From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2DC765A79B; Thu, 16 Jul 2026 16:11:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784218306; cv=none; b=Bo0l0cGCNOBf78TR5AUCD/vWInIE6GwuPRDjLsnJEVv8HYwCzHrRuCHcqqWK6rpKfej1VKeTwPSROYH+dGI5fA9pgKoZoyz8gxKjf99aIIUml1QBFb71+Gxqak52c0M1+KKfS7xz4evFXwX9poKEto2ItHTvYJAZpgk5MePIjrk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784218306; c=relaxed/simple; bh=EeJG6i8FQ9x+3Q+k+4Wemjp63iHAulxRHU2HGhD3XYg=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=PObUaCe8ZHNpKgi5jwrWwIixL4C8hh3xsP9FKnOgOrC2Tzcc9H6n1UmCenvaYK5y0cWfyWitAToE1lfKKvFOWpAeGTXxrM8Oq8LHxM53TTK7v0n+7jfHMJ+Syq2KwME407hL38PCtWH3PnIQDM1e06P/RmSXqhtMf7XlKwHqa70= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=m3nD08oj; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="m3nD08oj" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1784218303; bh=EeJG6i8FQ9x+3Q+k+4Wemjp63iHAulxRHU2HGhD3XYg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=m3nD08ojnKwsVuhEI7u4R3vDJpaOjCA42FKDAx82px7QkjTjEL/viE0rAK1ww1QxI UsvwTQbo7JzBcabWvzCqj52r6SpUw/3g+KdxgzdOu20bqheUJDIGImC7X2HVxFRuaD j8sI+FTsWVi30n1TTVZlw/cu9boLwo6iQOMEyHH/MWsrEOtkIXrVDttI09JlQA9QIk PZQtBmSGHwQRPaSqOUp9hiriT7PcLh34cHZI6WA8bJY7wU2Oj6o18wb7xqBkNJw9lP PXDXFYsBxCRCRj2nsxclfvvcC926QrKIxzLFkCsPipDMwkWvIw5WC5jj/L5DePO63B RcGccIYV/RbMA== Received: from fedora-2.home (unknown [100.64.0.11]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange secp256r1 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id BF17C17E0177; Thu, 16 Jul 2026 18:11:42 +0200 (CEST) Date: Thu, 16 Jul 2026 18:11:37 +0200 From: Boris Brezillon To: Osama Abdelkader Cc: Steven Price , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Heiko Stuebner , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: Re: [PATCH] drm/panthor: reject firmware sections with oversized data Message-ID: <20260716181137.5005eb02@fedora-2.home> In-Reply-To: <20260716143939.21903-1-osama.abdelkader@gmail.com> References: <20260716143939.21903-1-osama.abdelkader@gmail.com> Organization: Collabora X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) 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-Transfer-Encoding: 7bit On Thu, 16 Jul 2026 16:39:38 +0200 Osama Abdelkader wrote: > In panthor_fw_load_section_entry(), the data size to copy is calculated > without validating it against the allocated section_size: > > section->data.size = hdr.data.end - hdr.data.start; > > If a crafted firmware sets data.size larger than the allocated memory, > this could cause a heap buffer overflow in panthor_fw_init_section_mem() > > memcpy(section->mem->kmap, section->data.buf, section->data.size); > > Additionally, if the section->data.size exceeds the BO size, could this > memset underflow the size calculation, leading to a massive out-of-bounds > zeroing of kernel memory? > > memset(section->mem->kmap + section->data.size, 0, > panthor_kernel_bo_size(section->mem) - section->data.size); > > Reject section entries whose initial data is larger than the section size. > > Fixes: 2718d91816ee ("drm/panthor: Add the FW logical block") > Cc: stable@vger.kernel.org > Signed-off-by: Osama Abdelkader Reviewed-by: Boris Brezillon > --- > drivers/gpu/drm/panthor/panthor_fw.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_fw.c b/drivers/gpu/drm/panthor/panthor_fw.c > index 986151681b24..a338c4f0a7f5 100644 > --- a/drivers/gpu/drm/panthor/panthor_fw.c > +++ b/drivers/gpu/drm/panthor/panthor_fw.c > @@ -545,6 +545,7 @@ static int panthor_fw_load_section_entry(struct panthor_device *ptdev, > struct panthor_fw_binary_section_entry_hdr hdr; > struct panthor_fw_section *section; > u32 section_size; > + u32 data_size; > u32 name_len; > int ret; > > @@ -595,6 +596,13 @@ static int panthor_fw_load_section_entry(struct panthor_device *ptdev, > return -EINVAL; > } > > + section_size = hdr.va.end - hdr.va.start; > + data_size = hdr.data.end - hdr.data.start; > + if (data_size > section_size) { > + drm_err(&ptdev->base, "Firmware corrupted, section data exceeds section size\n"); > + return -EINVAL; > + } > + > name_len = iter->size - iter->offset; > > section = drmm_kzalloc(&ptdev->base, sizeof(*section), GFP_KERNEL); > @@ -603,7 +611,7 @@ static int panthor_fw_load_section_entry(struct panthor_device *ptdev, > > list_add_tail(§ion->node, &ptdev->fw->sections); > section->flags = hdr.flags; > - section->data.size = hdr.data.end - hdr.data.start; > + section->data.size = data_size; > > if (section->data.size > 0) { > void *data = drmm_kmalloc(&ptdev->base, section->data.size, GFP_KERNEL); > @@ -626,7 +634,6 @@ static int panthor_fw_load_section_entry(struct panthor_device *ptdev, > section->name = name; > } > > - section_size = hdr.va.end - hdr.va.start; > if (section_size) { > u32 cache_mode = hdr.flags & CSF_FW_BINARY_IFACE_ENTRY_CACHE_MODE_MASK; > struct panthor_gem_object *bo;