diff options
| author | Gary Lockyer <gary@catalyst.net.nz> | 2020-05-13 10:56:56 +1200 |
|---|---|---|
| committer | Karolin Seeger <kseeger@samba.org> | 2020-06-25 13:04:45 +0200 |
| commit | d6848d2f3f281956d8401f11ed1a6b609f802e21 (patch) | |
| tree | f0522c923f3020dfafe433260cacfb4400dc6b81 | |
| parent | d400d7d8ac66ab889c3f1a6572fec64f20f0861e (diff) | |
| download | samba-d6848d2f3f281956d8401f11ed1a6b609f802e21.tar.gz | |
CVE-2020-10730: lib ldb: Check if ldb_lock_backend_callback called twice
Prevent use after free issues if ldb_lock_backend_callback is called
twice, usually due to ldb_module_done being called twice. This can happen if a
module ignores the return value from function a function that calls
ldb_module_done as part of it's error handling.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=14364
Signed-off-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
| -rw-r--r-- | lib/ldb/common/ldb.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/lib/ldb/common/ldb.c b/lib/ldb/common/ldb.c index 44a487ba987..090d41dde69 100644 --- a/lib/ldb/common/ldb.c +++ b/lib/ldb/common/ldb.c @@ -1009,6 +1009,13 @@ static int ldb_lock_backend_callback(struct ldb_request *req, struct ldb_db_lock_context *lock_context; int ret; + if (req->context == NULL) { + /* + * The usual way to get here is to ignore the return codes + * and continuing processing after an error. + */ + abort(); + } lock_context = talloc_get_type(req->context, struct ldb_db_lock_context); @@ -1023,7 +1030,7 @@ static int ldb_lock_backend_callback(struct ldb_request *req, * If this is a LDB_REPLY_DONE or an error, unlock the * DB by calling the destructor on this context */ - talloc_free(lock_context); + TALLOC_FREE(req->context); return ret; } |