d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Make sequence numbers checks more strict.

Browse Source 
While we don't support MCS, hole in received sequence numbers may mean
only PDU loss.  While we don't support lost PDU recovery, terminate the
connection to avoid stuck commands.

While there, improve handling of sequence numbers wrap after 2^32 PDUs.

MFC after:	2 weeks
This commit is contained in:
mav 2014-12-17 15:13:21 +00:00
parent df55c61fa5
commit fe9781bb78
8 changed files with 81 additions and 44 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

48
sys/cam/ctl/ctl_frontend_iscsi.c
View File

@ -233,19 +233,34 @@ cfiscsi_pdu_update_cmdsn(const struct icl_pdu *request)
}
#endif
/*
* The target MUST silently ignore any non-immediate command outside
* of this range.
*/
if (cmdsn < cs->cs_cmdsn || cmdsn > cs->cs_cmdsn + maxcmdsn_delta) {
CFISCSI_SESSION_UNLOCK(cs);
CFISCSI_SESSION_WARN(cs, "received PDU with CmdSN %d, "
"while expected CmdSN was %d", cmdsn, cs->cs_cmdsn);
return (true);
}
if ((request->ip_bhs->bhs_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0) {
/*
* The target MUST silently ignore any non-immediate command
* outside of this range.
*/
if (ISCSI_SNLT(cmdsn, cs->cs_cmdsn) ||
ISCSI_SNGT(cmdsn, cs->cs_cmdsn + maxcmdsn_delta)) {
CFISCSI_SESSION_UNLOCK(cs);
CFISCSI_SESSION_WARN(cs, "received PDU with CmdSN %u, "
"while expected %u", cmdsn, cs->cs_cmdsn);
return (true);
}
if ((request->ip_bhs->bhs_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0)
/*
* We don't support multiple connections now, so any
* discontinuity in CmdSN means lost PDUs. Since we don't
* support PDU retransmission -- terminate the connection.
*/
if (cmdsn != cs->cs_cmdsn) {
CFISCSI_SESSION_UNLOCK(cs);
CFISCSI_SESSION_WARN(cs, "received PDU with CmdSN %u, "
"while expected %u; dropping connection",
cmdsn, cs->cs_cmdsn);
cfiscsi_session_terminate(cs);
return (true);
}
cs->cs_cmdsn++;
}
CFISCSI_SESSION_UNLOCK(cs);
@ -892,6 +907,16 @@ cfiscsi_pdu_handle_data_out(struct icl_pdu *request)
return;
}
if (cdw->cdw_datasn != ntohl(bhsdo->bhsdo_datasn)) {
CFISCSI_SESSION_WARN(cs, "received Data-Out PDU with "
"DataSN %u, while expected %u; dropping connection",
ntohl(bhsdo->bhsdo_datasn), cdw->cdw_datasn);
icl_pdu_free(request);
cfiscsi_session_terminate(cs);
return;
}
cdw->cdw_datasn++;
io = cdw->cdw_ctl_io;
KASSERT((io->io_hdr.flags & CTL_FLAG_DATA_MASK) != CTL_FLAG_DATA_IN,
("CTL_FLAG_DATA_IN"));
@ -2650,6 +2675,7 @@ cfiscsi_datamove_out(union ctl_io *io)
cdw->cdw_target_transfer_tag = target_transfer_tag;
cdw->cdw_initiator_task_tag = bhssc->bhssc_initiator_task_tag;
cdw->cdw_r2t_end = io->scsiio.kern_data_len;
cdw->cdw_datasn = 0;
/* Set initial data pointer for the CDW respecting ext_data_filled. */
if (io->scsiio.kern_sg_entries > 0) {

1
sys/cam/ctl/ctl_frontend_iscsi.h
View File

@ -58,6 +58,7 @@ struct cfiscsi_data_wait {
char *cdw_sg_addr;
size_t cdw_sg_len;
uint32_t cdw_r2t_end;
uint32_t cdw_datasn;
};
#define CFISCSI_SESSION_STATE_INVALID 0

