Re: 3.18.1: broken directory with one file too many

From: J. Bruce Fields
Date: Thu Dec 18 2014 - 12:19:00 EST


On Thu, Dec 18, 2014 at 10:19:14AM -0500, J. Bruce Fields wrote:
> On Thu, Dec 18, 2014 at 09:58:06AM -0500, Benjamin Coddington wrote:
> > Frame 36 of nfs-client.pcap has this interesting string:
> >
> > 0ff0 00 01 3b f6 fb b6 26 16 8f 7c 00 00 00 41 62 74 ..;...&..|...Abt
> > 1000 72 66 73 2d 32 30 00 00 00 00 00 00 00 00 30 36 rfs-20........06
> > 1010 2d 66 69 78 2d 64 65 61 64 6c 6f 63 6b 2d 77 68 -fix-deadlock-wh
> > 1020 65 6e 2d 6d 6f 75 6e 74 69 6e 67 2d 61 2d 64 65 en-mounting-a-de
> > 1030 67 72 61 64 65 64 2d 66 73 2e 70 61 74 63 68 00 graded-fs.patch.
>
> Yes, that looks like the server messing up the encoding of the reply.

And indeed looking at the git repo that matches up with the entry:

btrfs-20........06-fix-deadlock-when-mounting-a-degraded-fs.patch.
btrfs-20140619-006-fix-deadlock-when-mounting-a-degraded-fs.patch

So a stray 8 bytes of zeroes got written there.

And the reply also ends with 000000017fffffff when I believe it should
end with two 4-byte 0's (no value follows, not EOF).

So I think those 0's got written to the wrong offset. That should be
enough information to find the bug....

--b.
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