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author | Chuck Lever <chuck.lever@oracle.com> | 2023-11-17 17:14:33 -0500 |
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committer | Chuck Lever <chuck.lever@oracle.com> | 2024-01-07 17:54:25 -0500 |
commit | c21fd7a8e86c0e069b512462ffd69bcf179387c8 (patch) | |
tree | da4b072de2d33d6dd110ce336f4c023b5b7e0bce /fs/nfsd/vfs.c | |
parent | deb704281f076097b0347116a82edeba96697db1 (diff) | |
download | linux-stable-c21fd7a8e86c0e069b512462ffd69bcf179387c8.tar.gz linux-stable-c21fd7a8e86c0e069b512462ffd69bcf179387c8.tar.bz2 linux-stable-c21fd7a8e86c0e069b512462ffd69bcf179387c8.zip |
NFSD: Replace RQ_SPLICE_OK in nfsd_read()
RQ_SPLICE_OK is a bit of a layering violation. Also, a subsequent
patch is going to provide a mechanism for always disabling splice
reads.
Splicing is an issue only for NFS READs, so refactor nfsd_read() to
check the auth type directly instead of relying on an rq_flag
setting.
The new helper will be added into the NFSv4 read path in a
subsequent patch.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Diffstat (limited to 'fs/nfsd/vfs.c')
-rw-r--r-- | fs/nfsd/vfs.c | 26 |
1 files changed, 25 insertions, 1 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index c260cbfa8176..cc63fd52a493 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1210,6 +1210,30 @@ out_nfserr: } /** + * nfsd_read_splice_ok - check if spliced reading is supported + * @rqstp: RPC transaction context + * + * Return values: + * %true: nfsd_splice_read() may be used + * %false: nfsd_splice_read() must not be used + * + * NFS READ normally uses splice to send data in-place. However the + * data in cache can change after the reply's MIC is computed but + * before the RPC reply is sent. To prevent the client from + * rejecting the server-computed MIC in this somewhat rare case, do + * not use splice with the GSS integrity and privacy services. + */ +bool nfsd_read_splice_ok(struct svc_rqst *rqstp) +{ + switch (svc_auth_flavor(rqstp)) { + case RPC_AUTH_GSS_KRB5I: + case RPC_AUTH_GSS_KRB5P: + return false; + } + return true; +} + +/** * nfsd_read - Read data from a file * @rqstp: RPC transaction context * @fhp: file handle of file to be read @@ -1238,7 +1262,7 @@ __be32 nfsd_read(struct svc_rqst *rqstp, struct svc_fh *fhp, return err; file = nf->nf_file; - if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &rqstp->rq_flags)) + if (file->f_op->splice_read && nfsd_read_splice_ok(rqstp)) err = nfsd_splice_read(rqstp, fhp, file, offset, count, eof); else err = nfsd_iter_read(rqstp, fhp, file, offset, count, 0, eof); |