linux-kernel - [PATCH RFC 17/43] x86/pie: Enable stack protector only if per-cpu stack canary is supported

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: <dbf5865f3d03805ee2e9062d03d359e551b6e9ba.1682673543.git.houwenlong.hwl@antgroup.com>
Date:   Fri, 28 Apr 2023 17:50:57 +0800
From:   "Hou Wenlong" <houwenlong.hwl@...group.com>
To:     linux-kernel@...r.kernel.org
Cc:     "Thomas Garnier" <thgarnie@...omium.org>,
        "Lai Jiangshan" <jiangshan.ljs@...group.com>,
        "Kees Cook" <keescook@...omium.org>,
        "Hou Wenlong" <houwenlong.hwl@...group.com>,
        "Thomas Gleixner" <tglx@...utronix.de>,
        "Ingo Molnar" <mingo@...hat.com>, "Borislav Petkov" <bp@...en8.de>,
        "Dave Hansen" <dave.hansen@...ux.intel.com>, <x86@...nel.org>,
        "H. Peter Anvin" <hpa@...or.com>
Subject: [PATCH RFC 17/43] x86/pie: Enable stack protector only if per-cpu stack canary is supported

Since -fPIE option is not incompatible with -mcmode=kernel option, PIE
kernel would drop -mcmodel=kernel option. However, GCC would use %fs as
segment register for stack protector when -mcmodel=kernel option is
dropped. So only enable stack protector for PIE kernel if per-cpu stack
canary is supported.

Signed-off-by: Hou Wenlong <houwenlong.hwl@...group.com>
Cc: Thomas Garnier <thgarnie@...omium.org>
Cc: Lai Jiangshan <jiangshan.ljs@...group.com>
Cc: Kees Cook <keescook@...omium.org>
---
 arch/x86/Kconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 55cce8cdf9bd..b26941ef50ee 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -403,6 +403,7 @@ config PGTABLE_LEVELS
 
 config CC_HAS_SANE_STACKPROTECTOR
 	bool
+	default CC_HAS_CUSTOMIZED_STACKPROTECTOR if X86_PIE
 	default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC) $(CLANG_FLAGS)) if 64BIT
 	default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC) $(CLANG_FLAGS))
 	help
-- 
2.31.1