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[SCTP]: Cleanup nomem handling in the state functions.
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This patch cleans up the "nomem" conditions that may occur during the
processing by the state machine functions. In most cases we delay adding
side-effect commands until all memory allocations are done.

Signed-off-by: Vladislav Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Vladislav Yasevich authored and David S. Miller committed Sep 22, 2006
1 parent ac0b046 commit df7deeb
Showing 1 changed file with 86 additions and 73 deletions.
159 changes: 86 additions & 73 deletions net/sctp/sm_statefuns.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -187,10 +187,9 @@ sctp_disposition_t sctp_sf_do_4_C(const struct sctp_endpoint *ep,
*/
ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_SHUTDOWN_COMP,
0, 0, 0, GFP_ATOMIC);
if (!ev)
goto nomem;

sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
if (ev)
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
SCTP_ULPEVENT(ev));

/* Upon reception of the SHUTDOWN COMPLETE chunk the endpoint
* will verify that it is in SHUTDOWN-ACK-SENT state, if it is
Expand All @@ -215,9 +214,6 @@ sctp_disposition_t sctp_sf_do_4_C(const struct sctp_endpoint *ep,
sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());

return SCTP_DISPOSITION_DELETE_TCB;

nomem:
return SCTP_DISPOSITION_NOMEM;
}

/*
Expand Down Expand Up @@ -347,8 +343,6 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
GFP_ATOMIC))
goto nomem_init;

sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));

/* B) "Z" shall respond immediately with an INIT ACK chunk. */

/* If there are errors need to be reported for unknown parameters,
Expand All @@ -360,11 +354,11 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
sizeof(sctp_chunkhdr_t);

if (sctp_assoc_set_bind_addr_from_ep(new_asoc, GFP_ATOMIC) < 0)
goto nomem_ack;
goto nomem_init;

repl = sctp_make_init_ack(new_asoc, chunk, GFP_ATOMIC, len);
if (!repl)
goto nomem_ack;
goto nomem_init;

/* If there are errors need to be reported for unknown parameters,
* include them in the outgoing INIT ACK as "Unrecognized parameter"
Expand All @@ -388,6 +382,8 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,
sctp_chunk_free(err_chunk);
}

sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));

sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));

/*
Expand All @@ -400,12 +396,11 @@ sctp_disposition_t sctp_sf_do_5_1B_init(const struct sctp_endpoint *ep,

return SCTP_DISPOSITION_DELETE_TCB;

nomem_ack:
if (err_chunk)
sctp_chunk_free(err_chunk);
nomem_init:
sctp_association_free(new_asoc);
nomem:
if (err_chunk)
sctp_chunk_free(err_chunk);
return SCTP_DISPOSITION_NOMEM;
}

Expand Down Expand Up @@ -600,7 +595,7 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,
struct sctp_association *new_asoc;
sctp_init_chunk_t *peer_init;
struct sctp_chunk *repl;
struct sctp_ulpevent *ev;
struct sctp_ulpevent *ev, *ai_ev = NULL;
int error = 0;
struct sctp_chunk *err_chk_p;

Expand Down Expand Up @@ -659,20 +654,10 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,
};
}

sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
SCTP_STATE(SCTP_STATE_ESTABLISHED));
SCTP_INC_STATS(SCTP_MIB_CURRESTAB);
SCTP_INC_STATS(SCTP_MIB_PASSIVEESTABS);
sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL());

if (new_asoc->autoclose)
sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));

sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL());

/* Re-build the bind address for the association is done in
/* Delay state machine commands until later.
*
* Re-build the bind address for the association is done in
* the sctp_unpack_cookie() already.
*/
/* This is a brand-new association, so these are not yet side
Expand All @@ -687,9 +672,7 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,

repl = sctp_make_cookie_ack(new_asoc, chunk);
if (!repl)
goto nomem_repl;

sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
goto nomem_init;

/* RFC 2960 5.1 Normal Establishment of an Association
*
Expand All @@ -704,28 +687,53 @@ sctp_disposition_t sctp_sf_do_5_1D_ce(const struct sctp_endpoint *ep,
if (!ev)
goto nomem_ev;

sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));

