On Tue, 13 Mar 2018 17:55:53 +0900,
Huacai Chen wrote:

Hi, Yoshinori, Rich and SuperH developers,

I'm not familiar with SuperH assembly, but SuperH has the same bug
obviously. Could you please fix that?

Huacai

OK. Apply this fix.
SuperH can not handle long int directly.

diff --git a/arch/sh/boot/compressed/head_32.S b/arch/sh/boot/compressed/head_32.S
index a3fdb053f351..7411fcb5764a 100644
--- a/arch/sh/boot/compressed/head_32.S
+++ b/arch/sh/boot/compressed/head_32.S

@@ -76,8 +76,8 @@ l1:
 	mov.l	init_stack_addr, r0
 	mov.l	@r0, r15
 
-	mov.l	__stack_chk_guard, r0
-	mov	#0x000a0dff, r1
+	mov.l	__stack_chk_guard_ptr, r0
+	mov.l	__stack_chk_val, r1
 	mov.l	r1, @r0
 
 	/* Decompress the kernel */

@@ -109,6 +109,10 @@ kernel_start_addr:
 #else
 	.long	_text+PAGE_SIZE
 #endif
+__stack_chk_guard_ptr:
+	.long	__stack_chk_guard
+__stack_chk_val:
+	.long	0x000a0dff
 
 	.align	9
 fake_headers_as_bzImage:

On Mon, Mar 12, 2018 at 10:04 AM, Huacai Chen [off-list ref] wrote:

quoted

Call __stack_chk_guard_setup() in decompress_kernel() is too late that
stack checking always fails for decompress_kernel() itself. So remove
__stack_chk_guard_setup() and initialize __stack_chk_guard before we
call decompress_kernel().

Original code comes from ARM but also used for MIPS and SH, so fix them
together. If without this fix, compressed booting of these archs will
fail because stack checking is enabled by default (>=4.16).

V2: Fix build on ARM.

Cc: stable at vger.kernel.org
Signed-off-by: Huacai Chen <redacted>
---
 arch/arm/boot/compressed/head.S        | 4 ++++
 arch/arm/boot/compressed/misc.c        | 7 -------
 arch/mips/boot/compressed/decompress.c | 7 -------
 arch/mips/boot/compressed/head.S       | 4 ++++
 arch/sh/boot/compressed/head_32.S      | 4 ++++
 arch/sh/boot/compressed/head_64.S      | 4 ++++
 arch/sh/boot/compressed/misc.c         | 7 -------
 7 files changed, 16 insertions(+), 21 deletions(-)

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 45c8823..bae1fc6 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S

@@ -547,6 +547,10 @@ not_relocated:     mov     r0, #0
                bic     r4, r4, #1
                blne    cache_on

+               ldr     r0, =__stack_chk_guard
+               ldr     r1, =0x000a0dff
+               str     r1, [r0]
+
 /*
  * The C runtime environment should now be setup sufficiently.
  * Set up some pointers, and start decompressing.

diff --git a/arch/arm/boot/compressed/misc.c b/arch/arm/boot/compressed/misc.c
index 16a8a80..e518ef5 100644
--- a/arch/arm/boot/compressed/misc.c
+++ b/arch/arm/boot/compressed/misc.c

@@ -130,11 +130,6 @@ asmlinkage void __div0(void)

 unsigned long __stack_chk_guard;

-void __stack_chk_guard_setup(void)
-{
-       __stack_chk_guard = 0x000a0dff;
-}
-
 void __stack_chk_fail(void)
 {
        error("stack-protector: Kernel stack is corrupted\n");

@@ -150,8 +145,6 @@ decompress_kernel(unsigned long output_start, unsigned long free_mem_ptr_p,
 {
        int ret;

-       __stack_chk_guard_setup();
-
        output_data             = (unsigned char *)output_start;
        free_mem_ptr            = free_mem_ptr_p;
        free_mem_end_ptr        = free_mem_ptr_end_p;

diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c
index fdf99e9..5ba431c 100644
--- a/arch/mips/boot/compressed/decompress.c
+++ b/arch/mips/boot/compressed/decompress.c

@@ -78,11 +78,6 @@ void error(char *x)

 unsigned long __stack_chk_guard;

-void __stack_chk_guard_setup(void)
-{
-       __stack_chk_guard = 0x000a0dff;
-}
-
 void __stack_chk_fail(void)
 {
        error("stack-protector: Kernel stack is corrupted\n");

@@ -92,8 +87,6 @@ void decompress_kernel(unsigned long boot_heap_start)
 {
        unsigned long zimage_start, zimage_size;

-       __stack_chk_guard_setup();
-
        zimage_start = (unsigned long)(&__image_begin);
        zimage_size = (unsigned long)(&__image_end) -
            (unsigned long)(&__image_begin);

diff --git a/arch/mips/boot/compressed/head.S b/arch/mips/boot/compressed/head.S
index 409cb48..00d0ee0 100644
--- a/arch/mips/boot/compressed/head.S
+++ b/arch/mips/boot/compressed/head.S

@@ -32,6 +32,10 @@ start:
        bne     a2, a0, 1b
         addiu  a0, a0, 4

+       PTR_LA  a0, __stack_chk_guard
+       PTR_LI  a1, 0x000a0dff
+       sw      a1, 0(a0)
+
        PTR_LA  a0, (.heap)          /* heap address */
        PTR_LA  sp, (.stack + 8192)  /* stack address */

diff --git a/arch/sh/boot/compressed/head_32.S b/arch/sh/boot/compressed/head_32.S
index 7bb1681..a3fdb05 100644
--- a/arch/sh/boot/compressed/head_32.S
+++ b/arch/sh/boot/compressed/head_32.S

@@ -76,6 +76,10 @@ l1:
        mov.l   init_stack_addr, r0
        mov.l   @r0, r15

+       mov.l   __stack_chk_guard, r0
+       mov     #0x000a0dff, r1
+       mov.l   r1, @r0
+
        /* Decompress the kernel */
        mov.l   decompress_kernel_addr, r0
        jsr     @r0

diff --git a/arch/sh/boot/compressed/head_64.S b/arch/sh/boot/compressed/head_64.S
index 9993113..8b4d540 100644
--- a/arch/sh/boot/compressed/head_64.S
+++ b/arch/sh/boot/compressed/head_64.S

@@ -132,6 +132,10 @@ startup:
        addi    r22, 4, r22
        bne     r22, r23, tr1

+       movi    datalabel __stack_chk_guard, r0
+       movi    0x000a0dff, r1
+       st.l    r0, 0, r1
+
        /*
         * Decompress the kernel.
         */

diff --git a/arch/sh/boot/compressed/misc.c b/arch/sh/boot/compressed/misc.c
index 627ce8e..fe4c079 100644
--- a/arch/sh/boot/compressed/misc.c
+++ b/arch/sh/boot/compressed/misc.c

@@ -106,11 +106,6 @@ static void error(char *x)

 unsigned long __stack_chk_guard;

-void __stack_chk_guard_setup(void)
-{
-       __stack_chk_guard = 0x000a0dff;
-}
-
 void __stack_chk_fail(void)
 {
        error("stack-protector: Kernel stack is corrupted\n");

@@ -130,8 +125,6 @@ void decompress_kernel(void)
 {
        unsigned long output_addr;

-       __stack_chk_guard_setup();
-
 #ifdef CONFIG_SUPERH64
        output_addr = (CONFIG_MEMORY_START + 0x2000);
 #else
--

2.7.0

--
Yoshinori Sato
[off-list ref]