[PATCH 5.4 07/32] arm64: Do not pass tagged addresses to __is_lm_address()

From: Greg Kroah-Hartman
Date: Fri Feb 05 2021 - 17:16:16 EST


From: Catalin Marinas <catalin.marinas@xxxxxxx>

commit 91cb2c8b072e00632adf463b78b44f123d46a0fa upstream.

Commit 519ea6f1c82f ("arm64: Fix kernel address detection of
__is_lm_address()") fixed the incorrect validation of addresses below
PAGE_OFFSET. However, it no longer allowed tagged addresses to be passed
to virt_addr_valid().

Fix this by explicitly resetting the pointer tag prior to invoking
__is_lm_address(). This is consistent with the __lm_to_phys() macro.

Fixes: 519ea6f1c82f ("arm64: Fix kernel address detection of __is_lm_address()")
Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx>
Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # 5.4.x
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Vincenzo Frascino <vincenzo.frascino@xxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Link: https://lore.kernel.org/r/20210201190634.22942-2-catalin.marinas@xxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/arm64/include/asm/memory.h | 2 +-
arch/arm64/mm/physaddr.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)

--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -332,7 +332,7 @@ static inline void *phys_to_virt(phys_ad
#endif /* !CONFIG_SPARSEMEM_VMEMMAP || CONFIG_DEBUG_VIRTUAL */

#define virt_addr_valid(addr) ({ \
- __typeof__(addr) __addr = addr; \
+ __typeof__(addr) __addr = __tag_reset(addr); \
__is_lm_address(__addr) && pfn_valid(virt_to_pfn(__addr)); \
})

--- a/arch/arm64/mm/physaddr.c
+++ b/arch/arm64/mm/physaddr.c
@@ -9,7 +9,7 @@

phys_addr_t __virt_to_phys(unsigned long x)
{
- WARN(!__is_lm_address(x),
+ WARN(!__is_lm_address(__tag_reset(x)),
"virt_to_phys used for non-linear address: %pK (%pS)\n",
(void *)x,
(void *)x);