From: Luis Henriques <lhenriques@suse.de>
To: Jeff Layton <jlayton@kernel.org>
Cc: ceph-devel@vger.kernel.org, idryomov@gmail.com
Subject: Re: [PATCH] ceph: fix inode leak on getattr error in __fh_to_dentry
Date: Wed, 31 Mar 2021 10:53:24 +0100 [thread overview]
Message-ID: <YGRGlH/INmTuV2uw@suse.de> (raw)
In-Reply-To: <c434172e4d53cdbb1414eee1c22408996e10a3ed.camel@kernel.org>
On Tue, Mar 30, 2021 at 12:53:51PM -0400, Jeff Layton wrote:
> On Tue, 2021-03-30 at 14:46 +0100, Luis Henriques wrote:
> > On Fri, Mar 26, 2021 at 11:40:32AM -0400, Jeff Layton wrote:
> > > Cc: Luis Henriques <lhenriques@suse.de>
> > > Fixes: 878dabb64117 (ceph: don't return -ESTALE if there's still an open file)
> > > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > > ---
> > > fs/ceph/export.c | 4 +++-
> > > 1 file changed, 3 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/fs/ceph/export.c b/fs/ceph/export.c
> > > index f22156ee7306..17d8c8f4ec89 100644
> > > --- a/fs/ceph/export.c
> > > +++ b/fs/ceph/export.c
> > > @@ -178,8 +178,10 @@ static struct dentry *__fh_to_dentry(struct super_block *sb, u64 ino)
> > > return ERR_CAST(inode);
> > > /* We need LINK caps to reliably check i_nlink */
> > > err = ceph_do_getattr(inode, CEPH_CAP_LINK_SHARED, false);
> > > - if (err)
> > > + if (err) {
> > > + iput(inode);
> >
> > To be honest, I'm failing to see where we could be leaking the inode here.
> > We're trying to get LINK caps to do the check bellow; if ceph_do_getattr()
> > fails, the inode reference it (may) grabs will be released by calling
> > ceph_mdsc_put_request().
> >
> > Do you see any other possibility?
> >
>
> We already hold a reference to the inode at this point by virtue of the
> successful return from __lookup_inode. ceph_do_getattr does not consume
> that reference on success or failure, AFAICT.
Doh! Of course. I was looking at it the wrong way.
Cheers,
--
Luís
prev parent reply other threads:[~2021-03-31 9:52 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-26 15:40 [PATCH] ceph: fix inode leak on getattr error in __fh_to_dentry Jeff Layton
2021-03-29 3:10 ` Xiubo Li
2021-03-30 13:46 ` Luis Henriques
2021-03-30 16:53 ` Jeff Layton
2021-03-31 9:53 ` Luis Henriques [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YGRGlH/INmTuV2uw@suse.de \
--to=lhenriques@suse.de \
--cc=ceph-devel@vger.kernel.org \
--cc=idryomov@gmail.com \
--cc=jlayton@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).