diff options
Diffstat (limited to 'fs/cifs/connect.c')
-rw-r--r-- | fs/cifs/connect.c | 659 |
1 files changed, 346 insertions, 313 deletions
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index e66297bad412..80c2e3add3a2 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -319,25 +319,328 @@ requeue_echo: queue_delayed_work(system_nrt_wq, &server->echo, SMB_ECHO_INTERVAL); } +static bool +allocate_buffers(char **bigbuf, char **smallbuf, unsigned int size, + bool is_large_buf) +{ + char *bbuf = *bigbuf, *sbuf = *smallbuf; + + if (bbuf == NULL) { + bbuf = (char *)cifs_buf_get(); + if (!bbuf) { + cERROR(1, "No memory for large SMB response"); + msleep(3000); + /* retry will check if exiting */ + return false; + } + } else if (is_large_buf) { + /* we are reusing a dirty large buf, clear its start */ + memset(bbuf, 0, size); + } + + if (sbuf == NULL) { + sbuf = (char *)cifs_small_buf_get(); + if (!sbuf) { + cERROR(1, "No memory for SMB response"); + 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(sbuf, 0, size); + } + + *bigbuf = bbuf; + *smallbuf = sbuf; + + return true; +} + +static int +read_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg, + struct kvec *iov, unsigned int to_read, + unsigned int *ptotal_read, bool is_header_read) +{ + int length, rc = 0; + unsigned int total_read; + char *buf = iov->iov_base; + + for (total_read = 0; total_read < to_read; total_read += length) { + length = kernel_recvmsg(server->ssocket, smb_msg, iov, 1, + to_read - total_read, 0); + if (server->tcpStatus == CifsExiting) { + /* then will exit */ + rc = 2; + break; + } else if (server->tcpStatus == CifsNeedReconnect) { + cifs_reconnect(server); + /* Reconnect wakes up rspns q */ + /* Now we will reread sock */ + rc = 1; + 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; + if (!is_header_read) + continue; + /* Special handling for header read */ + if (total_read) { + iov->iov_base = (to_read - total_read) + + buf; + iov->iov_len = to_read - total_read; + smb_msg->msg_control = NULL; + smb_msg->msg_controllen = 0; + rc = 3; + } else + rc = 1; + break; + } else if (length <= 0) { + cERROR(1, "Received no data, expecting %d", + to_read - total_read); + cifs_reconnect(server); + rc = 1; + break; + } + } + + *ptotal_read = total_read; + return rc; +} + +static bool +check_rfc1002_header(struct TCP_Server_Info *server, char *buf) +{ + char temp = *buf; + unsigned int pdu_length = be32_to_cpu( + ((struct smb_hdr *)buf)->smb_buf_length); + + /* + * 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. + */ + if (temp == (char) RFC1002_SESSION_KEEP_ALIVE) { + return false; + } else if (temp == (char)RFC1002_POSITIVE_SESSION_RESPONSE) { + cFYI(1, "Good RFC 1002 session rsp"); + return false; + } else if (temp == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) { + /* + * We get this from Windows 98 instead of an error on + * SMB negprot response. + */ + cFYI(1, "Negative RFC1002 Session Response Error 0x%x)", + pdu_length); + /* 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); + return false; + } else if (temp != (char) 0) { + cERROR(1, "Unknown RFC 1002 frame"); + cifs_dump_mem(" Received Data: ", buf, 4); + cifs_reconnect(server); + return false; + } + + /* else we have an SMB response */ + if ((pdu_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) || + (pdu_length < sizeof(struct smb_hdr) - 1 - 4)) { + cERROR(1, "Invalid size SMB length %d pdu_length %d", + 4, pdu_length+4); + cifs_reconnect(server); + wake_up(&server->response_q); + return false; + } + + return true; +} + +static struct mid_q_entry * +find_cifs_mid(struct TCP_Server_Info *server, struct smb_hdr *buf, + int *length, bool is_large_buf, bool *is_multi_rsp, char **bigbuf) +{ + struct mid_q_entry *mid = NULL, *tmp_mid, *ret = NULL; + + spin_lock(&GlobalMid_Lock); + list_for_each_entry_safe(mid, tmp_mid, &server->pending_mid_q, qhead) { + if (mid->mid != buf->Mid || + mid->midState != MID_REQUEST_SUBMITTED || + mid->command != buf->Command) + continue; + + if (*length == 0 && check2ndT2(buf, server->maxBuf) > 0) { + /* We have a multipart transact2 resp */ + *is_multi_rsp = true; + if (mid->resp_buf) { + /* merge response - fix up 1st*/ + *length = coalesce_t2(buf, mid->resp_buf); + if (*length > 0) { + *length = 0; + mid->multiRsp = true; + break; + } + /* All parts received or packet is malformed. */ + mid->multiEnd = true; + goto multi_t2_fnd; + } + if (!is_large_buf) { + /*FIXME: switch to already allocated largebuf?