From: Richard Mudgett Date: Mon, 24 Sep 2012 20:44:27 +0000 (+0000) Subject: Fix potential reentrancy problems in chan_sip. X-Git-Tag: 10.10.0-rc1~44 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=de75d22add23889071c30e3d1e77bac8bd1b7f42;p=thirdparty%2Fasterisk.git Fix potential reentrancy problems in chan_sip. Asterisk v1.8 and later was not as vulnerable to this issue. * Made find_call() lock each private as it processes the found dialogs. (Primary cause of ABE-2876) * Made the other functions that traverse the dialogs container lock each private as it examines them. * Fix race condition in sip_call() if the thread that sent the INVITE is held up long enough for a response to be processed. The p->initid for the INVITE retransmission could be added after it was canceled by the response processing. * Made __sip_destroy() clean up resource pointers after freeing. This is primarily defensive in case someone has a stale private pointer. * Removed redundant memset() in reqprep(). The call to init_req() already does the memset() and is the first reference to req in reqprep(). * Removed useless set of req.method in transmit_invite(). The calls to initreqprep() and reqprep() have to do this because they memset() the req. JIRA ABE-2876 .......... Merged -r373423 from https://origsvn.digium.com/svn/asterisk/be/branches/C.3-bier ........ Merged revisions 373424 from http://svn.asterisk.org/svn/asterisk/branches/1.8 git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@373466 65c4cc65-6c06-0410-ace0-fbb531ad65f3 --- diff --git a/channels/chan_sip.c b/channels/chan_sip.c index d857b5208e..12b747605f 100644 --- a/channels/chan_sip.c +++ b/channels/chan_sip.c @@ -5779,9 +5779,10 @@ static int sip_call(struct ast_channel *ast, char *dest, int timeout) } xmitres = transmit_invite(p, SIP_INVITE, 1, 2, uri); - sip_pvt_unlock(p); - if (xmitres == XMIT_ERROR) + if (xmitres == XMIT_ERROR) { + sip_pvt_unlock(p); return -1; + } p->invitestate = INV_CALLING; /* Initialize auto-congest time */ @@ -5789,6 +5790,7 @@ static int sip_call(struct ast_channel *ast, char *dest, int timeout) dialog_unref(_data, "dialog ptr dec when SCHED_REPLACE del op succeeded"), dialog_unref(p, "dialog ptr dec when SCHED_REPLACE add failed"), dialog_ref(p, "dialog ptr inc when SCHED_REPLACE add succeeded") ); + sip_pvt_unlock(p); } return res; } @@ -5882,6 +5884,7 @@ void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist) if (p->mwi) { p->mwi->call = NULL; + p->mwi = NULL; } if (dumphistory) @@ -5892,29 +5895,37 @@ void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist) ao2_ref(p->options->outboundproxy, -1); } ast_free(p->options); + p->options = NULL; } if (p->notify) { ast_variables_destroy(p->notify->headers); ast_free(p->notify->content); ast_free(p->notify); + p->notify = NULL; } if (p->rtp) { ast_rtp_instance_destroy(p->rtp); + p->rtp = NULL; } if (p->vrtp) { ast_rtp_instance_destroy(p->vrtp); + p->vrtp = NULL; } if (p->trtp) { ast_rtp_instance_destroy(p->trtp); + p->trtp = NULL; } - if (p->udptl) + if (p->udptl) { ast_udptl_destroy(p->udptl); + p->udptl = NULL; + } if (p->refer) { if (p->refer->refer_call) { p->refer->refer_call = dialog_unref(p->refer->refer_call, "unref dialog p->refer->refer_call"); } ast_free(p->refer); + p->refer = NULL; } if (p->route) { free_old_route(p->route); @@ -5967,6 +5978,7 @@ void __sip_destroy(struct sip_pvt *p, int lockowner, int lockdialoglist) ast_string_field_free_memory(p); ast_cc_config_params_destroy(p->cc_params); + p->cc_params = NULL; if (p->epa_entry) { ao2_ref(p->epa_entry, -1); @@ -8197,10 +8209,25 @@ static enum match_req_res match_req_to_dialog(struct sip_pvt *sip_pvt_ptr, struc static void forked_invite_init(struct sip_request *req, const char *new_theirtag, struct sip_pvt *original, struct ast_sockaddr *addr) { struct sip_pvt *p; + const char *callid; + + sip_pvt_lock(original); + callid = ast_strdupa(original->callid); + sip_pvt_unlock(original); - if (!(p = sip_alloc(original->callid, addr, 1, SIP_INVITE, req))) { + if (!