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ef5305f1f7
strcpy to dirent->d_name could overflow the buffer, use strscpy to check the provided string length and error out if the size was too big. While we are here, make the function return an error when the pdu parsing failed, instead of returning the pdu offset as if it had been a success... Link: http://lkml.kernel.org/r/1536339057-21974-4-git-send-email-asmadeus@codewreck.org Addresses-Coverity-ID: 139133 ("Copy into fixed size buffer") Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
642 lines
14 KiB
C
642 lines
14 KiB
C
/*
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* net/9p/protocol.c
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*
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* 9P Protocol Support Code
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*
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* Copyright (C) 2008 by Eric Van Hensbergen <ericvh@gmail.com>
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*
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* Base on code from Anthony Liguori <aliguori@us.ibm.com>
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* Copyright (C) 2008 by IBM, Corp.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to:
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* Free Software Foundation
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* 51 Franklin Street, Fifth Floor
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* Boston, MA 02111-1301 USA
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*
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*/
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/uaccess.h>
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#include <linux/slab.h>
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#include <linux/sched.h>
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#include <linux/stddef.h>
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#include <linux/types.h>
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#include <linux/uio.h>
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#include <net/9p/9p.h>
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#include <net/9p/client.h>
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#include "protocol.h"
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#include <trace/events/9p.h>
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static int
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p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...);
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void p9stat_free(struct p9_wstat *stbuf)
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{
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kfree(stbuf->name);
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stbuf->name = NULL;
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kfree(stbuf->uid);
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stbuf->uid = NULL;
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kfree(stbuf->gid);
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stbuf->gid = NULL;
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kfree(stbuf->muid);
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stbuf->muid = NULL;
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kfree(stbuf->extension);
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stbuf->extension = NULL;
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}
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EXPORT_SYMBOL(p9stat_free);
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size_t pdu_read(struct p9_fcall *pdu, void *data, size_t size)
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{
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size_t len = min(pdu->size - pdu->offset, size);
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memcpy(data, &pdu->sdata[pdu->offset], len);
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pdu->offset += len;
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return size - len;
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}
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static size_t pdu_write(struct p9_fcall *pdu, const void *data, size_t size)
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{
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size_t len = min(pdu->capacity - pdu->size, size);
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memcpy(&pdu->sdata[pdu->size], data, len);
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pdu->size += len;
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return size - len;
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}
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static size_t
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pdu_write_u(struct p9_fcall *pdu, struct iov_iter *from, size_t size)
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{
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size_t len = min(pdu->capacity - pdu->size, size);
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struct iov_iter i = *from;
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if (!copy_from_iter_full(&pdu->sdata[pdu->size], len, &i))
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len = 0;
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pdu->size += len;
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return size - len;
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}
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/*
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b - int8_t
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w - int16_t
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d - int32_t
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q - int64_t
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s - string
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u - numeric uid
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g - numeric gid
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S - stat
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Q - qid
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D - data blob (int32_t size followed by void *, results are not freed)
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T - array of strings (int16_t count, followed by strings)
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R - array of qids (int16_t count, followed by qids)
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A - stat for 9p2000.L (p9_stat_dotl)
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? - if optional = 1, continue parsing
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*/
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static int
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p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
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va_list ap)
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{
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const char *ptr;
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int errcode = 0;
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for (ptr = fmt; *ptr; ptr++) {
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switch (*ptr) {
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case 'b':{
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int8_t *val = va_arg(ap, int8_t *);
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if (pdu_read(pdu, val, sizeof(*val))) {
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errcode = -EFAULT;
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break;
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}
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}
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break;
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case 'w':{
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int16_t *val = va_arg(ap, int16_t *);
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__le16 le_val;
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if (pdu_read(pdu, &le_val, sizeof(le_val))) {
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errcode = -EFAULT;
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break;
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}
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*val = le16_to_cpu(le_val);
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}
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break;
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case 'd':{
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int32_t *val = va_arg(ap, int32_t *);
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__le32 le_val;
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if (pdu_read(pdu, &le_val, sizeof(le_val))) {
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errcode = -EFAULT;
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break;
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}
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*val = le32_to_cpu(le_val);
