From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm2-f12.google.com (mail-wm2-f12.google.com [74.125.225.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C298A4F7999 for ; Fri, 18 Sep 2026 13:18:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.225.140 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789737524; cv=none; b=uNDKC0Wqu8rgDov+fnaD3cb9dWUPOti5cdCRjUXQP6HadgyOFV6CABULLKR0Jgw3iUnmUEW2Dh++2wR96pxbX3tsPM4VKLHC4WJmsL1t+FIfm0Cu5xtDbH/arUp7AWtXTQ5yhN6wsK3TK4RKd8SGu2Pw7avYhtAKJCnvH/qzxk8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789737524; c=relaxed/simple; bh=MXMecSS5un1Vw5RPUBhc/MQTR/N1uDtr5TFfUDNnDkc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=pJE9dlkLBEIGswWdXDizW1MsDlUjK9SxWVkbg/8EYvagg5Y2o7vs4i1AawF3ZiznBlgGoqMx5XzF9KtTVey3YfndFKRnOEMRPPzAbh1MHN7P9+PPNrG8xamm/ubRdj29U0u4J6yfTlXatxPg95dlOkom/BANs4havEMdssR1MUE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=SMp35hXi; arc=none smtp.client-ip=74.125.225.140 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="SMp35hXi" Received: by mail-wm2-f12.google.com with SMTP id 5b1f17b1804b1-49b912e4b11so4241045e9.3 for ; Fri, 18 Sep 2026 06:18:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1789737519; x=1790342319; darn=vger.kernel.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=FSYhKatlju631s2mF43cFtG3PZ8R0OZ445m3aP3hlTo=; b=SMp35hXiJaeVNxYiS6HIgTgEB/vqI1gkvKZ56xzpON6sbNsdZriJw+qSAgJ3MRE77i QudT/8aAVob0I/o06oGLP1KdduYUkzMv9TzJgqw+ua2H1ZS5kEbvxdyjmOW0thayeBGN PwXhOg2FqNZaAs/HQTmG6QIi/Ag1ma56Hr3aJ9wVb8vKLo0hj3xKcxqu0C2bcM5UTxRp SvSLsuj2+kyqHPuHW6eX0L3VWcB2kGshWm6ki3LNZ52lb05hZslT/5RKGiKOBlD37BuM s/MhhDs7/Y4hWSd4GC+hWI5iQK8XV5qULBYcnesbbyceJjZ22PsvgQozbJlRflDIDV/M pa4A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1789737519; x=1790342319; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=FSYhKatlju631s2mF43cFtG3PZ8R0OZ445m3aP3hlTo=; b=zyZ0eExqzZ1X2ZJsjhRSbItT49Rh8+kYZTmvmNoQhByCYOJKkwUeos+x35B0qCX+hi Du5m+oDBIHUIynbm7GkTYh29l0I5BWvlkipqXcz13miDmP07a7lPYc3eP58oorMKBg9c QNcLM9R7Rwz1T9iBrsIg4alug6CJx7h52cROgEsotfNFePDbjQyEGoElACf3ClKV76Mc al1ramB0nKyLMBqdyDwejBmFmLkW+dGLJkbKrhahFLGSZ9epKfJFtKes2VAUeurL+apq p51+a0z31F91UITCl+QqG1wFlXkgO0AwFpq9CHGYV3GQZ6VxjZKYK0dlGGUsSYkR46wI BfAA== X-Forwarded-Encrypted: i=1; AKwUvByWjIaiyYeMSG2A+rb+t9cv9iMYiaJz3xPu4RFoVdJVnB3Dz4vR3ZRIxRRCoyt6avwgsp4LKWvIcBWKYGw=@vger.kernel.org X-Gm-Message-State: AFuF++l8nkFIlR0mdukqf8yBK3pSCCFTeTILH3JyBpST70uzUvNSkvDS je5PpqwKVsN5rkIXSq/2KNNFm5MTfhO47B/0G0SWU+wDr6yJqkMcGaMq X-Gm-Gg: AYBFou22eTbqk4M+/lqPv3Uo7uJavxChlUo81ZQOQ+FwnGeQgwXTyNReByvWu1X0HOG FoHoYrDCjIjRuXsshmX7ZBOJryTu8DpU8ZmqKyYPXAzgpgZASMKmSb2V19NWl1gQRJvSG2JZjYb IDc2+C88H5fp/8UBP7eWaIbBAUvEnPsufAfBl5rSOZoXFFNJSxgQHwzMU/KW4ZZXv9Lwlorom9N EYwnwcrmregEAtN86+8TEgs6/Smr30Hr2LYZ+bwAxgYUNnKNb96ugp5WBDSOVhexO4HGPaIsiv/ Ns6axw+g7vVdtDUkGEguX9+xd4SyOr6bXANr3Vr8f00ABWLS4pEEAeJ2flDxn0l2fHPFOYJhfp4 O0Lblu3L49jauFgPii36vsPHIPOiRe0ouRhkQ9n6+Y9HhwAo5ki9b69vhx9104eisFjKMRp6AoE S29kJXJsrXTBQck6wdEmf5HU/fxvqe3LWkpfUpTudlbR0Jqe5xbqgWEVUm8VPy7acLOlpl X-Received: by 2002:a05:600c:548c:b0:49e:6e7c:d895 with SMTP id 