(p = sip_alloc(callid, addr, 1, SIP_INVITE, req))) { return; /* alloc error */ } + + /* Lock p and original private structures. */ + sip_pvt_lock(p); + while (sip_pvt_trylock(original)) { + /* Can't use DEADLOCK_AVOIDANCE since p is an ao2 object */ + sip_pvt_unlock(p); + sched_yield(); + sip_pvt_lock(p); + } + p->invitestate = INV_TERMINATED; p->ocseq = original->ocseq; p->branch = original->branch; @@ -8212,6 +8239,9 @@ static void forked_invite_init(struct sip_request *req, const char *new_theirtag ast_string_field_set(p, uri, original->uri); ast_string_field_set(p, our_contact, original->our_contact); ast_string_field_set(p, fullcontact, original->fullcontact); + + sip_pvt_unlock(original); + parse_ok_contact(p, req); build_route(p, req, 1, 0); @@ -8219,6 +8249,7 @@ static void forked_invite_init(struct sip_request *req, const char *new_theirtag transmit_request(p, SIP_BYE, 0, XMIT_RELIABLE, TRUE); pvt_set_needdestroy(p, "forked request"); /* this dialog will terminate once the BYE is responed to or times out. */ + sip_pvt_unlock(p); dialog_unref(p, "setup forked invite termination"); } @@ -8398,7 +8429,9 @@ static struct sip_pvt *find_call(struct sip_request *req, struct ast_sockaddr *a /* Iterate a list of dialogs already matched by Call-id */ while (iterator && (sip_pvt_ptr = ao2_iterator_next(iterator))) { + sip_pvt_lock(sip_pvt_ptr); found = match_req_to_dialog(sip_pvt_ptr, &args); + sip_pvt_unlock(sip_pvt_ptr); switch (found) { case SIP_REQ_MATCH: @@ -8422,6 +8455,7 @@ static struct sip_pvt *find_call(struct sip_request *req, struct ast_sockaddr *a case SIP_REQ_NOT_MATCH: default: dialog_unref(sip_pvt_ptr, "pvt did not match incoming SIP msg, unref from search"); + break; } } if (iterator) { @@ -10685,8 +10719,6 @@ static int reqprep(struct sip_request *req, struct sip_pvt *p, int sipmethod, ui int is_strict = FALSE; /*!< Strict routing flag */ int is_outbound = ast_test_flag(&p->flags[0], SIP_OUTGOING); /* Session direction */ - memset(req, 0, sizeof(struct sip_request)); - snprintf(p->lastmsg, sizeof(p->lastmsg), "Tx: %s", sip_methods[sipmethod].text); if (!seqno) { @@ -12189,19 +12221,21 @@ static void copy_request(struct sip_request *dst, const struct sip_request *src) /* copy the entire request then restore the original data and content * members from the dst request */ - memcpy(dst, src, sizeof(*dst)); + *dst = *src; dst->data = duplicate; dst->content = duplicate_content; /* copy the data into the dst request */ - if (!dst->data && !(dst->data = ast_str_create(ast_str_strlen(src->data) + 1))) + if (!dst->data && !(dst->data = ast_str_create(ast_str_strlen(src->data) + 1))) { return; + } ast_str_copy_string(&dst->data, src->data); /* copy the content into the dst request (if it exists) */ if (src->content) { - if (!dst->content && !(dst->content = ast_str_create(ast_str_strlen(src->content) + 1))) + if (!dst->content && !(dst->content = ast_str_create(ast_str_strlen(src->content) + 1))) { return; + } ast_str_copy_string(&dst->content, src->content); } } @@ -12674,8 +12708,7 @@ static int transmit_invite(struct sip_pvt *p, int sipmethod, int sdp, int init, { struct sip_request req; struct ast_variable *var; - - req.method = sipmethod; + if (init) {/* Bump branch even on initial requests */ p->branch ^= ast_random(); p->invite_branch = p->branch; @@ -18697,13 +18730,18 @@ static int show_chanstats_cb(void *__cur, void *__arg, int flags) char durbuf[10]; int duration; int durh, durm, durs; - struct ast_channel *c = cur->owner; + struct ast_channel *c; struct __show_chan_arg *arg = __arg; int fd = arg->fd; + sip_pvt_lock(cur); + c = cur->owner; - if (cur->subscribed != NONE) /* Subscriptions */ + if (cur->subscribed != NONE) { + /* Subscriptions */ + sip_pvt_unlock(cur); return 0; /* don't care, we scan all channels */ + } if (!cur->rtp) { if (sipdebug) { @@ -18712,10 +18750,12 @@ static int show_chanstats_cb(void *__cur, void *__arg, int flags) invitestate2string[cur->invitestate].desc, "-- No RTP active"); } + sip_pvt_unlock(cur); return 0; /* don't care, we scan all channels */ } if (ast_rtp_instance_get_stats(cur->rtp, &stats, AST_RTP_INSTANCE_STAT_ALL)) { + sip_pvt_unlock(cur); ast_log(LOG_WARNING, "Could not get RTP stats.\n"); return 0; } @@ -18746,6 +18786,7 @@ static int show_chanstats_cb(void *__cur, void *__arg, int flags) stats.txjitter ); arg->numchans++; + sip_pvt_unlock(cur); return 0; /* don't care, we scan all channels */ } @@ -19083,8 +19124,11 @@ static int show_channels_cb(void *__cur, void *__arg, int flags) { struct sip_pvt *cur = __cur; struct __show_chan_arg *arg = __arg; - const struct ast_sockaddr *dst = sip_real_dst(cur); - + const struct ast_sockaddr *dst; + + sip_pvt_lock(cur); + dst = sip_real_dst(cur); + /* XXX indentation preserved to reduce diff. Will be fixed later */ if (cur->subscribed == NONE && !arg->subscriptions) { /* set if SIP transfer in progress */ @@ -19119,6 +19163,7 @@ static int show_channels_cb(void *__cur, void *__arg, int flags) ); arg->numchans++; } + sip_pvt_unlock(cur); return 0; /* don't care, we scan all channels */ }