diff options
| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2025-03-21 18:49:49 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-07-06 11:01:35 +0200 |
| commit | 53809d38ec3648d0b3532dd46dbf042d2751f479 (patch) | |
| tree | 0f44c6e479ebef2a4b2c218b0c9add85e83e3efe | |
| parent | 4fb6703824793bcdddaf5b4efaa6cba16328878e (diff) | |
usb: Add checks for snprintf() calls in usb_alloc_dev()
[ Upstream commit 82fe5107fa3d21d6c3fba091c9dbc50495588630 ]
When creating a device path in the driver the snprintf() takes
up to 16 characters long argument along with the additional up to
12 characters for the signed integer (as it can't see the actual limits)
and tries to pack this into 16 bytes array. GCC complains about that
when build with `make W=1`:
drivers/usb/core/usb.c:705:25: note: ‘snprintf’ output between 3 and 28 bytes into a destination of size 16
Since everything works until now, let's just check for the potential
buffer overflow and bail out. It is most likely a never happen situation,
but at least it makes GCC happy.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20250321164949.423957-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/usb/core/usb.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 0b4685aad2d5..118fa4c93a79 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -695,15 +695,16 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, device_set_of_node_from_dev(&dev->dev, bus->sysdev); dev_set_name(&dev->dev, "usb%d", bus->busnum); } else { + int n; + /* match any labeling on the hubs; it's one-based */ if (parent->devpath[0] == '0') { - snprintf(dev->devpath, sizeof dev->devpath, - "%d", port1); + n = snprintf(dev->devpath, sizeof(dev->devpath), "%d", port1); /* Root ports are not counted in route string */ dev->route = 0; } else { - snprintf(dev->devpath, sizeof dev->devpath, - "%s.%d", parent->devpath, port1); + n = snprintf(dev->devpath, sizeof(dev->devpath), "%s.%d", + parent->devpath, port1); /* Route string assumes hubs have less than 16 ports */ if (port1 < 15) dev->route = parent->route + @@ -712,6 +713,11 @@ struct usb_device *usb_alloc_dev(struct usb_device *parent, dev->route = parent->route + (15 << ((parent->level - 1)*4)); } + if (n >= sizeof(dev->devpath)) { + usb_put_hcd(bus_to_hcd(bus)); + usb_put_dev(dev); + return NULL; + } dev->dev.parent = &parent->dev; dev_set_name(&dev->dev, "%d-%s", bus->busnum, dev->devpath); |