[PATCH 5.15.y] scsi: ufs: bsg: Reject UIC commands with a non-zero result byte

[Sasha Levin <sashal@kernel.org>]

From: Stanley Jhu <stanleyjhu@google.com>

[ Upstream commit 1ae42513205a38b811afedb6797f9f9c4de37b90 ]

ufs_bsg_request() passes the user-supplied UIC argument2 unchanged,
including the result byte (bits 7:0) that only the host controller
writes. A non-zero value triggers the WARN_ON_ONCE() in
ufshcd_dispatch_uic_cmd() and corrupts the reported result. Found by
syzkaller.

Reject UIC commands that have the result byte set with -EINVAL.

Fixes: e77044c5a842 ("scsi: ufs-bsg: Add support for uic commands in ufs_bsg_request()")
Fixes: 9fb4c793223b ("scsi: ufs: core: Complain if UIC argument 2 is invalid")
Cc: stable@vger.kernel.org
Signed-off-by: Stanley Jhu <stanleyjhu@google.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://patch.msgid.link/20261015001855.3450573-5-stanleyjhu@google.com
Signed-off-by: Martin K. Petersen (Oracle) <mkp@kernel.org>
[ sashal: adapted the patch to the older UFS source layout under the SCSI subsystem ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/ufs/ufs_bsg.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/scsi/ufs/ufs_bsg.c b/drivers/scsi/ufs/ufs_bsg.c
index b8bbfd81b8ae0..207b220e451dd 100644
--- a/drivers/scsi/ufs/ufs_bsg.c
+++ b/drivers/scsi/ufs/ufs_bsg.c
@@ -123,6 +123,10 @@ static int ufs_bsg_request(struct bsg_job *job)
 		break;
 	case UPIU_TRANSACTION_UIC_CMD:
 		memcpy(&uc, &bsg_request->upiu_req.uc, UIC_CMD_SIZE);
+		if (uc.argument2 & MASK_UIC_COMMAND_RESULT) {
+			ret = -EINVAL;
+			break;
+		}
 		ret = ufshcd_send_uic_cmd(hba, &uc);
 		if (ret)
 			dev_err(hba->dev,
-- 
2.53.0