https://git.reactos.org/?p=reactos.git;a=commitdiff;h=3d980c4a2c8786bfc1a4fd4a48f8c2c5825db1ff
commit 3d980c4a2c8786bfc1a4fd4a48f8c2c5825db1ff Author: Hermès Bélusca-Maïto <[email protected]> AuthorDate: Mon Dec 7 22:52:42 2020 +0100 Commit: Hermès Bélusca-Maïto <[email protected]> CommitDate: Mon Dec 7 22:52:42 2020 +0100 [NTOS:FSTUB] Addendum to 29615fee and 8d2fe541: Further remove useless casts. Also, fix the MBR checksum calculation (missing ~CheckSum + 1), to fix the calculation in accordance with how MS calculates the MBR checksums (and what we do as well in https://github.com/reactos/reactos/blob/master/base/setup/lib/utils/partlist.c#L1581 https://github.com/reactos/reactos/blob/master/boot/freeldr/freeldr/arch/i386/hwdisk.c#L291 ). --- ntoskrnl/fstub/fstubex.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/ntoskrnl/fstub/fstubex.c b/ntoskrnl/fstub/fstubex.c index 16787bbd4df..84296e0a722 100644 --- a/ntoskrnl/fstub/fstubex.c +++ b/ntoskrnl/fstub/fstubex.c @@ -909,7 +909,7 @@ FstubReadHeaderEFI(IN PDISK_INFORMATION Disk, Status = FstubReadSector(Disk->DeviceObject, Disk->SectorSize, EFIHeader->PartitionEntryLBA + i, - (PUSHORT)Sector); + Sector); if (!NT_SUCCESS(Status)) { ExFreePoolWithTag(Sector, TAG_FSTUB); @@ -929,7 +929,7 @@ FstubReadHeaderEFI(IN PDISK_INFORMATION Disk, Status = FstubReadSector(Disk->DeviceObject, Disk->SectorSize, EFIHeader->PartitionEntryLBA + i, - (PUSHORT)Sector); + Sector); if (!NT_SUCCESS(Status)) { ExFreePoolWithTag(Sector, TAG_FSTUB); @@ -2189,7 +2189,7 @@ IoReadDiskSignature(IN PDEVICE_OBJECT DeviceObject, Status = FstubReadSector(DeviceObject, BytesPerSector, 0ULL, - (PUSHORT)Buffer); + Buffer); if (!NT_SUCCESS(Status)) { goto Cleanup; @@ -2208,7 +2208,7 @@ IoReadDiskSignature(IN PDEVICE_OBJECT DeviceObject, Status = FstubReadSector(DeviceObject, BytesPerSector, 1ULL, - (PUSHORT)Buffer); + Buffer); if (!NT_SUCCESS(Status)) { goto Cleanup; @@ -2245,10 +2245,11 @@ IoReadDiskSignature(IN PDEVICE_OBJECT DeviceObject, else { /* Compute MBR checksum */ - for (i = 0, CheckSum = 0; i < 512; i += sizeof(INT32)) + for (i = 0, CheckSum = 0; i < 512; i += sizeof(UINT32)) { CheckSum += *(PUINT32)&Buffer[i]; } + CheckSum = ~CheckSum + 1; /* Set partition table style to MBR and return signature (offset 440) and checksum */ Signature->PartitionStyle = PARTITION_STYLE_MBR;
