scsi: qla2xxx: Fix a Coverity complaint in qla2100_fw_dump()

'cnt' can exceed the size of the risc_ram[] array. Prevent that Coverity
complains by rewriting an address calculation expression. This patch fixes
the following Coverity complaint:

CID 337803 (#1 of 1): Out-of-bounds read (OVERRUN)
109. overrun-local: Overrunning array of 122880 bytes at byte offset 122880
by dereferencing pointer &fw->risc_ram[cnt].

Link: https://lore.kernel.org/r/20200629225454.22863-8-bvanassche@acm.org
Cc: Nilesh Javali <njavali@marvell.com>
Cc: Quinn Tran <qutran@marvell.com>
Cc: Himanshu Madhani <himanshu.madhani@oracle.com>
Cc: Martin Wilck <mwilck@suse.com>
Cc: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/qla2xxx/qla_dbg.c b/drivers/scsi/qla2xxx/qla_dbg.c
index 1900571..41493bd 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_dbg.c
+++ b/drivers/scsi/qla2xxx/qla_dbg.c
@@ -1063,7 +1063,7 @@ qla2100_fw_dump(scsi_qla_host_t *vha)
        }
 
        if (rval == QLA_SUCCESS)
-               qla2xxx_copy_queues(ha, &fw->risc_ram[cnt]);
+               qla2xxx_copy_queues(ha, &fw->queue_dump[0]);
 
        qla2xxx_dump_post_process(base_vha, rval);
 }

diff --git a/drivers/scsi/qla2xxx/qla_dbg.h b/drivers/scsi/qla2xxx/qla_dbg.h
index 54ed020..91eb690 100644 (file)
--- a/drivers/scsi/qla2xxx/qla_dbg.h
+++ b/drivers/scsi/qla2xxx/qla_dbg.h
@@ -53,6 +53,7 @@ struct qla2100_fw_dump {
        __be16 fpm_b0_reg[64];
        __be16 fpm_b1_reg[64];
        __be16 risc_ram[0xf000];
+       u8      queue_dump[];
 };
 
 struct qla24xx_fw_dump {