From ba0166708ef4da7eeb61dd92bbba4d5a749d6561 Mon Sep 17 00:00:00 2001 From: Wei Yongjun Date: Tue, 30 Sep 2008 05:32:24 -0700 Subject: [PATCH] sctp: Fix kernel panic while process protocol violation parameter Since call to function sctp_sf_abort_violation() need paramter 'arg' with 'struct sctp_chunk' type, it will read the chunk type and chunk length from the chunk_hdr member of chunk. But call to sctp_sf_violation_paramlen() always with 'struct sctp_paramhdr' type's parameter, it will be passed to sctp_sf_abort_violation(). This may cause kernel panic. sctp_sf_violation_paramlen() |-- sctp_sf_abort_violation() |-- sctp_make_abort_violation() This patch fixed this problem. This patch also fix two place which called sctp_sf_violation_paramlen() with wrong paramter type. Signed-off-by: Wei Yongjun Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- include/net/sctp/sm.h | 3 +++ net/sctp/sm_make_chunk.c | 37 ++++++++++++++++++++----------- net/sctp/sm_statefuns.c | 48 +++++++++++++++++++++++++++++++--------- 3 files changed, 64 insertions(+), 24 deletions(-) diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h index 24811732bdb..029a54a0239 100644 --- a/include/net/sctp/sm.h +++ b/include/net/sctp/sm.h @@ -227,6 +227,9 @@ struct sctp_chunk *sctp_make_abort_violation(const struct sctp_association *, const struct sctp_chunk *, const __u8 *, const size_t ); +struct sctp_chunk *sctp_make_violation_paramlen(const struct sctp_association *, + const struct sctp_chunk *, + struct sctp_paramhdr *); struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *, const struct sctp_transport *, const void *payload, diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c index b599cbba4fb..d68869f966c 100644 --- a/net/sctp/sm_make_chunk.c +++ b/net/sctp/sm_make_chunk.c @@ -1012,6 +1012,29 @@ end: return retval; } +struct sctp_chunk *sctp_make_violation_paramlen( + const struct sctp_association *asoc, + const struct sctp_chunk *chunk, + struct sctp_paramhdr *param) +{ + struct sctp_chunk *retval; + static const char error[] = "The following parameter had invalid length:"; + size_t payload_len = sizeof(error) + sizeof(sctp_errhdr_t) + + sizeof(sctp_paramhdr_t); + + retval = sctp_make_abort(asoc, chunk, payload_len); + if (!retval) + goto nodata; + + sctp_init_cause(retval, SCTP_ERROR_PROTO_VIOLATION, + sizeof(error) + sizeof(sctp_paramhdr_t)); + sctp_addto_chunk(retval, sizeof(error), error); + sctp_addto_param(retval, sizeof(sctp_paramhdr_t), param); + +nodata: + return retval; +} + /* Make a HEARTBEAT chunk. */ struct sctp_chunk *sctp_make_heartbeat(const struct sctp_association *asoc, const struct sctp_transport *transport, @@ -1782,11 +1805,6 @@ static int sctp_process_inv_paramlength(const struct sctp_association *asoc, const struct sctp_chunk *chunk, struct sctp_chunk **errp) { - static const char error[] = "The following parameter had invalid length:"; - size_t payload_len = WORD_ROUND(sizeof(error)) + - sizeof(sctp_paramhdr_t); - - /* This is a fatal error. Any accumulated non-fatal errors are * not reported. */ @@ -1794,14 +1812,7 @@ static int sctp_process_inv_paramlength(const struct sctp_association *asoc, sctp_chunk_free(*errp); /* Create an error chunk and fill it in with our payload. */ - *errp = sctp_make_op_error_space(asoc, chunk, payload_len); - - if (*errp) { - sctp_init_cause(*errp, SCTP_ERROR_PROTO_VIOLATION, - sizeof(error) + sizeof(sctp_paramhdr_t)); - sctp_addto_chunk(*errp, sizeof(error), error); - sctp_addto_param(*errp, sizeof(sctp_paramhdr_t), param); - } + *errp = sctp_make_violation_paramlen(asoc, chunk, param); return 0; } diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 8848d329aa2..7c622af2ce5 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -119,7 +119,7 @@ static sctp_disposition_t sctp_sf_violation_paramlen( const struct sctp_endpoint *ep, const struct sctp_association *asoc, const sctp_subtype_t type, - void *arg, + void *arg, void *ext, sctp_cmd_seq_t *commands); static sctp_disposition_t sctp_sf_violation_ctsn( @@ -3425,7 +3425,7 @@ sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep, addr_param = (union sctp_addr_param *)hdr->params; length = ntohs(addr_param->p.length); if (length < sizeof(sctp_paramhdr_t)) - return sctp_sf_violation_paramlen(ep, asoc, type, + return sctp_sf_violation_paramlen(ep, asoc, type, arg, (void *)addr_param, commands); /* Verify the ASCONF chunk before processing it. */ @@ -3433,8 +3433,8 @@ sctp_disposition_t sctp_sf_do_asconf(const struct sctp_endpoint *ep, (sctp_paramhdr_t *)((void *)addr_param + length), (void *)chunk->chunk_end, &err_param)) - return sctp_sf_violation_paramlen(ep, asoc, type, - (void *)&err_param, commands); + return sctp_sf_violation_paramlen(ep, asoc, type, arg, + (void *)err_param, commands); /* ADDIP 5.2 E1) Compare the value of the serial number to the value * the endpoint stored in a new association variable @@ -3542,8 +3542,8 @@ sctp_disposition_t sctp_sf_do_asconf_ack(const struct sctp_endpoint *ep, (sctp_paramhdr_t *)addip_hdr->params, (void *)asconf_ack->chunk_end, &err_param)) - return sctp_sf_violation_paramlen(ep, asoc, type, - (void *)&err_param, commands); + return sctp_sf_violation_paramlen(ep, asoc, type, arg, + (void *)err_param, commands); if (last_asconf) { addip_hdr = (sctp_addiphdr_t *)last_asconf->subh.addip_hdr; @@ -4240,12 +4240,38 @@ static sctp_disposition_t sctp_sf_violation_paramlen( const struct sctp_endpoint *ep, const struct sctp_association *asoc, const sctp_subtype_t type, - void *arg, - sctp_cmd_seq_t *commands) { - static const char err_str[] = "The following parameter had invalid length:"; + void *arg, void *ext, + sctp_cmd_seq_t *commands) +{ + struct sctp_chunk *chunk = arg; + struct sctp_paramhdr *param = ext; + struct sctp_chunk *abort = NULL; - return sctp_sf_abort_violation(ep, asoc, arg, commands, err_str, - sizeof(err_str)); + if (sctp_auth_recv_cid(SCTP_CID_ABORT, asoc)) + goto discard; + + /* Make the abort chunk. */ + abort = sctp_make_violation_paramlen(asoc, chunk, param); + if (!abort) + goto nomem; + + sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(abort)); + SCTP_INC_STATS(SCTP_MIB_OUTCTRLCHUNKS); + + sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR, + SCTP_ERROR(ECONNABORTED)); + sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED, + SCTP_PERR(SCTP_ERROR_PROTO_VIOLATION)); + SCTP_DEC_STATS(SCTP_MIB_CURRESTAB); + +discard: + sctp_sf_pdiscard(ep, asoc, SCTP_ST_CHUNK(0), arg, commands); + + SCTP_INC_STATS(SCTP_MIB_ABORTEDS); + + return SCTP_DISPOSITION_ABORT; +nomem: + return SCTP_DISPOSITION_NOMEM; } /* Handle a protocol violation when the peer trying to advance the -- 2.20.1