linux/fs/nfsd/nfs3xdr.c

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
// SPDX-License-Identifier: GPL-2.0
/*
* XDR support for nfsd/protocol version 3.
*
* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
*
* 2003-08-09 Jamie Lokier: Use htonl() for nanoseconds, not htons()!
*/
#include <linux/namei.h>
#include <linux/sunrpc/svc_xprt.h>
#include "xdr3.h"
#include "auth.h"
#include "netns.h"
#include "vfs.h"
#define NFSDDBG_FACILITY NFSDDBG_XDR
/*
* Mapping of S_IF* types to NFS file types
*/
static u32 nfs3_ftypes[] = {
NF3NON, NF3FIFO, NF3CHR, NF3BAD,
NF3DIR, NF3BAD, NF3BLK, NF3BAD,
NF3REG, NF3BAD, NF3LNK, NF3BAD,
NF3SOCK, NF3BAD, NF3LNK, NF3BAD,
};
/*
* XDR functions for basic NFS types
*/
static __be32 *
encode_time3(__be32 *p, struct timespec64 *time)
{
*p++ = htonl((u32) time->tv_sec); *p++ = htonl(time->tv_nsec);
return p;
}
static __be32 *
decode_time3(__be32 *p, struct timespec64 *time)
{
time->tv_sec = ntohl(*p++);
time->tv_nsec = ntohl(*p++);
return p;
}
static __be32 *
decode_fh(__be32 *p, struct svc_fh *fhp)
{
unsigned int size;
fh_init(fhp, NFS3_FHSIZE);
size = ntohl(*p++);
if (size > NFS3_FHSIZE)
return NULL;
memcpy(&fhp->fh_handle.fh_base, p, size);
fhp->fh_handle.fh_size = size;
return p + XDR_QUADLEN(size);
}
/* Helper function for NFSv3 ACL code */
__be32 *nfs3svc_decode_fh(__be32 *p, struct svc_fh *fhp)
{
return decode_fh(p, fhp);
}
static __be32 *
encode_fh(__be32 *p, struct svc_fh *fhp)
{
unsigned int size = fhp->fh_handle.fh_size;
*p++ = htonl(size);
if (size) p[XDR_QUADLEN(size)-1]=0;
memcpy(p, &fhp->fh_handle.fh_base, size);
return p + XDR_QUADLEN(size);
}
/*
* Decode a file name and make sure that the path contains
* no slashes or null bytes.
*/
static __be32 *
decode_filename(__be32 *p, char **namp, unsigned int *lenp)
{
char *name;
unsigned int i;
if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS3_MAXNAMLEN)) != NULL) {
for (i = 0, name = *namp; i < *lenp; i++, name++) {
if (*name == '\0' || *name == '/')
return NULL;
}
}
return p;
}
static __be32 *
decode_sattr3(__be32 *p, struct iattr *iap, struct user_namespace *userns)
{
u32 tmp;
iap->ia_valid = 0;
if (*p++) {
iap->ia_valid |= ATTR_MODE;
iap->ia_mode = ntohl(*p++);
}
if (*p++) {
iap->ia_uid = make_kuid(userns, ntohl(*p++));
if (uid_valid(iap->ia_uid))
iap->ia_valid |= ATTR_UID;
}
if (*p++) {
iap->ia_gid = make_kgid(userns, ntohl(*p++));
if (gid_valid(iap->ia_gid))
iap->ia_valid |= ATTR_GID;
}
if (*p++) {
u64 newsize;
iap->ia_valid |= ATTR_SIZE;
p = xdr_decode_hyper(p, &newsize);
iap->ia_size = min_t(u64, newsize, NFS_OFFSET_MAX);
}
if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
iap->ia_valid |= ATTR_ATIME;
} else if (tmp == 2) { /* set to client time */
iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
iap->ia_atime.tv_sec = ntohl(*p++);
iap->ia_atime.tv_nsec = ntohl(*p++);
}
if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
iap->ia_valid |= ATTR_MTIME;
} else if (tmp == 2) { /* set to client time */
iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
iap->ia_mtime.tv_sec = ntohl(*p++);
iap->ia_mtime.tv_nsec = ntohl(*p++);
}
return p;
}
static __be32 *encode_fsid(__be32 *p, struct svc_fh *fhp)
{
u64 f;
switch(fsid_source(fhp)) {
default:
case FSIDSOURCE_DEV:
p = xdr_encode_hyper(p, (u64)huge_encode_dev
(fhp->fh_dentry->d_sb->s_dev));
break;
case FSIDSOURCE_FSID:
p = xdr_encode_hyper(p, (u64) fhp->fh_export->ex_fsid);
break;
case FSIDSOURCE_UUID:
f = ((u64*)fhp->fh_export->ex_uuid)[0];
