diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 7b755b7f785c..51c3b06e8036 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -147,6 +147,7 @@ nfsd3_proc_read(struct svc_rqst *rqstp, struct nfsd3_readargs *argp, { __be32 nfserr; u32 max_blocksize = svc_max_payload(rqstp); + unsigned long cnt = min(argp->count, max_blocksize); dprintk("nfsd: READ(3) %s %lu bytes at %Lu\n", SVCFH_fmt(&argp->fh), @@ -157,7 +158,7 @@ nfsd3_proc_read(struct svc_rqst *rqstp, struct nfsd3_readargs *argp, * 1 (status) + 22 (post_op_attr) + 1 (count) + 1 (eof) * + 1 (xdr opaque byte count) = 26 */ - resp->count = min(argp->count, max_blocksize); + resp->count = cnt; svc_reserve_auth(rqstp, ((1 + NFS3_POST_OP_ATTR_WORDS + 3)<<2) + resp->count +4); fh_copy(&resp->fh, &argp->fh); @@ -167,8 +168,8 @@ nfsd3_proc_read(struct svc_rqst *rqstp, struct nfsd3_readargs *argp, &resp->count); if (nfserr == 0) { struct inode *inode = d_inode(resp->fh.fh_dentry); - - resp->eof = (argp->offset + resp->count) >= inode->i_size; + resp->eof = nfsd_eof_on_read(cnt, resp->count, argp->offset, + inode->i_size); } RETURN_STATUS(nfserr); diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index aa87954b4af2..9df898ba648f 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3365,6 +3365,7 @@ static __be32 nfsd4_encode_splice_read( struct xdr_stream *xdr = &resp->xdr; struct xdr_buf *buf = xdr->buf; u32 eof; + long len; int space_left; __be32 nfserr; __be32 *p = xdr->p - 2; @@ -3373,6 +3374,7 @@ static __be32 nfsd4_encode_splice_read( if (xdr->end - xdr->p < 1) return nfserr_resource; + len = maxcount; nfserr = nfsd_splice_read(read->rd_rqstp, file, read->rd_offset, &maxcount); if (nfserr) { @@ -3385,8 +3387,8 @@ static __be32 nfsd4_encode_splice_read( return nfserr; } - eof = (read->rd_offset + maxcount >= - d_inode(read->rd_fhp->fh_dentry)->i_size); + eof = nfsd_eof_on_read(len, maxcount, read->rd_offset, + d_inode(read->rd_fhp->fh_dentry)->i_size); *(p++) = htonl(eof); *(p++) = htonl(maxcount); @@ -3456,14 +3458,15 @@ static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp, } read->rd_vlen = v; + len = maxcount; nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec, read->rd_vlen, &maxcount); if (nfserr) return nfserr; xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3)); - eof = (read->rd_offset + maxcount >= - d_inode(read->rd_fhp->fh_dentry)->i_size); + eof = nfsd_eof_on_read(len, maxcount, read->rd_offset, + d_inode(read->rd_fhp->fh_dentry)->i_size); tmp = htonl(eof); write_bytes_to_xdr_buf(xdr->buf, starting_len , &tmp, 4); diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h index c11ba316f23f..2d573ec057f8 100644 --- a/fs/nfsd/vfs.h +++ b/fs/nfsd/vfs.h @@ -139,4 +139,23 @@ static inline int nfsd_create_is_exclusive(int createmode) || createmode == NFS4_CREATE_EXCLUSIVE4_1; } +static inline bool nfsd_eof_on_read(long requested, long read, + loff_t offset, loff_t size) +{ + /* We assume a short read means eof: */ + if (requested > read) + return true; + /* + * A non-short read might also reach end of file. The spec + * still requires us to set eof in that case. + * + * Further operations may have modified the file size since + * the read, so the following check is not atomic with the read. + * We've only seen that cause a problem for a client in the case + * where the read returned a count of 0 without setting eof. + * That case was fixed by the addition of the above check. + */ + return (offset + read >= size); +} + #endif /* LINUX_NFSD_VFS_H */