From 7bce362fa7a8eaea13828f9091a1c3298f3e7400 Mon Sep 17 00:00:00 2001 From: Mark Michelson Date: Fri, 11 Apr 2008 15:44:28 +0000 Subject: [PATCH] Fix a race condition that may happen between a sip hangup and a "core show channel" command. This patch adds locking to prevent the resulting crash. (closes issue #12155) Reported by: tsearle Patches: show_channels_crash2.patch uploaded by tsearle (license 373) Tested by: tsearle git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@114063 65c4cc65-6c06-0410-ace0-fbb531ad65f3 --- res/res_features.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/res/res_features.c b/res/res_features.c index e21269640c..7eb1b4c4c9 100644 --- a/res/res_features.c +++ b/res/res_features.c @@ -1585,22 +1585,35 @@ int ast_bridge_call(struct ast_channel *chan,struct ast_channel *peer,struct ast bridge_cdr = ast_cdr_alloc(); if (bridge_cdr) { if (chan->cdr && peer->cdr) { /* both of them? merge */ + ast_channel_lock(chan); /* lock the channel before modifing cdrs */ ast_cdr_init(bridge_cdr,chan); /* seems more logicaller to use the destination as a base, but, really, it's random */ ast_cdr_start(bridge_cdr); /* now is the time to start */ /* absorb the channel cdr */ ast_cdr_merge(bridge_cdr, chan->cdr); - if (!ast_test_flag(chan->cdr, AST_CDR_FLAG_LOCKED)) + if (!ast_test_flag(chan->cdr, AST_CDR_FLAG_LOCKED)) ast_cdr_discard(chan->cdr); /* if locked cdrs are in chan, they are taken over in the merge */ + + chan->cdr = NULL; /* remove pointer to freed memory before releasing the lock */ + + ast_channel_unlock(chan); /* absorb the peer cdr */ + ast_channel_lock(peer); ast_cdr_merge(bridge_cdr, peer->cdr); if (!ast_test_flag(peer->cdr, AST_CDR_FLAG_LOCKED)) ast_cdr_discard(peer->cdr); /* if locked cdrs are in peer, they are taken over in the merge */ peer->cdr = NULL; + ast_channel_unlock(peer); + + ast_channel_lock(chan); chan->cdr = bridge_cdr; /* make this available to the rest of the world via the chan while the call is in progress */ + ast_channel_unlock(chan); + } else if (chan->cdr) { + + ast_channel_lock(chan); /* Lock before modifying CDR */ /* take the cdr from the channel - literally */ ast_cdr_init(bridge_cdr,chan); /* absorb this data */ @@ -1608,7 +1621,9 @@ int ast_bridge_call(struct ast_channel *chan,struct ast_channel *peer,struct ast if (!ast_test_flag(chan->cdr, AST_CDR_FLAG_LOCKED)) ast_cdr_discard(chan->cdr); /* if locked cdrs are in chan, they are taken over in the merge */ chan->cdr = bridge_cdr; /* make this available to the rest of the world via the chan while the call is in progress */ + ast_channel_unlock(chan); } else if (peer->cdr) { + ast_channel_lock(peer); /* Lock before modifying CDR */ /* take the cdr from the peer - literally */ ast_cdr_init(bridge_cdr,peer); /* absorb this data */ @@ -1617,10 +1632,13 @@ int ast_bridge_call(struct ast_channel *chan,struct ast_channel *peer,struct ast ast_cdr_discard(peer->cdr); /* if locked cdrs are in chan, they are taken over in the merge */ peer->cdr = NULL; peer->cdr = bridge_cdr; /* make this available to the rest of the world via the chan while the call is in progress */ + ast_channel_unlock(peer); } else { + ast_channel_lock(chan); /* Lock before modifying CDR */ /* make up a new cdr */ ast_cdr_init(bridge_cdr,chan); /* eh, just pick one of them */ chan->cdr = bridge_cdr; /* */ + ast_channel_unlock(chan); } if (ast_strlen_zero(bridge_cdr->dstchannel)) { if (strcmp(bridge_cdr->channel, peer->name) != 0)