c128d5281f
The "SCSI Block Commands - 2" (SBC-2) standard defines bits [7:5] of the CDB byte 1 as Reserved, for the READ and WRITE commands. The updated "SCSI Block Commands - 3" (SBC-3) standard defines the same bitfield as RDPROTECT and WRPROTECT, respectively. After reviewing the above standards, and the following commits: - SVN r8331 (git676e2a32), - SVN r8334 (git6b3ecf5c), we've determined that UefiScsiLib is incorrect in encoding the LUN in this bitfield for the READ and WRITE commands. Encoding a nonzero LUN there creates unintended RDPROTECT and WRPROTECT values, which the recipient device is required to reject if it does not support protection information, with CHECK CONDITION, ILLEGAL REQUEST, INVALID FIELD IN CDB: ScsiDiskRead10: Check Condition happened! ScsiDisk: Sense Key = 0x5 ASC = 0x24! ScsiDiskRead10: Check Condition happened! ScsiDisk: Sense Key = 0x5 ASC = 0x24! ScsiDiskRead10: Check Condition happened! ScsiDisk: Sense Key = 0x5 ASC = 0x24! ScsiDiskRead10: Check Condition happened! ScsiDisk: Sense Key = 0x5 ASC = 0x24! FatOpenDevice: read of part_lba failed Device Error In practice this flaw breaks UefiScsiLib minimally on SCSI disks with nonzero LUNs that are emulated by QEMU (after QEMU commit 96bdbbab, part of v1.2.0). RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1166971 Reported-by: Cole Robinson <crobinso@redhat.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Suggested-by: Feng Tian <feng.tian@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Liming Gao <liming.gao@intel.com> git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16454 6f19259b-4bc3-4df7-8a09-765794883524