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}
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break;
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case 'q':{
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int64_t *val = va_arg(ap, int64_t *);
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__le64 le_val;
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if (pdu_read(pdu, &le_val, sizeof(le_val))) {
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errcode = -EFAULT;
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break;
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}
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*val = le64_to_cpu(le_val);
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}
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break;
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case 's':{
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char **sptr = va_arg(ap, char **);
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uint16_t len;
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errcode = p9pdu_readf(pdu, proto_version,
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"w", &len);
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if (errcode)
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break;
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*sptr = kmalloc(len + 1, GFP_NOFS);
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if (*sptr == NULL) {
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errcode = -ENOMEM;
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break;
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}
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if (pdu_read(pdu, *sptr, len)) {
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errcode = -EFAULT;
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kfree(*sptr);
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*sptr = NULL;
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} else
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(*sptr)[len] = 0;
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}
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break;
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case 'u': {
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kuid_t *uid = va_arg(ap, kuid_t *);
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__le32 le_val;
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if (pdu_read(pdu, &le_val, sizeof(le_val))) {
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errcode = -EFAULT;
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break;
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}
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*uid = make_kuid(&init_user_ns,
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le32_to_cpu(le_val));
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} break;
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case 'g': {
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kgid_t *gid = va_arg(ap, kgid_t *);
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__le32 le_val;
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if (pdu_read(pdu, &le_val, sizeof(le_val))) {
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errcode = -EFAULT;
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break;
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}
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*gid = make_kgid(&init_user_ns,
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le32_to_cpu(le_val));
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} break;
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case 'Q':{
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struct p9_qid *qid =
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va_arg(ap, struct p9_qid *);
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errcode = p9pdu_readf(pdu, proto_version, "bdq",
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&qid->type, &qid->version,
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&qid->path);
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}
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break;
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case 'S':{
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struct p9_wstat *stbuf =
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va_arg(ap, struct p9_wstat *);
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memset(stbuf, 0, sizeof(struct p9_wstat));
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stbuf->n_uid = stbuf->n_muid = INVALID_UID;
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stbuf->n_gid = INVALID_GID;
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errcode =
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p9pdu_readf(pdu, proto_version,
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"wwdQdddqssss?sugu",
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&stbuf->size, &stbuf->type,
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&stbuf->dev, &stbuf->qid,
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&stbuf->mode, &stbuf->atime,
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&stbuf->mtime, &stbuf->length,
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&stbuf->name, &stbuf->uid,
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&stbuf->gid, &stbuf->muid,
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&stbuf->extension,
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&stbuf->n_uid, &stbuf->n_gid,
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&stbuf->n_muid);
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if (errcode)
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p9stat_free(stbuf);
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}
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break;
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case 'D':{
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uint32_t *count = va_arg(ap, uint32_t *);
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void **data = va_arg(ap, void **);
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errcode =
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p9pdu_readf(pdu, proto_version, "d", count);
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if (!errcode) {
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*count =
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min_t(uint32_t, *count,
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pdu->size - pdu->offset);
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*data = &pdu->sdata[pdu->offset];
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}
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}
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break;
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case 'T':{
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uint16_t *nwname = va_arg(ap, uint16_t *);
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char ***wnames = va_arg(ap, char ***);
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errcode = p9pdu_readf(pdu, proto_version,
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"w", nwname);
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if (!errcode) {
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*wnames =
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kmalloc_array(*nwname,
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sizeof(char *),
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GFP_NOFS);
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if (!*wnames)
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errcode = -ENOMEM;
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}
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if (!errcode) {
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int i;
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for (i = 0; i < *nwname; i++) {
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errcode =
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p9pdu_readf(pdu,
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proto_version,
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"s",
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&(*wnames)[i]);
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if (errcode)
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break;
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}
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}
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if (errcode) {
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if (*wnames) {
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int i;
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for (i = 0; i < *nwname; i++)
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kfree((*wnames)[i]);
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}
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kfree(*wnames);
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*wnames = NULL;
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}
