diff options
author | Richard Mudgett <rmudgett@digium.com> | 2012-12-17 23:10:42 +0000 |
---|---|---|
committer | Richard Mudgett <rmudgett@digium.com> | 2012-12-17 23:10:42 +0000 |
commit | 5e2c52a546f6e38939abc40e88058fc253467d79 (patch) | |
tree | f542a76a366f815365fe29e5519c011337a9bd43 /main/loader.c | |
parent | 23b94b92117ae965c0e9a11cd3804486cb54f793 (diff) |
Fix potential double free when unloading a module.
........
Merged revisions 378092 from http://svn.asterisk.org/svn/asterisk/branches/1.8
........
Merged revisions 378093 from http://svn.asterisk.org/svn/asterisk/branches/10
........
Merged revisions 378094 from http://svn.asterisk.org/svn/asterisk/branches/11
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@378095 65c4cc65-6c06-0410-ace0-fbb531ad65f3
Diffstat (limited to 'main/loader.c')
-rw-r--r-- | main/loader.c | 28 |
1 files changed, 24 insertions, 4 deletions
diff --git a/main/loader.c b/main/loader.c index 2af9d2006..7ad515f8a 100644 --- a/main/loader.c +++ b/main/loader.c @@ -237,9 +237,18 @@ void __ast_module_user_remove(struct ast_module *mod, struct ast_module_user *u) if (!u) { return; } + AST_LIST_LOCK(&mod->users); - AST_LIST_REMOVE(&mod->users, u, entry); + u = AST_LIST_REMOVE(&mod->users, u, entry); AST_LIST_UNLOCK(&mod->users); + if (!u) { + /* + * Was not in the list. Either a bad pointer or + * __ast_module_user_hangup_all() has been called. + */ + return; + } + ast_atomic_fetchadd_int(&mod->usecount, -1); ast_free(u); @@ -559,15 +568,26 @@ int ast_unload_resource(const char *resource_name, enum ast_module_unload_mode f } if (!error) { + /* Request any channels attached to the module to hangup. */ __ast_module_user_hangup_all(mod); - res = mod->info->unload(); + res = mod->info->unload(); if (res) { ast_log(LOG_WARNING, "Firm unload failed for %s\n", resource_name); - if (force <= AST_FORCE_FIRM) + if (force <= AST_FORCE_FIRM) { error = 1; - else + } else { ast_log(LOG_WARNING, "** Dangerous **: Unloading resource anyway, at user request\n"); + } + } + + if (!error) { + /* + * Request hangup on any channels that managed to get attached + * while we called the module unload function. + */ + __ast_module_user_hangup_all(mod); + sched_yield(); } } |