File 0280-erts-Fix-spawn_request-trace-bug.patch of Package erlang

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File 0280-erts-Fix-spawn_request-trace-bug.patch of Package erlang (Revision fe162c0c563b11430d77cc39dc990d22)

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From 6bde6ed499f34ad25934b7e1a0d763c4ce1ee725 Mon Sep 17 00:00:00 2001
From: Lukas Larsson <lukas@erlang.org>
Date: Mon, 17 Jan 2022 14:34:27 +0100
Subject: [PATCH] erts: Fix spawn_request trace bug

Since the args of spawn_request may end up in a trace
we need to allocate them on the heap of the spawning process.
We cannot use a temporary heap for this as
allocates on normal heap and this will lead to stray pointers
on the heap during gc. Stray pointers are not always a problem
as any dead data is ignored, but if the pointers and up in a
heap fragments they are not ignored...
---
 erts/emulator/beam/bif.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c
index eefb722c56..bdf1f71509 100644
--- a/erts/emulator/beam/bif.c
+++ b/erts/emulator/beam/bif.c
@@ -856,8 +856,7 @@ BIF_RETTYPE spawn_opt_4(BIF_ALIST_4)
 BIF_RETTYPE erts_internal_spawn_request_4(BIF_ALIST_4)
 {
     ErlSpawnOpts so;
-    Eterm tmp_heap_mfna[4];
-    Eterm tmp_heap_alist[4 + 2];
+    Eterm *hp;
     Sint arity;
     int opts_error;
     Eterm tag, tmp, error;
@@ -884,16 +883,18 @@ BIF_RETTYPE erts_internal_spawn_request_4(BIF_ALIST_4)
         goto badopt;
     }
 
+    hp = HAlloc(BIF_P, 4 + 4 + 2);
+
     /* Make argument list for erts_internal:spawn_init/1 */
-    tmp = TUPLE3(&tmp_heap_alist[0], BIF_ARG_1, BIF_ARG_2, BIF_ARG_3);
-    tmp = CONS(&tmp_heap_alist[4], tmp, NIL);
+    tmp = TUPLE3(hp, BIF_ARG_1, BIF_ARG_2, BIF_ARG_3); hp += 4;
+    tmp = CONS(hp, tmp, NIL); hp += 2;
 
-    so.mfa = TUPLE3(&tmp_heap_mfna[0], BIF_ARG_1, BIF_ARG_2, make_small(arity));    
+    so.mfa = TUPLE3(hp, BIF_ARG_1, BIF_ARG_2, make_small(arity)); hp += 4;
     so.flags |= SPO_ASYNC;
     so.mref = THE_NON_VALUE;
     so.tag = tag;
     so.opts = BIF_ARG_4;
-    
+
     /*
      * Spawn the process.
      */
-- 
2.31.1

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File 0280-erts-Fix-spawn_request-trace-bug.patch of Package erlang (Revision fe162c0c563b11430d77cc39dc990d22)

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