If streamzap_callback() receives an urb with any non-critical error
status, i.e. any error code other than -ECONNRESET, -ENOENT or -ESHUTDOWN,
it will try to process IR data, ignoring a possible transfer failure.
Make streamzap_callback() process IR data only when urb->status is 0.
Move processing logic to a separate function to make code cleaner and
more similar to the URB completion handlers in other RC drivers.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
Fixes: 19770693c354 ("V4L/DVB: staging/lirc: add lirc_streamzap driver")
Signed-off-by: Murad Masimov <m.masimov@xxxxxxxxxxxxxxxxx>
---
drivers/media/rc/streamzap.c | 68 ++++++++++++++++++++----------------
1 file changed, 38 insertions(+), 30 deletions(-)
diff --git a/drivers/media/rc/streamzap.c b/drivers/media/rc/streamzap.c
index 2ce62fe5d60f..d3b48a0dd1f4 100644
--- a/drivers/media/rc/streamzap.c
+++ b/drivers/media/rc/streamzap.c
@@ -138,39 +138,10 @@ static void sz_push_half_space(struct streamzap_ir *sz,
sz_push_full_space(sz, value & SZ_SPACE_MASK);
}
-/*
- * streamzap_callback - usb IRQ handler callback
- *
- * This procedure is invoked on reception of data from
- * the usb remote.
- */
-static void streamzap_callback(struct urb *urb)
+static void sz_process_ir_data(struct streamzap_ir *sz, int len)
{
- struct streamzap_ir *sz;
unsigned int i;
- int len;
-
- if (!urb)
- return;
-
- sz = urb->context;
- len = urb->actual_length;
-
- switch (urb->status) {
- case -ECONNRESET:
- case -ENOENT:
- case -ESHUTDOWN:
- /*
- * this urb is terminated, clean up.
- * sz might already be invalid at this point
- */
- dev_err(sz->dev, "urb terminated, status: %d\n", urb->status);
- return;
- default:
- break;
- }
- dev_dbg(sz->dev, "%s: received urb, len %d\n", __func__, len);
for (i = 0; i < len; i++) {
dev_dbg(sz->dev, "sz->buf_in[%d]: %x\n",
i, (unsigned char)sz->buf_in[i]);
@@ -219,6 +190,43 @@ static void streamzap_callback(struct urb *urb)
}
ir_raw_event_handle(sz->rdev);
+}
+
+/*
+ * streamzap_callback - usb IRQ handler callback
+ *
+ * This procedure is invoked on reception of data from
+ * the usb remote.
+ */
+static void streamzap_callback(struct urb *urb)
+{
+ struct streamzap_ir *sz;
+ int len;
+
+ if (!urb)
+ return;
+
+ sz = urb->context;
+ len = urb->actual_length;
+
+ switch (urb->status) {
+ case 0:
+ dev_dbg(sz->dev, "%s: received urb, len %d\n", __func__, len);
+ sz_process_ir_data(sz, len);
+ break;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ /*
+ * this urb is terminated, clean up.
+ * sz might already be invalid at this point
+ */
+ dev_err(sz->dev, "urb terminated, status: %d\n", urb->status);
+ return;
+ default:
+ break;
+ }
+
usb_submit_urb(urb, GFP_ATOMIC);
}
--
2.39.2