*/ + cERROR(1, "1st trans2 resp needs bigbuf"); + } else { + /* Have first buffer */ + mid->resp_buf = buf; + mid->largeBuf = true; + *bigbuf = NULL; + } + break; + } + mid->resp_buf = buf; + mid->largeBuf = is_large_buf; +multi_t2_fnd: + if (*length == 0) + mid->midState = MID_RESPONSE_RECEIVED; + else + mid->midState = MID_RESPONSE_MALFORMED; +#ifdef CONFIG_CIFS_STATS2 + mid->when_received = jiffies; +#endif + list_del_init(&mid->qhead); + ret = mid; + break; + } + spin_unlock(&GlobalMid_Lock); + + return ret; +} + +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. Note that + * cifs_max_pending is normally 50, but can be set at module install + * time to as little as two. + */ + spin_lock(&GlobalMid_Lock); + if (atomic_read(&server->inFlight) >= cifs_max_pending) + atomic_set(&server->inFlight, cifs_max_pending - 1); + /* + * We do not want to set the max_pending too low or we could end up + * with the counter going negative. + */ + spin_unlock(&GlobalMid_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); + cFYI(1, "Clearing mid 0x%x", mid_entry->mid); + mid_entry->midState = 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); + cFYI(1, "Callback mid 0x%x", 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. + */ + cFYI(1, "Wait for exit from demultiplex thread"); + 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); + + length = atomic_dec_return(&tcpSesAllocCount); + if (length > 0) + mempool_resize(cifs_req_poolp, length + cifs_min_rcv, + GFP_KERNEL); +} + static int cifs_demultiplex_thread(void *p) { int length; struct TCP_Server_Info *server = p; unsigned int pdu_length, total_read; + char *buf = NULL, *bigbuf = NULL, *smallbuf = NULL; struct smb_hdr *smb_buffer = NULL; - struct smb_hdr *bigbuf = NULL; - struct smb_hdr *smallbuf = NULL; struct msghdr smb_msg; struct kvec iov; - struct socket *csocket = server->ssocket; - struct list_head *tmp, *tmp2; struct task_struct *task_to_wake = NULL; struct mid_q_entry *mid_entry; - char temp; bool isLargeBuf = false; - bool isMultiRsp; - int reconnect; + bool isMultiRsp = false; + int rc; current->flags |= PF_MEMALLOC; cFYI(1, "Demultiplex PID: %d", task_pid_nr(current)); @@ -351,35 +654,16 @@ cifs_demultiplex_thread(void *p) while (server->tcpStatus != CifsExiting) { if (try_to_freeze()) continue; - if (bigbuf == NULL) { - bigbuf = cifs_buf_get(); - if (!bigbuf) { - cERROR(1, "No memory for large SMB response"); - msleep(3000); - /* retry will check if exiting */ - continue; - } - } else if (isLargeBuf) { - /* we are reusing a dirty large buf, clear its start */ - memset(bigbuf, 0, sizeof(struct smb_hdr)); - } - if (smallbuf == NULL) { - smallbuf = cifs_small_buf_get(); - if (!smallbuf) { - cERROR(1, "No memory for SMB response"); - msleep(1000); - /* retry will check if exiting */ - continue; - } - /* beginning of smb buffer is cleared in our buf_get */ - } else /* if existing small buf clear beginning */ - memset(smallbuf, 0, sizeof(struct smb_hdr)); + if (!allocate_buffers(&bigbuf, &smallbuf, + sizeof(struct smb_hdr), isLargeBuf)) + continue; isLargeBuf = false; isMultiRsp = false; - smb_buffer = smallbuf; - iov.iov_base = smb_buffer; + smb_buffer = (struct smb_hdr *)smallbuf; + buf = smallbuf; + iov.iov_base = buf; iov.iov_len = 4; smb_msg.msg_control = NULL; smb_msg.msg_controllen = 0; @@ -393,158 +677,50 @@ incomplete_rcv: "Reconnecting...", server->hostname, (echo_retries * SMB_ECHO_INTERVAL / HZ)); cifs_reconnect(server); - csocket = server->ssocket; wake_up(&server->response_q); continue; } - length = - kernel_recvmsg(csocket, &smb_msg, - &iov, 1, pdu_length, 0 /* BB other flags? */); - - if (server->tcpStatus == CifsExiting) { + rc = read_from_socket(server, &smb_msg, &iov, pdu_length, + &total_read, true /* header read */); + if (rc == 3) + goto incomplete_rcv; + else if (rc == 2) break; - } else if (server->tcpStatus == CifsNeedReconnect) { - cFYI(1, "Reconnect after server stopped