Re: NTFS directory read lockup
Joseph M. Malicki (malicki.1@osu.edu)
Mon, 18 Jan 1999 06:13:16 -0500
On Sun, 17 Jan 1999, Steve Dodd wrote:
>Hi,
>
>I have some more info - hope it is useful. My current way to induce the
>oops is to fire up netscape and read my JDK documentation which is on
>the NTFS partition for a bit, whilst running updatedb in the background.
>
>I added a bit of debug in and got this:
>
>kernel: root==NULL!! length=1024, walk->dir->vol=c000e044, walk->dir=c271d1a4, walk=c2829f28
>kernel: ntfs_read_attr called with buf=c2829ee4, buf->param=00000000
>kernel: Ack, r/w attr about to put with dest=c2829ee4, dest->size=56, dest->param=00000000, l=56
>kernel: Ick, ntfs_put called with dest->param NULL; dest=c2829ee4, src=c196e860, n=56
>kernel: memcpy called with null dest; src=c196e860, n=56
>kernel: Unable to handle kernel NULL pointer dereference at virtual address 00000000
>
>The problem is in ntfs_getdir:
>
>int ntfs_getdir(ntfs_iterate_s* walk)
>{
> int length=walk->dir->vol->mft_recordsize;
> int retval,error;
> /* start at the index root.*/
> char *root=ntfs_malloc(length);
> ntfs_io io;
>
> if( !root ) {
> printk( KERN_ERR "root==NULL!! length=%lu, walk->dir->vol=%p,"
> " walk->dir=%p, walk=%p\n", length, walk->dir->vol, walk->dir, walk );
> }
> io.fn_put=ntfs_put;
> io.param=root;
> io.size=length;
> error=ntfs_read_attr(walk->dir,walk->dir->vol->at_index_root,
> I30,0,&io);
> if(error)
>
>As you can see, ntfs_malloc seems to be returning null, even though it should
>only be trying to allocate 1024 bytes.. I'd thought maybe it was getting a
>nonsensically large value passed in there, but it seems not. Oh well, I'll
>carry on looking around..
>
>Cheers,
>Steve
Thanks!... I'll make a patch and submit it to Martin to check for a few
ntfs_malloc==NULL's... but since length is an int and its printing it as an %lu,
this could be a problem anyway...
But this brings to question whether kmalloc could have problems.
I'll try to look at that and see if i can figure out anything....
Joseph Malicki
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/