From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 7BECB18E357; Mon, 28 Oct 2024 06:28:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730096911; cv=none; b=D8rEtxuV/vpq2j8ME9yXcSx50VEf49omtu7GEeJZt8IET0sELT5x+6MB/b4oc0VslfwBEQ8POH4dtKvAlkLYeh1ugLfjH1J15SHAUmRZ5+h9d8iTJojDtAR+tvnCJkJRvmc3NYznYptQ3TUu0Aei8DQp0iWfMr/GKcIxHGfz5cE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730096911; c=relaxed/simple; bh=KFPi8Zmpmjwp692CLvc5tcOIGDDLe1RoKKkd3mQEyUY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=D8wZynlCFxVtEuePAvgAPOgRVnZuVCI9Nql39awJ/g2a0N6sKLJltrPookLAOb2I7rotSq2dW1JLDBFHAva9DaPHFFHrUJSGhCI8e2oh0oD0+jQSEXeA5gUBHxWYIgEooxE4yJqpqj1Q/8Tsyj1K3JRW3VTcgSCcTlmiXkN001g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ExMTBdDd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ExMTBdDd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 145FAC4CEC7; Mon, 28 Oct 2024 06:28:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1730096911; bh=KFPi8Zmpmjwp692CLvc5tcOIGDDLe1RoKKkd3mQEyUY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ExMTBdDd9ZRv/Pgizy2487V2/X5Sw0VjVno41CDTBKdksl+E2HE/17plzBOqr8q5S agSlZ75/EQAZiONNo6GvAxQ/nBhEu8zmYmApw8uyLW1D/45mq9kAGK8eq5SWB5DQRc 4loiDVv27R8vgKo6e+bWeB+E1qyWnCBxg3a8tOKA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Hans de Goede , Jani Nikula , Sasha Levin Subject: [PATCH 5.15 41/80] drm/vboxvideo: Replace fake VLA at end of vbva_mouse_pointer_shape with real VLA Date: Mon, 28 Oct 2024 07:25:21 +0100 Message-ID: <20241028062253.761877036@linuxfoundation.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241028062252.611837461@linuxfoundation.org> References: <20241028062252.611837461@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Hans de Goede [ Upstream commit d92b90f9a54d9300a6e883258e79f36dab53bfae ] Replace the fake VLA at end of the vbva_mouse_pointer_shape shape with a real VLA to fix a "memcpy: detected field-spanning write error" warning: [ 13.319813] memcpy: detected field-spanning write (size 16896) of single field "p->data" at drivers/gpu/drm/vboxvideo/hgsmi_base.c:154 (size 4) [ 13.319841] WARNING: CPU: 0 PID: 1105 at drivers/gpu/drm/vboxvideo/hgsmi_base.c:154 hgsmi_update_pointer_shape+0x192/0x1c0 [vboxvideo] [ 13.320038] Call Trace: [ 13.320173] hgsmi_update_pointer_shape [vboxvideo] [ 13.320184] vbox_cursor_atomic_update [vboxvideo] Note as mentioned in the added comment it seems the original length calculation for the allocated and send hgsmi buffer is 4 bytes too large. Changing this is not the goal of this patch, so this behavior is kept. Signed-off-by: Hans de Goede Reviewed-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20240827104523.17442-1-hdegoede@redhat.com Signed-off-by: Sasha Levin --- drivers/gpu/drm/vboxvideo/hgsmi_base.c | 10 +++++++++- drivers/gpu/drm/vboxvideo/vboxvideo.h | 4 +--- 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/vboxvideo/hgsmi_base.c b/drivers/gpu/drm/vboxvideo/hgsmi_base.c index 8c041d7ce4f1b..87dccaecc3e57 100644 --- a/drivers/gpu/drm/vboxvideo/hgsmi_base.c +++ b/drivers/gpu/drm/vboxvideo/hgsmi_base.c @@ -139,7 +139,15 @@ int hgsmi_update_pointer_shape(struct gen_pool *ctx, u32 flags, flags |= VBOX_MOUSE_POINTER_VISIBLE; } - p = hgsmi_buffer_alloc(ctx, sizeof(*p) + pixel_len, HGSMI_CH_VBVA, + /* + * The 4 extra bytes come from switching struct vbva_mouse_pointer_shape + * from having a 4 bytes fixed array at the end to using a proper VLA + * at the end. These 4 extra bytes were not subtracted from sizeof(*p) + * before the switch to the VLA, so this way the behavior is unchanged. + * Chances are these 4 extra bytes are not necessary but they are kept + * to avoid regressions. + */ + p = hgsmi_buffer_alloc(ctx, sizeof(*p) + pixel_len + 4, HGSMI_CH_VBVA, VBVA_MOUSE_POINTER_SHAPE); if (!p) return -ENOMEM; diff --git a/drivers/gpu/drm/vboxvideo/vboxvideo.h b/drivers/gpu/drm/vboxvideo/vboxvideo.h index a5de40fe1a76a..bed285fe083c8 100644 --- a/drivers/gpu/drm/vboxvideo/vboxvideo.h +++ b/drivers/gpu/drm/vboxvideo/vboxvideo.h @@ -351,10 +351,8 @@ struct vbva_mouse_pointer_shape { * Bytes in the gap between the AND and the XOR mask are undefined. * XOR mask scanlines have no gap between them and size of XOR mask is: * xor_len = width * 4 * height. - * - * Preallocate 4 bytes for accessing actual data as p->data. */ - u8 data[4]; + u8 data[]; } __packed; /* pointer is visible */ -- 2.43.0