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author | Chuck Lever <chuck.lever@oracle.com> | 2018-03-27 10:54:21 -0400 |
---|---|---|
committer | J. Bruce Fields <bfields@redhat.com> | 2018-04-03 15:08:16 -0400 |
commit | 38a70315599dedacd9ff3bd1016f9048c9d0ad12 (patch) | |
tree | 047a3d88ea7e400827c806be98c8a22c35428db8 /fs/nfsd | |
parent | 8154ef2776aa512a3eaa0e7db030dc4803354d61 (diff) | |
download | op-kernel-dev-38a70315599dedacd9ff3bd1016f9048c9d0ad12.zip op-kernel-dev-38a70315599dedacd9ff3bd1016f9048c9d0ad12.tar.gz |
NFSD: Clean up legacy NFS SYMLINK argument XDR decoders
Move common code in NFSD's legacy SYMLINK decoders into a helper.
The immediate benefits include:
- one fewer data copies on transports that support DDP
- consistent error checking across all versions
- reduction of code duplication
- support for both legal forms of SYMLINK requests on RDMA
transports for all versions of NFS (in particular, NFSv2, for
completeness)
In the long term, this helper is an appropriate spot to perform a
per-transport call-out to fill the pathname argument using, say,
RDMA Reads.
Filling the pathname in the proc function also means that eventually
the incoming filehandle can be interpreted so that filesystem-
specific memory can be allocated as a sink for the pathname
argument, rather than using anonymous pages.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'fs/nfsd')
-rw-r--r-- | fs/nfsd/nfs3proc.c | 10 | ||||
-rw-r--r-- | fs/nfsd/nfs3xdr.c | 51 | ||||
-rw-r--r-- | fs/nfsd/nfsproc.c | 14 | ||||
-rw-r--r-- | fs/nfsd/nfsxdr.c | 49 | ||||
-rw-r--r-- | fs/nfsd/xdr.h | 1 | ||||
-rw-r--r-- | fs/nfsd/xdr3.h | 1 | ||||
-rw-r--r-- | fs/nfsd/xdr4.h | 2 |
7 files changed, 63 insertions, 65 deletions
diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 2dd95eb..6259a4b 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -283,6 +283,16 @@ nfsd3_proc_symlink(struct svc_rqst *rqstp) struct nfsd3_diropres *resp = rqstp->rq_resp; __be32 nfserr; + if (argp->tlen == 0) + RETURN_STATUS(nfserr_inval); + if (argp->tlen > NFS3_MAXPATHLEN) + RETURN_STATUS(nfserr_nametoolong); + + argp->tname = svc_fill_symlink_pathname(rqstp, &argp->first, + argp->tlen); + if (IS_ERR(argp->tname)) + RETURN_STATUS(nfserrno(PTR_ERR(argp->tname))); + dprintk("nfsd: SYMLINK(3) %s %.*s -> %.*s\n", SVCFH_fmt(&argp->ffh), argp->flen, argp->fname, diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index e19fc5d..3192b54 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -481,51 +481,24 @@ int nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p) { struct nfsd3_symlinkargs *args = rqstp->rq_argp; - unsigned int len, avail; - char *old, *new; - struct kvec *vec; + char *base = (char *)p; + size_t dlen; if (!(p = decode_fh(p, &args->ffh)) || - !(p = decode_filename(p, &args->fname, &args->flen)) - ) + !(p = decode_filename(p, &args->fname, &args->flen))) return 0; p = decode_sattr3(p, &args->attrs); - /* now decode the pathname, which might be larger than the first page. - * As we have to check for nul's anyway, we copy it into a new page - * This page appears in the rq_res.pages list, but as pages_len is always - * 0, it won't get in the way - */ - len = ntohl(*p++); - if (len == 0 || len > NFS3_MAXPATHLEN || len >= PAGE_SIZE) - return 0; - args->tname = new = page_address(*(rqstp->rq_next_page++)); - args->tlen = len; - /* first copy and check from the first page */ - old = (char*)p; - vec = &rqstp->rq_arg.head[0]; - if ((void *)old > vec->iov_base + vec->iov_len) - return 0; - avail = vec->iov_len - (old - (char*)vec->iov_base); - while (len && avail && *old) { - *new++ = *old++; - len--; - avail--; - } - /* now copy next page if there is one */ - if (len && !avail && rqstp->rq_arg.page_len) { - avail = min_t(unsigned int, rqstp->rq_arg.page_len, PAGE_SIZE); - old = page_address(rqstp->rq_arg.pages[0]); - } - while (len && avail && *old) { - *new++ = *old++; - len--; - avail--; - } - *new = '\0'; - if (len) - return 0; + args->tlen = ntohl(*p++); + args->first.iov_base = p; + args->first.iov_len = rqstp->rq_arg.head[0].iov_len; + args->first.iov_len -= (char *)p - base; + + dlen = args->first.iov_len + rqstp->rq_arg.page_len + + rqstp->rq_arg.tail[0].iov_len; + if (dlen < XDR_QUADLEN(args->tlen) << 2) + return 0; return 1; } diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c index 1995ea6..f107f9f 100644 --- a/fs/nfsd/nfsproc.c +++ b/fs/nfsd/nfsproc.c @@ -449,17 +449,19 @@ nfsd_proc_symlink(struct svc_rqst *rqstp) struct svc_fh newfh; __be32 nfserr; + if (argp->tlen > NFS_MAXPATHLEN) + return nfserr_nametoolong; + + argp->tname = svc_fill_symlink_pathname(rqstp, &argp->first, + argp->tlen); + if (IS_ERR(argp->tname)) + return nfserrno(PTR_ERR(argp->tname)); + dprintk("nfsd: SYMLINK %s %.*s -> %.*s\n", SVCFH_fmt(&argp->ffh), argp->flen, argp->fname, argp->tlen, argp->tname); fh_init(&newfh, NFS_FHSIZE); - /* - * Crazy hack: the request fits in a page, and already-decoded - * attributes follow argp->tname, so it's safe to just write a - * null to ensure it's null-terminated: - */ - argp->tname[argp->tlen] = '\0'; nfserr = nfsd_symlink(rqstp, &argp->ffh, argp->fname, argp->flen, argp->tname, &newfh); diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index db24ae8..a43e826 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -71,22 +71,6 @@ decode_filename(__be32 *p, char **namp, unsigned int *lenp) } static __be32 * -decode_pathname(__be32 *p, char **namp, unsigned int *lenp) -{ - char *name; - unsigned int i; - - if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXPATHLEN)) != NULL) { - for (i = 0, name = *namp; i < *lenp; i++, name++) { - if (*name == '\0') - return NULL; - } - } - - return p; -} - -static __be32 * decode_sattr(__be32 *p, struct iattr *iap) { u32 tmp, tmp1; @@ -384,14 +368,39 @@ int nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p) { struct nfsd_symlinkargs *args = rqstp->rq_argp; + char *base = (char *)p; + size_t xdrlen; if ( !(p = decode_fh(p, &args->ffh)) - || !(p = decode_filename(p, &args->fname, &args->flen)) - || !(p = decode_pathname(p, &args->tname, &args->tlen))) + || !(p = decode_filename(p, &args->fname, &args->flen))) return 0; - p = decode_sattr(p, &args->attrs); - return xdr_argsize_check(rqstp, p); + args->tlen = ntohl(*p++); + if (args->tlen == 0) + return 0; + + args->first.iov_base = p; + args->first.iov_len = rqstp->rq_arg.head[0].iov_len; + args->first.iov_len -= (char *)p - base; + + /* This request is never larger than a page. Therefore, + * transport will deliver either: + * 1. pathname in the pagelist -> sattr is in the tail. + * 2. everything in the head buffer -> sattr is in the head. + */ + if (rqstp->rq_arg.page_len) { + if (args->tlen != rqstp->rq_arg.page_len) + return 0; + p = rqstp->rq_arg.tail[0].iov_base; + } else { + xdrlen = XDR_QUADLEN(args->tlen); + if (xdrlen > args->first.iov_len - (8 * sizeof(__be32))) + return 0; + p += xdrlen; + } + decode_sattr(p, &args->attrs); + + return 1; } int diff --git a/fs/nfsd/xdr.h b/fs/nfsd/xdr.h index a765c41..ea7cca3 100644 --- a/fs/nfsd/xdr.h +++ b/fs/nfsd/xdr.h @@ -72,6 +72,7 @@ struct nfsd_symlinkargs { char * tname; unsigned int tlen; struct iattr attrs; + struct kvec first; }; struct nfsd_readdirargs { diff --git a/fs/nfsd/xdr3.h b/fs/nfsd/xdr3.h index deccf7f..2cb29e9 100644 --- a/fs/nfsd/xdr3.h +++ b/fs/nfsd/xdr3.h @@ -90,6 +90,7 @@ struct nfsd3_symlinkargs { char * tname; unsigned int tlen; struct iattr attrs; + struct kvec first; }; struct nfsd3_readdirargs { diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h index 7cbc129..468020f 100644 --- a/fs/nfsd/xdr4.h +++ b/fs/nfsd/xdr4.h @@ -110,6 +110,7 @@ struct nfsd4_create { struct { u32 datalen; char *data; + struct kvec first; } link; /* NF4LNK */ struct { u32 specdata1; @@ -124,6 +125,7 @@ struct nfsd4_create { }; #define cr_datalen u.link.datalen #define cr_data u.link.data +#define cr_first u.link.first #define cr_specdata1 u.dev.specdata1 #define cr_specdata2 u.dev.specdata2 |