From: Arun Easi <aeasi@xxxxxxxxxxx> commit e4f8a29deb3ba30e414dfb6b09e3ae3bf6dbe74a upstream. On some platforms, the current logic of relying on finding new packet solely based on signature pattern can lead to driver reading stale packets. Though this is a bug in those platforms, reduce such exposures by limiting reading packets until the IN pointer. Link: https://lore.kernel.org/r/20220826102559.17474-3-njavali@xxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Reviewed-by: Himanshu Madhani <himanshu.madhani@xxxxxxxxxx> Signed-off-by: Arun Easi <aeasi@xxxxxxxxxxx> Signed-off-by: Nilesh Javali <njavali@xxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/qla2xxx/qla_isr.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) --- a/drivers/scsi/qla2xxx/qla_isr.c +++ b/drivers/scsi/qla2xxx/qla_isr.c @@ -3763,7 +3763,8 @@ void qla24xx_process_response_queue(stru struct qla_hw_data *ha = vha->hw; struct purex_entry_24xx *purex_entry; struct purex_item *pure_item; - u16 cur_ring_index; + u16 rsp_in = 0, cur_ring_index; + int is_shadow_hba; if (!ha->flags.fw_started) return; @@ -3773,7 +3774,18 @@ void qla24xx_process_response_queue(stru qla_cpu_update(rsp->qpair, smp_processor_id()); } - while (rsp->ring_ptr->signature != RESPONSE_PROCESSED) { +#define __update_rsp_in(_is_shadow_hba, _rsp, _rsp_in) \ + do { \ + _rsp_in = _is_shadow_hba ? *(_rsp)->in_ptr : \ + rd_reg_dword_relaxed((_rsp)->rsp_q_in); \ + } while (0) + + is_shadow_hba = IS_SHADOW_REG_CAPABLE(ha); + + __update_rsp_in(is_shadow_hba, rsp, rsp_in); + + while (rsp->ring_index != rsp_in && + rsp->ring_ptr->signature != RESPONSE_PROCESSED) { pkt = (struct sts_entry_24xx *)rsp->ring_ptr; cur_ring_index = rsp->ring_index; @@ -3887,6 +3899,7 @@ process_err: } pure_item = qla27xx_copy_fpin_pkt(vha, (void **)&pkt, &rsp); + __update_rsp_in(is_shadow_hba, rsp, rsp_in); if (!pure_item) break; qla24xx_queue_purex_item(vha, pure_item,