49
sys/dev/iscsi/iscsi.c
View File

@ -192,7 +192,7 @@ iscsi_pdu_prepare(struct icl_pdu *request)
* Data-Out PDU does not contain CmdSN.
*/
if (bhssc->bhssc_opcode != ISCSI_BHS_OPCODE_SCSI_DATA_OUT) {
if (is->is_cmdsn > is->is_maxcmdsn &&
if (ISCSI_SNGT(is->is_cmdsn, is->is_maxcmdsn) &&
(bhssc->bhssc_opcode & ISCSI_BHS_OPCODE_IMMEDIATE) == 0) {
/*
* Current MaxCmdSN prevents us from sending any more
@ -201,8 +201,10 @@ iscsi_pdu_prepare(struct icl_pdu *request)
* or by maintenance thread.
*/
#if 0
ISCSI_SESSION_DEBUG(is, "postponing send, CmdSN %d, ExpCmdSN %d, MaxCmdSN %d, opcode 0x%x",
is->is_cmdsn, is->is_expcmdsn, is->is_maxcmdsn, bhssc->bhssc_opcode);
ISCSI_SESSION_DEBUG(is, "postponing send, CmdSN %u, "
"ExpCmdSN %u, MaxCmdSN %u, opcode 0x%x",
is->is_cmdsn, is->is_expcmdsn, is->is_maxcmdsn,
bhssc->bhssc_opcode);
#endif
return (true);
}
@ -611,7 +613,7 @@ iscsi_pdu_update_statsn(const struct icl_pdu *response)
{
const struct iscsi_bhs_data_in *bhsdi;
struct iscsi_session *is;
uint32_t expcmdsn, maxcmdsn;
uint32_t expcmdsn, maxcmdsn, statsn;
is = PDU_SESSION(response);
@ -630,26 +632,27 @@ iscsi_pdu_update_statsn(const struct icl_pdu *response)
*/
if (bhsdi->bhsdi_opcode != ISCSI_BHS_OPCODE_SCSI_DATA_IN ||
(bhsdi->bhsdi_flags & BHSDI_FLAGS_S) != 0) {
if (ntohl(bhsdi->bhsdi_statsn) < is->is_statsn) {
ISCSI_SESSION_WARN(is,
"PDU StatSN %d >= session StatSN %d, opcode 0x%x",
is->is_statsn, ntohl(bhsdi->bhsdi_statsn),
bhsdi->bhsdi_opcode);
statsn = ntohl(bhsdi->bhsdi_statsn);
if (statsn != is->is_statsn && statsn != (is->is_statsn + 1)) {
/* XXX: This is normal situation for MCS */
ISCSI_SESSION_WARN(is, "PDU 0x%x StatSN %u != "
"session ExpStatSN %u (or + 1); reconnecting",
bhsdi->bhsdi_opcode, statsn, is->is_statsn);
iscsi_session_reconnect(is);
}
is->is_statsn = ntohl(bhsdi->bhsdi_statsn);
if (ISCSI_SNGT(statsn, is->is_statsn))
is->is_statsn = statsn;
}
expcmdsn = ntohl(bhsdi->bhsdi_expcmdsn);
maxcmdsn = ntohl(bhsdi->bhsdi_maxcmdsn);
/*
* XXX: Compare using Serial Arithmetic Sense.
*/
if (maxcmdsn + 1 < expcmdsn) {
ISCSI_SESSION_DEBUG(is, "PDU MaxCmdSN %d + 1 < PDU ExpCmdSN %d; ignoring",
if (ISCSI_SNLT(maxcmdsn + 1, expcmdsn)) {
ISCSI_SESSION_DEBUG(is,
"PDU MaxCmdSN %u + 1 < PDU ExpCmdSN %u; ignoring",
maxcmdsn, expcmdsn);
} else {
if (maxcmdsn > is->is_maxcmdsn) {
if (ISCSI_SNGT(maxcmdsn, is->is_maxcmdsn)) {
is->is_maxcmdsn = maxcmdsn;
/*
@ -658,15 +661,19 @@ iscsi_pdu_update_statsn(const struct icl_pdu *response)
*/
if (!STAILQ_EMPTY(&is->is_postponed))
cv_signal(&is->is_maintenance_cv);
} else if (maxcmdsn < is->is_maxcmdsn) {
ISCSI_SESSION_DEBUG(is, "PDU MaxCmdSN %d < session MaxCmdSN %d; ignoring",
} else if (ISCSI_SNLT(maxcmdsn, is->is_maxcmdsn)) {
/* XXX: This is normal situation for MCS */
ISCSI_SESSION_DEBUG(is,
"PDU MaxCmdSN %u < session MaxCmdSN %u; ignoring",
maxcmdsn, is->is_maxcmdsn);
}
if (expcmdsn > is->is_expcmdsn) {
if (ISCSI_SNGT(expcmdsn, is->is_expcmdsn)) {
is->is_expcmdsn = expcmdsn;
} else if (expcmdsn < is->is_expcmdsn) {
ISCSI_SESSION_DEBUG(is, "PDU ExpCmdSN %d < session ExpCmdSN %d; ignoring",
} else if (ISCSI_SNLT(expcmdsn, is->is_expcmdsn)) {
/* XXX: This is normal situation for MCS */
ISCSI_SESSION_DEBUG(is,
"PDU ExpCmdSN %u < session ExpCmdSN %u; ignoring",
expcmdsn, is->is_expcmdsn);
}
}

3
sys/dev/iscsi/iscsi_proto.h
View File

@ -38,6 +38,9 @@
#define __CTASSERT(x, y) typedef char __assert_ ## y [(x) ? 1 : -1]
#endif
#define ISCSI_SNGT(x, y) ((int32_t)(x) - (int32_t)(y) > 0)
#define ISCSI_SNLT(x, y) ((int32_t)(x) - (int32_t)(y) < 0)
#define ISCSI_BHS_SIZE 48
#define ISCSI_HEADER_DIGEST_SIZE 4
#define ISCSI_DATA_DIGEST_SIZE 4