5b1f17b1804b1-49fc584fee0mr32705835e9.26.1789737518934; Fri, 18 Sep 2026 06:18:38 -0700 (PDT) Received: from localhost ([2c0f:3d00:6be:8900:ce5e:9212:ea4b:f30]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-4872008fe3csm4156879f8f.37.2026.09.18.06.18.37 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Sep 2026 06:18:38 -0700 (PDT) Date: Fri, 18 Sep 2026 16:18:34 +0300 From: Dan Carpenter To: Ricardo Ribalda Cc: Laurent Pinchart , Hans de Goede , Mauro Carvalho Chehab , Hans Verkuil , Yunke Cao , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] media: uvcvideo: Fix buffer overflow in uvc_mapping_get_menu_value() Message-ID: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Sep 18, 2026 at 02:59:29PM +0200, Ricardo Ribalda wrote: > Hi Dan > > I believe that for all the uses of uvc_mapping_get_menu_value we are > already doing bound checks: > > index >= BITS_PER_TYPE(mapping->menu_mask) in uvc_query_v4l2_menu() > value> fls(mapping->menu_mask) -1 in uvc_ctrl_clamp() > BIT(i) <= mapping->menu_mask in uvc_menu_to_v4l2_menu() > The problematic caller is uvc_set_le_value(). value = *(s32 *)v4l2_in; Smatch thinks that is called from uvc_mapping_set_xctrl_compound(). drivers/media/usb/uvc/uvc_ctrl.c 2772 data = memdup_user(xctrl->ptr, size); 2773 if (IS_ERR(data)) 2774 return PTR_ERR(data); 2775 2776 return mapping->set(mapping, size, data, 2777 uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT)); But maybe that mapping->set can't point to uvc_set_le_value. > In any case, I think this patch is still worthwhile. It will help us > avoiding bugs in the future (have you found this with a new test for > smatch?) > and if we go that way it is probably a good idea to also "fix" > uvc_mapping_get_menu_name() > > > On Fri, 18 Sept 2026 at 14:20, Dan Carpenter wrote: > > > > The "idx" value is a user controlled u32 so we have to bounds check it > > before calling test_bit() to avoid reading beyond the end of the bitmap. > Maybe change the commit message as well to avoid stable cherry picking > it blindly (sorry seems like I am more picky than usual :) ) > I mean if uvc_set_le_value() turns out not to be a bug then, of course. > > > > Fixes: 4e15c535659b ("media: uvcvideo: Support any size for mapping get/set") > I believe this should be: > Fixes: 40140eda661e ("media: uvcvideo: Implement mask for V4L2_CTRL_TYPE_MENU") > or no Fixes at all. > > > > > Signed-off-by: Dan Carpenter > > --- > > drivers/media/usb/uvc/uvc_ctrl.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c > > index 3ca108b83f1d..f157ed99be4e 100644 > > --- a/drivers/media/usb/uvc/uvc_ctrl.c > > +++ b/drivers/media/usb/uvc/uvc_ctrl.c > > @@ -538,7 +538,7 @@ static void uvc_mapping_set_s32(struct uvc_control_mapping *mapping, > > static int uvc_mapping_get_menu_value(const struct uvc_control_mapping *mapping, > > u32 idx) > > { > > - if (!test_bit(idx, &mapping->menu_mask)) > > + if (idx >= BITS_PER_LONG || !test_bit(idx, &mapping->menu_mask)) > > return -EINVAL; > > What about using BITS_PER_TYPE(mapping->menu_mask) to be consistent? > Sure. regards, dan carpenter