ComputerSurge/bind9
3
0
Fork 0
Code Pull Requests 1 Activity

Fixed a bug that resulted when a callback said to halt a search; the

Browse Source 
level_count was decremented below zero because the found node had not
been put in the level history before the callback broke out of the search.

Added a bunch of INSISTS()s to try to catch something like that in the future.
This commit is contained in:
David Lawrence
1999-04-20 22:01:00 +00:00
parent c91195ca6d
commit acab2c8094
1 changed files with 40 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

64
lib/dns/rbt.c
View File

@@ -15,7 +15,7 @@
* SOFTWARE.
*/
/* $Id: rbt.c,v 1.44 1999/04/20 18:11:07 tale Exp $ */
/* $Id: rbt.c,v 1.45 1999/04/20 22:01:00 tale Exp $ */
/* Principal Authors: DCL */
@@ -802,6 +802,22 @@ dns_rbt_findnode(dns_rbt_t *rbt, dns_name_t *name, dns_name_t *foundname,
if (empty_data_ok || DATA(current) != NULL)
*node = current;
/*
* Point the chain to the next level. This
* needs to be done before 'current' is pointed
* there because the callback in the next
* block of code needs the current 'current',
* but in the event the callback requests that
* the search be stopped then the
* DNS_R_PARTIALMATCH code at the end of this
* function needs the chain pointed to the
* next level.
*/
ADD_ANCESTOR(chain, NULL);
ADD_LEVEL(chain, current);
chain->level_matches++;
/*
* The caller may want to interrupt the
* downward search when certain special nodes
@@ -810,15 +826,13 @@ dns_rbt_findnode(dns_rbt_t *rbt, dns_name_t *name, dns_name_t *foundname,
* caller wants to do.
*/
if (callback != NULL && CALLBACK(current)) {
chain->end = current;
result = chain_name(chain,
callback_name,
ISC_TRUE);
ISC_FALSE);
if (result != DNS_R_SUCCESS) {
dns_rbtnodechain_reset(chain);
return (result);
}
chain->end = NULL;
result = (callback)(current,
callback_name,
@@ -835,12 +849,8 @@ dns_rbt_findnode(dns_rbt_t *rbt, dns_name_t *name, dns_name_t *foundname,
}
/*
* Search in the next tree level.
* Finally, head to the next tree level.
*/
ADD_ANCESTOR(chain, NULL);
ADD_LEVEL(chain, current);
chain->level_matches++;
current = DOWN(current);
} else {
@@ -888,8 +898,10 @@ dns_rbt_findnode(dns_rbt_t *rbt, dns_name_t *name, dns_name_t *foundname,
unsigned int saved_count = chain->level_count;
while (chain->levels[chain->level_count - 1] !=
*node)
*node) {
INSIST(chain->level_count > 1);
chain->level_count--;
}
result = chain_name(chain, foundname,
ISC_FALSE);
@@ -915,6 +927,7 @@ dns_rbt_findnode(dns_rbt_t *rbt, dns_name_t *name, dns_name_t *foundname,
* history.
*/
INSIST(chain->ancestor_count > 0);
current = chain->ancestors[--chain->ancestor_count];
if (current == NULL) {
@@ -926,6 +939,8 @@ dns_rbt_findnode(dns_rbt_t *rbt, dns_name_t *name, dns_name_t *foundname,
* order against, the terminal name is the
* predecessor.
*/
INSIST(chain->level_count > 0 &&
chain->level_matches > 0);
chain->end =
chain->levels[--chain->level_count];
chain->level_matches--;
@@ -1115,6 +1130,7 @@ zapnode_and_fixlevels(dns_rbt_t *rbt, dns_rbtnode_t *node,
* item. That item's name can be joined with the name
* on this level.
*/
INSIST(chain->ancestor_count > 0);
rootp = chain->level_count > 0 ?
&DOWN(chain->levels[chain->level_count - 1]) :
&rbt->root;
@@ -1852,16 +1868,14 @@ dns_rbtnodechain_current(dns_rbtnodechain_t *chain, dns_name_t *name,
REQUIRE(VALID_CHAIN(chain));
if (node != NULL)
*node = chain->end;
if (chain->end == NULL)
return (DNS_R_NOTFOUND);
if (name != NULL) {
if (chain->end != NULL)
NODENAME(chain->end, name);
else
/*
* Any offsets are zapped by this call, but they
* would have been redirected anyway if there
* was a chain_end.
*/
dns_name_init(name, NULL);
NODENAME(chain->end, name);
if (chain->level_count == 0) {
/*
@@ -1889,11 +1903,7 @@ dns_rbtnodechain_current(dns_rbtnodechain_t *chain, dns_name_t *name,
}
if (node != NULL)
*node = chain->end;
return (result);
}
dns_result_t
@@ -1923,6 +1933,7 @@ dns_rbtnodechain_prev(dns_rbtnodechain_t *chain, dns_name_t *name,
} else {
while (chain->ancestors[chain->ancestor_count - 1] != NULL) {
INSIST(chain->ancestor_count > 1);
previous = current;
current = chain->ancestors[--chain->ancestor_count];
@@ -1970,6 +1981,8 @@ dns_rbtnodechain_prev(dns_rbtnodechain_t *chain, dns_name_t *name,
* Got to the root of this level without having traversed
* any right links. Ascend the tree one level.
*/
INSIST(chain->level_count > 0 &&
chain->ancestor_count > 0);
predecessor = chain->levels[--chain->level_count];
chain->ancestor_count--;
@@ -2052,6 +2065,7 @@ dns_rbtnodechain_next(dns_rbtnodechain_t *chain, dns_name_t *name,
do {
while (chain->ancestors[chain->ancestor_count - 1] !=
NULL) {
INSIST(chain->ancestor_count > 1);
previous = current;
current =
chain->ancestors[--chain->ancestor_count];
@@ -2067,8 +2081,10 @@ dns_rbtnodechain_next(dns_rbtnodechain_t *chain, dns_name_t *name,
* Reached the root without having traversed
* any left pointers, so this level is done.
*/
chain->ancestor_count--;
INSIST(chain->level_count > 0 &&
chain->ancestor_count > 0);
current = chain->levels[--chain->level_count];
chain->ancestor_count--;
new_origin = ISC_TRUE;
if (RIGHT(current) != NULL)