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| author | Vincenzo Frascino <vincenzo.frascino@arm.com> | 2021-01-26 16:40:56 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-02-07 17:37:12 +0300 |
| commit | 25fd5f8f8a234d6ca0c7f71b65a59092b6d4a5f7 (patch) | |
| tree | b0be6df2ac82984f4d8f27992cc55fe14b1f9d84 /arch | |
| parent | beba2ac6b1205e614b7a39c3f9b0718c38fa57e7 (diff) | |
| download | linux-25fd5f8f8a234d6ca0c7f71b65a59092b6d4a5f7.tar.xz | |
arm64: Fix kernel address detection of __is_lm_address()
commit 519ea6f1c82fcdc9842908155ae379de47818778 upstream.
Currently, the __is_lm_address() check just masks out the top 12 bits
of the address, but if they are 0, it still yields a true result.
This has as a side effect that virt_addr_valid() returns true even for
invalid virtual addresses (e.g. 0x0).
Fix the detection checking that it's actually a kernel address starting
at PAGE_OFFSET.
Fixes: 68dd8ef32162 ("arm64: memory: Fix virt_addr_valid() using __is_lm_address()")
Cc: <stable@vger.kernel.org> # 5.4.x
Cc: Will Deacon <will@kernel.org>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20210126134056.45747-1-vincenzo.frascino@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/arm64/include/asm/memory.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index cd61239bae8c..8f3020bb75ef 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -238,11 +238,11 @@ static inline const void *__tag_set(const void *addr, u8 tag) /* - * The linear kernel range starts at the bottom of the virtual address - * space. Testing the top bit for the start of the region is a - * sufficient check and avoids having to worry about the tag. + * Check whether an arbitrary address is within the linear map, which + * lives in the [PAGE_OFFSET, PAGE_END) interval at the bottom of the + * kernel's TTBR1 address range. */ -#define __is_lm_address(addr) (!(((u64)addr) & BIT(vabits_actual - 1))) +#define __is_lm_address(addr) (((u64)(addr) ^ PAGE_OFFSET) < (PAGE_END - PAGE_OFFSET)) #define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET) #define __kimg_to_phys(addr) ((addr) - kimage_voffset) |