/
connect.c
4119 lines (3616 loc) · 105 KB
/
connect.c
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/*
* fs/cifs/connect.c
*
* Copyright (C) International Business Machines Corp., 2002,2011
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/net.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/pagemap.h>
#include <linux/ctype.h>
#include <linux/utsname.h>
#include <linux/mempool.h>
#include <linux/delay.h>
#include <linux/completion.h>
#include <linux/kthread.h>
#include <linux/pagevec.h>
#include <linux/freezer.h>
#include <linux/namei.h>
#include <asm/uaccess.h>
#include <asm/processor.h>
#include <linux/inet.h>
#include <linux/module.h>
#include <keys/user-type.h>
#include <net/ipv6.h>
#include <linux/parser.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "ntlmssp.h"
#include "nterr.h"
#include "rfc1002pdu.h"
#include "fscache.h"
#define CIFS_PORT 445
#define RFC1001_PORT 139
extern mempool_t *cifs_req_poolp;
/* FIXME: should these be tunable? */
#define TLINK_ERROR_EXPIRE (1 * HZ)
#define TLINK_IDLE_EXPIRE (600 * HZ)
enum {
/* Mount options that take no arguments */
Opt_user_xattr, Opt_nouser_xattr,
Opt_forceuid, Opt_noforceuid,
Opt_forcegid, Opt_noforcegid,
Opt_noblocksend, Opt_noautotune,
Opt_hard, Opt_soft, Opt_perm, Opt_noperm,
Opt_mapchars, Opt_nomapchars, Opt_sfu,
Opt_nosfu, Opt_nodfs, Opt_posixpaths,
Opt_noposixpaths, Opt_nounix,
Opt_nocase,
Opt_brl, Opt_nobrl,
Opt_forcemandatorylock, Opt_setuids,
Opt_nosetuids, Opt_dynperm, Opt_nodynperm,
Opt_nohard, Opt_nosoft,
Opt_nointr, Opt_intr,
Opt_nostrictsync, Opt_strictsync,
Opt_serverino, Opt_noserverino,
Opt_rwpidforward, Opt_cifsacl, Opt_nocifsacl,
Opt_acl, Opt_noacl, Opt_locallease,
Opt_sign, Opt_seal, Opt_noac,
Opt_fsc, Opt_mfsymlinks,
Opt_multiuser, Opt_sloppy, Opt_nosharesock,
/* Mount options which take numeric value */
Opt_backupuid, Opt_backupgid, Opt_uid,
Opt_cruid, Opt_gid, Opt_file_mode,
Opt_dirmode, Opt_port,
Opt_rsize, Opt_wsize, Opt_actimeo,
/* Mount options which take string value */
Opt_user, Opt_pass, Opt_ip,
Opt_domain, Opt_srcaddr, Opt_iocharset,
Opt_netbiosname, Opt_servern,
Opt_ver, Opt_vers, Opt_sec, Opt_cache,
/* Mount options to be ignored */
Opt_ignore,
/* Options which could be blank */
Opt_blank_pass,
Opt_blank_user,
Opt_blank_ip,
Opt_err
};
static const match_table_t cifs_mount_option_tokens = {
{ Opt_user_xattr, "user_xattr" },
{ Opt_nouser_xattr, "nouser_xattr" },
{ Opt_forceuid, "forceuid" },
{ Opt_noforceuid, "noforceuid" },
{ Opt_forcegid, "forcegid" },
{ Opt_noforcegid, "noforcegid" },
{ Opt_noblocksend, "noblocksend" },
{ Opt_noautotune, "noautotune" },
{ Opt_hard, "hard" },
{ Opt_soft, "soft" },
{ Opt_perm, "perm" },
{ Opt_noperm, "noperm" },
{ Opt_mapchars, "mapchars" },
{ Opt_nomapchars, "nomapchars" },
{ Opt_sfu, "sfu" },
{ Opt_nosfu, "nosfu" },
{ Opt_nodfs, "nodfs" },
{ Opt_posixpaths, "posixpaths" },
{ Opt_noposixpaths, "noposixpaths" },
{ Opt_nounix, "nounix" },
{ Opt_nounix, "nolinux" },
{ Opt_nocase, "nocase" },
{ Opt_nocase, "ignorecase" },
{ Opt_brl, "brl" },
{ Opt_nobrl, "nobrl" },
{ Opt_nobrl, "nolock" },
{ Opt_forcemandatorylock, "forcemandatorylock" },
{ Opt_forcemandatorylock, "forcemand" },
{ Opt_setuids, "setuids" },