f ^= ((u64*)fhp->fh_export->ex_uuid)[1];
p = xdr_encode_hyper(p, f);
break;
}
return p;
}
static __be32 *
encode_fattr3(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
struct kstat *stat)
{
struct user_namespace *userns = nfsd_user_namespace(rqstp);
*p++ = htonl(nfs3_ftypes[(stat->mode & S_IFMT) >> 12]);
*p++ = htonl((u32) (stat->mode & S_IALLUGO));
*p++ = htonl((u32) stat->nlink);
*p++ = htonl((u32) from_kuid_munged(userns, stat->uid));
*p++ = htonl((u32) from_kgid_munged(userns, stat->gid));
if (S_ISLNK(stat->mode) && stat->size > NFS3_MAXPATHLEN) {
p = xdr_encode_hyper(p, (u64) NFS3_MAXPATHLEN);
} else {
p = xdr_encode_hyper(p, (u64) stat->size);
}
p = xdr_encode_hyper(p, ((u64)stat->blocks) << 9);
*p++ = htonl((u32) MAJOR(stat->rdev));
*p++ = htonl((u32) MINOR(stat->rdev));
p = encode_fsid(p, fhp);
p = xdr_encode_hyper(p, stat->ino);
p = encode_time3(p, &stat->atime);
p = encode_time3(p, &stat->mtime);
p = encode_time3(p, &stat->ctime);
return p;
}
static __be32 *
encode_saved_post_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
/* Attributes to follow */
*p++ = xdr_one;
return encode_fattr3(rqstp, p, fhp, &fhp->fh_post_attr);
}
/*
* Encode post-operation attributes.
* The inode may be NULL if the call failed because of a stale file
* handle. In this case, no attributes are returned.
*/
static __be32 *
encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
struct dentry *dentry = fhp->fh_dentry;
if (dentry && d_really_is_positive(dentry)) {
__be32 err;
struct kstat stat;
err = fh_getattr(fhp, &stat);
if (!err) {
*p++ = xdr_one; /* attributes follow */
lease_get_mtime(d_inode(dentry), &stat.mtime);
return encode_fattr3(rqstp, p, fhp, &stat);
}
}
*p++ = xdr_zero;
return p;
}
/* Helper for NFSv3 ACLs */
__be32 *
nfs3svc_encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
return encode_post_op_attr(rqstp, p, fhp);
}
/*
* Enocde weak cache consistency data
*/
static __be32 *
encode_wcc_data(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
struct dentry *dentry = fhp->fh_dentry;
if (dentry && d_really_is_positive(dentry) && fhp->fh_post_saved) {
if (fhp->fh_pre_saved) {
*p++ = xdr_one;
p = xdr_encode_hyper(p, (u64) fhp->fh_pre_size);
p = encode_time3(p, &fhp->fh_pre_mtime);
p = encode_time3(p, &fhp->fh_pre_ctime);
} else {
*p++ = xdr_zero;
}
return encode_saved_post_attr(rqstp, p, fhp);
}
/* no pre- or post-attrs */
*p++ = xdr_zero;
return encode_post_op_attr(rqstp, p, fhp);
}
/*
* Fill in the pre_op attr for the wcc data
*/
void fill_pre_wcc(struct svc_fh *fhp)
{
struct inode *inode;
struct kstat stat;
__be32 err;
if (fhp->fh_pre_saved)
return;
inode = d_inode(fhp->fh_dentry);
err = fh_getattr(fhp, &stat);
if (err) {
/* Grab the times from inode anyway */
stat.mtime = inode->i_mtime;
stat.ctime = inode->i_ctime;
stat.size = inode->i_size;
}
fhp->fh_pre_mtime = stat.mtime;
fhp->fh_pre_ctime = stat.ctime;
fhp->fh_pre_size = stat.size;
fhp->fh_pre_change = nfsd4_change_attribute(&stat, inode);
fhp->fh_pre_saved = true;
}
/*
* Fill in the post_op attr for the wcc data
*/
void fill_post_wcc(struct svc_fh *fhp)
{
__be32 err;
if (fhp->fh_post_saved)
printk("nfsd: inode locked twice during operation.\n");
err = fh_getattr(fhp, &fhp->fh_post_attr);
fhp->fh_post_change = nfsd4_change_attribute(&fhp->fh_post_attr,
d_inode(fhp->fh_dentry));
if (err) {
fhp->fh_post_saved = false;
/* Grab the ctime anyway - set_change_info might use it */
fhp->fh_post_attr.ctime = d_inode(fhp->fh_dentry)->i_ctime;
} else
fhp->fh_post_saved = true;
}
/*