responding"); - cifs_reconnect(server); - cFYI(1, "call to reconnect done"); - csocket = server->ssocket; - continue; - } else if (length == -ERESTARTSYS || - length == -EAGAIN || - length == -EINTR) { - msleep(1); /* minimum sleep to prevent looping - allowing socket to clear and app threads to set - tcpStatus CifsNeedReconnect if server hung */ - if (pdu_length < 4) { - iov.iov_base = (4 - pdu_length) + - (char *)smb_buffer; - iov.iov_len = pdu_length; - smb_msg.msg_control = NULL; - smb_msg.msg_controllen = 0; - goto incomplete_rcv; - } else - continue; - } else if (length <= 0) { - cFYI(1, "Reconnect after unexpected peek error %d", - length); - cifs_reconnect(server); - csocket = server->ssocket; - wake_up(&server->response_q); + else if (rc == 1) continue; - } else if (length < pdu_length) { - cFYI(1, "requested %d bytes but only got %d bytes", - pdu_length, length); - pdu_length -= length; - msleep(1); - goto incomplete_rcv; - } - - /* The right amount was read from socket - 4 bytes */ - /* so we can now interpret the length field */ - /* 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 */ - temp = *((char *) smb_buffer); + /* + * The right amount was read from socket - 4 bytes, + * so we can now interpret the length field. + */ - /* Note that FC 1001 length is big endian on the wire, - but we convert it here so it is always manipulated - as host byte order */ + /* + * Note that RFC 1001 length is big endian on the wire, + * but we convert it here so it is always manipulated + * as host byte order. + */ pdu_length = be32_to_cpu(smb_buffer->smb_buf_length); cFYI(1, "rfc1002 length 0x%x", pdu_length+4); - - if (temp == (char) RFC1002_SESSION_KEEP_ALIVE) { - continue; - } else if (temp == (char)RFC1002_POSITIVE_SESSION_RESPONSE) { - cFYI(1, "Good RFC 1002 session rsp"); - continue; - } else if (temp == (char)RFC1002_NEGATIVE_SESSION_RESPONSE) { - /* we get this from Windows 98 instead of - an error on SMB negprot response */ - cFYI(1, "Negative RFC1002 Session Response Error 0x%x)", - pdu_length); - /* 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); - csocket = server->ssocket; - wake_up(&server->response_q); - continue; - } else if (temp != (char) 0) { - cERROR(1, "Unknown RFC 1002 frame"); - cifs_dump_mem(" Received Data: ", (char *)smb_buffer, - length); - cifs_reconnect(server); - csocket = server->ssocket; + if (!check_rfc1002_header(server, buf)) continue; - } - - /* else we have an SMB response */ - if ((pdu_length > CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4) || - (pdu_length < sizeof(struct smb_hdr) - 1 - 4)) { - cERROR(1, "Invalid size SMB length %d pdu_length %d", - length, pdu_length+4); - cifs_reconnect(server); - csocket = server->ssocket; - wake_up(&server->response_q); - continue; - } /* else length ok */ - reconnect = 0; - if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) { isLargeBuf = true; memcpy(bigbuf, smallbuf, 4); - smb_buffer = bigbuf; + smb_buffer = (struct smb_hdr *)bigbuf; + buf = bigbuf; } - length = 0; - iov.iov_base = 4 + (char *)smb_buffer; + + iov.iov_base = 4 + buf; iov.iov_len = pdu_length; - for (total_read = 0; total_read < pdu_length; - total_read += length) { - length = kernel_recvmsg(csocket, &smb_msg, &iov, 1, - pdu_length - total_read, 0); - if (server->tcpStatus == CifsExiting) { - /* then will exit */ - reconnect = 2; - break; - } else if (server->tcpStatus == CifsNeedReconnect) { - cifs_reconnect(server); - csocket = server->ssocket; - /* Reconnect wakes up rspns q */ - /* Now we will reread sock */ - reconnect = 1; - break; - } else if (length == -ERESTARTSYS || - length == -EAGAIN || - length == -EINTR) { - msleep(1); /* minimum sleep to prevent looping, - allowing socket to clear and app - threads to set tcpStatus - CifsNeedReconnect if server hung*/ - length = 0; - continue; - } else if (length <= 0) { - cERROR(1, "Received no data, expecting %d", - pdu_length - total_read); - cifs_reconnect(server); - csocket = server->ssocket; - reconnect = 1; - break; - } - } - if (reconnect == 2) + rc = read_from_socket(server, &smb_msg, &iov, pdu_length, + &total_read, false); + if (rc == 2) break; - else if (reconnect == 1) + else if (rc == 1) continue; total_read += 4; /* account for