On Sun, Mar 14, 2021 at 4:22 PM Nicolas Iooss <nicolas.iooss@xxxxxxx> wrote: > > 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> Acked-by: James Carter <jwcart2@xxxxxxxxx> > --- > 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 >