* XDR decode functions
*/
int
nfs3svc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_fhandle *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_sattrargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
if ((args->check_guard = ntohl(*p++)) != 0) {
struct timespec64 time;
p = decode_time3(p, &time);
args->guardtime = time.tv_sec;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_diropargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh))
|| !(p = decode_filename(p, &args->name, &args->len)))
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_accessargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
args->access = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readargs *args = rqstp->rq_argp;
unsigned int len;
int v;
u32 max_blocksize = svc_max_payload(rqstp);
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->offset);
args->count = ntohl(*p++);
len = min(args->count, max_blocksize);
/* set up the kvec */
v=0;
while (len > 0) {
struct page *p = *(rqstp->rq_next_page++);
rqstp->rq_vec[v].iov_base = page_address(p);
rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
len -= rqstp->rq_vec[v].iov_len;
v++;
}
args->vlen = v;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_writeargs *args = rqstp->rq_argp;
NFSD: Clean up legacy NFS WRITE argument XDR decoders Move common code in NFSD's legacy NFS WRITE decoders into a helper. The immediate benefit is reduction of code duplication and some nice micro-optimizations (see below). In the long term, this helper can perform a per-transport call-out to fill the rq_vec (say, using RDMA Reads). The legacy WRITE decoders and procs are changed to work like NFSv4, which constructs the rq_vec just before it is about to call vfs_writev. Why? Calling a transport call-out from the proc instead of the XDR decoder means that the incoming FH can be resolved to a particular filesystem and file. This would allow pages from the backing file to be presented to the transport to be filled, rather than presenting anonymous pages and copying or flipping them into the file's page cache later. I also prefer using the pages in rq_arg.pages, instead of pulling the data pages directly out of the rqstp::rq_pages array. This is currently the way the NFSv3 write decoder works, but the other two do not seem to take this approach. Fixing this removes the only reference to rq_pages found in NFSD, eliminating an NFSD assumption about how transports use the pages in rq_pages. Lastly, avoid setting up the first element of rq_vec as a zero- length buffer. This happens with an RDMA transport when a normal Read chunk is present because the data payload is in rq_arg's page list (none of it is in the head buffer). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-03-27 14:54:07 +00:00
unsigned int len, hdr, dlen;
u32 max_blocksize = svc_max_payload(rqstp);
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->offset);
args->count = ntohl(*p++);
args->stable = ntohl(*p++);
len = args->len = ntohl(*p++);
if ((void *)p > head->iov_base + head->iov_len)
return 0;
/*
* The count must equal the amount of data passed.
*/
if (args->count != args->len)
return 0;
/*
* Check to make sure that we got the right number of
* bytes.
*/
hdr = (void*)p - head->iov_base;
dlen = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len - hdr;
/*
* Round the length of the data which was specified up to
* the next multiple of XDR units and then compare that
* against the length which was actually received.
