3.2.87-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Greg Kroah-Hartman <[email protected]> commit 0994b0a257557e18ee8f0b7c5f0f73fe2b54eec1 upstream. Andrey Konovalov reported that we were not properly checking the upper limit before of a device configuration size before calling memdup_user(), which could cause some problems. So set the upper limit to PAGE_SIZE * 4, which should be good enough for all devices. Reported-by: Andrey Konovalov <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Felipe Balbi <[email protected]> [bwh: Backported to 3.2: adjust filename] Signed-off-by: Ben Hutchings <[email protected]> --- drivers/usb/gadget/inode.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/usb/gadget/inode.c +++ b/drivers/usb/gadget/inode.c @@ -1861,7 +1861,8 @@ dev_config (struct file *fd, const char u32 tag; char *kbuf; - if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) + if ((len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) || + (len > PAGE_SIZE * 4)) return -EINVAL; /* we might need to change message format someday */
