svn commit: r229627 - stable/9/sys/fs/devfs

[John Baldwin]

Author: jhb
Date: Thu Jan  5 19:36:23 2012
New Revision: 229627
URL: http://svn.freebsd.org/changeset/base/229627

Log:
  MFC 228361:
  Explicitly use curthread while manipulating td_fpop during last close
  of a devfs file descriptor in devfs_close_f().  The passed in td argument
  may be NULL if the close was invoked by garbage collection of open
  file descriptors in pending control messages in the socket buffer of a
  UNIX domain socket after it was closed.

Modified:
  stable/9/sys/fs/devfs/devfs_vnops.c
Directory Properties:
  stable/9/sys/   (props changed)
  stable/9/sys/amd64/include/xen/   (props changed)
  stable/9/sys/boot/   (props changed)
  stable/9/sys/boot/i386/efi/   (props changed)
  stable/9/sys/boot/ia64/efi/   (props changed)
  stable/9/sys/boot/ia64/ski/   (props changed)
  stable/9/sys/boot/powerpc/boot1.chrp/   (props changed)
  stable/9/sys/boot/powerpc/ofw/   (props changed)
  stable/9/sys/cddl/contrib/opensolaris/   (props changed)
  stable/9/sys/conf/   (props changed)
  stable/9/sys/contrib/dev/acpica/   (props changed)
  stable/9/sys/contrib/octeon-sdk/   (props changed)
  stable/9/sys/contrib/pf/   (props changed)
  stable/9/sys/contrib/x86emu/   (props changed)

Modified: stable/9/sys/fs/devfs/devfs_vnops.c
==============================================================================
--- stable/9/sys/fs/devfs/devfs_vnops.c	Thu Jan  5 19:18:41 2012	(r229626)
+++ stable/9/sys/fs/devfs/devfs_vnops.c	Thu Jan  5 19:36:23 2012	(r229627)
@@ -600,10 +600,14 @@ devfs_close_f(struct file *fp, struct th
 	int error;
 	struct file *fpop;
 
-	fpop = td->td_fpop;
-	td->td_fpop = fp;
+	/*
+	 * NB: td may be NULL if this descriptor is closed due to
+	 * garbage collection from a closed UNIX domain socket.
+	 */
+	fpop = curthread->td_fpop;
+	curthread->td_fpop = fp;
 	error = vnops.fo_close(fp, td);
-	td->td_fpop = fpop;
+	curthread->td_fpop = fpop;
 
 	/*
 	 * The f_cdevpriv cannot be assigned non-NULL value while we