From 699372d388a796441d938dba4fdb6525b69ea250 Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Mon, 6 Feb 2023 19:29:09 +0100 Subject: [PATCH] ArmPkg/CpuDxe ARM: Fix page-to-section attribute conversion The section-to-page attribute conversion takes the shareability and execute-never attributes into account, whereas the page-to-section counterpart does not. The result is that GetMemoryRegionPage () -which takes a section attribute argument (via *RegionAttributes) that is ostensibly based on the first page in the range, but differs from the actual page attributes when converted back- may return with a RegionLength of zero. This is incorrect, and confuses code that scans a region by calling GetMemoryRegion () in sequence. So fix the conversion, and ASSERT () on a non-zero region length. Signed-off-by: Ard Biesheuvel Reviewed-by: Leif Lindholm --- ArmPkg/Drivers/CpuDxe/Arm/Mmu.c | 3 +++ ArmPkg/Include/Chipset/ArmV7Mmu.h | 2 ++ 2 files changed, 5 insertions(+) diff --git a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c index ea856f5cdd..8eb1f71395 100644 --- a/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c +++ b/ArmPkg/Drivers/CpuDxe/Arm/Mmu.c @@ -480,6 +480,8 @@ GetMemoryRegion ( PageAttributes = PageTable[PageTableIndex] & TT_DESCRIPTOR_PAGE_ATTRIBUTE_MASK; *RegionAttributes = TT_DESCRIPTOR_CONVERT_TO_SECTION_CACHE_POLICY (PageAttributes) | + TT_DESCRIPTOR_CONVERT_TO_SECTION_S (PageAttributes) | + TT_DESCRIPTOR_CONVERT_TO_SECTION_XN (PageAttributes) | TT_DESCRIPTOR_CONVERT_TO_SECTION_AP (PageAttributes); } @@ -494,6 +496,7 @@ GetMemoryRegion ( // Scan the page table to find the end of the region. Status = GetMemoryRegionPage (PageTable, BaseAddress, RegionLength, RegionAttributes); + ASSERT (*RegionLength > 0); // If we have found the end of the region (Status == EFI_SUCCESS) then we exit the for-loop if (Status == EFI_SUCCESS) { diff --git a/ArmPkg/Include/Chipset/ArmV7Mmu.h b/ArmPkg/Include/Chipset/ArmV7Mmu.h index 6a2584ceb3..e0219747df 100644 --- a/ArmPkg/Include/Chipset/ArmV7Mmu.h +++ b/ArmPkg/Include/Chipset/ArmV7Mmu.h @@ -128,6 +128,8 @@ #define TT_DESCRIPTOR_CONVERT_TO_PAGE_CACHE_POLICY(Desc) ((((Desc) & (0x3 << 12)) >> 6) | (Desc & (0x3 << 2))) #define TT_DESCRIPTOR_CONVERT_TO_SECTION_AP(Desc) ((((Desc) & TT_DESCRIPTOR_PAGE_AP_MASK) << 6) & TT_DESCRIPTOR_SECTION_AP_MASK) +#define TT_DESCRIPTOR_CONVERT_TO_SECTION_S(Desc) ((((Desc) & TT_DESCRIPTOR_PAGE_S_MASK) << 6) & TT_DESCRIPTOR_SECTION_S_MASK) +#define TT_DESCRIPTOR_CONVERT_TO_SECTION_XN(Desc) ((((Desc) & TT_DESCRIPTOR_PAGE_XN_MASK) << 4) & TT_DESCRIPTOR_SECTION_XN_MASK) #define TT_DESCRIPTOR_CONVERT_TO_SECTION_CACHE_POLICY(Desc) ((((Desc) & (0x3 << 6)) << 6) | (Desc & (0x3 << 2))) #define TT_DESCRIPTOR_SECTION_ATTRIBUTE_MASK (TT_DESCRIPTOR_SECTION_NS_MASK | TT_DESCRIPTOR_SECTION_NG_MASK | \