diff options
| author | Richard Mudgett <rmudgett@digium.com> | 2015-01-20 16:59:30 +0000 |
|---|---|---|
| committer | Richard Mudgett <rmudgett@digium.com> | 2015-01-20 16:59:30 +0000 |
| commit | e4738a59eb7c3b55b096902967cea31e8f842057 (patch) | |
| tree | 931d3d3f9292a7cc38bc5245c16d94e13178e215 /res/snmp | |
| parent | 14b8e03dad718a638f50f9de928b85951cb1e0bc (diff) | |
CHANNEL(peer), chan_iax2, res_fax, SNMP agent: Fix deadlock from reaching across a bridge.
Calling ast_channel_bridge_peer() cannot be done while holding any channel
locks. The reported issue hit the deadlock in chan_iax2, but an audit of
the ast_channel_bridge_peer() calls found three more locations where the
same deadlock can occur.
* Made CHANNEL(peer), res_fax, and the SNMP agent not call
ast_channel_bridge_peer() with any channel locked. For CHANNEL(peer) I
had to rework the logic to not hold the channel lock.
* Made chan_iax2 no longer call ast_channel_bridge_peer(). It was done
for legacy reasons that no longer apply.
* Removed the iax.conf forcejitterbuffer option. It is now always enabled
when the jitterbuffer option is enabled. If you put a jitter buffer on a
channel it will be on the channel.
ASTERISK-24600 #close
Reported by: Jeff Collell
Review: https://reviewboard.asterisk.org/r/4342/
........
Merged revisions 430817 from http://svn.asterisk.org/svn/asterisk/branches/13
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@430819 65c4cc65-6c06-0410-ace0-fbb531ad65f3
Diffstat (limited to 'res/snmp')
| -rw-r--r-- | res/snmp/agent.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/res/snmp/agent.c b/res/snmp/agent.c index abaf37224..9d1528dde 100644 --- a/res/snmp/agent.c +++ b/res/snmp/agent.c @@ -298,12 +298,18 @@ static u_char *ast_var_channels_table(struct variable *vp, oid *name, size_t *le } break; case ASTCHANBRIDGE: - if ((bridge = ast_channel_bridge_peer(chan)) != NULL) { + ast_channel_unlock(chan); + bridge = ast_channel_bridge_peer(chan); + if (bridge) { + ast_channel_lock(bridge); ast_copy_string(string_ret, ast_channel_name(bridge), sizeof(string_ret)); + ast_channel_unlock(bridge); + ast_channel_unref(bridge); + *var_len = strlen(string_ret); ret = (u_char *)string_ret; - ast_channel_unref(bridge); } + ast_channel_lock(chan); break; case ASTCHANMASQ: if (ast_channel_masq(chan) && !ast_strlen_zero(ast_channel_name(ast_channel_masq(chan)))) { |