svn commit: r229016 - stable/9/sys/kern

[Konstantin Belousov]

Author: kib
Date: Fri Dec 30 19:58:06 2011
New Revision: 229016
URL: http://svn.freebsd.org/changeset/base/229016

Log:
  MFC r228178:
  If alloc_unr() call in the pipe_create() failed, then pipe->pipe_ino is
  -1. But, because ino_t is unsigned, this case was not covered by the
  test ino > 0 in pipeclose(), leading to the free_unr(-1). Fix it by
  explicitely comparing with 0 and -1.
  
  Do no access freed memory, the inode number was cached to prevent access
  to cpipe after it possibly was freed, but I failed to commit the right
  patch.

Modified:
  stable/9/sys/kern/sys_pipe.c
Directory Properties:
  stable/9/sys/   (props changed)

Modified: stable/9/sys/kern/sys_pipe.c
==============================================================================
--- stable/9/sys/kern/sys_pipe.c	Fri Dec 30 19:24:53 2011	(r229015)
+++ stable/9/sys/kern/sys_pipe.c	Fri Dec 30 19:58:06 2011	(r229016)
@@ -1554,8 +1554,8 @@ pipeclose(cpipe)
 	} else
 		PIPE_UNLOCK(cpipe);
 
-	if (ino > 0)
-		free_unr(pipeino_unr, cpipe->pipe_ino);
+	if (ino != 0 && ino != (ino_t)-1)
+		free_unr(pipeino_unr, ino);
 }
 
 /*ARGSUSED*/