Re: kern/40163: mv(1) cause WAPBL panic

[David Holland <dholland-bugs%netbsd.org@localhost>]

On Sat, Dec 13, 2008 at 02:55:02AM +0000, Greg Oster wrote:
 >>> Typing "mv foo/foo ." causes a panic if the filesystem in question has log
 >> ging enabled.
 >>  
 >>  I am able to reproduce this on 5.0 also, note that foo/foo must be a 
 >>  directory and not a regular file.
 >  
 >  Ah! That is the key..
 > [...]
 >  345             if (newparent) {
 >  346                     vn_lock(fdvp, LK_EXCLUSIVE | LK_RETRY);

Untested (I don't have any wapbl volumes on hand) patch:

Index: ufs_wapbl.c
===================================================================
RCS file: /cvsroot/src/sys/ufs/ufs/ufs_wapbl.c,v
retrieving revision 1.3
diff -u -p -r1.3 ufs_wapbl.c
--- ufs_wapbl.c 8 Dec 2008 11:37:37 -0000       1.3
+++ ufs_wapbl.c 13 Dec 2008 03:49:29 -0000
@@ -343,6 +343,11 @@ wapbl_ufs_rename(void *v)
        fcnp->cn_flags &= ~(MODMASK | SAVESTART);
        fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
        if (newparent) {
+               /* Check for the rename("foo/foo", "foo") case. */
+               if (fdvp == tvp) {
+                       error = doingdirectory ? ENOTEMPTY : ENOTDIR;
+                       goto out;
+               }
                vn_lock(fdvp, LK_EXCLUSIVE | LK_RETRY);
                if ((error = relookup(fdvp, &fvp, fcnp))) {
                        vput(fdvp);


Also, someone should squint at this to make sure "out" is the right
error exit path here.

-- 
David A. Holland
dholland%netbsd.org@localhost