Skip to content

Fix segfault (null deref) in named initialisation of nested anonymous union #156

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 1 commit into
base: main
Choose a base branch
from
+30 −7
Open

Fix segfault (null deref) in named initialisation of nested anonymous union #156

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
17 changes: 10 additions & 7 deletions parse.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1003,10 +1003,11 @@ static Member *struct_designator(Token **rest, Token *tok, Type *ty) {

for (Member *mem = ty->members; mem; mem = mem->next) {
// Anonymous struct member
if (mem->ty->kind == TY_STRUCT && !mem->name) {
if (get_struct_member(mem->ty, tok)) {
*rest = start;
return mem;
if (!mem->name) {
if ((mem->ty->kind == TY_STRUCT || mem->ty->kind == TY_UNION)
&& get_struct_member(mem->ty, tok)) {
*rest = start;
return mem;
}
continue;
}
Expand Down Expand Up @@ -2736,11 +2737,13 @@ static Type *union_decl(Token **rest, Token *tok) {

// Find a struct member by name.
static Member *get_struct_member(Type *ty, Token *tok) {
assert(ty->kind == TY_STRUCT || ty->kind == TY_UNION);

for (Member *mem = ty->members; mem; mem = mem->next) {
// Anonymous struct member
if ((mem->ty->kind == TY_STRUCT || mem->ty->kind == TY_UNION) &&
!mem->name) {
if (get_struct_member(mem->ty, tok))
if (!mem->name) {
if ((mem->ty->kind == TY_STRUCT || mem->ty->kind == TY_UNION) &&
get_struct_member(mem->ty, tok))
return mem;
continue;
}
Expand Down
20 changes: 20 additions & 0 deletions test/anon-union-init.c
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,20 @@
#include "test.h"

struct foo {
int simple;
int : 7;
union {
int anon;
union tagged {
float qux;
long baz;
} named;
};
};

struct foo bar = { .simple = 1, .named.qux = 1.0 };

int main() {
printf("OK\n");
return 0;
}