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}
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break;
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case 'R':{
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uint16_t *nwqid = va_arg(ap, uint16_t *);
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struct p9_qid **wqids =
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va_arg(ap, struct p9_qid **);
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*wqids = NULL;
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errcode =
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p9pdu_readf(pdu, proto_version, "w", nwqid);
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if (!errcode) {
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*wqids =
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kmalloc_array(*nwqid,
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sizeof(struct p9_qid),
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GFP_NOFS);
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if (*wqids == NULL)
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errcode = -ENOMEM;
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}
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if (!errcode) {
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int i;
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for (i = 0; i < *nwqid; i++) {
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errcode =
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p9pdu_readf(pdu,
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proto_version,
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"Q",
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&(*wqids)[i]);
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if (errcode)
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break;
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}
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}
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if (errcode) {
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kfree(*wqids);
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*wqids = NULL;
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}
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}
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break;
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case 'A': {
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struct p9_stat_dotl *stbuf =
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va_arg(ap, struct p9_stat_dotl *);
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memset(stbuf, 0, sizeof(struct p9_stat_dotl));
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errcode =
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p9pdu_readf(pdu, proto_version,
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"qQdugqqqqqqqqqqqqqqq",
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&stbuf->st_result_mask,
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&stbuf->qid,
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&stbuf->st_mode,
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&stbuf->st_uid, &stbuf->st_gid,
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&stbuf->st_nlink,
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&stbuf->st_rdev, &stbuf->st_size,
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&stbuf->st_blksize, &stbuf->st_blocks,
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&stbuf->st_atime_sec,
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&stbuf->st_atime_nsec,
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&stbuf->st_mtime_sec,
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&stbuf->st_mtime_nsec,
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&stbuf->st_ctime_sec,
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&stbuf->st_ctime_nsec,
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&stbuf->st_btime_sec,
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&stbuf->st_btime_nsec,
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&stbuf->st_gen,
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&stbuf->st_data_version);
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}
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break;
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case '?':
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if ((proto_version != p9_proto_2000u) &&
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(proto_version != p9_proto_2000L))
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return 0;
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break;
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default:
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BUG();
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break;
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}
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if (errcode)
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break;
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}
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return errcode;
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}
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int
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p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
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va_list ap)
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{
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const char *ptr;
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int errcode = 0;
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for (ptr = fmt; *ptr; ptr++) {
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switch (*ptr) {
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case 'b':{
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int8_t val = va_arg(ap, int);
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if (pdu_write(pdu, &val, sizeof(val)))
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errcode = -EFAULT;
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}
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break;
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case 'w':{
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__le16 val = cpu_to_le16(va_arg(ap, int));
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if (pdu_write(pdu, &val, sizeof(val)))
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errcode = -EFAULT;
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}
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break;
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case 'd':{
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__le32 val = cpu_to_le32(va_arg(ap, int32_t));
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if (pdu_write(pdu, &val, sizeof(val)))
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errcode = -EFAULT;
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}
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break;
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case 'q':{
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__le64 val = cpu_to_le64(va_arg(ap, int64_t));
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if (pdu_write(pdu, &val, sizeof(val)))
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errcode = -EFAULT;
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}
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break;
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case 's':{
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const char *sptr = va_arg(ap, const char *);
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uint16_t len = 0;
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if (sptr)
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len = min_t(size_t, strlen(sptr),
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USHRT_MAX);
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errcode = p9pdu_writef(pdu, proto_version,
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"w", len);
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if (!errcode && pdu_write(pdu, sptr, len))
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errcode = -EFAULT;
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}
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break;
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case 'u': {
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kuid_t uid = va_arg(ap, kuid_t);
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__le32 val = cpu_to_le32(
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from_kuid(&init_user_ns, uid));
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if (pdu_write(pdu, &val, sizeof(val)))
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errcode = -EFAULT;
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} break;
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case 'g': {
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kgid_t gid = va_arg(ap, kgid_t);
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__le32 val = cpu_to_le32(
