[PATCH 0/6] tools/nolibc: add stackprotector support for more architectures

[PATCH 0/6] tools/nolibc: add stackprotector support for more architectures

[Thomas Weißschuh]

Add stackprotector support for all remaining architectures, except s390.

On s390 the stackprotectors are not supported in "global" mode; only
"sysreg" mode which is not suppored in nolibc.

The series also contains a small optimization to strace output during
execution of nolibc-test.

This series is based on the 20230415-nolibc-updates-4a branch of the
nolibc tree.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
Thomas Weißschuh (6):
      selftests/nolibc: reduce syscalls during space padding
      tools/nolibc: riscv: add stackprotector support
      tools/nolibc: aarch64: add stackprotector support
      tools/nolibc: arm: add stackprotector support
      tools/nolibc: loongarch: add stackprotector support
      tools/nolibc: mips: add stackprotector support

 tools/include/nolibc/arch-aarch64.h          |  7 ++++++-
 tools/include/nolibc/arch-arm.h              |  7 ++++++-
 tools/include/nolibc/arch-loongarch.h        |  7 ++++++-
 tools/include/nolibc/arch-mips.h             |  8 +++++++-
 tools/include/nolibc/arch-riscv.h            |  7 ++++++-
 tools/testing/selftests/nolibc/Makefile      |  5 +++++
 tools/testing/selftests/nolibc/nolibc-test.c | 15 +++++++++++----
 7 files changed, 47 insertions(+), 9 deletions(-)
---
base-commit: e35214ea9db7477a02e67a8b412e8046534bb97c
change-id: 20230408-nolibc-stackprotector-archs-42244674616e

Best regards,
-- 
Thomas Weißschuh <linux@weissschuh.net>

[PATCH 1/6] selftests/nolibc: reduce syscalls during space padding

[Thomas Weißschuh]

Previously each space character used for alignment during test execution
was written in a single write() call.
This would make the output from strace fairly unreadable.
Coalesce all spaces into a single call to write().

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/testing/selftests/nolibc/nolibc-test.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c
index 68e22617651c..35f203556a0c 100644
--- a/tools/testing/selftests/nolibc/nolibc-test.c
+++ b/tools/testing/selftests/nolibc/nolibc-test.c
@@ -108,19 +108,26 @@ const char *errorname(int err)
 	}
 }
 
+static void putcharn(char c, size_t n)
+{
+	char buf[64];
+
+	memset(buf, c, n);
+	buf[n] = '\0';
+	fputs(buf, stdout);
+}
+
 static int pad_spc(int llen, int cnt, const char *fmt, ...)
 {
 	va_list args;
-	int len;
 	int ret;
 
-	for (len = 0; len < cnt - llen; len++)
-		putchar(' ');
+	putcharn(' ', cnt - llen);
 
 	va_start(args, fmt);
 	ret = vfprintf(stdout, fmt, args);
 	va_end(args);
-	return ret < 0 ? ret : ret + len;
+	return ret < 0 ? ret : ret + cnt - llen;
 }
 
 /* The tests below are intended to be used by the macroes, which evaluate

-- 
2.40.0

[PATCH 2/6] tools/nolibc: riscv: add stackprotector support

[Thomas Weißschuh]

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-riscv.h       | 7 ++++++-
 tools/testing/selftests/nolibc/Makefile | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h
index 0d5f15fdedc4..b2ccffcc079f 100644
--- a/tools/include/nolibc/arch-riscv.h
+++ b/tools/include/nolibc/arch-riscv.h
@@ -173,14 +173,19 @@ struct sys_stat_struct {
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
+#define __ARCH_SUPPORTS_STACK_PROTECTOR
+
 /* startup code */
-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 (
 		".option push\n"
 		".option norelax\n"
 		"lla   gp, __global_pointer$\n"
 		".option pop\n"
+#ifdef NOLIBC_STACKPROTECTOR
+		"call __stack_chk_init\n"    /* initialize stack protector                          */
+#endif
 		"lw    a0, 0(sp)\n"          /* argc (a0) was in the stack                          */
 		"add   a1, sp, "SZREG"\n"    /* argv (a1) = sp                                      */
 		"slli  a2, a0, "PTRLOG"\n"   /* envp (a2) = SZREG*argc ...                          */
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 3c8e3a6f8985..0a83ad388a16 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -82,6 +82,7 @@ CFLAGS_STACKPROTECTOR = -DNOLIBC_STACKPROTECTOR \
 CFLAGS_STKP_i386 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
+CFLAGS_STKP_riscv = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64
 CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \
 		$(call cc-option,-fno-stack-protector) \

