0002-Revert-Fix-jump-buffer-leak-in-setjmp-handler-in-WAS.patch

From 72a19c53d2ef1d3d452ad23fe3efc9e02de3a45c Mon Sep 17 00:00:00 2001
From: Yuta Saito <kateinoigakukun@gmail.com>
Date: Tue, 1 Apr 2025 05:48:27 +0000
Subject: [PATCH 2/3] Revert "Fix jump buffer leak in setjmp handler in WASI
 builds"

This reverts commit 3a730be8b464454878a42132f6fecb98ab4c1b5b.
---
 cont.c        |  1 -
 eval_intern.h |  4 +--
 vm_core.h     | 77 +++++++++++++++++----------------------------------
 3 files changed, 27 insertions(+), 55 deletions(-)

diff --git a/cont.c b/cont.c
index ae68da4e83..072ae4562f 100644
--- a/cont.c
+++ b/cont.c
@@ -1369,7 +1369,6 @@ cont_init(rb_context_t *cont, rb_thread_t *th)
     /* save thread context */
     cont_save_thread(cont, th);
     cont->saved_ec.thread_ptr = th;
-    cont->saved_ec.tag = NULL;
     cont->saved_ec.local_storage = NULL;
     cont->saved_ec.local_storage_recursive_hash = Qnil;
     cont->saved_ec.local_storage_recursive_hash_for_trace = Qnil;
diff --git a/eval_intern.h b/eval_intern.h
index 49229fa82d..ab0577e8ed 100644
--- a/eval_intern.h
+++ b/eval_intern.h
@@ -102,11 +102,11 @@ extern int select_large_fdset(int, fd_set *, fd_set *, fd_set *, struct timeval
   _tag.tag = Qundef; \
   _tag.prev = _ec->tag; \
   _tag.lock_rec = rb_ec_vm_lock_rec(_ec); \
-  rb_vm_tag_jmpbuf_init(&_tag);
+  rb_vm_tag_jmpbuf_init(&_tag.buf); \
 
 #define EC_POP_TAG() \
   _ec->tag = _tag.prev; \
-  rb_vm_tag_jmpbuf_deinit(&_tag); \
+  rb_vm_tag_jmpbuf_deinit(&_tag.buf); \
 } while (0)
 
 #define EC_TMPPOP_TAG() \
diff --git a/vm_core.h b/vm_core.h
index 28d742feed..d9159f5ccf 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -946,79 +946,52 @@ typedef void *rb_jmpbuf_t[5];
   Therefore, we allocates the buffer on the heap on such
   environments.
 */
-typedef struct _rb_vm_tag_jmpbuf {
-    struct _rb_vm_tag_jmpbuf *next;
-    rb_jmpbuf_t buf;
-} *rb_vm_tag_jmpbuf_t;
+typedef rb_jmpbuf_t *rb_vm_tag_jmpbuf_t;
 
-#define RB_VM_TAG_JMPBUF_GET(jmpbuf) ((jmpbuf)->buf)
-#else
-typedef rb_jmpbuf_t rb_vm_tag_jmpbuf_t;
-
-#define RB_VM_TAG_JMPBUF_GET(jmpbuf) (jmpbuf)
-#endif
-
-/*
-  the members which are written in EC_PUSH_TAG() should be placed at
-  the beginning and the end, so that entire region is accessible.
-*/
-struct rb_vm_tag {
-    VALUE tag;
-    VALUE retval;
-    rb_vm_tag_jmpbuf_t buf;
-    struct rb_vm_tag *prev;
-    enum ruby_tag_type state;
-    unsigned int lock_rec;
-};
-
-#if defined(__wasm__) && !defined(__EMSCRIPTEN__)
-static inline void
-_rb_vm_tag_jmpbuf_deinit_internal(rb_vm_tag_jmpbuf_t jmpbuf)
-{
-    rb_vm_tag_jmpbuf_t buf = jmpbuf;
-    while (buf != NULL) {
-        rb_vm_tag_jmpbuf_t next = buf->next;
-        ruby_xfree(buf);
-        buf = next;
-    }
-}
+#define RB_VM_TAG_JMPBUF_GET(buf) (*buf)
 
 static inline void
-rb_vm_tag_jmpbuf_init(struct rb_vm_tag *tag)
+rb_vm_tag_jmpbuf_init(rb_vm_tag_jmpbuf_t *jmpbuf)
 {
-    if (tag->prev != NULL && tag->prev->buf->next != NULL) {
-        _rb_vm_tag_jmpbuf_deinit_internal(tag->prev->buf->next);
-        tag->prev->buf->next = NULL;
-    }
-    tag->buf = ruby_xmalloc(sizeof *tag->buf);
-    tag->buf->next = NULL;
-    if (tag->prev != NULL) {
-        tag->prev->buf->next = tag->buf;
-    }
+    *jmpbuf = ruby_xmalloc(sizeof(rb_jmpbuf_t));
 }
 
 static inline void
-rb_vm_tag_jmpbuf_deinit(struct rb_vm_tag *tag)
+rb_vm_tag_jmpbuf_deinit(const rb_vm_tag_jmpbuf_t *jmpbuf)
 {
-    if (tag->prev != NULL) {
-        tag->prev->buf->next = NULL;
-    }
-    _rb_vm_tag_jmpbuf_deinit_internal(tag->buf);
+    ruby_xfree(*jmpbuf);
 }
 #else
+typedef rb_jmpbuf_t rb_vm_tag_jmpbuf_t;
+
+#define RB_VM_TAG_JMPBUF_GET(buf) (buf)
+
 static inline void
-rb_vm_tag_jmpbuf_init(struct rb_vm_tag *tag)
+rb_vm_tag_jmpbuf_init(rb_vm_tag_jmpbuf_t *jmpbuf)
 {
     // no-op
 }
 
 static inline void
-rb_vm_tag_jmpbuf_deinit(struct rb_vm_tag *tag)
+rb_vm_tag_jmpbuf_deinit(const rb_vm_tag_jmpbuf_t *jmpbuf)
 {
     // no-op
 }
 #endif
 
+/*
+  the members which are written in EC_PUSH_TAG() should be placed at
+  the beginning and the end, so that entire region is accessible.
+*/
+struct rb_vm_tag {
+    VALUE tag;
+    VALUE retval;
+    rb_vm_tag_jmpbuf_t buf;
+    struct rb_vm_tag *prev;
+    enum ruby_tag_type state;
+    unsigned int lock_rec;
+};
+
 STATIC_ASSERT(rb_vm_tag_buf_offset, offsetof(struct rb_vm_tag, buf) > 0);
 STATIC_ASSERT(rb_vm_tag_buf_end,
               offsetof(struct rb_vm_tag, buf) + sizeof(rb_vm_tag_jmpbuf_t) <
-- 
2.48.1