rfc1002 hdr */ @@ -562,75 +738,13 @@ incomplete_rcv: */ length = checkSMB(smb_buffer, smb_buffer->Mid, total_read); if (length != 0) - cifs_dump_mem("Bad SMB: ", smb_buffer, - min_t(unsigned int, total_read, 48)); + cifs_dump_mem("Bad SMB: ", buf, + min_t(unsigned int, total_read, 48)); - mid_entry = NULL; server->lstrp = jiffies; - 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 != smb_buffer->Mid || - mid_entry->midState != MID_REQUEST_SUBMITTED || - mid_entry->command != smb_buffer->Command) { - mid_entry = NULL; - continue; - } - - if (length == 0 && - check2ndT2(smb_buffer, server->maxBuf) > 0) { - /* We have a multipart transact2 resp */ - isMultiRsp = true; - if (mid_entry->resp_buf) { - /* merge response - fix up 1st*/ - length = coalesce_t2(smb_buffer, - mid_entry->resp_buf); - if (length > 0) { - length = 0; - mid_entry->multiRsp = true; - break; - } else { - /* all parts received or - * packet is malformed - */ - mid_entry->multiEnd = true; - goto multi_t2_fnd; - } - } else { - if (!isLargeBuf) { - /* - * FIXME: switch to already - * allocated largebuf? - */ - cERROR(1, "1st trans2 resp " - "needs bigbuf"); - } else { - /* Have first buffer */ - mid_entry->resp_buf = - smb_buffer; - mid_entry->largeBuf = true; - bigbuf = NULL; - } - } - break; - } - mid_entry->resp_buf = smb_buffer; - mid_entry->largeBuf = isLargeBuf; -multi_t2_fnd: - if (length == 0) - mid_entry->midState = MID_RESPONSE_RECEIVED; - else - mid_entry->midState = MID_RESPONSE_MALFORMED; -#ifdef CONFIG_CIFS_STATS2 - mid_entry->when_received = jiffies; -#endif - list_del_init(&mid_entry->qhead); - break; - } - spin_unlock(&GlobalMid_Lock); - + mid_entry = find_cifs_mid(server, smb_buffer, &length, + isLargeBuf, &isMultiRsp, &bigbuf); if (mid_entry != NULL) { mid_entry->callback(mid_entry); /* Was previous buf put in mpx struct for multi-rsp? */ @@ -648,7 +762,7 @@ multi_t2_fnd: !isMultiRsp) { cERROR(1, "No task to wake, unknown frame received! " "NumMids %d", atomic_read(&midCount)); - cifs_dump_mem("Received Data is: ", (char *)smb_buffer, + cifs_dump_mem("Received Data is: ", buf, sizeof(struct smb_hdr)); #ifdef CONFIG_CIFS_DEBUG2 cifs_dump_detail(smb_buffer); @@ -658,88 +772,13 @@ multi_t2_fnd: } } /* end while !EXITING */ - /* 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 */ - /* Note that cifs_max_pending is normally 50, but - can be set at module install time to as little as two */ - spin_lock(&GlobalMid_Lock); - if (atomic_read(&server->inFlight) >= cifs_max_pending) - atomic_set(&server->inFlight, cifs_max_pending - 1); - /* We do not want to set the max_pending too low or we - could end up with the counter going negative */ - spin_unlock(&GlobalMid_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(csocket); - server->ssocket = NULL; - } /* buffer usually freed in free_mid - need to free it here on exit */ cifs_buf_release(bigbuf); if (smallbuf) /* no sense logging a debug message if NULL */ cifs_small_buf_release(smallbuf); - if (!list_empty(&server->pending_mid_q)) { - struct list_head dispose_list; - - 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); - cFYI(1, "Clearing mid 0x%x", mid_entry->mid); - mid_entry->midState = 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); - cFYI(1, "Callback mid 0x%x", 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 */ - cFYI(1, "Wait for exit from demultiplex thread"); - 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); task_to_wake = xchg(&server->tsk, NULL); - kfree(server); - - length = atomic_dec_return(&tcpSesAllocCount); - if (length > 0) - mempool_resize(cifs_req_poolp, length + cifs_min_rcv, - GFP_KERNEL); + clean_demultiplex_info(server); /* if server->tsk was NULL then wait for a signal before exiting */ if (!task_to_wake) { @@ -3193,15 +3232,9 @@ mount_fail_check: else cifs_put_tcp_session(srvTcp); bdi_destroy(&cifs_sb->bdi); - goto out; } - /* volume_info->password is freed above when existing session found - (in which case it is not needed anymore) but when new sesion is created - the password ptr is put in the new session structure (in which case the - password will be freed at unmount time) */ out: - /* zero out password before freeing */ FreeXid(xid); return rc; } |