12
usr.sbin/ctld/discovery.c
View File

@ -65,13 +65,13 @@ text_receive(struct connection *conn)
*/
if ((bhstr->bhstr_flags & BHSTR_FLAGS_CONTINUE) != 0)
log_errx(1, "received Text PDU with unsupported \"C\" flag");
if (ntohl(bhstr->bhstr_cmdsn) < conn->conn_cmdsn) {
if (ISCSI_SNLT(ntohl(bhstr->bhstr_cmdsn), conn->conn_cmdsn)) {
log_errx(1, "received Text PDU with decreasing CmdSN: "
"was %d, is %d", conn->conn_cmdsn, ntohl(bhstr->bhstr_cmdsn));
"was %u, is %u", conn->conn_cmdsn, ntohl(bhstr->bhstr_cmdsn));
}
if (ntohl(bhstr->bhstr_expstatsn) != conn->conn_statsn) {
log_errx(1, "received Text PDU with wrong StatSN: "
"is %d, should be %d", ntohl(bhstr->bhstr_expstatsn),
"is %u, should be %u", ntohl(bhstr->bhstr_expstatsn),
conn->conn_statsn);
}
conn->conn_cmdsn = ntohl(bhstr->bhstr_cmdsn);
@ -120,14 +120,14 @@ logout_receive(struct connection *conn)
if ((bhslr->bhslr_reason & 0x7f) != BHSLR_REASON_CLOSE_SESSION)
log_debugx("received Logout PDU with invalid reason 0x%x; "
"continuing anyway", bhslr->bhslr_reason & 0x7f);
if (ntohl(bhslr->bhslr_cmdsn) < conn->conn_cmdsn) {
if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
log_errx(1, "received Logout PDU with decreasing CmdSN: "
"was %d, is %d", conn->conn_cmdsn,
"was %u, is %u", conn->conn_cmdsn,
ntohl(bhslr->bhslr_cmdsn));
}
if (ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
log_errx(1, "received Logout PDU with wrong StatSN: "
"is %d, should be %d", ntohl(bhslr->bhslr_expstatsn),
"is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
conn->conn_statsn);
}
conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);

6
usr.sbin/ctld/login.c
View File

@ -127,17 +127,17 @@ login_receive(struct connection *conn, bool initial)
log_errx(1, "received Login PDU with unsupported "
"Version-min 0x%x", bhslr->bhslr_version_min);
}
if (ntohl(bhslr->bhslr_cmdsn) < conn->conn_cmdsn) {
if (ISCSI_SNLT(ntohl(bhslr->bhslr_cmdsn), conn->conn_cmdsn)) {
login_send_error(request, 0x02, 0x05);
log_errx(1, "received Login PDU with decreasing CmdSN: "
"was %d, is %d", conn->conn_cmdsn,
"was %u, is %u", conn->conn_cmdsn,
ntohl(bhslr->bhslr_cmdsn));
}
if (initial == false &&
ntohl(bhslr->bhslr_expstatsn) != conn->conn_statsn) {
login_send_error(request, 0x02, 0x05);
log_errx(1, "received Login PDU with wrong ExpStatSN: "
"is %d, should be %d", ntohl(bhslr->bhslr_expstatsn),
"is %u, should be %u", ntohl(bhslr->bhslr_expstatsn),
conn->conn_statsn);
}
conn->conn_cmdsn = ntohl(bhslr->bhslr_cmdsn);

4
usr.sbin/iscsid/discovery.c
View File

@ -66,7 +66,7 @@ text_receive(struct connection *conn)
log_errx(1, "received Text PDU with unsupported \"C\" flag");
if (ntohl(bhstr->bhstr_statsn) != conn->conn_statsn + 1) {
log_errx(1, "received Text PDU with wrong StatSN: "
"is %d, should be %d", ntohl(bhstr->bhstr_statsn),
"is %u, should be %u", ntohl(bhstr->bhstr_statsn),
conn->conn_statsn + 1);
}
conn->conn_statsn = ntohl(bhstr->bhstr_statsn);
@ -112,7 +112,7 @@ logout_receive(struct connection *conn)
ntohs(bhslr->bhslr_response));
if (ntohl(bhslr->bhslr_statsn) != conn->conn_statsn + 1) {
log_errx(1, "received Logout PDU with wrong StatSN: "
"is %d, should be %d", ntohl(bhslr->bhslr_statsn),
"is %u, should be %u", ntohl(bhslr->bhslr_statsn),
conn->conn_statsn + 1);
}
conn->conn_statsn = ntohl(bhslr->bhslr_statsn);

2
usr.sbin/iscsid/login.c
View File

@ -257,7 +257,7 @@ login_receive(struct connection *conn)
* to be bug in NetBSD iSCSI target.
*/
log_warnx("received Login PDU with wrong StatSN: "
"is %d, should be %d", ntohl(bhslr->bhslr_statsn),
"is %u, should be %u", ntohl(bhslr->bhslr_statsn),
conn->conn_statsn + 1);
}
conn->conn_tsih = ntohs(bhslr->bhslr_tsih);