>Number:         568
>Category:       kern
>Synopsis:       rename of one linked file onto its brother removes the target
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    gnats-admin (Kernel Bug People)
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Nov 11 12:35:03 1994
>Originator:     John Kohl
>Organization:
>Release:        1.0
>Environment:
System: NetBSD kolvir 1.0 NetBSD 1.0 (KOLVIR) #0: Thu Nov 10 20:10:51 EST 1994 jtk@kolvir:/u1/NetBSD-1.0/src/sys/arch/i386/compile/KOLVIR i386

>Description:
If you link two files, and do a rename("a", "b"), "a" is retained while
"b" is unlinked.  Whoops!

>How-To-Repeat:
% cd /tmp
% mkdir bar
% cd bar
% cp /etc/motd .
% ln motd xxx
% ls -lai
total 4
7 drwxr-xr-x  2 jtk   wheel  512 Nov 10 23:34 .
2 drwxrwxrwt  4 root  wheel  512 Nov 10 23:34 ..
8 -rw-r--r--  2 jtk   wheel   54 Nov 10 23:34 motd
8 -rw-r--r--  2 jtk   wheel   54 Nov 10 23:34 xxx
% mv motd xxx
% ls -lai
total 3
7 drwxr-xr-x  2 jtk   wheel  512 Nov 10 23:34 .
2 drwxrwxrwt  4 root  wheel  512 Nov 10 23:34 ..
8 -rw-r--r--  1 jtk   wheel   54 Nov 10 23:34 motd

>Fix:
	The short-circuit code in ufs_vnops.c:ufs_rename() which calls
to VOP_REMOVE() is short-circuiting the wrong entry.  A quick look
convinced me that I need to think carefully about locking/flags/etc
before touching this code.
>Audit-Trail:
>Unformatted: