linux-kernel - Re: [PATCH v5 01/16] x86/stackprotector: Work around strict Clang TLS symbol requirements

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241206115154.GA32491@redhat.com>
Date: Fri, 6 Dec 2024 12:51:54 +0100
From: Oleg Nesterov <oleg@...hat.com>
To: Brian Gerst <brgerst@...il.com>
Cc: linux-kernel@...r.kernel.org, x86@...nel.org,
	Ingo Molnar <mingo@...nel.org>, "H . Peter Anvin" <hpa@...or.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Borislav Petkov <bp@...en8.de>, Ard Biesheuvel <ardb@...nel.org>,
	Uros Bizjak <ubizjak@...il.com>, stable@...r.kernel.org,
	Fangrui Song <i@...kray.me>, Nathan Chancellor <nathan@...nel.org>,
	Andy Lutomirski <luto@...nel.org>
Subject: Re: [PATCH v5 01/16] x86/stackprotector: Work around strict Clang
 TLS symbol requirements

On 11/05, Brian Gerst wrote:
>
> --- a/arch/x86/kernel/vmlinux.lds.S
> +++ b/arch/x86/kernel/vmlinux.lds.S
> @@ -468,6 +468,9 @@ SECTIONS
>  . = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
>  	   "kernel image bigger than KERNEL_IMAGE_SIZE");
>
> +/* needed for Clang - see arch/x86/entry/entry.S */
> +PROVIDE(__ref_stack_chk_guard = __stack_chk_guard);

Don't we need the simple fix below?

without this patch I can't build the kernel with CONFIG_STACKPROTECTOR=n.

Oleg.

diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S
index fab3ac9a4574..2ff48645bab9 100644
--- a/arch/x86/kernel/vmlinux.lds.S
+++ b/arch/x86/kernel/vmlinux.lds.S
@@ -472,8 +472,10 @@ SECTIONS
 . = ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
 	   "kernel image bigger than KERNEL_IMAGE_SIZE");
 
+#ifdef CONFIG_STACKPROTECTOR
 /* needed for Clang - see arch/x86/entry/entry.S */
 PROVIDE(__ref_stack_chk_guard = __stack_chk_guard);
+#endif
 
 #ifdef CONFIG_X86_64
 /*