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ARM: Remove address checking for MMUless devices

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Commit 169f9102f9 ("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 <yangyj.ee@gmail.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218953
Fixes: 169f9102f9 ("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 <kees@kernel.org>
This commit is contained in:
Yanjun Yang 2024-06-11 18:09:47 +08:00 committed by Kees Cook
parent 18c18b1ff6
commit 3ccea4784f
1 changed files with 2 additions and 2 deletions
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4
arch/arm/mm/fault.c
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@ -25,6 +25,8 @@
#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;
@ -32,8 +34,6 @@ 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'.