[PATCH 4.19 20/58] scsi: mptscsih: Fix read sense data size

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Tomas Henzl <thenzl@redhat.com>

[ Upstream commit afe89f115e84edbc76d316759e206580a06c6973 ]

The sense data buffer in sense_buf_pool is allocated with size of
MPT_SENSE_BUFFER_ALLOC(64) (multiplied by req_depth) while SNS_LEN(sc)(96)
is used when reading the data.  That may lead to a read from unallocated
area, sometimes from another (unallocated) page.  To fix this, limit the
read size to MPT_SENSE_BUFFER_ALLOC.

Link: https://lore.kernel.org/r/20200616150446.4840-1-thenzl@redhat.com
Co-developed-by: Stanislav Saner <ssaner@redhat.com>
Signed-off-by: Stanislav Saner <ssaner@redhat.com>
Signed-off-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/message/fusion/mptscsih.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/message/fusion/mptscsih.c b/drivers/message/fusion/mptscsih.c
index 6ba07c7feb92b..2af7ae13449d3 100644
--- a/drivers/message/fusion/mptscsih.c
+++ b/drivers/message/fusion/mptscsih.c
@@ -118,8 +118,6 @@ int 		mptscsih_suspend(struct pci_dev *pdev, pm_message_t state);
 int 		mptscsih_resume(struct pci_dev *pdev);
 #endif
 
-#define SNS_LEN(scp)	SCSI_SENSE_BUFFERSIZE
-
 
 /*=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/
 /*
@@ -2420,7 +2418,7 @@ mptscsih_copy_sense_data(struct scsi_cmnd *sc, MPT_SCSI_HOST *hd, MPT_FRAME_HDR
 		/* Copy the sense received into the scsi command block. */
 		req_index = le16_to_cpu(mf->u.frame.hwhdr.msgctxu.fld.req_idx);
 		sense_data = ((u8 *)ioc->sense_buf_pool + (req_index * MPT_SENSE_BUFFER_ALLOC));
-		memcpy(sc->sense_buffer, sense_data, SNS_LEN(sc));
+		memcpy(sc->sense_buffer, sense_data, MPT_SENSE_BUFFER_ALLOC);
 
 		/* Log SMART data (asc = 0x5D, non-IM case only) if required.
 		 */
-- 
2.25.1