Bug 14237
| Summary: | dvision of signed and unsigned operators usb_stream.c | ||
|---|---|---|---|
| Product: | Drivers | Reporter: | Martin Ettl (ettl.martin) |
| Component: | Sound(OSS) | Assignee: | drivers_sound |
| Status: | CLOSED WILL_NOT_FIX | ||
| Severity: | normal | CC: | alan |
| Priority: | P1 | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Kernel Version: | 2.6.31 | Subsystem: | |
| Regression: | No | Bisected commit-id: | |
Hello, i have checked the linux kernel with the static code analysis tool cppcheck. It brought up an issue in file linux-2.6.31/sound/usb/usx2y/usb_stream.c at line 177. Cppcheck printed the following warning: - dvision of signed and unsigned operators at line 177 Take a look at the code: struct usb_stream *usb_stream_new(struct usb_stream_kernel *sk, struct usb_device *dev, unsigned in_endpoint, unsigned out_endpoint, unsigned sample_rate, unsigned use_packsize, unsigned period_frames, unsigned frame_size) { int packets, max_packsize; int in_pipe, out_pipe; int read_size = sizeof(struct usb_stream); int write_size; int usb_frames = dev->speed == USB_SPEED_HIGH ? 8000 : 1000; int pg; in_pipe = usb_rcvisocpipe(dev, in_endpoint); out_pipe = usb_sndisocpipe(dev, out_endpoint); max_packsize = use_packsize ? use_packsize : usb_maxpacket(dev, in_pipe, 0); /* t_period = period_frames / sample_rate iso_packs = t_period / t_iso_frame = (period_frames / sample_rate) * (1 / t_iso_frame) */ 177 packets = period_frames * usb_frames / sample_rate + 1; .... Indeed, the tool is right, at line 177 there is a division of signed and unsigned operator. This can lead to undifined behaviour! Best regards Martin