OSS-Fuzz found a Null-dereference in __cil_insert_name when trying to compile the following policy: (macro MACRO () (classmap CLASS (PERM)) (type TYPE) (typetransition TYPE TYPE CLASS "name" TYPE) ) (call MACRO) When using a macro with no argument, macro->params is NULL and cil_list_for_each(item, macro->params) dereferenced a NULL pointer. Fix this by checking that macro->params is not NULL before using it. Fixes: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=28565 Signed-off-by: Nicolas Iooss <nicolas.iooss@xxxxxxx> --- libsepol/cil/src/cil_resolve_ast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libsepol/cil/src/cil_resolve_ast.c b/libsepol/cil/src/cil_resolve_ast.c index 2ea106d63505..63beed9230b9 100644 --- a/libsepol/cil/src/cil_resolve_ast.c +++ b/libsepol/cil/src/cil_resolve_ast.c @@ -82,7 +82,7 @@ static struct cil_name * __cil_insert_name(struct cil_db *db, hashtab_key_t key, } else if (parent->flavor == CIL_MACRO) { macro = parent->data; } - if (macro != NULL) { + if (macro != NULL && macro->params != NULL) { struct cil_list_item *item; cil_list_for_each(item, macro->params) { if (((struct cil_param*)item->data)->str == key) { -- 2.30.2