* Note that when RPCSEC/GSS (for example) is used, the
* data buffer can be padded so dlen might be larger
* than required. It must never be smaller.
*/
if (dlen < XDR_QUADLEN(len)*4)
return 0;
if (args->count > max_blocksize) {
args->count = max_blocksize;
len = args->len = max_blocksize;
}
NFSD: Clean up legacy NFS WRITE argument XDR decoders Move common code in NFSD's legacy NFS WRITE decoders into a helper. The immediate benefit is reduction of code duplication and some nice micro-optimizations (see below). In the long term, this helper can perform a per-transport call-out to fill the rq_vec (say, using RDMA Reads). The legacy WRITE decoders and procs are changed to work like NFSv4, which constructs the rq_vec just before it is about to call vfs_writev. Why? Calling a transport call-out from the proc instead of the XDR decoder means that the incoming FH can be resolved to a particular filesystem and file. This would allow pages from the backing file to be presented to the transport to be filled, rather than presenting anonymous pages and copying or flipping them into the file's page cache later. I also prefer using the pages in rq_arg.pages, instead of pulling the data pages directly out of the rqstp::rq_pages array. This is currently the way the NFSv3 write decoder works, but the other two do not seem to take this approach. Fixing this removes the only reference to rq_pages found in NFSD, eliminating an NFSD assumption about how transports use the pages in rq_pages. Lastly, avoid setting up the first element of rq_vec as a zero- length buffer. This happens with an RDMA transport when a normal Read chunk is present because the data payload is in rq_arg's page list (none of it is in the head buffer). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2018-03-27 14:54:07 +00:00
args->first.iov_base = (void *)p;
args->first.iov_len = head->iov_len - hdr;
return 1;
}
int
nfs3svc_decode_createargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_createargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh))
|| !(p = decode_filename(p, &args->name, &args->len)))
return 0;
switch (args->createmode = ntohl(*p++)) {
case NFS3_CREATE_UNCHECKED:
case NFS3_CREATE_GUARDED:
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
break;
case NFS3_CREATE_EXCLUSIVE:
args->verf = p;
p += 2;
break;
default:
return 0;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_mkdirargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_createargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh)) ||
!(p = decode_filename(p, &args->name, &args->len)))
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_symlinkargs *args = rqstp->rq_argp;
char *base = (char *)p;
size_t dlen;
if (!(p = decode_fh(p, &args->ffh)) ||
!(p = decode_filename(p, &args->fname, &args->flen)))
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
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;
}
int
nfs3svc_decode_mknodargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_mknodargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh))
|| !(p = decode_filename(p, &args->name, &args->len)))
return 0;
args->ftype = ntohl(*p++);
if (args->ftype == NF3BLK || args->ftype == NF3CHR
|| args->ftype == NF3SOCK || args->ftype == NF3FIFO)
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
if (args->ftype == NF3BLK || args->ftype == NF3CHR) {
args->major = ntohl(*p++);
args->minor = ntohl(*p++);
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_renameargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->ffh))
|| !(p = decode_filename(p, &args->fname, &args->flen))
|| !(p = decode_fh(p, &args->tfh))
|| !(p = decode_filename(p, &args->tname, &args->tlen)))
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readlinkargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
args->buffer = page_address(*(rqstp->rq_next_page++));
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_linkargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->ffh))
|| !(p = decode_fh(p, &args->tfh))
|| !(p = decode_filename(p, &args->tname, &args->tlen)))
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readdirargs *args = rqstp->rq_argp;
int len;
u32 max_blocksize = svc_max_payload(rqstp);
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->cookie);
args->verf = p; p += 2;
args->dircount = ~0;
args->count = ntohl(*p++);
len = args->count = min_t(u32, args->count, max_blocksize);
while (len > 0) {
struct page *p = *(rqstp->rq_next_page++);
if (!args->buffer)
args->buffer = page_address(p);
len -= PAGE_SIZE;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readdirplusargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readdirargs *args = rqstp->rq_argp;
int len;
u32 max_blocksize = svc_max_payload(rqstp);
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->cookie);
args->verf = p; p += 2;
args->dircount = ntohl(*p++);
args->count = ntohl(*p++);
len = args->count = min(args->count, max_blocksize);
while (len > 0) {
struct page *p = *(rqstp->rq_next_page++);
if (!args->buffer)
args->buffer = page_address(p);
len -= PAGE_SIZE;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_commitargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_commitargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->offset);
args->count = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
/*
* XDR encode functions
*/
/*
* There must be an encoding function for void results so svc_process
* will work properly.
