The patch titled Subject: zboot: fix stack protector in compressed boot phase has been added to the -mm tree. Its filename is zboot-fix-stack-protector-in-compressed-boot-phase.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/zboot-fix-stack-protector-in-compressed-boot-phase.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/zboot-fix-stack-protector-in-compressed-boot-phase.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Huacai Chen <chenhc@xxxxxxxxxx> Subject: zboot: fix stack protector in compressed boot phase Calling __stack_chk_guard_setup() in decompress_kernel() is too late, so 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). Link: http://lkml.kernel.org/r/1521186916-13745-1-git-send-email-chenhc@xxxxxxxxxx Signed-off-by: Huacai Chen <chenhc@xxxxxxxxxx> Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx> Cc: James Hogan <james.hogan@xxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- 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 | 8 ++++++++ arch/sh/boot/compressed/head_64.S | 4 ++++ arch/sh/boot/compressed/misc.c | 7 ------- 7 files changed, 20 insertions(+), 21 deletions(-) diff -puN arch/arm/boot/compressed/head.S~zboot-fix-stack-protector-in-compressed-boot-phase arch/arm/boot/compressed/head.S --- a/arch/arm/boot/compressed/head.S~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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 -puN arch/arm/boot/compressed/misc.c~zboot-fix-stack-protector-in-compressed-boot-phase arch/arm/boot/compressed/misc.c --- a/arch/arm/boot/compressed/misc.c~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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_s { 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 -puN arch/mips/boot/compressed/decompress.c~zboot-fix-stack-protector-in-compressed-boot-phase arch/mips/boot/compressed/decompress.c --- a/arch/mips/boot/compressed/decompress.c~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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 boo { 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 -puN arch/mips/boot/compressed/head.S~zboot-fix-stack-protector-in-compressed-boot-phase arch/mips/boot/compressed/head.S --- a/arch/mips/boot/compressed/head.S~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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 -puN arch/sh/boot/compressed/head_32.S~zboot-fix-stack-protector-in-compressed-boot-phase arch/sh/boot/compressed/head_32.S --- a/arch/sh/boot/compressed/head_32.S~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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_addr, r0 + mov.l __stack_chk_guard_val, r1 + mov.l r1, @r0 + /* Decompress the kernel */ mov.l decompress_kernel_addr, r0 jsr @r0 @@ -97,6 +101,10 @@ kexec_magic: .long 0x400000F0 /* magic used by kexec to parse zImage format */ init_stack_addr: .long stack_start +__stack_chk_guard_val: + .long 0x000A0DFF +__stack_chk_guard_addr: + .long __stack_chk_guard decompress_kernel_addr: .long decompress_kernel kernel_start_addr: diff -puN arch/sh/boot/compressed/head_64.S~zboot-fix-stack-protector-in-compressed-boot-phase arch/sh/boot/compressed/head_64.S --- a/arch/sh/boot/compressed/head_64.S~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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 -puN arch/sh/boot/compressed/misc.c~zboot-fix-stack-protector-in-compressed-boot-phase arch/sh/boot/compressed/misc.c --- a/arch/sh/boot/compressed/misc.c~zboot-fix-stack-protector-in-compressed-boot-phase +++ a/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 _ Patches currently in -mm which might be from chenhc@xxxxxxxxxx are zboot-fix-stack-protector-in-compressed-boot-phase.patch