-- 
2.40.0

[PATCH 3/6] tools/nolibc: aarch64: add stackprotector support

[Thomas Weißschuh]

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-aarch64.h     | 7 ++++++-
 tools/testing/selftests/nolibc/Makefile | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-aarch64.h b/tools/include/nolibc/arch-aarch64.h
index 76ef26520c85..6a859131c530 100644
--- a/tools/include/nolibc/arch-aarch64.h
+++ b/tools/include/nolibc/arch-aarch64.h
@@ -172,10 +172,15 @@ struct sys_stat_struct {
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
+#define __ARCH_SUPPORTS_STACK_PROTECTOR
+
 /* startup code */
-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 (
+#ifdef NOLIBC_STACKPROTECTOR
+		"bl __stack_chk_init\n"   /* initialize stack protector                     */
+#endif
 		"ldr x0, [sp]\n"     /* argc (x0) was in the stack                          */
 		"add x1, sp, 8\n"    /* argv (x1) = sp                                      */
 		"lsl x2, x0, 3\n"    /* envp (x2) = 8*argc ...                              */
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 0a83ad388a16..d68e96afea80 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -82,6 +82,7 @@ CFLAGS_STACKPROTECTOR = -DNOLIBC_STACKPROTECTOR \
 CFLAGS_STKP_i386 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
+CFLAGS_STKP_arm64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_riscv = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64
 CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \

-- 
2.40.0

[PATCH 4/6] tools/nolibc: arm: add stackprotector support

[Thomas Weißschuh]

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-arm.h         | 7 ++++++-
 tools/testing/selftests/nolibc/Makefile | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-arm.h b/tools/include/nolibc/arch-arm.h
index 2eab1aef321b..202e64f537dc 100644
--- a/tools/include/nolibc/arch-arm.h
+++ b/tools/include/nolibc/arch-arm.h
@@ -199,10 +199,15 @@ struct sys_stat_struct {
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
+#define __ARCH_SUPPORTS_STACK_PROTECTOR
+
 /* startup code */
-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 (
+#ifdef NOLIBC_STACKPROTECTOR
+		"bl __stack_chk_init\n"       /* initialize stack protector                          */
+#endif
 		"pop {%r0}\n"                 /* argc was in the stack                               */
 		"mov %r1, %sp\n"              /* argv = sp                                           */
 
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index d68e96afea80..8feffc790a31 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -83,6 +83,7 @@ CFLAGS_STKP_i386 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_arm64 = $(CFLAGS_STACKPROTECTOR)
+CFLAGS_STKP_arm = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_riscv = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64
 CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \

-- 
2.40.0

[PATCH 5/6] tools/nolibc: loongarch: add stackprotector support

[Thomas Weißschuh]

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 tools/include/nolibc/arch-loongarch.h   | 7 ++++++-
 tools/testing/selftests/nolibc/Makefile | 1 +
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/tools/include/nolibc/arch-loongarch.h b/tools/include/nolibc/arch-loongarch.h
index ec3b46a991a9..07e3b1fd7262 100644
--- a/tools/include/nolibc/arch-loongarch.h
+++ b/tools/include/nolibc/arch-loongarch.h
@@ -149,6 +149,8 @@
 char **environ __attribute__((weak));
 const unsigned long *_auxv __attribute__((weak));
 
+#define __ARCH_SUPPORTS_STACK_PROTECTOR
+
 #if __loongarch_grlen == 32
 #define LONGLOG      "2"
 #define SZREG        "4"
@@ -170,9 +172,12 @@ const unsigned long *_auxv __attribute__((weak));
 #endif
 
