On 08/29/2013 03:30 PM, J. Bruce Fields wrote: > On Thu, Aug 29, 2013 at 11:57:45AM +0200, richard -rw- weinberger wrote: >> On Wed, Aug 28, 2013 at 7:21 PM, Toralf Förster <toralf.foerster@xxxxxx> wrote: >>> On 08/27/2013 08:06 PM, J. Bruce Fields wrote: >>>> On Tue, Aug 13, 2013 at 05:53:14PM -0400, bfields wrote: >>>>> On Mon, Aug 12, 2013 at 04:36:40PM +0200, Jan Kara wrote: >>>>>> On Sun 11-08-13 11:48:49, Toralf Förster wrote: >>>>>>> so that the server either crashes (if it is a user mode linux image) or at least its reboot functionality got broken >>>>>>> - if the NFS server is hammered with scary NFS calls using a fuzzy tool running at a remote NFS client under a non-privileged user id. >>>>>>> >>>>>>> It can re reproduced, if >>>>>>> - the NFS share is an EXT3 or EXT4 directory >>>>>>> - and it is created at file located at tempfs and mounted via loop device >>>>>>> - and the NFS server is forced to umount the NFS share >>>>>>> - and the server forced to restart the NSF service afterwards >>>>>>> - and trinity is used >>>>>>> >>>>>>> I could find a scenario for an automated bisect. 2 times it brought this commit >>>>>>> commit 68a3396178e6688ad7367202cdf0af8ed03c8727 >>>>>>> Author: J. Bruce Fields <bfields@xxxxxxxxxx> >>>>>>> Date: Thu Mar 21 11:21:50 2013 -0400 >>>>>>> >>>>>>> nfsd4: shut down more of delegation earlier >>>>> >>>>> Thanks for the report. I think I see the problem--after this commit >>>>> nfs4_set_delegation() failures result in nfs4_put_delegation being >>>>> called, but nfs4_put_delegation doesn't free the nfs4_file that has >>>>> already been set by alloc_init_deleg(). >>>>> >>>>> Let me think about how to fix that.... >>>> >>>> Sorry for the slow response--can you check whether this fixes the >>>> problem? >>>> >>> Yes. >>> >>> With the attached patch the problem can't be reproduced any longer with >>> the prepared test case and current git kernels. >> >> BTW: Is nobody else fuzz testing NFS? > > I don't know. Toralf's reports are the only ones I recall off the top > of my head, but I may have forgotten others. > well, 7255e71 and 3c50ba8 I'd say. >> Or are these bugs just more likely to hit on UML? This definitely not. I observed at a real system EXT4 corruptions/ issues but reported them to the EXT4 mailing list. It just took me a longer time to figure out a reliable configuration with 2 UML machiens to automatic bisect it. > That's also possible. > >> This is not the first NFS issue found by Toralf using UML and Trinity. > > Yep. The testing is definitely appreciated. Thx - in the mean while although my UML bisect scripts are working fine and trinity is stable enough even in UML environments to be trust worth. > > --b. > -- MfG/Sincerely Toralf Förster pgp finger print: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 7DB6 9DA3 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
