Am Montag, dem 22.09.2025 um 17:16 -0700 schrieb Jakub Kicinski:

On Mon, 22 Sep 2025 12:07:38 +0200 Marc Kleine-Budde wrote:

quoted

+	do {
+		int actual_length;
+		int pos;
+
+		err = usb_bulk_msg(dev->udev,
+				   usb_rcvbulkpipe(dev->udev, 1),
+				   rx_buf,
+				   ESD_USB_RX_BUFFER_SIZE,
+				   &actual_length,
+				   ESD_USB_DRAIN_TIMEOUT_MS);
+		dev_dbg(&dev->udev->dev, "AT %d, LEN %d, ERR %d\n", attempt, actual_length, err);
+		++attempt;
+		if (err)
+			goto bail;
+		if (actual_length == 0)
+			continue;

continue in do-while loops doesn't check the condition.
This looks like a potential infinite loop?

I don't think so. A continue statement in a do, while or for loop
always jumps to the end of the loop body.

See a citation of the C standard there:
https://stackoverflow.com/a/64120354

Therefore there is no potential for an infinite loop due to the continue 
statement.

Refer to following code and its output:

----------------------------------------------
#include <stdio.h>

#define LIMIT   4

int main(void)
{
    int cnt = 0;

    do {
        printf("Top: %d\n", cnt);
        ++cnt;
        if (cnt > 2) continue;
        printf("Bottom: %d\n", cnt);
    } while (printf("Condition: %d\n\n", cnt), cnt < LIMIT);
    
	return 0;
}
----------------------------------------------

Output:
----------------------------------------------
stefanm@pc-stefanm64:~/Tmp$ ./do_continue 
Top: 0
Bottom: 1
Condition: 1

Top: 1
Bottom: 2
Condition: 2

Top: 2
Condition: 3

Top: 3
Condition: 4

----------------------------------------------

Sorry being late with this.

Best regards,
    Stefan