On Tue, 6 Apr 1999, Bill Studenmund wrote:

> Module Name:	src
> Committed By:	wrstuden
> Date:		Wed Apr  7 05:47:37 UTC 1999
> 
> Modified Files:
> 	src/sys/kern: vfs_lookup.c
> Log Message:
> Fix obscure bug in namei(), which was the cause of PR 7306.
> 
> The problem is that if "sl" is a symbolic link, a lookup on "sl/" will
> be flagged as the last component. Thus VOP_LOOKUP will lock the parent
> directory. But when lookup() exits, ni_pathlen will be greater than one,
> as "/" is left in the name, and namei() would not unlock the parent. The
> next call to lookup() to resolve the symbolic link would fail as the parent
> was still locked.

Forgot to mention the parent locking only happens with LOCKPARENT set. So
this bug only gets tickled when looking up a path with a symbolic link
followed only by trailing slashes AND LOCKPARENT set.

Take care,

Bill