From: Robin Sonefors
We didn't initialize parent_map, meaning that it could have any value,
even though it appears it is not infrequently NULL, at least at first.
We then pointed it to a bitmap object iff
xodtemplate_servicedependency_list wasn't NULL, and finally freed it
unconditionally.
Thus, unless parent_map pointed at NULL or we have servicedependencies,
we'd get a crash.
Now, if we first add at least one servicedependency, run nagios, remove
all of them, and reload nagios, parent_map would still keep its old
value around, we wouldn't reallocate it, but we'd still free it, leading
to a crash.
This is prevented in the following ways:
* First, make sure all bitmaps are NULL-initialized, clearly and
obviously.
* Second, only free parent_map if we did set it.
* Third, set parent_map to NULL after we destroy() it - dangling
pointers are evil.
Signed-off-by: Robin Sonefors
---
xdata/xodtemplate.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/xdata/xodtemplate.c b/xdata/xodtemplate.c
index 5b3a099..34da566 100644
--- a/xdata/xodtemplate.c
+++ b/xdata/xodtemplate.c
@@ -118,9 +118,9 @@ static struct object_count xodcount;
#ifndef NSCGI
/* reusable bitmaps for expanding objects */
-static bitmap *host_map, *contact_map;
+static bitmap *host_map = NULL, *contact_map = NULL;
#endif
-static bitmap *service_map, *parent_map;
+static bitmap *service_map = NULL, *parent_map = NULL;
/*
@@ -6901,18 +6901,19 @@ int xodtemplate_register_objects(void) {
logit(NSLOG_CONFIG_ERROR, TRUE, "Error: Failed to create parent bitmap for service dependencies\n");
return ERROR;
}
- }
- for(sd = xodtemplate_servicedependency_list; sd; sd = next_sd) {
- next_sd = sd->next;
+ for(sd = xodtemplate_servicedependency_list; sd; sd = next_sd) {
+ next_sd = sd->next;
#ifdef NSCGI
- if(xodtemplate_register_servicedependency(sd) == ERROR)
- return ERROR;
+ if(xodtemplate_register_servicedependency(sd) == ERROR)
+ return ERROR;
#else
- if(xodtemplate_register_and_destroy_servicedependency(sd) == ERROR)
- return ERROR;
+ if(xodtemplate_register_and_destroy_servicedependency(sd) == ERROR)
+ return ERROR;
#endif
+ }
+ bitmap_destroy(parent_map);
+ parent_map = NULL;
}
- bitmap_destroy(parent_map);
timing_point("%u unique / %u total servicedependencies registered\n",
num_objects.servicedependencies, xodcount.servicedependencies);
--
1.7.11.7
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Original poster: [email protected]