CVE-2024-33600: nscd: Do not send missing not-found response in addgetnetgrentX (bug 31678)

If we failed to add a not-found response to the cache, the dataset
point can be null, resulting in a null pointer dereference.

Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
(cherry picked from commit 7835b00dbc)
This commit is contained in:
Florian Weimer 2024-04-25 15:01:07 +02:00
parent 7a95873543
commit 4370bef52b

View File

@ -147,7 +147,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
/* No such service. */
cacheable = do_notfound (db, fd, req, key, &dataset, &total, &timeout,
&key_copy);
goto writeout;
goto maybe_cache_add;
}
memset (&data, '\0', sizeof (data));
@ -348,7 +348,7 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
{
cacheable = do_notfound (db, fd, req, key, &dataset, &total, &timeout,
&key_copy);
goto writeout;
goto maybe_cache_add;
}
total = buffilled;
@ -410,14 +410,12 @@ addgetnetgrentX (struct database_dyn *db, int fd, request_header *req,
}
if (he == NULL && fd != -1)
{
/* We write the dataset before inserting it to the database
since while inserting this thread might block and so would
unnecessarily let the receiver wait. */
writeout:
/* We write the dataset before inserting it to the database since
while inserting this thread might block and so would
unnecessarily let the receiver wait. */
writeall (fd, &dataset->resp, dataset->head.recsize);
}
maybe_cache_add:
if (cacheable)
{
/* If necessary, we also propagate the data to disk. */