*/
int
nfs3svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
{
return xdr_ressize_check(rqstp, p);
}
/* GETATTR */
int
nfs3svc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_attrstat *resp = rqstp->rq_resp;
if (resp->status == 0) {
lease_get_mtime(d_inode(resp->fh.fh_dentry),
&resp->stat.mtime);
p = encode_fattr3(rqstp, p, &resp->fh, &resp->stat);
}
return xdr_ressize_check(rqstp, p);
}
/* SETATTR, REMOVE, RMDIR */
int
nfs3svc_encode_wccstat(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_attrstat *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->fh);
return xdr_ressize_check(rqstp, p);
}
/* LOOKUP */
int
nfs3svc_encode_diropres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_diropres *resp = rqstp->rq_resp;
if (resp->status == 0) {
p = encode_fh(p, &resp->fh);
p = encode_post_op_attr(rqstp, p, &resp->fh);
}
p = encode_post_op_attr(rqstp, p, &resp->dirfh);
return xdr_ressize_check(rqstp, p);
}
/* ACCESS */
int
nfs3svc_encode_accessres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_accessres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0)
*p++ = htonl(resp->access);
return xdr_ressize_check(rqstp, p);
}
/* READLINK */
int
nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readlinkres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->len);
xdr_ressize_check(rqstp, p);
rqstp->rq_res.page_len = resp->len;
if (resp->len & 3) {
/* need to pad the tail */
rqstp->rq_res.tail[0].iov_base = p;
*p = 0;
rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
}
return 1;
} else
return xdr_ressize_check(rqstp, p);
}
/* READ */
int
nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->count);
*p++ = htonl(resp->eof);
*p++ = htonl(resp->count); /* xdr opaque count */
xdr_ressize_check(rqstp, p);
/* now update rqstp->rq_res to reflect data as well */
rqstp->rq_res.page_len = resp->count;
if (resp->count & 3) {
/* need to pad the tail */
rqstp->rq_res.tail[0].iov_base = p;
*p = 0;
rqstp->rq_res.tail[0].iov_len = 4 - (resp->count & 3);
}
return 1;
} else
return xdr_ressize_check(rqstp, p);
}
/* WRITE */
int
nfs3svc_encode_writeres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_writeres *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->count);
*p++ = htonl(resp->committed);
*p++ = resp->verf[0];
*p++ = resp->verf[1];
}
return xdr_ressize_check(rqstp, p);
}
/* CREATE, MKDIR, SYMLINK, MKNOD */
int
nfs3svc_encode_createres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_diropres *resp = rqstp->rq_resp;
if (resp->status == 0) {
*p++ = xdr_one;
p = encode_fh(p, &resp->fh);
p = encode_post_op_attr(rqstp, p, &resp->fh);
}
p = encode_wcc_data(rqstp, p, &resp->dirfh);
return xdr_ressize_check(rqstp, p);
}
/* RENAME */
int
nfs3svc_encode_renameres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_renameres *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->ffh);
p = encode_wcc_data(rqstp, p, &resp->tfh);
return xdr_ressize_check(rqstp, p);
}
/* LINK */
int
nfs3svc_encode_linkres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_linkres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
p = encode_wcc_data(rqstp, p, &resp->tfh);
return xdr_ressize_check(rqstp, p);
}
/* READDIR */
int
nfs3svc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readdirres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0) {