{ Opt_nosetuids, "nosetuids" },
{ Opt_dynperm, "dynperm" },
{ Opt_nodynperm, "nodynperm" },
{ Opt_nohard, "nohard" },
{ Opt_nosoft, "nosoft" },
{ Opt_nointr, "nointr" },
{ Opt_intr, "intr" },
{ Opt_nostrictsync, "nostrictsync" },
{ Opt_strictsync, "strictsync" },
{ Opt_serverino, "serverino" },
{ Opt_noserverino, "noserverino" },
{ Opt_rwpidforward, "rwpidforward" },
{ Opt_cifsacl, "cifsacl" },
{ Opt_nocifsacl, "nocifsacl" },
{ Opt_acl, "acl" },
{ Opt_noacl, "noacl" },
{ Opt_locallease, "locallease" },
{ Opt_sign, "sign" },
{ Opt_seal, "seal" },
{ Opt_noac, "noac" },
{ Opt_fsc, "fsc" },
{ Opt_mfsymlinks, "mfsymlinks" },
{ Opt_multiuser, "multiuser" },
{ Opt_sloppy, "sloppy" },
{ Opt_nosharesock, "nosharesock" },
{ Opt_backupuid, "backupuid=%s" },
{ Opt_backupgid, "backupgid=%s" },
{ Opt_uid, "uid=%s" },
{ Opt_cruid, "cruid=%s" },
{ Opt_gid, "gid=%s" },
{ Opt_file_mode, "file_mode=%s" },
{ Opt_dirmode, "dirmode=%s" },
{ Opt_dirmode, "dir_mode=%s" },
{ Opt_port, "port=%s" },
{ Opt_rsize, "rsize=%s" },
{ Opt_wsize, "wsize=%s" },
{ Opt_actimeo, "actimeo=%s" },
{ Opt_blank_user, "user=" },
{ Opt_blank_user, "username=" },
{ Opt_user, "user=%s" },
{ Opt_user, "username=%s" },
{ Opt_blank_pass, "pass=" },
{ Opt_blank_pass, "password=" },
{ Opt_pass, "pass=%s" },
{ Opt_pass, "password=%s" },
{ Opt_blank_ip, "ip=" },
{ Opt_blank_ip, "addr=" },
{ Opt_ip, "ip=%s" },
{ Opt_ip, "addr=%s" },
{ Opt_ignore, "unc=%s" },
{ Opt_ignore, "target=%s" },
{ Opt_ignore, "path=%s" },
{ Opt_domain, "dom=%s" },
{ Opt_domain, "domain=%s" },
{ Opt_domain, "workgroup=%s" },
{ Opt_srcaddr, "srcaddr=%s" },
{ Opt_ignore, "prefixpath=%s" },
{ Opt_iocharset, "iocharset=%s" },
{ Opt_netbiosname, "netbiosname=%s" },
{ Opt_servern, "servern=%s" },
{ Opt_ver, "ver=%s" },
{ Opt_vers, "vers=%s" },
{ Opt_sec, "sec=%s" },
{ Opt_cache, "cache=%s" },
{ Opt_ignore, "cred" },
{ Opt_ignore, "credentials" },
{ Opt_ignore, "cred=%s" },
{ Opt_ignore, "credentials=%s" },
{ Opt_ignore, "guest" },
{ Opt_ignore, "rw" },
{ Opt_ignore, "ro" },
{ Opt_ignore, "suid" },
{ Opt_ignore, "nosuid" },
{ Opt_ignore, "exec" },
{ Opt_ignore, "noexec" },
{ Opt_ignore, "nodev" },
{ Opt_ignore, "noauto" },
{ Opt_ignore, "dev" },
{ Opt_ignore, "mand" },
{ Opt_ignore, "nomand" },
{ Opt_ignore, "_netdev" },
{ Opt_err, NULL }
};
enum {
Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
Opt_sec_ntlmsspi, Opt_sec_ntlmssp,
Opt_ntlm, Opt_sec_ntlmi, Opt_sec_ntlmv2,
Opt_sec_ntlmv2i, Opt_sec_lanman,
Opt_sec_none,
Opt_sec_err
};
static const match_table_t cifs_secflavor_tokens = {
{ Opt_sec_krb5, "krb5" },
{ Opt_sec_krb5i, "krb5i" },
{ Opt_sec_krb5p, "krb5p" },
{ Opt_sec_ntlmsspi, "ntlmsspi" },
{ Opt_sec_ntlmssp, "ntlmssp" },
{ Opt_ntlm, "ntlm" },
{ Opt_sec_ntlmi, "ntlmi" },
{ Opt_sec_ntlmv2, "nontlm" },
{ Opt_sec_ntlmv2, "ntlmv2" },
{ Opt_sec_ntlmv2i, "ntlmv2i" },
{ Opt_sec_lanman, "lanman" },
{ Opt_sec_none, "none" },
{ Opt_sec_err, NULL }
};
/* cache flavors */
enum {
Opt_cache_loose,
Opt_cache_strict,
Opt_cache_none,
Opt_cache_err
};
static const match_table_t cifs_cacheflavor_tokens = {
{ Opt_cache_loose, "loose" },
{ Opt_cache_strict, "strict" },
{ Opt_cache_none, "none" },
{ Opt_cache_err, NULL }
};
static const match_table_t cifs_smb_version_tokens = {
