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From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     linux-kernel@vger.kernel.org
Cc:     gwml@vger.gnuweeb.org, kernel-team@meta.com, w@lwt.eu,
        =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= <linux@weissschuh.net>,
        Willy Tarreau <w@1wt.eu>,
        "Paul E . McKenney" <paulmck@kernel.org>
Subject: [PATCH v2 nolibc 23/53] tools/nolibc: mips: add stackprotector support
Date:   Mon, 12 Jun 2023 13:44:44 -0700
Message-Id: <20230612204514.292087-23-paulmck@kernel.org>
In-Reply-To: <8b757cc0-3719-4e63-a755-9710384137bc@paulmck-laptop>
References: <8b757cc0-3719-4e63-a755-9710384137bc@paulmck-laptop>
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From: Thomas Weißschuh <linux@weissschuh.net>

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
 tools/include/nolibc/arch-mips.h        | 8 +++++++-
 tools/testing/selftests/nolibc/Makefile | 1 +
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-mips.h b/tools/include/nolibc/arch-mips.h
index 8822f150e72f..65c19ccc7f9d 100644
--- a/tools/include/nolibc/arch-mips.h
+++ b/tools/include/nolibc/arch-mips.h
@@ -179,14 +179,20 @@ struct sys_stat_struct {
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
+#define __ARCH_SUPPORTS_STACK_PROTECTOR
+
 /* startup code, note that it's called __start on MIPS */
-void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __start(void)
+void __attribute__((weak,noreturn,optimize("omit-frame-pointer"),no_stack_protector)) __start(void)
 {
 	__asm__ volatile (
 		/*".set nomips16\n"*/
 		".set push\n"
 		".set    noreorder\n"
 		".option pic0\n"
+#ifdef NOLIBC_STACKPROTECTOR
+		"jal __stack_chk_init\n" /* initialize stack protector                         */
+		"nop\n"                  /* delayed slot                                       */
+#endif
 		/*".ent __start\n"*/
 		/*"__start:\n"*/
 		"lw $a0,($sp)\n"        /* argc was in the stack                               */
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index ab6e7c0c2494..6d660d922240 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -84,6 +84,7 @@ CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_arm64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_arm = $(CFLAGS_STACKPROTECTOR)
+CFLAGS_STKP_mips = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_loongarch = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64
 CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \
-- 
2.40.1