From: "Russell King (Oracle)" rmk+kernel@armlinux.org.uk
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=...
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commit 04e91b7324760a377a725e218b5ee783826d30f5 upstream.
Provide a couple of helpers to copy the vectors and stubs, and also to flush the copied vectors and stubs.
Acked-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: Russell King (Oracle) rmk+kernel@armlinux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Chen Jiahao chenjiahao16@huawei.com Reviewed-by: Liao Chang liaochang1@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- arch/arm/kernel/traps.c | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-)
diff --git a/arch/arm/kernel/traps.c b/arch/arm/kernel/traps.c index 17d5a785df28..e9ad5f844781 100644 --- a/arch/arm/kernel/traps.c +++ b/arch/arm/kernel/traps.c @@ -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