{ Smb_1, SMB1_VERSION_STRING },
{ Smb_20, SMB20_VERSION_STRING},
{ Smb_21, SMB21_VERSION_STRING },
{ Smb_30, SMB30_VERSION_STRING },
{ Smb_302, SMB302_VERSION_STRING },
};
static int ip_connect(struct TCP_Server_Info *server);
static int generic_ip_connect(struct TCP_Server_Info *server);
static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
static void cifs_prune_tlinks(struct work_struct *work);
static int cifs_setup_volume_info(struct smb_vol *volume_info, char *mount_data,
const char *devname);
/*
* cifs tcp session reconnection
*
* mark tcp session as reconnecting so temporarily locked
* mark all smb sessions as reconnecting for tcp session
* reconnect tcp session
* wake up waiters on reconnection? - (not needed currently)
*/
int
cifs_reconnect(struct TCP_Server_Info *server)
{
int rc = 0;
struct list_head *tmp, *tmp2;
struct cifs_ses *ses;
struct cifs_tcon *tcon;
struct mid_q_entry *mid_entry;
struct list_head retry_list;
spin_lock(&GlobalMid_Lock);
if (server->tcpStatus == CifsExiting) {
/* the demux thread will exit normally
next time through the loop */
spin_unlock(&GlobalMid_Lock);
return rc;
} else
server->tcpStatus = CifsNeedReconnect;
spin_unlock(&GlobalMid_Lock);
server->maxBuf = 0;
#ifdef CONFIG_CIFS_SMB2
server->max_read = 0;
#endif
cifs_dbg(FYI, "Reconnecting tcp session\n");
/* before reconnecting the tcp session, mark the smb session (uid)
and the tid bad so they are not used until reconnected */
cifs_dbg(FYI, "%s: marking sessions and tcons for reconnect\n",
__func__);
spin_lock(&cifs_tcp_ses_lock);
list_for_each(tmp, &server->smb_ses_list) {
ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
ses->need_reconnect = true;
ses->ipc_tid = 0;
list_for_each(tmp2, &ses->tcon_list) {
tcon = list_entry(tmp2, struct cifs_tcon, tcon_list);
tcon->need_reconnect = true;
}
}
spin_unlock(&cifs_tcp_ses_lock);
/* do not want to be sending data on a socket we are freeing */
cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
mutex_lock(&server->srv_mutex);
if (server->ssocket) {
cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n",
server->ssocket->state, server->ssocket->flags);
kernel_sock_shutdown(server->ssocket, SHUT_WR);
cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n",
server->ssocket->state, server->ssocket->flags);
sock_release(server->ssocket);
server->ssocket = NULL;
}
server->sequence_number = 0;
server->session_estab = false;
kfree(server->session_key.response);
server->session_key.response = NULL;
server->session_key.len = 0;
server->lstrp = jiffies;
mutex_unlock(&server->srv_mutex);
/* mark submitted MIDs for retry and issue callback */
INIT_LIST_HEAD(&retry_list);
cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
spin_lock(&GlobalMid_Lock);
list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
if (mid_entry->mid_state == MID_REQUEST_SUBMITTED)
mid_entry->mid_state = MID_RETRY_NEEDED;
list_move(&mid_entry->qhead, &retry_list);
}
spin_unlock(&GlobalMid_Lock);
cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
list_for_each_safe(tmp, tmp2, &retry_list) {
mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
list_del_init(&mid_entry->qhead);
mid_entry->callback(mid_entry);
}
do {
try_to_freeze();
