Old filesystems (around 2008 and older) do not use CRC32c but rather CRC16-ANSI. Previously, the CalculateCrc16Ansi function was broken and gave us wrong checksums. Adapt to the new interface.
And while we're at it, fix the checksum algorithm itself - the crc16 algorithm just skips over the bg_checksum, and does not checksum it. This problem was found out-of-list when older ext4 filesystems (that use crc16 checksums) failed to mount with "corruption". BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4609 Signed-off-by: Pedro Falcato <pedro.falc...@gmail.com> Cc: Savva Mitrofanov <savva...@gmail.com> Cc: Marvin Häuser <mhaeu...@posteo.de> --- Features/Ext4Pkg/Ext4Dxe/BlockGroup.c | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-) diff --git a/Features/Ext4Pkg/Ext4Dxe/BlockGroup.c b/Features/Ext4Pkg/Ext4Dxe/BlockGroup.c index f34cdc5dbad7..d5642a5f155c 100644 --- a/Features/Ext4Pkg/Ext4Dxe/BlockGroup.c +++ b/Features/Ext4Pkg/Ext4Dxe/BlockGroup.c @@ -169,14 +169,10 @@ Ext4CalculateBlockGroupDescChecksumGdtCsum ( ) { UINT16 Csum; - UINT16 Dummy; - Dummy = 0; - - Csum = CalculateCrc16Ansi (Partition->SuperBlock.s_uuid, 16, 0); + Csum = CalculateCrc16Ansi (Partition->SuperBlock.s_uuid, 16, CRC16ANSI_INIT); Csum = CalculateCrc16Ansi (&BlockGroupNum, sizeof (BlockGroupNum), Csum); Csum = CalculateCrc16Ansi (BlockGroupDesc, OFFSET_OF (EXT4_BLOCK_GROUP_DESC, bg_checksum), Csum); - Csum = CalculateCrc16Ansi (&Dummy, sizeof (Dummy), Csum); Csum = CalculateCrc16Ansi ( &BlockGroupDesc->bg_block_bitmap_hi, -- 2.43.0 -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#111997): https://edk2.groups.io/g/devel/message/111997 Mute This Topic: https://groups.io/mt/102960519/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