/* stupid readdir cookie */
memcpy(p, resp->verf, 8); p += 2;
xdr_ressize_check(rqstp, p);
if (rqstp->rq_res.head[0].iov_len + (2<<2) > PAGE_SIZE)
return 1; /*No room for trailer */
rqstp->rq_res.page_len = (resp->count) << 2;
/* add the 'tail' to the end of the 'head' page - page 0. */
rqstp->rq_res.tail[0].iov_base = p;
*p++ = 0; /* no more entries */
*p++ = htonl(resp->common.err == nfserr_eof);
rqstp->rq_res.tail[0].iov_len = 2<<2;
return 1;
} else
return xdr_ressize_check(rqstp, p);
}
static __be32 *
encode_entry_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name,
int namlen, u64 ino)
{
*p++ = xdr_one; /* mark entry present */
p = xdr_encode_hyper(p, ino); /* file id */
p = xdr_encode_array(p, name, namlen);/* name length & name */
cd->offset = p; /* remember pointer */
p = xdr_encode_hyper(p, NFS_OFFSET_MAX);/* offset of next entry */
return p;
}
static __be32
compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
const char *name, int namlen, u64 ino)
{
struct svc_export *exp;
struct dentry *dparent, *dchild;
__be32 rv = nfserr_noent;
dparent = cd->fh.fh_dentry;
exp = cd->fh.fh_export;
if (isdotent(name, namlen)) {
if (namlen == 2) {
dchild = dget_parent(dparent);
/* filesystem root - cannot return filehandle for ".." */
if (dchild == dparent)
goto out;
} else
dchild = dget(dparent);
} else
dchild = lookup_positive_unlocked(name, dparent, namlen);
if (IS_ERR(dchild))
return rv;
if (d_mountpoint(dchild))
goto out;
if (dchild->d_inode->i_ino != ino)
goto out;
rv = fh_compose(fhp, exp, dchild, &cd->fh);
out:
dput(dchild);
return rv;
}
static __be32 *encode_entryplus_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name, int namlen, u64 ino)
{
struct svc_fh *fh = &cd->scratch;
__be32 err;
fh_init(fh, NFS3_FHSIZE);
err = compose_entry_fh(cd, fh, name, namlen, ino);
if (err) {
*p++ = 0;
*p++ = 0;
goto out;
}
p = encode_post_op_attr(cd->rqstp, p, fh);
*p++ = xdr_one; /* yes, a file handle follows */
p = encode_fh(p, fh);
out:
fh_put(fh);
return p;
}
/*
* Encode a directory entry. This one works for both normal readdir
* and readdirplus.
* The normal readdir reply requires 2 (fileid) + 1 (stringlen)
* + string + 2 (cookie) + 1 (next) words, i.e. 6 + strlen.
*
* The readdirplus baggage is 1+21 words for post_op_attr, plus the
* file handle.
*/
#define NFS3_ENTRY_BAGGAGE (2 + 1 + 2 + 1)
#define NFS3_ENTRYPLUS_BAGGAGE (1 + 21 + 1 + (NFS3_FHSIZE >> 2))
static int
encode_entry(struct readdir_cd *ccd, const char *name, int namlen,
loff_t offset, u64 ino, unsigned int d_type, int plus)
{
struct nfsd3_readdirres *cd = container_of(ccd, struct nfsd3_readdirres,
common);
__be32 *p = cd->buffer;
caddr_t curr_page_addr = NULL;
struct page ** page;
int slen; /* string (name) length */
int elen; /* estimated entry length in words */
int num_entry_words = 0; /* actual number of words */
if (cd->offset) {
u64 offset64 = offset;
if (unlikely(cd->offset1)) {
/* we ended up with offset on a page boundary */
*cd->offset = htonl(offset64 >> 32);
*cd->offset1 = htonl(offset64 & 0xffffffff);
cd->offset1 = NULL;
} else {
xdr_encode_hyper(cd->offset, offset64);
}