 /* startup code */
-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 (
+#ifdef NOLIBC_STACKPROTECTOR
+		"bl __stack_chk_init\n"               /* initialize stack protector                          */
+#endif
 		REG_L        " $a0, $sp, 0\n"         /* argc (a0) was in the stack                          */
 		LONG_ADDI    " $a1, $sp, "SZREG"\n"   /* argv (a1) = sp + SZREG                              */
 		LONG_SLL     " $a2, $a0, "LONGLOG"\n" /* envp (a2) = SZREG*argc ...                          */
diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
index 8feffc790a31..efa7a51e0fcd 100644
--- a/tools/testing/selftests/nolibc/Makefile
+++ b/tools/testing/selftests/nolibc/Makefile
@@ -85,6 +85,7 @@ CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_arm64 = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_arm = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_riscv = $(CFLAGS_STACKPROTECTOR)
+CFLAGS_STKP_loongarch = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64
 CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \
 		$(call cc-option,-fno-stack-protector) \

-- 
2.40.0

[PATCH 6/6] tools/nolibc: mips: add stackprotector support

[Thomas Weißschuh]

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
---
 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 efa7a51e0fcd..a7524445f33c 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_riscv = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_STKP_loongarch = $(CFLAGS_STACKPROTECTOR)
 CFLAGS_s390 = -m64

-- 
2.40.0

Re: [PATCH 2/6] tools/nolibc: riscv: add stackprotector support

[Palmer Dabbelt]

On Mon, 17 Apr 2023 09:01:32 PDT (-0700), linux@weissschuh.net wrote:
> Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
> ---
>  tools/include/nolibc/arch-riscv.h       | 7 ++++++-
>  tools/testing/selftests/nolibc/Makefile | 1 +
>  2 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h
> index 0d5f15fdedc4..b2ccffcc079f 100644
> --- a/tools/include/nolibc/arch-riscv.h
> +++ b/tools/include/nolibc/arch-riscv.h
> @@ -173,14 +173,19 @@ struct sys_stat_struct {
>  char **environ __attribute__((weak));
>  const unsigned long *_auxv __attribute__((weak));
>
> +#define __ARCH_SUPPORTS_STACK_PROTECTOR
> +
>  /* startup code */
> -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 (
>  		".option push\n"
>  		".option norelax\n"
>  		"lla   gp, __global_pointer$\n"
>  		".option pop\n"
> +#ifdef NOLIBC_STACKPROTECTOR
> +		"call __stack_chk_init\n"    /* initialize stack protector                          */
> +#endif
>  		"lw    a0, 0(sp)\n"          /* argc (a0) was in the stack                          */
>  		"add   a1, sp, "SZREG"\n"    /* argv (a1) = sp                                      */
>  		"slli  a2, a0, "PTRLOG"\n"   /* envp (a2) = SZREG*argc ...                          */
> diff --git a/tools/testing/selftests/nolibc/Makefile b/tools/testing/selftests/nolibc/Makefile
> index 3c8e3a6f8985..0a83ad388a16 100644
> --- a/tools/testing/selftests/nolibc/Makefile
> +++ b/tools/testing/selftests/nolibc/Makefile
> @@ -82,6 +82,7 @@ CFLAGS_STACKPROTECTOR = -DNOLIBC_STACKPROTECTOR \
>  CFLAGS_STKP_i386 = $(CFLAGS_STACKPROTECTOR)
>  CFLAGS_STKP_x86_64 = $(CFLAGS_STACKPROTECTOR)
>  CFLAGS_STKP_x86 = $(CFLAGS_STACKPROTECTOR)
> +CFLAGS_STKP_riscv = $(CFLAGS_STACKPROTECTOR)
>  CFLAGS_s390 = -m64
>  CFLAGS  ?= -Os -fno-ident -fno-asynchronous-unwind-tables -std=c89 \
>  		$(call cc-option,-fno-stack-protector) \

Acked-by: Palmer Dabbelt <palmer@rivosinc.com>