File 4651-erts-Make-list_to_atom-reject-all-negative... of Package erlang

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File 4651-erts-Make-list_to_atom-reject-all-negative-code-poin.patch of Package erlang

From 8bb74593282447353376b2728989ada311df91a0 Mon Sep 17 00:00:00 2001
From: Sverker Eriksson <sverker@erlang.org>
Date: Mon, 14 Nov 2022 22:19:30 +0100
Subject: [PATCH] erts: Make list_to_atom reject all negative code points
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with a correct badarg exception.

Symptoms: Depending on negative value either

* Accepted as a code point (Value band 16#fff)

1> list_to_atom([-3900]).
  'Ä'

* Rejected but with a broken exception (p->freason not set)

2> catch list_to_atom([-1]).
  {'EXIT',{[],[]}}
---
 erts/emulator/beam/utils.c       | 12 ++++++------
 erts/emulator/test/bif_SUITE.erl |  3 +++
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index d7116bd2c3..4bfc99dd75 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -3648,7 +3648,7 @@ erts_unicode_list_to_buf(Eterm list, byte *buf, Sint len, Sint* written)
 {
     Eterm* listptr;
     Sint sz = 0;
-    Sint val;
+    Uint val;
     int res;
 
     while (1) {
@@ -3671,8 +3671,8 @@ erts_unicode_list_to_buf(Eterm list, byte *buf, Sint len, Sint* written)
 	    res = -1;
             break;
 	}
-	val = signed_val(CAR(listptr));
-	if (0 <= val && val < 0x80) {
+        val = (Uint) signed_val(CAR(listptr));
+	if (val < 0x80) {
 	    buf[sz] = val;
 	    sz++;
 	} else if (val < 0x800) {
@@ -3721,13 +3721,13 @@ erts_unicode_list_to_buf_len(Eterm list)
     listptr = list_val(list);
 
     while (1) {
-	Sint val;
+	Uint val;
 
 	if (is_not_small(CAR(listptr))) {
 	    return -1;
 	}
-	val = signed_val(CAR(listptr));
-	if (0 <= val && val < 0x80) {
+	val = (Uint) signed_val(CAR(listptr));
+	if (val < 0x80) {
 	    sz++;
 	} else if (val < 0x800) {
 	    sz += 2;
diff --git a/erts/emulator/test/bif_SUITE.erl b/erts/emulator/test/bif_SUITE.erl
index 04b7f2de15..aca0174560 100644
--- a/erts/emulator/test/bif_SUITE.erl
+++ b/erts/emulator/test/bif_SUITE.erl
@@ -380,6 +380,9 @@ list_to_utf8_atom(Config) when is_list(Config) ->
     _ = atom_roundtrip([16#1000]),
     _ = atom_roundtrip([16#10FFFF]),
     atom_badarg([16#110000]),
+
+    atom_badarg([-1]),
+    [atom_badarg([(-1 bsl N) + $A]) || N <- lists:seq(8,16)],
     ok.
 
 atom_roundtrip(String) ->
-- 
2.35.3

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File 4651-erts-Make-list_to_atom-reject-all-negative-code-poin.patch of Package erlang

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