Commit ad1936b5 authored by Russell King (Oracle)'s avatar Russell King (Oracle) Committed by Zheng Zengkai
Browse files

ARM: early traps initialisation 

stable inclusion
from stable-v5.10.105
commit 46deb224680bb33c8e87440a7b909d16e5a7d7c5
category: bugfix
bugzilla: 186460 https://gitee.com/src-openeuler/kernel/issues/I53MHA
CVE: CVE-2022-23960

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=46deb224680b



--------------------------------

commit 04e91b73 upstream.

Provide a couple of helpers to copy the vectors and stubs, and also
to flush the copied vectors and stubs.

Acked-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: default avatarRussell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarChen Jiahao <chenjiahao16@huawei.com>
Reviewed-by: default avatarLiao Chang <liaochang1@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent 0c240cda

arch/arm/kernel/traps.c

+21 −6
Original line number Diff line number Diff line
@@ -806,10 +806,22 @@ static inline void __init kuser_init(void *vectors) 
}

#endif



#ifndef CONFIG_CPU_V7M

static void copy_from_lma(void *vma, void *lma_start, void *lma_end)

{

	memcpy(vma, lma_start, lma_end - lma_start);

}



static void flush_vectors(void *vma, size_t offset, size_t size)

{

	unsigned long start = (unsigned long)vma + offset;

	unsigned long end = start + size;



	flush_icache_range(start, end);

}



void __init early_trap_init(void *vectors_base)

{

#ifndef CONFIG_CPU_V7M

	unsigned long vectors = (unsigned long)vectors_base;

	extern char __stubs_start[], __stubs_end[];

	extern char __vectors_start[], __vectors_end[];

	unsigned i;
@@ -830,17 +842,20 @@ void __init early_trap_init(void *vectors_base) 
	 * into the vector page, mapped at 0xffff0000, and ensure these

	 * are visible to the instruction stream.

	 */

	memcpy((void *)vectors, __vectors_start, __vectors_end - __vectors_start);

	memcpy((void *)vectors + 0x1000, __stubs_start, __stubs_end - __stubs_start);

	copy_from_lma(vectors_base, __vectors_start, __vectors_end);

	copy_from_lma(vectors_base + 0x1000, __stubs_start, __stubs_end);



	kuser_init(vectors_base);



	flush_icache_range(vectors, vectors + PAGE_SIZE * 2);

	flush_vectors(vectors_base, 0, PAGE_SIZE * 2);

}

#else /* ifndef CONFIG_CPU_V7M */

void __init early_trap_init(void *vectors_base)

{

	/*

	 * on V7-M there is no need to copy the vector table to a dedicated

	 * memory area. The address is configurable and so a table in the kernel

	 * image can be used.

	 */

#endif

}

#endif