diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h index 1ab33eb71d95..17afb0fbcaed 100644 --- a/fs/cifs/cifsglob.h +++ b/fs/cifs/cifsglob.h @@ -654,7 +654,7 @@ static inline void free_dfs_info_array(struct dfs_info3_param *param, #define MID_REQUEST_SUBMITTED 2 #define MID_RESPONSE_RECEIVED 4 #define MID_RETRY_NEEDED 8 /* session closed while this request out */ -#define MID_NO_RESP_NEEDED 0x10 +#define MID_RESPONSE_MALFORMED 0x10 /* Types of response buffer returned from SendReceive2 */ #define CIFS_NO_BUFFER 0 /* Response buffer not returned */ diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 161f24ca4f6e..8d6c17ab593d 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -586,11 +586,20 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server) total_read += 4; /* account for rfc1002 hdr */ dump_smb(smb_buffer, total_read); - if (checkSMB(smb_buffer, smb_buffer->Mid, 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 = checkSMB(smb_buffer, smb_buffer->Mid, total_read); + if (length != 0) cifs_dump_mem("Bad SMB: ", smb_buffer, - total_read < 48 ? total_read : 48); - continue; - } + min_t(unsigned int, total_read, 48)); mid_entry = NULL; server->lstrp = jiffies; @@ -602,7 +611,8 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server) if ((mid_entry->mid == smb_buffer->Mid) && (mid_entry->midState == MID_REQUEST_SUBMITTED) && (mid_entry->command == smb_buffer->Command)) { - if (check2ndT2(smb_buffer,server->maxBuf) > 0) { + if (length == 0 && + check2ndT2(smb_buffer, server->maxBuf) > 0) { /* We have a multipart transact2 resp */ isMultiRsp = true; if (mid_entry->resp_buf) { @@ -637,7 +647,12 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server) mid_entry->resp_buf = smb_buffer; mid_entry->largeBuf = isLargeBuf; multi_t2_fnd: - mid_entry->midState = MID_RESPONSE_RECEIVED; + 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 @@ -658,6 +673,9 @@ cifs_demultiplex_thread(struct TCP_Server_Info *server) else smallbuf = NULL; } + } else if (length != 0) { + /* response sanity checks failed */ + continue; } else if (!is_valid_oplock_break(smb_buffer, server) && !isMultiRsp) { cERROR(1, "No task to wake, unknown frame received! " diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c index fbc5aace54b1..46d8756f2b24 100644 --- a/fs/cifs/transport.c +++ b/fs/cifs/transport.c @@ -457,6 +457,9 @@ sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server) case MID_RETRY_NEEDED: rc = -EAGAIN; break; + case MID_RESPONSE_MALFORMED: + rc = -EIO; + break; default: cERROR(1, "%s: invalid mid state mid=%d state=%d", __func__, mid->mid, mid->midState);