nfsd: fix memory corruption caused by readdir If the result of an NFSv3 readdir{,plus} request results in the "offset" on one entry having to be split across 2 pages, and is sized so that the next directory entry doesn't fit in the requested size, then memory corruption can happen. When encode_entry() is called after encoding the last entry that fits, it notices that ->offset and ->offset1 are set, and so stores the offset value in the two pages as required. It clears ->offset1 but *does not* clear ->offset. Normally this omission doesn't matter as encode_entry_baggage() will be called, and will set ->offset to a suitable value (not on a page boundary). But in the case where cd->buflen < elen and nfserr_toosmall is returned, ->offset is not reset. This means that nfsd3proc_readdirplus will see ->offset with a value 4 bytes before the end of a page, and ->offset1 set to NULL. It will try to write 8bytes to ->offset. If we are lucky, the next page will be read-only, and the system will BUG: unable to handle kernel paging request at... If we are unlucky, some innocent page will have the first 4 bytes corrupted. nfsd3proc_readdir() doesn't even check for ->offset1, it just blindly writes 8 bytes to the offset wherever it is. Fix this by clearing ->offset after it is used, and copying the ->offset handling code from nfsd3_proc_readdirplus into nfsd3_proc_readdir. (Note that the commit hash in the Fixes tag is from the 'history' tree - this bug predates git). Fixes: 0b1d57cf7654 ("[PATCH] kNFSd: Fix nfs3 dentry encoding") Fixes-URL: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=0b1d57cf7654 Cc: stable@vger.kernel.org (v2.6.12+) Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2019-03-04 03:08:22 +00:00
cd->offset = NULL;
}
/*
dprintk("encode_entry(%.*s @%ld%s)\n",
namlen, name, (long) offset, plus? " plus" : "");
*/
/* truncate filename if too long */
namlen = min(namlen, NFS3_MAXNAMLEN);
slen = XDR_QUADLEN(namlen);
elen = slen + NFS3_ENTRY_BAGGAGE
+ (plus? NFS3_ENTRYPLUS_BAGGAGE : 0);
if (cd->buflen < elen) {
cd->common.err = nfserr_toosmall;
return -EINVAL;
}
/* determine which page in rq_respages[] we are currently filling */
for (page = cd->rqstp->rq_respages + 1;
page < cd->rqstp->rq_next_page; page++) {
curr_page_addr = page_address(*page);
if (((caddr_t)cd->buffer >= curr_page_addr) &&
((caddr_t)cd->buffer < curr_page_addr + PAGE_SIZE))
break;
}
if ((caddr_t)(cd->buffer + elen) < (curr_page_addr + PAGE_SIZE)) {
/* encode entry in current page */
p = encode_entry_baggage(cd, p, name, namlen, ino);
if (plus)
p = encode_entryplus_baggage(cd, p, name, namlen, ino);
num_entry_words = p - cd->buffer;
} else if (*(page+1) != NULL) {
/* temporarily encode entry into next page, then move back to
* current and next page in rq_respages[] */
__be32 *p1, *tmp;
int len1, len2;
/* grab next page for temporary storage of entry */
p1 = tmp = page_address(*(page+1));
p1 = encode_entry_baggage(cd, p1, name, namlen, ino);
if (plus)
p1 = encode_entryplus_baggage(cd, p1, name, namlen, ino);
/* determine entry word length and lengths to go in pages */
num_entry_words = p1 - tmp;
len1 = curr_page_addr + PAGE_SIZE - (caddr_t)cd->buffer;
if ((num_entry_words << 2) < len1) {
/* the actual number of words in the entry is less
* than elen and can still fit in the current page
*/
memmove(p, tmp, num_entry_words << 2);
p += num_entry_words;
/* update offset */
cd->offset = cd->buffer + (cd->offset - tmp);
} else {
unsigned int offset_r = (cd->offset - tmp) << 2;
/* update pointer to offset location.