/* we should try only the port we connected to before */
rc = generic_ip_connect(server);
if (rc) {
cifs_dbg(FYI, "reconnect error %d\n", rc);
msleep(3000);
} else {
atomic_inc(&tcpSesReconnectCount);
spin_lock(&GlobalMid_Lock);
if (server->tcpStatus != CifsExiting)
server->tcpStatus = CifsNeedNegotiate;
spin_unlock(&GlobalMid_Lock);
}
} while (server->tcpStatus == CifsNeedReconnect);
return rc;
}
static void
cifs_echo_request(struct work_struct *work)
{
int rc;
struct TCP_Server_Info *server = container_of(work,
struct TCP_Server_Info, echo.work);
/*
* We cannot send an echo if it is disabled or until the
* NEGOTIATE_PROTOCOL request is done, which is indicated by
* server->ops->need_neg() == true. Also, no need to ping if
* we got a response recently.
*/
if (!server->ops->need_neg || server->ops->need_neg(server) ||
(server->ops->can_echo && !server->ops->can_echo(server)) ||
time_before(jiffies, server->lstrp + SMB_ECHO_INTERVAL - HZ))
goto requeue_echo;
rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
if (rc)
cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
server->hostname);
requeue_echo:
queue_delayed_work(cifsiod_wq, &server->echo, SMB_ECHO_INTERVAL);
}
static bool
allocate_buffers(struct TCP_Server_Info *server)
{
if (!server->bigbuf) {
server->bigbuf = (char *)cifs_buf_get();
if (!server->bigbuf) {
cifs_dbg(VFS, "No memory for large SMB response\n");
msleep(3000);
/* retry will check if exiting */
return false;
}
} else if (server->large_buf) {
/* we are reusing a dirty large buf, clear its start */
memset(server->bigbuf, 0, HEADER_SIZE(server));
}
if (!server->smallbuf) {
server->smallbuf = (char *)cifs_small_buf_get();
if (!server->smallbuf) {
cifs_dbg(VFS, "No memory for SMB response\n");
msleep(1000);
/* retry will check if exiting */
return false;
}
/* beginning of smb buffer is cleared in our buf_get */
} else {
/* if existing small buf clear beginning */
memset(server->smallbuf, 0, HEADER_SIZE(server));
}
return true;
}
static bool
server_unresponsive(struct TCP_Server_Info *server)
{
/*
* We need to wait 2 echo intervals to make sure we handle such
* situations right:
* 1s client sends a normal SMB request
* 2s client gets a response
* 30s echo workqueue job pops, and decides we got a response recently
* and don't need to send another
* ...
* 65s kernel_recvmsg times out, and we see that we haven't gotten
* a response in >60s.
*/
if (server->tcpStatus == CifsGood &&
time_after(jiffies, server->lstrp + 2 * SMB_ECHO_INTERVAL)) {
cifs_dbg(VFS, "Server %s has not responded in %d seconds. Reconnecting...\n",
server->hostname, (2 * SMB_ECHO_INTERVAL) / HZ);
cifs_reconnect(server);
wake_up(&server->response_q);
return true;
}
return false;
}
/*
* kvec_array_init - clone a kvec array, and advance into it
* @new: pointer to memory for cloned array
* @iov: pointer to original array
* @nr_segs: number of members in original array
* @bytes: number of bytes to advance into the cloned array
*
* This function will copy the array provided in iov to a section of memory
* and advance the specified number of bytes into the new array. It returns
* the number of segments in the new array. "new" must be at least as big as
* the original iov array.