/* Sockets API Draft Section 5.3.1.6
* When a peer sends a Adaption Layer Indication parameter , SCTP
* delivers this notification to inform the application that of the
* peers requested adaption layer.
*/
if (new_asoc->peer.adaption_ind) {
ev = sctp_ulpevent_make_adaption_indication(new_asoc,
ai_ev = sctp_ulpevent_make_adaption_indication(new_asoc,
GFP_ATOMIC);
if (!ev)
goto nomem_ev;
if (!ai_ev)
goto nomem_aiev;
}

/* Add all the state machine commands now since we've created
* everything. This way we don't introduce memory corruptions
* during side-effect processing and correclty count established
* associations.
*/
sctp_add_cmd_sf(commands, SCTP_CMD_NEW_ASOC, SCTP_ASOC(new_asoc));
sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
SCTP_STATE(SCTP_STATE_ESTABLISHED));
SCTP_INC_STATS(SCTP_MIB_CURRESTAB);
SCTP_INC_STATS(SCTP_MIB_PASSIVEESTABS);
sctp_add_cmd_sf(commands, SCTP_CMD_HB_TIMERS_START, SCTP_NULL());

if (new_asoc->autoclose)
sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_START,
SCTP_TO(SCTP_EVENT_TIMEOUT_AUTOCLOSE));

sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL());

/* This will send the COOKIE ACK */
sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));

/* Queue the ASSOC_CHANGE event */
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));

/* Send up the Adaptation Layer Indication event */
if (ai_ev)
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
SCTP_ULPEVENT(ev));
}
SCTP_ULPEVENT(ai_ev));

return SCTP_DISPOSITION_CONSUME;

nomem_aiev:
sctp_ulpevent_free(ev);
nomem_ev:
sctp_chunk_free(repl);
nomem_repl:
nomem_init:
sctp_association_free(new_asoc);
nomem:
Expand Down Expand Up @@ -1360,10 +1368,8 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
if (!sctp_process_init(new_asoc, chunk->chunk_hdr->type,
sctp_source(chunk),
(sctp_init_chunk_t *)chunk->chunk_hdr,
GFP_ATOMIC)) {
retval = SCTP_DISPOSITION_NOMEM;
goto nomem_init;
}
GFP_ATOMIC))
goto nomem;

/* Make sure no new addresses are being added during the
* restart. Do not do this check for COOKIE-WAIT state,
Expand All @@ -1374,7 +1380,7 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
if (!sctp_sf_check_restart_addrs(new_asoc, asoc, chunk,
commands)) {
retval = SCTP_DISPOSITION_CONSUME;
goto cleanup_asoc;
goto nomem_retval;
}
}

Expand Down Expand Up @@ -1430,17 +1436,17 @@ static sctp_disposition_t sctp_sf_do_unexpected_init(
sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
retval = SCTP_DISPOSITION_CONSUME;

return retval;

nomem:
retval = SCTP_DISPOSITION_NOMEM;
nomem_retval:
if (new_asoc)
sctp_association_free(new_asoc);
cleanup:
if (err_chunk)
sctp_chunk_free(err_chunk);
return retval;
nomem:
retval = SCTP_DISPOSITION_NOMEM;
goto cleanup;
nomem_init:
cleanup_asoc:
sctp_association_free(new_asoc);
goto cleanup;
}

/*
Expand Down Expand Up @@ -1611,15 +1617,10 @@ static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep,
*/
sctp_add_cmd_sf(commands, SCTP_CMD_PURGE_OUTQUEUE, SCTP_NULL());

/* Update the content of current association. */
sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc));

repl = sctp_make_cookie_ack(new_asoc, chunk);
if (!repl)
goto nomem;

sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));

/* Report association restart to upper layer. */
ev = sctp_ulpevent_make_assoc_change(asoc, 0, SCTP_RESTART, 0,
new_asoc->c.sinit_num_ostreams,
Expand All @@ -1628,6 +1629,9 @@ static sctp_disposition_t sctp_sf_do_dupcook_a(const struct sctp_endpoint *ep,
if (!ev)
goto nomem_ev;

/* Update the content of current association. */
sctp_add_cmd_sf(commands, SCTP_CMD_UPDATE_ASSOC, SCTP_ASOC(new_asoc));
sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));
return SCTP_DISPOSITION_CONSUME;