* This is a 64bit quantity, so we need to
* deal with 3 cases:
* - entirely in first page
* - entirely in second page
* - 4 bytes in each page
*/
if (offset_r + 8 <= len1) {
cd->offset = p + (cd->offset - tmp);
} else if (offset_r >= len1) {
cd->offset -= len1 >> 2;
} else {
/* sitting on the fence */
BUG_ON(offset_r != len1 - 4);
cd->offset = p + (cd->offset - tmp);
cd->offset1 = tmp;
}
len2 = (num_entry_words << 2) - len1;
/* move from temp page to current and next pages */
memmove(p, tmp, len1);
memmove(tmp, (caddr_t)tmp+len1, len2);
p = tmp + (len2 >> 2);
}
}
else {
cd->common.err = nfserr_toosmall;
return -EINVAL;
}
cd->buflen -= num_entry_words;
cd->buffer = p;
cd->common.err = nfs_ok;
return 0;
}
int
nfs3svc_encode_entry(void *cd, const char *name,
int namlen, loff_t offset, u64 ino, unsigned int d_type)
{
return encode_entry(cd, name, namlen, offset, ino, d_type, 0);
}
int
nfs3svc_encode_entry_plus(void *cd, const char *name,
int namlen, loff_t offset, u64 ino,
unsigned int d_type)
{
return encode_entry(cd, name, namlen, offset, ino, d_type, 1);
}
/* FSSTAT */
int
nfs3svc_encode_fsstatres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_fsstatres *resp = rqstp->rq_resp;
struct kstatfs *s = &resp->stats;
u64 bs = s->f_bsize;
*p++ = xdr_zero; /* no post_op_attr */
if (resp->status == 0) {
p = xdr_encode_hyper(p, bs * s->f_blocks); /* total bytes */
p = xdr_encode_hyper(p, bs * s->f_bfree); /* free bytes */
p = xdr_encode_hyper(p, bs * s->f_bavail); /* user available bytes */
p = xdr_encode_hyper(p, s->f_files); /* total inodes */
p = xdr_encode_hyper(p, s->f_ffree); /* free inodes */
p = xdr_encode_hyper(p, s->f_ffree); /* user available inodes */
*p++ = htonl(resp->invarsec); /* mean unchanged time */
}
return xdr_ressize_check(rqstp, p);
}
/* FSINFO */
int
nfs3svc_encode_fsinfores(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_fsinfores *resp = rqstp->rq_resp;
*p++ = xdr_zero; /* no post_op_attr */
if (resp->status == 0) {
*p++ = htonl(resp->f_rtmax);
*p++ = htonl(resp->f_rtpref);
*p++ = htonl(resp->f_rtmult);
*p++ = htonl(resp->f_wtmax);
*p++ = htonl(resp->f_wtpref);
*p++ = htonl(resp->f_wtmult);
*p++ = htonl(resp->f_dtpref);
p = xdr_encode_hyper(p, resp->f_maxfilesize);
*p++ = xdr_one;
*p++ = xdr_zero;
*p++ = htonl(resp->f_properties);
}
return xdr_ressize_check(rqstp, p);
}
/* PATHCONF */
int
nfs3svc_encode_pathconfres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_pathconfres *resp = rqstp->rq_resp;
*p++ = xdr_zero; /* no post_op_attr */
if (resp->status == 0) {
*p++ = htonl(resp->p_link_max);
*p++ = htonl(resp->p_name_max);
*p++ = htonl(resp->p_no_trunc);
*p++ = htonl(resp->p_chown_restricted);
*p++ = htonl(resp->p_case_insensitive);
*p++ = htonl(resp->p_case_preserving);
}
return xdr_ressize_check(rqstp, p);
}
/* COMMIT */
int
nfs3svc_encode_commitres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_commitres *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->fh);
/* Write verifier */
if (resp->status == 0) {
*p++ = resp->verf[0];
*p++ = resp->verf[1];
}
return xdr_ressize_check(rqstp, p);
}
/*
* XDR release functions
*/
void
nfs3svc_release_fhandle(struct svc_rqst *rqstp)
{
struct nfsd3_attrstat *resp = rqstp->rq_resp;
fh_put(&resp->fh);
}
void
nfs3svc_release_fhandle2(struct svc_rqst *rqstp)
{
struct nfsd3_fhandle_pair *resp = rqstp->rq_resp;
fh_put(&resp->fh1);
fh_put(&resp->fh2);
}