*/
static unsigned int
kvec_array_init(struct kvec *new, struct kvec *iov, unsigned int nr_segs,
size_t bytes)
{
size_t base = 0;
while (bytes || !iov->iov_len) {
int copy = min(bytes, iov->iov_len);
bytes -= copy;
base += copy;
if (iov->iov_len == base) {
iov++;
nr_segs--;
base = 0;
}
}
memcpy(new, iov, sizeof(*iov) * nr_segs);
new->iov_base += base;
new->iov_len -= base;
return nr_segs;
}
static struct kvec *
get_server_iovec(struct TCP_Server_Info *server, unsigned int nr_segs)
{
struct kvec *new_iov;
if (server->iov && nr_segs <= server->nr_iov)
return server->iov;
/* not big enough -- allocate a new one and release the old */
new_iov = kmalloc(sizeof(*new_iov) * nr_segs, GFP_NOFS);
if (new_iov) {
kfree(server->iov);
server->iov = new_iov;
server->nr_iov = nr_segs;
}
return new_iov;
}
int
cifs_readv_from_socket(struct TCP_Server_Info *server, struct kvec *iov_orig,
unsigned int nr_segs, unsigned int to_read)
{
int length = 0;
int total_read;
unsigned int segs;
struct msghdr smb_msg;
struct kvec *iov;
iov = get_server_iovec(server, nr_segs);
if (!iov)
return -ENOMEM;
smb_msg.msg_control = NULL;
smb_msg.msg_controllen = 0;
for (total_read = 0; to_read; total_read += length, to_read -= length) {
try_to_freeze();
if (server_unresponsive(server)) {
total_read = -EAGAIN;
break;
}
segs = kvec_array_init(iov, iov_orig, nr_segs, total_read);
length = kernel_recvmsg(server->ssocket, &smb_msg,
iov, segs, to_read, 0);
if (server->tcpStatus == CifsExiting) {
total_read = -ESHUTDOWN;
break;
} else if (server->tcpStatus == CifsNeedReconnect) {
cifs_reconnect(server);
total_read = -EAGAIN;
break;
} else if (length == -ERESTARTSYS ||
length == -EAGAIN ||
length == -EINTR) {
/*
* Minimum sleep to prevent looping, allowing socket
* to clear and app threads to set tcpStatus
* CifsNeedReconnect if server hung.
*/
usleep_range(1000, 2000);
length = 0;
continue;
} else if (length <= 0) {
cifs_dbg(FYI, "Received no data or error: expecting %d\n"
"got %d", to_read, length);
cifs_reconnect(server);
total_read = -EAGAIN;
break;
}
}
return total_read;
}
int
cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
unsigned int to_read)
{
struct kvec iov;
iov.iov_base = buf;
iov.iov_len = to_read;
return cifs_readv_from_socket(server, &iov, 1, to_read);
}
static bool
is_smb_response(struct TCP_Server_Info *server, unsigned char type)
{
/*
* The first byte big endian of the length field,
* is actually not part of the length but the type
* with the most common, zero, as regular data.
*/
switch (type) {
case RFC1002_SESSION_MESSAGE:
/* Regular SMB response */
return true;
case RFC1002_SESSION_KEEP_ALIVE:
cifs_dbg(FYI, "RFC 1002 session keep alive\n");
break;
case RFC1002_POSITIVE_SESSION_RESPONSE:
cifs_dbg(FYI, "RFC 1002 positive session response\n");
break;
case RFC1002_NEGATIVE_SESSION_RESPONSE:
/*
* We get this from Windows 98 instead of an error on
* SMB negprot response.
*/
cifs_dbg(FYI, "RFC 1002 negative session response\n");
/* give server a second to clean up */
msleep(1000);
/*
* Always try 445 first on reconnect since we get NACK
* on some if we ever connected to port 139 (the NACK
* is since we do not begin with RFC1001 session
* initialize frame).
