From patchwork Fri Aug 23 18:14:03 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Snitzer X-Patchwork-Id: 13775671 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 14FEE42A9F; Fri, 23 Aug 2024 18:14:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724436872; cv=none; b=ChY7XXd9SMZ+Beg6sZQBizERb54HNJreor6pSl+OAc2jikhqvr+RaH9iYpkZVfGLgNVks6IYrI47bBo6GQhT5xdjt572ZttMqTx0gNxM2nhnWXCSpzzBcPc5FunsVrMPpUvwaOgduWWRtgczxhj3xiDK0q0FK/ncFDIc/Tz+jWs= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724436872; c=relaxed/simple; bh=/PcrXWFBH/a9oVLTwSi44yoG+kIq935PZYihsXOQbyY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=baciA0qDi9BoUOIOoLiBBvR4T9vztV1mFWmsKWjrh0YdkcAOXk+314Om+L7Z4LhvMqzpj/jBn/J/EIkNvvolbyL//Gwp4kbVKyN4P4pEXwaqakAZOVT6McAwh8FoyegkiJhLU0Hdvx71zFFIAri0VXflw82XPcBkA4jmiHA6gkU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RJNmPk9C; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RJNmPk9C" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B7439C4AF0F; Fri, 23 Aug 2024 18:14:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724436871; bh=/PcrXWFBH/a9oVLTwSi44yoG+kIq935PZYihsXOQbyY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RJNmPk9CFD18cqbQrq1d2g92g/k4RhC9uB2T0X63KKPuPeod+TzFDTXmLbHtODv4B 85OO2HlpD2wn1O+Y4PSA0FbiL1h0aRmlAk5Xn1Z9Sl8J4kHXRQYq+xVXYIOhFywqvT QeG3lmUe2INJ9u443m9T59YGyqE5U/UA4sKpeseoSjFiNG4GMAUs6Hc4TN8jq0//Ba g4qI9yq4Wzp6zwYfJwdpj+RGNqaRBTNSb5ukuBwN7BCO94DgsEDKw5ny29uSVDLfFc SMMdCcsAdsgpGODTCRqK/94wmQtYqU4yC5C+8Km9vL2dRHg73PnfMKhhmIIvCHF+Z+ 08r6l46JcaG5Q== From: Mike Snitzer To: linux-nfs@vger.kernel.org Cc: Jeff Layton , Chuck Lever , Anna Schumaker , Trond Myklebust , NeilBrown , linux-fsdevel@vger.kernel.org Subject: [PATCH v13 05/19] nfsd: add nfsd_file_acquire_local() Date: Fri, 23 Aug 2024 14:14:03 -0400 Message-ID: <20240823181423.20458-6-snitzer@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240823181423.20458-1-snitzer@kernel.org> References: <20240823181423.20458-1-snitzer@kernel.org> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: NeilBrown nfsd_file_acquire_local() can be used to look up a file by filehandle without having a struct svc_rqst. This can be used by NFS LOCALIO to allow the NFS client to bypass the NFS protocol to directly access a file provided by the NFS server which is running in the same kernel. In nfsd_file_do_acquire() care is taken to always use fh_verify() if rqstp is not NULL (as is the case for non-LOCALIO callers). Otherwise the non-LOCALIO callers will not supply the correct and required arguments to __fh_verify (e.g. nfs_vers is 0, gssclient isn't passed). Also, use GC for nfsd_file returned by nfsd_file_acquire_local. GC offers performance improvements if/when a file is reopened before launderette cleans it from the filecache's LRU. Suggested-by: Jeff Layton # use filecache's GC Signed-off-by: NeilBrown Co-developed-by: Mike Snitzer Signed-off-by: Mike Snitzer --- fs/nfsd/filecache.c | 63 ++++++++++++++++++++++++++++++++++++++++----- fs/nfsd/filecache.h | 4 +++ fs/nfsd/nfsfh.c | 2 +- fs/nfsd/nfsfh.h | 5 ++++ 4 files changed, 66 insertions(+), 8 deletions(-) diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index 9e9d246f993c..94ecb9ed0ed1 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -982,12 +982,14 @@ nfsd_file_is_cached(struct inode *inode) } static __be32 -nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, +nfsd_file_do_acquire(struct svc_rqst *rqstp, struct net *net, + struct svc_cred *cred, int nfs_vers, + struct auth_domain *client, + struct svc_fh *fhp, unsigned int may_flags, struct file *file, struct nfsd_file **pnf, bool want_gc) { unsigned char need = may_flags & NFSD_FILE_MAY_MASK; - struct net *net = SVC_NET(rqstp); struct nfsd_file *new, *nf; bool stale_retry = true; bool open_retry = true; @@ -996,8 +998,13 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, int ret; retry: - status = fh_verify(rqstp, fhp, S_IFREG, - may_flags|NFSD_MAY_OWNER_OVERRIDE); + if (rqstp) { + status = fh_verify(rqstp, fhp, S_IFREG, + may_flags|NFSD_MAY_OWNER_OVERRIDE); + } else { + status = __fh_verify(NULL, net, cred, nfs_vers, client, NULL, fhp, + S_IFREG, may_flags|NFSD_MAY_OWNER_OVERRIDE); + } if (status != nfs_ok) return status; inode = d_inode(fhp->fh_dentry); @@ -1143,7 +1150,8 @@ __be32 nfsd_file_acquire_gc(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct nfsd_file **pnf) { - return nfsd_file_do_acquire(rqstp, fhp, may_flags, NULL, pnf, true); + return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, 0, NULL, + fhp, may_flags, NULL, pnf, true); } /** @@ -1167,7 +1175,47 @@ __be32 nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct nfsd_file **pnf) { - return nfsd_file_do_acquire(rqstp, fhp, may_flags, NULL, pnf, false); + return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, 0, NULL, + fhp, may_flags, NULL, pnf, false); +} + +/** + * nfsd_file_acquire_local - Get a struct nfsd_file with an open file for localio + * @net: The network namespace in which to perform a lookup + * @cred: the user credential with which to validate access + * @nfs_vers: NFS version number to assume for request + * @client: the auth_domain for LOCALIO lookup + * @fhp: the NFS filehandle of the file to be opened + * @may_flags: NFSD_MAY_ settings for the file + * @pnf: OUT: new or found "struct nfsd_file" object + * + * This file lookup interface provide access to a file given the + * filehandle and credential. No connection-based authorisation + * is performed and in that way it is quite different to other + * file access mediated by nfsd. It allows a kernel module such as the NFS + * client to reach across network and filesystem namespaces to access + * a file. The security implications of this should be carefully + * considered before use. + * + * The nfsd_file object returned by this API is reference-counted + * and garbage-collected. The object is retained for a few + * seconds after the final nfsd_file_put() in case the caller + * wants to re-use it. + * + * Return values: + * %nfs_ok - @pnf points to an nfsd_file with its reference + * count boosted. + * + * On error, an nfsstat value in network byte order is returned. + */ +__be32 +nfsd_file_acquire_local(struct net *net, struct svc_cred *cred, + int nfs_vers, struct auth_domain *client, + struct svc_fh *fhp, + unsigned int may_flags, struct nfsd_file **pnf) +{ + return nfsd_file_do_acquire(NULL, net, cred, nfs_vers, client, + fhp, may_flags, NULL, pnf, true); } /** @@ -1193,7 +1241,8 @@ nfsd_file_acquire_opened(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct file *file, struct nfsd_file **pnf) { - return nfsd_file_do_acquire(rqstp, fhp, may_flags, file, pnf, false); + return nfsd_file_do_acquire(rqstp, SVC_NET(rqstp), NULL, 0, NULL, + fhp, may_flags, file, pnf, false); } /* diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h index 3fbec24eea6c..6dab41f8541e 100644 --- a/fs/nfsd/filecache.h +++ b/fs/nfsd/filecache.h @@ -66,5 +66,9 @@ __be32 nfsd_file_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp, __be32 nfsd_file_acquire_opened(struct svc_rqst *rqstp, struct svc_fh *fhp, unsigned int may_flags, struct file *file, struct nfsd_file **nfp); +__be32 nfsd_file_acquire_local(struct net *net, struct svc_cred *cred, + int nfs_vers, struct auth_domain *client, + struct svc_fh *fhp, + unsigned int may_flags, struct nfsd_file **pnf); int nfsd_file_cache_stats_show(struct seq_file *m, void *v); #endif /* _FS_NFSD_FILECACHE_H */ diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index 19e173187ab9..3635c0390cab 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -300,7 +300,7 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct net *net, return error; } -static __be32 +__be32 __fh_verify(struct svc_rqst *rqstp, struct net *net, struct svc_cred *cred, int nfs_vers, struct auth_domain *client, diff --git a/fs/nfsd/nfsfh.h b/fs/nfsd/nfsfh.h index 8d46e203d139..1429bee0ac1c 100644 --- a/fs/nfsd/nfsfh.h +++ b/fs/nfsd/nfsfh.h @@ -217,6 +217,11 @@ extern char * SVCFH_fmt(struct svc_fh *fhp); * Function prototypes */ __be32 fh_verify(struct svc_rqst *, struct svc_fh *, umode_t, int); +__be32 __fh_verify(struct svc_rqst *rqstp, + struct net *net, struct svc_cred *cred, + int nfs_vers, struct auth_domain *client, + struct auth_domain *gssclient, + struct svc_fh *fhp, umode_t type, int access); __be32 fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *); __be32 fh_update(struct svc_fh *); void fh_put(struct svc_fh *);