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from_kgid(&init_user_ns, gid));
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if (pdu_write(pdu, &val, sizeof(val)))
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errcode = -EFAULT;
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} break;
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case 'Q':{
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const struct p9_qid *qid =
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va_arg(ap, const struct p9_qid *);
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errcode =
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p9pdu_writef(pdu, proto_version, "bdq",
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qid->type, qid->version,
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qid->path);
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} break;
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case 'S':{
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const struct p9_wstat *stbuf =
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va_arg(ap, const struct p9_wstat *);
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errcode =
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p9pdu_writef(pdu, proto_version,
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"wwdQdddqssss?sugu",
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stbuf->size, stbuf->type,
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stbuf->dev, &stbuf->qid,
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stbuf->mode, stbuf->atime,
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stbuf->mtime, stbuf->length,
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stbuf->name, stbuf->uid,
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stbuf->gid, stbuf->muid,
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stbuf->extension, stbuf->n_uid,
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stbuf->n_gid, stbuf->n_muid);
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} break;
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case 'V':{
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uint32_t count = va_arg(ap, uint32_t);
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struct iov_iter *from =
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va_arg(ap, struct iov_iter *);
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errcode = p9pdu_writef(pdu, proto_version, "d",
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count);
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if (!errcode && pdu_write_u(pdu, from, count))
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errcode = -EFAULT;
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}
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break;
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case 'T':{
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uint16_t nwname = va_arg(ap, int);
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const char **wnames = va_arg(ap, const char **);
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errcode = p9pdu_writef(pdu, proto_version, "w",
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nwname);
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if (!errcode) {
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int i;
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for (i = 0; i < nwname; i++) {
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errcode =
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p9pdu_writef(pdu,
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proto_version,
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"s",
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wnames[i]);
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if (errcode)
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break;
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}
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}
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}
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break;
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case 'R':{
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uint16_t nwqid = va_arg(ap, int);
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struct p9_qid *wqids =
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va_arg(ap, struct p9_qid *);
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errcode = p9pdu_writef(pdu, proto_version, "w",
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nwqid);
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if (!errcode) {
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int i;
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for (i = 0; i < nwqid; i++) {
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errcode =
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p9pdu_writef(pdu,
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proto_version,
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"Q",
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&wqids[i]);
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if (errcode)
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break;
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}
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}
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}
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break;
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case 'I':{
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struct p9_iattr_dotl *p9attr = va_arg(ap,
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struct p9_iattr_dotl *);
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errcode = p9pdu_writef(pdu, proto_version,
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"ddugqqqqq",
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p9attr->valid,
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p9attr->mode,
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p9attr->uid,
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p9attr->gid,
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p9attr->size,
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p9attr->atime_sec,
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p9attr->atime_nsec,
|
|
p9attr->mtime_sec,
|
|
p9attr->mtime_nsec);
|
|
}
|
|
break;
|
|
case '?':
|
|
if ((proto_version != p9_proto_2000u) &&
|
|
(proto_version != p9_proto_2000L))
|
|
return 0;
|
|
break;
|
|
default:
|
|
BUG();
|
|
break;
|
|
}
|
|
|
|
if (errcode)
|
|
break;
|
|
}
|
|
|
|
return errcode;
|
|
}
|
|
|
|
int p9pdu_readf(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
int ret;
|
|
|
|
va_start(ap, fmt);
|
|
ret = p9pdu_vreadf(pdu, proto_version, fmt, ap);
|
|
va_end(ap);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
p9pdu_writef(struct p9_fcall *pdu, int proto_version, const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
int ret;
|
|
|
|
va_start(ap, fmt);
|
|
ret = p9pdu_vwritef(pdu, proto_version, fmt, ap);
|
|
va_end(ap);
|
|
|
|
return ret;
|
|
}
|
|
|
|
int p9stat_read(struct p9_client *clnt, char *buf, int len, struct p9_wstat *st)
|
|
{
|
|
struct p9_fcall fake_pdu;
|
|
int ret;
|
|
|
|
fake_pdu.size = len;
|
|
fake_pdu.capacity = len;
|
|
fake_pdu.sdata = buf;
|
|
fake_pdu.offset = 0;
|
|
|
|
ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "S", st);
|
|
if (ret) {
|
|
p9_debug(P9_DEBUG_9P, "<<< p9stat_read failed: %d\n", ret);
|
|
trace_9p_protocol_dump(clnt, &fake_pdu);
|
|
return ret;
|
|
}
|
|
|
|
return fake_pdu.offset;
|
|
}
|
|
EXPORT_SYMBOL(p9stat_read);
|
|
|
|
int p9pdu_prepare(struct p9_fcall *pdu, int16_t tag, int8_t type)
|
|
{
|
|
pdu->id = type;
|
|
return p9pdu_writef(pdu, 0, "dbw", 0, type, tag);
|
|
}
|
|
|
|
int p9pdu_finalize(struct p9_client *clnt, struct p9_fcall *pdu)
|
|
{
|
|
int size = pdu->size;
|
|
int err;
|
|
|
|
pdu->size = 0;
|
|
err = p9pdu_writef(pdu, 0, "d", size);
|
|
pdu->size = size;
|
|
|
|
trace_9p_protocol_dump(clnt, pdu);
|
|
p9_debug(P9_DEBUG_9P, ">>> size=%d type: %d tag: %d\n",
|
|
pdu->size, pdu->id, pdu->tag);
|
|
|
|
return err;
|
|
}
|
|
|
|
void p9pdu_reset(struct p9_fcall *pdu)
|
|
{
|
|
pdu->offset = 0;
|
|
pdu->size = 0;
|
|
}
|
|
|
|
int p9dirent_read(struct p9_client *clnt, char *buf, int len,
|
|
struct p9_dirent *dirent)
|
|
{
|
|
struct p9_fcall fake_pdu;
|
|
int ret;
|
|
char *nameptr;
|
|
|
|
fake_pdu.size = len;
|
|
fake_pdu.capacity = len;
|
|
fake_pdu.sdata = buf;
|
|
fake_pdu.offset = 0;
|
|
|
|
ret = p9pdu_readf(&fake_pdu, clnt->proto_version, "Qqbs", &dirent->qid,
|
|
&dirent->d_off, &dirent->d_type, &nameptr);
|
|
if (ret) {
|
|
p9_debug(P9_DEBUG_9P, "<<< p9dirent_read failed: %d\n", ret);
|
|
trace_9p_protocol_dump(clnt, &fake_pdu);
|
|
return ret;
|
|
}
|
|
|
|
ret = strscpy(dirent->d_name, nameptr, sizeof(dirent->d_name));
|
|
if (ret < 0) {
|
|
p9_debug(P9_DEBUG_ERROR,
|
|
"On the wire dirent name too long: %s\n",
|
|
nameptr);
|
|
kfree(nameptr);
|
|
return ret;
|
|
}
|
|
kfree(nameptr);
|
|
|
|
return fake_pdu.offset;
|
|
}
|
|
EXPORT_SYMBOL(p9dirent_read);
|