[PATCH 5/8] staging: wfx: increase robustness of hif_generic_confirm()
From: Jerome Pouiller
Date: Fri Oct 09 2020 - 13:14:05 EST
From: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
Smatch complains:
drivers/staging/wfx/hif_rx.c:26 hif_generic_confirm() warn: negative user subtract: 0-u16max - 4
20 static int hif_generic_confirm(struct wfx_dev *wdev,
21 const struct hif_msg *hif, const void *buf)
22 {
23 // All confirm messages start with status
24 int status = le32_to_cpup((__le32 *)buf);
25 int cmd = hif->id;
26 int len = le16_to_cpu(hif->len) - 4; // drop header
^^^^^
27
28 WARN(!mutex_is_locked(&wdev->hif_cmd.lock), "data locking error");
In fact, rx_helper() already make the necessary checks on the value of
hif->len. Never mind, add an explicit check to make Smatch happy.
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx>
---
drivers/staging/wfx/hif_rx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/staging/wfx/hif_rx.c b/drivers/staging/wfx/hif_rx.c
index ca09467cba05..2d4265257112 100644
--- a/drivers/staging/wfx/hif_rx.c
+++ b/drivers/staging/wfx/hif_rx.c
@@ -40,10 +40,10 @@ static int hif_generic_confirm(struct wfx_dev *wdev,
}
if (wdev->hif_cmd.buf_recv) {
- if (wdev->hif_cmd.len_recv >= len)
+ if (wdev->hif_cmd.len_recv >= len && len > 0)
memcpy(wdev->hif_cmd.buf_recv, buf, len);
else
- status = -ENOMEM;
+ status = -EIO;
}
wdev->hif_cmd.ret = status;
--
2.28.0