cvs commit: src/sys/kern vfs_cache.c

[David O'Brien]

On Fri, Jun 17, 2005 at 01:05:13AM +0000, Jeff Roberson wrote:
>   Log:
>    - Fix a leaked reference to a vnode via v_dd.  We rely on cache_purge() and
>      cache_zap() to clear the v_dd pointers when a directory vnode is forcibly
>      discarded.  For this to work, all vnodes with v_dd pointers to a directory
>      must also have name cache entries linked via v_cache_dst to that dvp
>      otherwise we could not find them at cache_purge() time.  The following
>      code snipit could break this guarantee by unlinking a directory before
>      fetching it's dotdot.  The dotdot lookup would initialize the v_dd field
>      of the unlinked directory which could never be cleared.  To fix this
>      we don't initialize v_dd for orphaned vnodes.
>           printf("rmdir: %d\n", rmdir("../foo")); /* foo is cwd */
>           printf("chdir: %d\n", chdir(".."));
>           printf("%s\n", getwd(NULL));
>
>   Discovered by:  kkenn

Isn't this the same bug Peter discovered back in April at USENIX (via
Kmail).  I thought this bug was fixed.
   
-- 
-- David  (obrien at FreeBSD.org)