From 5cc7f92989bdccf376926e33dc509c09da0bac79 Mon Sep 17 00:00:00 2001 From: Yanjun Yang Date: Tue, 11 Jun 2024 18:09:47 +0800 Subject: [PATCH] ARM: Remove address checking for MMUless devices commit 3ccea4784fddd96fbd6c4497eb28b45dab638c2a upstream. Commit 169f9102f9198b ("ARM: 9350/1: fault: Implement copy_from_kernel_nofault_allowed()") added the function to check address before use. However, for devices without MMU, addr > TASK_SIZE will always fail. This patch move this function after the #ifdef CONFIG_MMU statement. Signed-off-by: Yanjun Yang Acked-by: Ard Biesheuvel Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218953 Fixes: 169f9102f9198b ("ARM: 9350/1: fault: Implement copy_from_kernel_nofault_allowed()") Link: https://lore.kernel.org/r/20240611100947.32241-1-yangyj.ee@gmail.com Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- arch/arm/mm/fault.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 97590ca80acdc..bf1577216ffab 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -24,6 +24,8 @@ #include "fault.h" +#ifdef CONFIG_MMU + bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size) { unsigned long addr = (unsigned long)unsafe_src; @@ -31,8 +33,6 @@ bool copy_from_kernel_nofault_allowed(const void *unsafe_src, size_t size) return addr >= TASK_SIZE && ULONG_MAX - addr >= size; } -#ifdef CONFIG_MMU - /* * This is useful to dump out the page tables associated with * 'addr' in mm 'mm'. -- 2.47.3