[PATCH 08/17] mpi3mr: Fix out-of-bounds bitmap access during device removal

[Chandrakanth Patil <chandrakanth.patil@broadcom.com>]

Device handles reported by the controller are used to index the remove
pending bitmap and to build a task management request without being
compared against the maximum handle the controller reported.

Check the handle before using it.

Fixes: 13ef29ea4aa0 ("scsi: mpi3mr: Add support for device add/remove event handling")
Signed-off-by: Chandrakanth Patil <chandrakanth.patil@broadcom.com>
---
 drivers/scsi/mpi3mr/mpi3mr_os.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/mpi3mr/mpi3mr_os.c b/drivers/scsi/mpi3mr/mpi3mr_os.c
index 402d1f35d214..15207eed7edc 100644
--- a/drivers/scsi/mpi3mr/mpi3mr_os.c
+++ b/drivers/scsi/mpi3mr/mpi3mr_os.c
@@ -2401,7 +2401,8 @@ static void mpi3mr_dev_rmhs_complete_iou(struct mpi3mr_ioc *mrioc,
 		ioc_info(mrioc,
 		    "%s :dev removal handshake completed successfully: handle(0x%04x)\n",
 		    __func__, drv_cmd->dev_handle);
-		clear_bit(drv_cmd->dev_handle, mrioc->removepend_bitmap);
+		if (drv_cmd->dev_handle < mrioc->facts.max_devhandle)
+			clear_bit(drv_cmd->dev_handle, mrioc->removepend_bitmap);
 	}
 
 	if (!list_empty(&mrioc->delayed_rmhs_list)) {
@@ -2564,6 +2565,12 @@ static void mpi3mr_dev_rmhs_send_tm(struct mpi3mr_ioc *mrioc, u16 handle,
 	drv_cmd->callback = mpi3mr_dev_rmhs_complete_tm;
 	drv_cmd->dev_handle = handle;
 	drv_cmd->iou_rc = iou_rc;
+	if (handle >= mrioc->facts.max_devhandle) {
+		ioc_err(mrioc, "dev_remove_hs: handle(0x%04x) >= max_devhandle(0x%04x)\n",
+			handle, mrioc->facts.max_devhandle);
+		goto out_failed;
+	}
+
 	tm_req.dev_handle = cpu_to_le16(handle);
 	tm_req.task_type = MPI3_SCSITASKMGMT_TASKTYPE_TARGET_RESET;
 	tm_req.host_tag = cpu_to_le16(drv_cmd->host_tag);