[PATCH v4 1/5] scsi: mpi3mr: fix calculation of valid entry length in alltgt_info

[Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>]

The function mpi3mr_get_all_tgt_info calculates valid entry length in
alltgt_info whose type is pointer to struct mpi3mr_device_map_info.
However, the calculation assumes that the struct would have size of u32.
This results in wrong entry length. Fix the calculation to use the size
of *alltgt_info in place of u32.

Fixes: f5e6d5a34376 ("scsi: mpi3mr: Add support for driver commands")
Cc: stable@vger.kernel.org
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
---
 drivers/scsi/mpi3mr/mpi3mr_app.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/mpi3mr/mpi3mr_app.c b/drivers/scsi/mpi3mr/mpi3mr_app.c
index 9baac224b213..49916ae617e5 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_app.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_app.c
@@ -346,7 +346,8 @@ static long mpi3mr_get_all_tgt_info(struct mpi3mr_ioc *mrioc,
 
 	memcpy(&alltgt_info->num_devices, &num_devices, sizeof(num_devices));
 
-	usr_entrylen = (job->request_payload.payload_len - sizeof(u32)) / sizeof(*devmap_info);
+	usr_entrylen = (job->request_payload.payload_len - sizeof(*alltgt_info))
+		/ sizeof(*devmap_info);
 	usr_entrylen *= sizeof(*devmap_info);
 	min_entrylen = min(usr_entrylen, kern_entrylen);
 	if (min_entrylen && (!memcpy(&alltgt_info->dmi, devmap_info, min_entrylen))) {
-- 
2.38.1