diff options
Diffstat (limited to 'fs/nfsd/vfs.c')
| -rw-r--r-- | fs/nfsd/vfs.c | 58 |
1 files changed, 51 insertions, 7 deletions
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index e01e4e2ac..4ed1e83de 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1039,7 +1039,10 @@ __be32 nfsd_splice_read(struct svc_rqst *rqstp, struct svc_fh *fhp, ssize_t host_err; trace_nfsd_read_splice(rqstp, fhp, offset, *count); - host_err = splice_direct_to_actor(file, &sd, nfsd_direct_splice_actor); + host_err = rw_verify_area(READ, file, &offset, *count); + if (!host_err) + host_err = splice_direct_to_actor(file, &sd, + nfsd_direct_splice_actor); return nfsd_finish_read(rqstp, fhp, file, offset, count, eof, host_err); } @@ -1176,9 +1179,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, since = READ_ONCE(file->f_wb_err); if (verf) nfsd_copy_write_verifier(verf, nn); - file_start_write(file); host_err = vfs_iter_write(file, &iter, &pos, flags); - file_end_write(file); if (host_err < 0) { commit_reset_write_verifier(nn, rqstp, host_err); goto out_nfserr; @@ -1210,6 +1211,30 @@ 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 +1263,7 @@ __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); @@ -1806,6 +1831,10 @@ retry: } trap = lock_rename(tdentry, fdentry); + if (IS_ERR(trap)) { + err = (rqstp->rq_vers == 2) ? nfserr_acces : nfserr_xdev; + goto out_want_write; + } err = fh_fill_pre_attrs(ffhp); if (err != nfs_ok) goto out_unlock; @@ -1874,6 +1903,7 @@ retry: } out_unlock: unlock_rename(tdentry, fdentry); +out_want_write: fh_drop_write(ffhp); /* @@ -2102,9 +2132,23 @@ static __be32 nfsd_buffered_readdir(struct file *file, struct svc_fh *fhp, return cdp->err; } -/* - * Read entries from a directory. - * The NFSv3/4 verifier we ignore for now. +/** + * nfsd_readdir - Read entries from a directory + * @rqstp: RPC transaction context + * @fhp: NFS file handle of directory to be read + * @offsetp: OUT: seek offset of final entry that was read + * @cdp: OUT: an eof error value + * @func: entry filler actor + * + * This implementation ignores the NFSv3/4 verifier cookie. + * + * NB: normal system calls hold file->f_pos_lock when calling + * ->iterate_shared and ->llseek, but nfsd_readdir() does not. + * Because the struct file acquired here is not visible to other + * threads, it's internal state does not need mutex protection. + * + * Returns nfs_ok on success, otherwise an nfsstat code is + * returned. */ __be32 nfsd_readdir(struct svc_rqst *rqstp, struct svc_fh *fhp, loff_t *offsetp, |