Expand Down Expand Up @@ -1751,7 +1755,7 @@ static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep,
sctp_cmd_seq_t *commands,
struct sctp_association *new_asoc)
{
struct sctp_ulpevent *ev = NULL;
struct sctp_ulpevent *ev = NULL, *ai_ev = NULL;
struct sctp_chunk *repl;

/* Clarification from Implementor's Guide:
Expand All @@ -1778,29 +1782,25 @@ static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep,
* SCTP user upon reception of a valid COOKIE
* ECHO chunk.
*/
ev = sctp_ulpevent_make_assoc_change(new_asoc, 0,
ev = sctp_ulpevent_make_assoc_change(asoc, 0,
SCTP_COMM_UP, 0,
new_asoc->c.sinit_num_ostreams,
new_asoc->c.sinit_max_instreams,
asoc->c.sinit_num_ostreams,
asoc->c.sinit_max_instreams,
GFP_ATOMIC);
if (!ev)
goto nomem;
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
SCTP_ULPEVENT(ev));

/* Sockets API Draft Section 5.3.1.6
* When a peer sends a Adaption Layer Indication parameter,
* SCTP delivers this notification to inform the application
* that of the peers requested adaption layer.
*/
if (new_asoc->peer.adaption_ind) {
ev = sctp_ulpevent_make_adaption_indication(new_asoc,
if (asoc->peer.adaption_ind) {
ai_ev = sctp_ulpevent_make_adaption_indication(asoc,
GFP_ATOMIC);
if (!ev)
if (!ai_ev)
goto nomem;

sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
SCTP_ULPEVENT(ev));
}
}
sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL());
Expand All @@ -1809,12 +1809,21 @@ static sctp_disposition_t sctp_sf_do_dupcook_d(const struct sctp_endpoint *ep,
if (!repl)
goto nomem;

if (ev)
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
SCTP_ULPEVENT(ev));
if (ai_ev)
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP,
SCTP_ULPEVENT(ai_ev));

sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(repl));
sctp_add_cmd_sf(commands, SCTP_CMD_TRANSMIT, SCTP_NULL());

return SCTP_DISPOSITION_CONSUME;

nomem:
if (ai_ev)
sctp_ulpevent_free(ai_ev);
if (ev)
sctp_ulpevent_free(ev);
return SCTP_DISPOSITION_NOMEM;
Expand Down Expand Up @@ -3019,7 +3028,6 @@ sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep,
if (!sctp_chunk_length_valid(chunk, sizeof(sctp_chunkhdr_t)))
return sctp_sf_violation_chunklen(ep, asoc, type, arg,
commands);

/* 10.2 H) SHUTDOWN COMPLETE notification
*
* When SCTP completes the shutdown procedures (section 9.2) this
Expand All @@ -3030,6 +3038,14 @@ sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep,
if (!ev)
goto nomem;

/* ...send a SHUTDOWN COMPLETE chunk to its peer, */
reply = sctp_make_shutdown_complete(asoc, chunk);
if (!reply)
goto nomem_chunk;

/* Do all the commands now (after allocation), so that we
* have consistent state if memory allocation failes
*/
sctp_add_cmd_sf(commands, SCTP_CMD_EVENT_ULP, SCTP_ULPEVENT(ev));

/* Upon the receipt of the SHUTDOWN ACK, the SHUTDOWN sender shall
Expand All @@ -3041,11 +3057,6 @@ sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep,
sctp_add_cmd_sf(commands, SCTP_CMD_TIMER_STOP,
SCTP_TO(SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD));

/* ...send a SHUTDOWN COMPLETE chunk to its peer, */
reply = sctp_make_shutdown_complete(asoc, chunk);
if (!reply)
goto nomem;

sctp_add_cmd_sf(commands, SCTP_CMD_NEW_STATE,
SCTP_STATE(SCTP_STATE_CLOSED));
SCTP_INC_STATS(SCTP_MIB_SHUTDOWNS);
Expand All @@ -3056,6 +3067,8 @@ sctp_disposition_t sctp_sf_do_9_2_final(const struct sctp_endpoint *ep,
sctp_add_cmd_sf(commands, SCTP_CMD_DELETE_TCB, SCTP_NULL());
return SCTP_DISPOSITION_DELETE_TCB;

nomem_chunk:
sctp_ulpevent_free(ev);
nomem:
return SCTP_DISPOSITION_NOMEM;
}
Expand Down

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