Several places in the code called find_callno() (which releases the lock on the pvt...

Added find_callno_locked() function to return the callno withtout unlocking for instances that it is needed.

(issue #12400)
Reported by: ztel

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@114083 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_iax2.c b/channels/chan_iax2.c
index a204c7f7ac0f71aafca0178d836cc5cf87cfded7..8c28003a0a6be6eb4794edffc52453d548442448 100644 (file)
--- a/channels/chan_iax2.c
+++ b/channels/chan_iax2.c
@@ -1336,7 +1336,7 @@ static int make_trunk(unsigned short callno, int locked)
 /*!
  * \note Calling this function while holding another pvt lock can cause a deadlock.
  */
-static int find_callno(unsigned short callno, unsigned short dcallno, struct sockaddr_in *sin, int new, int sockfd)
+static int __find_callno(unsigned short callno, unsigned short dcallno, struct sockaddr_in *sin, int new, int sockfd, int return_locked)
 {
        int res = 0;
        int x;
@@ -1413,12 +1413,23 @@ static int find_callno(unsigned short callno, unsigned short dcallno, struct soc
                        ast_mutex_unlock(&iaxsl[x]);
                        return 0;
                }
-               ast_mutex_unlock(&iaxsl[x]);
+               if (!return_locked)
+                       ast_mutex_unlock(&iaxsl[x]);
                res = x;
        }
        return res;
 }
 
+static int find_callno(unsigned short callno, unsigned short dcallno, struct sockaddr_in *sin, int new, int sockfd) {
+
+       return __find_callno(callno, dcallno, sin, new, sockfd, 0);
+}
+
+static int find_callno_locked(unsigned short callno, unsigned short dcallno, struct sockaddr_in *sin, int new, int sockfd) {
+
+       return __find_callno(callno, dcallno, sin, new, sockfd, 1);
+}
+
 static void iax2_frame_free(struct iax_frame *fr)
 {
        AST_SCHED_DEL(sched, fr->retrans);
@@ -3592,6 +3603,14 @@ static struct ast_channel *ast_iax2_new(int callno, int state, int capability)
        ast_mutex_unlock(&iaxsl[callno]);
        tmp = ast_channel_alloc(1, state, i->cid_num, i->cid_name, i->accountcode, i->exten, i->context, i->amaflags, "IAX2/%s-%d", i->host, i->callno);
        ast_mutex_lock(&iaxsl[callno]);
+       if (!iaxs[callno]) {
+               if (tmp) {
+                       ast_channel_free(tmp);
+               }
+               ast_mutex_unlock(&iaxsl[callno]);
+               return NULL;
+       }
+
        if (!tmp)
                return NULL;
        tmp->tech = &iax2_tech;
@@ -6906,9 +6925,8 @@ static int socket_process(struct iax2_thread *thread)
                                /* Stop if we don't have enough data */
                                if (len > res)
                                        break;
-                               fr->callno = find_callno(callno & ~IAX_FLAG_FULL, 0, &sin, NEW_PREVENT, fd);
+                               fr->callno = find_callno_locked(callno & ~IAX_FLAG_FULL, 0, &sin, NEW_PREVENT, fd);
                                if (fr->callno) {
-                                       ast_mutex_lock(&iaxsl[fr->callno]);
                                        /* If it's a valid call, deliver the contents.  If not, we
                                           drop it, since we don't have a scallno to use for an INVAL */
                                        /* Process as a mini frame */
@@ -7159,7 +7177,9 @@ static int socket_process(struct iax2_thread *thread)
                                        if (call_to_destroy) {
                                                if (iaxdebug && option_debug)
                                                        ast_log(LOG_DEBUG, "Really destroying %d, having been acked on final message\n", call_to_destroy);
+                                               ast_mutex_lock(&iaxsl[call_to_destroy]);
                                                iax2_destroy(call_to_destroy);
+                                               ast_mutex_unlock(&iaxsl[call_to_destroy]);
                                        }
                                }
                                /* Note how much we've received acknowledgement for */
@@ -8486,13 +8506,14 @@ static int iax2_do_register(struct iax2_registry *reg)
        if (!reg->callno) {
                if (option_debug)
                        ast_log(LOG_DEBUG, "Allocate call number\n");
-               reg->callno = find_callno(0, 0, &reg->addr, NEW_FORCE, defaultsockfd);
+               reg->callno = find_callno_locked(0, 0, &reg->addr, NEW_FORCE, defaultsockfd);
                if (reg->callno < 1) {
                        ast_log(LOG_WARNING, "Unable to create call for registration\n");
                        return -1;
                } else if (option_debug)
                        ast_log(LOG_DEBUG, "Registration created on call %d\n", reg->callno);
                iaxs[reg->callno]->reg = reg;
+               ast_mutex_unlock(&iaxsl[reg->callno]);
        }
        /* Schedule the next registration attempt */
        AST_SCHED_DEL(sched, reg->expire);
@@ -8546,11 +8567,10 @@ static int iax2_provision(struct sockaddr_in *end, int sockfd, char *dest, const
        memset(&ied, 0, sizeof(ied));
        iax_ie_append_raw(&ied, IAX_IE_PROVISIONING, provdata.buf, provdata.pos);
 
-       callno = find_callno(0, 0, &sin, NEW_FORCE, cai.sockfd);
+       callno = find_callno_locked(0, 0, &sin, NEW_FORCE, cai.sockfd);
        if (!callno)
                return -1;
 
-       ast_mutex_lock(&iaxsl[callno]);
        if (iaxs[callno]) {
                /* Schedule autodestruct in case they don't ever give us anything back */
                AST_SCHED_DEL(sched, iaxs[callno]->autoid);
@@ -8768,15 +8788,13 @@ static struct ast_channel *iax2_request(const char *type, int format, void *data
        if (pds.port)
                sin.sin_port = htons(atoi(pds.port));
 
-       callno = find_callno(0, 0, &sin, NEW_FORCE, cai.sockfd);
+       callno = find_callno_locked(0, 0, &sin, NEW_FORCE, cai.sockfd);
        if (callno < 1) {
                ast_log(LOG_WARNING, "Unable to create call\n");
                *cause = AST_CAUSE_CONGESTION;
                return NULL;
        }
 
-       ast_mutex_lock(&iaxsl[callno]);
-
        /* If this is a trunk, update it now */
        ast_copy_flags(iaxs[callno], &cai, IAX_TRUNK | IAX_SENDANI | IAX_NOTRANSFER | IAX_TRANSFERMEDIA | IAX_USEJITTERBUF | IAX_FORCEJITTERBUF);       
        if (ast_test_flag(&cai, IAX_TRUNK)) {
@@ -10084,13 +10102,12 @@ static int cache_get_callno_locked(const char *data)
                ast_log(LOG_DEBUG, "peer: %s, username: %s, password: %s, context: %s\n",
                        pds.peer, pds.username, pds.password, pds.context);
 
-       callno = find_callno(0, 0, &sin, NEW_FORCE, cai.sockfd);
+       callno = find_callno_locked(0, 0, &sin, NEW_FORCE, cai.sockfd);
        if (callno < 1) {
                ast_log(LOG_WARNING, "Unable to create call\n");
                return -1;
        }
 
-       ast_mutex_lock(&iaxsl[callno]);
        ast_string_field_set(iaxs[callno], dproot, data);
        iaxs[callno]->capability = IAX_CAPABILITY_FULLBANDWIDTH;