In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Reject non-SCSI SRB on status IOCB fast path
qla2x00_status_entry() filters out non-TYPE_SRB entries and the
SRB_NVME_CMD, SRB_BIDI_CMD and SRB_TM_CMD types, then falls through to a
SCSI fast path that assumes the command is an SRB_SCSI_CMD. The first
thing on that path, qla_chk_edif_rx_sa_delete_pending(), and the
subsequent handling both evaluate GET_CMD_SP(sp), i.e. sp->u.scmd.cmd.
The srb u union overlays the SCSI command pointer with other command
layouts (bsg_job, iocb_cmd). If firmware delivers an unexpected
STATUS_TYPE IOCB for a non-SCSI handle, sp->u.scmd.cmd can read as a
non-NULL garbage pointer, bypassing the NULL checks in
qla_chk_edif_rx_sa_delete_pending() and at the cp == NULL test, and
leading to a wild pointer dereference.
Reject any SRB whose type is not SRB_SCSI_CMD before entering the fast
path. The outstanding_cmds slot is left untouched so a genuinely
non-SCSI command still completes through its proper handler.
References
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Reject non-SCSI SRB on status IOCB fast path
qla2x00_status_entry() filters out non-TYPE_SRB entries and the
SRB_NVME_CMD, SRB_BIDI_CMD and SRB_TM_CMD types, then falls through to a
SCSI fast path that assumes the command is an SRB_SCSI_CMD. The first
thing on that path, qla_chk_edif_rx_sa_delete_pending(), and the
subsequent handling both evaluate GET_CMD_SP(sp), i.e. sp->u.scmd.cmd.
The srb u union overlays the SCSI command pointer with other command
layouts (bsg_job, iocb_cmd). If firmware delivers an unexpected
STATUS_TYPE IOCB for a non-SCSI handle, sp->u.scmd.cmd can read as a
non-NULL garbage pointer, bypassing the NULL checks in
qla_chk_edif_rx_sa_delete_pending() and at the cp == NULL test, and
leading to a wild pointer dereference.
Reject any SRB whose type is not SRB_SCSI_CMD before entering the fast
path. The outstanding_cmds slot is left untouched so a genuinely
non-SCSI command still completes through its proper handler.
References