*/
cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
cifs_reconnect(server);
wake_up(&server->response_q);
break;
default:
cifs_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
cifs_reconnect(server);
}
return false;
}
void
dequeue_mid(struct mid_q_entry *mid, bool malformed)
{
#ifdef CONFIG_CIFS_STATS2
mid->when_received = jiffies;
#endif
spin_lock(&GlobalMid_Lock);
if (!malformed)
mid->mid_state = MID_RESPONSE_RECEIVED;
else
mid->mid_state = MID_RESPONSE_MALFORMED;
list_del_init(&mid->qhead);
spin_unlock(&GlobalMid_Lock);
}
static void
handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
char *buf, int malformed)
{
if (server->ops->check_trans2 &&
server->ops->check_trans2(mid, server, buf, malformed))
return;
mid->resp_buf = buf;
mid->large_buf = server->large_buf;
/* Was previous buf put in mpx struct for multi-rsp? */
if (!mid->multiRsp) {
/* smb buffer will be freed by user thread */
if (server->large_buf)
server->bigbuf = NULL;
else
server->smallbuf = NULL;
}
dequeue_mid(mid, malformed);
}
static void clean_demultiplex_info(struct TCP_Server_Info *server)
{
int length;
/* take it off the list, if it's not already */
spin_lock(&cifs_tcp_ses_lock);
list_del_init(&server->tcp_ses_list);
spin_unlock(&cifs_tcp_ses_lock);
spin_lock(&GlobalMid_Lock);
server->tcpStatus = CifsExiting;
spin_unlock(&GlobalMid_Lock);
wake_up_all(&server->response_q);
/* check if we have blocked requests that need to free */
spin_lock(&server->req_lock);
if (server->credits <= 0)
server->credits = 1;
spin_unlock(&server->req_lock);
/*
* Although there should not be any requests blocked on this queue it
* can not hurt to be paranoid and try to wake up requests that may
* haven been blocked when more than 50 at time were on the wire to the
* same server - they now will see the session is in exit state and get
* out of SendReceive.
*/
wake_up_all(&server->request_q);
/* give those requests time to exit */
msleep(125);
if (server->ssocket) {
sock_release(server->ssocket);
server->ssocket = NULL;
}
if (!list_empty(&server->pending_mid_q)) {
struct list_head dispose_list;
struct mid_q_entry *mid_entry;
struct list_head *tmp, *tmp2;
INIT_LIST_HEAD(&dispose_list);
spin_lock(&GlobalMid_Lock);
list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
cifs_dbg(FYI, "Clearing mid 0x%llx\n", mid_entry->mid);
mid_entry->mid_state = MID_SHUTDOWN;
list_move(&mid_entry->qhead, &dispose_list);
}
spin_unlock(&GlobalMid_Lock);
/* now walk dispose list and issue callbacks */
list_for_each_safe(tmp, tmp2, &dispose_list) {
mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
cifs_dbg(FYI, "Callback mid 0x%llx\n", mid_entry->mid);
list_del_init(&mid_entry->qhead);
mid_entry->callback(mid_entry);
}
/* 1/8th of sec is more than enough time for them to exit */
msleep(125);
}
if (!list_empty(&server->pending_mid_q)) {
/*
* mpx threads have not exited yet give them at least the smb
* send timeout time for long ops.
*
* Due to delays on oplock break requests, we need to wait at
* least 45 seconds before giving up on a request getting a
* response and going ahead and killing cifsd.
*/
cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
msleep(46000);
/*
* If threads still have not exited they are probably never
* coming home not much else we can do but free the memory.
*/
}
kfree(server->hostname);
kfree(server->iov);
kfree(server);
length = atomic_dec_return(&tcpSesAllocCount);
if (length > 0)
mempool_resize(cifs_req_poolp, length + cifs_min_rcv,
GFP_KERNEL);
}
static int
standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
{
int length;
char *buf = server->smallbuf;
unsigned int pdu_length = get_rfc1002_length(buf);
/* make sure this will fit in a large buffer */
if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) - 4) {
cifs_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
cifs_reconnect(server);
wake_up(&server->response_q);
return -EAGAIN;
}
/* switch to large buffer if too big for a small one */
if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
server->large_buf = true;
memcpy(server->bigbuf, buf, server->total_read);
buf = server->bigbuf;
}
/* now read the rest */
length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
pdu_length - HEADER_SIZE(server) + 1 + 4);
if (length < 0)
return length;
server->total_read += length;
dump_smb(buf, server->total_read);
/*
* We know that we received enough to get to the MID as we
* checked the pdu_length earlier. Now check to see
* if the rest of the header is OK. We borrow the length
* var for the rest of the loop to avoid a new stack var.
*
* 48 bytes is enough to display the header and a little bit
* into the payload for debugging purposes.
