svn commit: r199137 - head/sys/kern

[Konstantin Belousov]

Author: kib
Date: Tue Nov 10 11:50:37 2009
New Revision: 199137
URL: http://svn.freebsd.org/changeset/base/199137

Log:
  When rename("a", "b/.") is performed, target namei() call returns
  dvp == vp. Rename syscall does not check for the case, and at least
  ufs_rename() cannot deal with it. POSIX explicitely requires that both
  rename(2) and rmdir(2) return EINVAL when any of the pathes end in "/.".
  
  Detect the slashdot lookup for RENAME or REMOVE in lookup(), and return
  EINVAL.
  
  Reported by:	Jim Meyering <jim meyering net>
  Tested by:	simon, pho
  MFC after:	1 week

Modified:
  head/sys/kern/vfs_lookup.c

Modified: head/sys/kern/vfs_lookup.c
==============================================================================
--- head/sys/kern/vfs_lookup.c	Tue Nov 10 11:46:53 2009	(r199136)
+++ head/sys/kern/vfs_lookup.c	Tue Nov 10 11:50:37 2009	(r199137)
@@ -552,6 +552,12 @@ dirloop:
 	else
 		cnp->cn_flags &= ~ISLASTCN;
 
+	if ((cnp->cn_flags & ISLASTCN) != 0 &&
+	    cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.' &&
+	    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
+		error = EINVAL;
+		goto bad;
+	}
 
 	/*
 	 * Check for degenerate name (e.g. / or "")