[linux-cifs-client] surprise behavior #1: ENOENT for existing directories

[aaron brick]

thank you guys very much for responding to my issues. i have now
remounted the share with noserverino. hopefully the problems will go
away and in a few days i can come back and tell you so.

cheers!
aaron.

--   aaron brick
--   aaron at lithic.org
--   http://www.lithic.org





2009/11/30 Jeff Layton <jlayton at samba.org>:
> On Mon, 30 Nov 2009 22:14:22 +0530
> Suresh Jayaraman <sjayaraman at suse.de> wrote:
>
>> On 11/30/2009 06:53 PM, Jeff Layton wrote:
>> > On Mon, 30 Nov 2009 16:45:59 +0530
>> > Suresh Jayaraman <sjayaraman at suse.de> wrote:
>> >
>> >> On 11/30/2009 07:46 AM, aaron brick wrote:
>> >>> i am having two intermittent problems with CIFS and am sending
>> >>> separate emails to the list for each. this paragraph is identical. my
>> >>> desktop runs debian and kernel 2.6.32rc7; i am mounting a filesystem
>> >>> from my synology NAS, running DSM 2.2-0942 and using ext3 & RAID5
>> >>> internally. the link is gigabit through cat5e and a netgear switch.
>> >>> the only CIFS dmesg entry i see is a couple of: "CIFS VFS: server
>> >>> 10.1.1.2 of type Samba 3.2.8 returned unexpected error on SMB posix
>> >>> open, disabling posix open support. Check if server update available."
>> >>> (FWIW, synology hasn't released a firmware with a more recent samba.)
>> >>>
>> >>>
>> >>> here, creating files within a directory sometimes fails with ENOENT as
>> >>> if the parent did not exist. this generally prevents me from using the
>> >>> shared filesystem for compilation. an example follows:
>> >>>
>> >>>
>> >>> 11:08 / > mount | grep nas
>> >>> //nas/data on /data type cifs (rw,mand)
>> >>> 11:08 / > cd data
>> >>> 11:08 /data > mkdir a
>> >>> 11:08 /data > mkdir a/b
>> >>> mkdir: cannot create directory `a/b': No such file or directory
>> >>> 11:08 /data > strace mkdir a/b |& grep mkdir
>> >>> execve("/bin/mkdir", ["mkdir", "a/b"], [/* 22 vars */]) = 0
>> >>> mkdir("a/b", 0777)                      = -1 ENOENT (No such file or directory)
>> >>> write(2, "mkdir: ", 7mkdir: )                  = 7
>> >>>
>> >>
>> >> I have not been able to reproduce this 2.6.31-rc1 against Samba 3.2.7. But a
>> >> quick look at the code suggests there could be a problem if we do this
>> >> sequence:
>> >>
>> >> POSIX open against Samba server < 3.3.1 (tcon->broken_posix_open will be set)
>> >> followed by a mkdir (will call CIFSPOSIXCreate). As we don't seem to check
>> >> whether the broken_posix_open is set, this might have led to this issue I think.
>> >>
>> >> Does the following patch (a quick, untested) fix the issue?
>> >>
>> >>
>> >>
>> >>  fs/cifs/inode.c |    3 ++-
>> >>  1 files changed, 2 insertions(+), 1 deletions(-)
>> >>
>> >> diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
>> >> index cababd8..f1e9ab6 100644
>> >> --- a/fs/cifs/inode.c
>> >> +++ b/fs/cifs/inode.c
>> >> @@ -1038,7 +1038,8 @@ int cifs_mkdir(struct inode *inode, struct dentry *direntry, int mode)
>> >>            return rc;
>> >>    }
>> >>
>> >> -  if ((pTcon->ses->capabilities & CAP_UNIX) &&
>> >> +  if (!tcon->broken_posix_open && tcon->unix_ext &&
>> >              ^^^^ should be "pTcon"
>> >
>>
>> Oops, sorry about the not even compile tested patch. Here is the
>> compile tested patch. Could you please test this one?
>>
>>
>>  fs/cifs/inode.c |    3 ++-
>>  1 files changed, 2 insertions(+), 1 deletions(-)
>>
>> diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
>> index cababd8..31be938 100644
>> --- a/fs/cifs/inode.c
>> +++ b/fs/cifs/inode.c
>> @@ -1038,7 +1038,8 @@ int cifs_mkdir(struct inode *inode, struct dentry *direntry, int mode)
>>               return rc;
>>       }
>>
>> -     if ((pTcon->ses->capabilities & CAP_UNIX) &&
>> +     if (!pTcon->broken_posix_open && pTcon->unix_ext &&
>> +         (pTcon->ses->capabilities & CAP_UNIX) &&
>>               (CIFS_UNIX_POSIX_PATH_OPS_CAP &
>>                       le64_to_cpu(pTcon->fsUnixInfo.Capability))) {
>>               u32 oplock = 0;
>
> Now that I think about it though...
>
> The whole broken_posix_open thing was not a problem for actual creates,
> just when opening existing files. I'm pretty sure we still want to use
> posix creates for mkdir even if broken_posix_open is set.
>
> I'm more interested to know whether both of these problems go away if
> he mounts with "noserverino".
>
> --
> Jeff Layton <jlayton at samba.org>
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