ungoogled-chromium-xdg-aur/sandbox-build-if-glibc-2.34-dynamic-stack-size-is-en.patch

From 28ac6a15411d01301e171b8a8b0019abd57589b9 Mon Sep 17 00:00:00 2001
From: Stephan Hartmann <stha09@googlemail.com>
Date: Mon, 7 Feb 2022 20:09:57 +0000
Subject: [PATCH] sandbox: build if glibc 2.34+ dynamic stack size is enabled
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Compilation of sandbox fails when using dynamic stack size in glibc
2.34 or newer. This is because the value is not a literal anymore but
obtained through sysconf.

To avoid this, use memset to put zeros in the buffer.

Change-Id: Ia479e0f799b77a10a00197aaaa0500e62546f458
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3436947
Reviewed-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Commit-Queue: José Dapena Paz <jdapena@igalia.com>
Cr-Commit-Position: refs/heads/main@{#967943}
---
 sandbox/linux/services/credentials.cc | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/sandbox/linux/services/credentials.cc b/sandbox/linux/services/credentials.cc
index ca6b5954798..c933eafd163 100644
--- a/sandbox/linux/services/credentials.cc
+++ b/sandbox/linux/services/credentials.cc
@@ -100,7 +100,10 @@ bool ChrootToSafeEmptyDir() {
   // TODO(crbug.com/1247458) Broken in MSan builds after LLVM f1bb30a4956f.
   clone_flags |= CLONE_VM | CLONE_VFORK | CLONE_SETTLS;
 
-  char tls_buf[PTHREAD_STACK_MIN] = {0};
+  // PTHREAD_STACK_MIN can be dynamic in glibc2.34+, so it is not possible to
+  // zeroify tls_buf assigning { 0 }
+  char tls_buf[PTHREAD_STACK_MIN];
+  memset(tls_buf, 0, PTHREAD_STACK_MIN);
   tls = tls_buf;
 #endif