diff options
| author | Lee Jones <lee@kernel.org> | 2023-12-13 16:42:36 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-12-15 13:55:30 +0100 |
| commit | a6eef67cdb84e06112fc29176d6c6061d3ea8d79 (patch) | |
| tree | 70c0c7ea437a6834699f741925039e0f8a5f37af | |
| parent | 01dc7f7c29be8b4fa853eb300f54065d981b31a9 (diff) | |
usb: host: max3421-hcd: Replace snprintf() with the safer scnprintf() variant
There is a general misunderstanding amongst engineers that {v}snprintf()
returns the length of the data *actually* encoded into the destination
array. However, as per the C99 standard {v}snprintf() really returns
the length of the data that *would have been* written if there were
enough space for it. This misunderstanding has led to buffer-overruns
in the past. It's generally considered safer to use the {v}scnprintf()
variants in their place (or even sprintf() in simple cases). So let's
do that.
Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Cristian Birsan <cristian.birsan@microchip.com>
Cc: Nicolas Ferre <nicolas.ferre@microchip.com>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Cc: <linux-arm-kernel@lists.infradead.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20231213164246.1021885-8-lee@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/host/max3421-hcd.c | 18 |
1 files changed, 9 insertions, 9 deletions
diff --git a/drivers/usb/host/max3421-hcd.c b/drivers/usb/host/max3421-hcd.c index d152d72de126..9fe4f48b1898 100644 --- a/drivers/usb/host/max3421-hcd.c +++ b/drivers/usb/host/max3421-hcd.c @@ -1158,12 +1158,12 @@ dump_eps(struct usb_hcd *hcd) end = dp + sizeof(ubuf); *dp = '\0'; list_for_each_entry(urb, &ep->urb_list, urb_list) { - ret = snprintf(dp, end - dp, " %p(%d.%s %d/%d)", urb, - usb_pipetype(urb->pipe), - usb_urb_dir_in(urb) ? "IN" : "OUT", - urb->actual_length, - urb->transfer_buffer_length); - if (ret < 0 || ret >= end - dp) + ret = scnprintf(dp, end - dp, " %p(%d.%s %d/%d)", urb, + usb_pipetype(urb->pipe), + usb_urb_dir_in(urb) ? "IN" : "OUT", + urb->actual_length, + urb->transfer_buffer_length); + if (ret == end - dp - 1) break; /* error or buffer full */ dp += ret; } @@ -1255,9 +1255,9 @@ max3421_handle_irqs(struct usb_hcd *hcd) end = sbuf + sizeof(sbuf); *dp = '\0'; for (i = 0; i < 16; ++i) { - int ret = snprintf(dp, end - dp, " %lu", - max3421_hcd->err_stat[i]); - if (ret < 0 || ret >= end - dp) + int ret = scnprintf(dp, end - dp, " %lu", + max3421_hcd->err_stat[i]); + if (ret == end - dp - 1) break; /* error or buffer full */ dp += ret; } |