Re: [PATCH] nfsd: fix change_info in NFSv4 RENAME replies

[Chuck Lever III]

> On Sep 9, 2023, at 1:23 PM, Jeff Layton <jlayton@xxxxxxxxxx> wrote:
> 
> On Sat, 2023-09-09 at 11:18 -0400, Chuck Lever wrote:
>> On Sat, Sep 09, 2023 at 07:12:30AM -0400, Jeff Layton wrote:
>>> nfsd sends the transposed directory change info in the RENAME reply. The
>>> source directory is in save_fh and the target is in current_fh.
>>> 
>>> Reported-by: Zhi Li <yieli@xxxxxxxxxx>
>>> Reported-by: Benjamin Coddington <bcodding@xxxxxxxxxx>
>>> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
>>> ---
>>> This bug predates git, so I can't add a proper Fixes tag. I think this
>>> is probably appropriate for stable series kernels though.
>>> 
>>> This bug was largely papered over by the fact that we factored in the
>>> ctime when generating a change attribute. Since this commit, however:
>>> 
>>>    638e3e7d9493 nfsd: use the getattr operation to fetch i_version
>>> 
>>> We stopped doing that for directory inodes and that caused this bug to
>>> pop up.
>> 
>> Applied to nfsd-fixes with a "Cc: stable" tag added.
>> 
>> Is there a publicly-accessible bug report link that can be included?
>> 
>> 
> 
> Yes. I just made this one public:
> 
>    https://bugzilla.redhat.com/show_bug.cgi?id=2218844
> 
> It has Ben's reproducer script for this in it too.

Thanks, added in my private repo, to be pushed out later.


>>> ---
>>> fs/nfsd/nfs4proc.c | 4 ++--
>>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>> 
>>> diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
>>> index 5ca748309c26..4199ede0583c 100644
>>> --- a/fs/nfsd/nfs4proc.c
>>> +++ b/fs/nfsd/nfs4proc.c
>>> @@ -1058,8 +1058,8 @@ nfsd4_rename(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>>>      rename->rn_tname, rename->rn_tnamelen);
>>> if (status)
>>> return status;
>>> - set_change_info(&rename->rn_sinfo, &cstate->current_fh);
>>> - set_change_info(&rename->rn_tinfo, &cstate->save_fh);
>>> + set_change_info(&rename->rn_sinfo, &cstate->save_fh);
>>> + set_change_info(&rename->rn_tinfo, &cstate->current_fh);
>>> return nfs_ok;
>>> }
>>> 
>>> 
>>> ---
>>> base-commit: dd1386dd3c4f4bc55456c88180f9f39697bb95c0
>>> change-id: 20230908-nfsd-fixes-f5bdb87e6035
>>> 
>>> Best regards,
>>> -- 
>>> Jeff Layton <jlayton@xxxxxxxxxx>
>>> 
>> 
> 
> -- 
> Jeff Layton <jlayton@xxxxxxxxxx>


--
Chuck Lever