*/
length = server->ops->check_message(buf, server->total_read);
if (length != 0)
cifs_dump_mem("Bad SMB: ", buf,
min_t(unsigned int, server->total_read, 48));
if (server->ops->is_status_pending &&
server->ops->is_status_pending(buf, server, length))
return -1;
if (!mid)
return length;
handle_mid(mid, server, buf, length);
return 0;
}
static int
cifs_demultiplex_thread(void *p)
{
int length;
struct TCP_Server_Info *server = p;
unsigned int pdu_length;
char *buf = NULL;
struct task_struct *task_to_wake = NULL;
struct mid_q_entry *mid_entry;
current->flags |= PF_MEMALLOC;
cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
length = atomic_inc_return(&tcpSesAllocCount);
if (length > 1)
mempool_resize(cifs_req_poolp, length + cifs_min_rcv,
GFP_KERNEL);
set_freezable();
while (server->tcpStatus != CifsExiting) {
if (try_to_freeze())
continue;
if (!allocate_buffers(server))
continue;
server->large_buf = false;
buf = server->smallbuf;
pdu_length = 4; /* enough to get RFC1001 header */
length = cifs_read_from_socket(server, buf, pdu_length);
if (length < 0)
continue;
server->total_read = length;
/*
* The right amount was read from socket - 4 bytes,
* so we can now interpret the length field.
*/
pdu_length = get_rfc1002_length(buf);
cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
if (!is_smb_response(server, buf[0]))
continue;
/* make sure we have enough to get to the MID */
if (pdu_length < HEADER_SIZE(server) - 1 - 4) {
cifs_dbg(VFS, "SMB response too short (%u bytes)\n",
pdu_length);
cifs_reconnect(server);
wake_up(&server->response_q);
continue;
}
/* read down to the MID */
length = cifs_read_from_socket(server, buf + 4,
HEADER_SIZE(server) - 1 - 4);
if (length < 0)
continue;
server->total_read += length;
mid_entry = server->ops->find_mid(server, buf);
if (!mid_entry || !mid_entry->receive)
length = standard_receive3(server, mid_entry);
else
length = mid_entry->receive(server, mid_entry);
if (length < 0)
continue;
if (server->large_buf)
buf = server->bigbuf;
server->lstrp = jiffies;
if (mid_entry != NULL) {
if (!mid_entry->multiRsp || mid_entry->multiEnd)
mid_entry->callback(mid_entry);
} else if (!server->ops->is_oplock_break ||
!server->ops->is_oplock_break(buf, server)) {
cifs_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
atomic_read(&midCount));
cifs_dump_mem("Received Data is: ", buf,
HEADER_SIZE(server));
#ifdef CONFIG_CIFS_DEBUG2
if (server->ops->dump_detail)
server->ops->dump_detail(buf);
cifs_dump_mids(server);
#endif /* CIFS_DEBUG2 */
}
} /* end while !EXITING */
/* buffer usually freed in free_mid - need to free it here on exit */
cifs_buf_release(server->bigbuf);
if (server->smallbuf) /* no sense logging a debug message if NULL */
cifs_small_buf_release(server->smallbuf);
task_to_wake = xchg(&server->tsk, NULL);
clean_demultiplex_info(server);
/* if server->tsk was NULL then wait for a signal before exiting */
if (!task_to_wake) {
set_current_state(TASK_INTERRUPTIBLE);
while (!signal_pending(current)) {
schedule();
set_current_state(TASK_INTERRUPTIBLE);
}
set_current_state(TASK_RUNNING);
}
module_put_and_exit(0);
}
/* extract the host portion of the UNC string */
static char *
extract_hostname(const char *unc)
{
const char *src;
char *dst, *delim;
unsigned int len;
/* skip double chars at beginning of string */
/* BB: check validity of these bytes? */
src = unc + 2;
/* delimiter between hostname and sharename is always '\\' now */
delim = strchr(src, '\\');
if (!delim)
return ERR_PTR(-EINVAL);
len = delim - src;
dst = kmalloc((len + 1), GFP_KERNEL);
if (dst == NULL)
return ERR_PTR(-ENOMEM);
memcpy(dst, src, len);
dst[len] = '\0';
return dst;
}
static int get_option_ul(substring_t args[], unsigned long *option)
{
int rc;
char *string;
string = match_strdup(args);
if (string == NULL)
return -ENOMEM;
rc = kstrtoul(string, 0, option);
kfree(string);
return rc;
}
static int get_option_uid(substring_t args[], kuid_t *result)
{
unsigned long value;
kuid_t uid;
int rc;
rc = get_option_ul(args, &value);
if (rc)
return rc;
uid = make_kuid(current_user_ns(), value);
if (!uid_valid(uid))
return -EINVAL;