
       *(p++) = htonl (st->st_uid);
       *(p++) = htonl (1);		/* set gid */
       *(p++) = htonl (st->st_gid);
-      *(p++) = htonl (1);		/* set size */
-      p = xdr_encode_64bit (p, st->st_size);
+      *(p++) = htonl (needs_size);	/* set size */
+      if (needs_size)
+	p = xdr_encode_64bit (p, st->st_size);
       *(p++) = htonl (SET_TO_CLIENT_TIME); /* set atime */
       *(p++) = htonl (st->st_atim.tv_sec);
       *(p++) = htonl (st->st_atim.tv_nsec);