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 F06FA3570CC; Mon, 2 Feb 2026 09:59:53 +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=1770026394; cv=none; b=gLivVZBPDBoBa3h4BwikgCvDYLXHPkm8TAk+NiSKZDtqElShWlE4Y1gdna7jUcU3I148MwUYVhtFfGNajLV48AiFQeXShTQlKVO2Loh7okDE0UkYg8gcKJ/9JqfSsx5jrKf6jyqalDk+dOubPqhmcUsRS2LkpC9fqeEIDHxAubo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770026394; c=relaxed/simple; bh=TmoHHrqGpHnyUdm3r7UYpmil7JS9bcpmpcteUVJVhlU=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=OW+HosDJNwTb1iPPlMkHTVVwknLyhEv82LqR4DuB+niXaR0TIdCMarLlI5m5CF4U6S3UF/OQjLOevNHGaIU048tTfXwLLXw+IbnzyZlF5bqRr3hEr7UT6iIaCmy4JzJOYVKLiYS6wgf54hIV4ezsngWcYcROwEeineCd95JjA48= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BVwlTeHj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BVwlTeHj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74C46C2BC87; Mon, 2 Feb 2026 09:59:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770026393; bh=TmoHHrqGpHnyUdm3r7UYpmil7JS9bcpmpcteUVJVhlU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BVwlTeHjyRMw/f98dRafO+WxW2pa/VChMQknnYrwRrBoESK1uYOq95icigvzwSlwX Lob6jtX48avGe+fkSVTSL1sIV1YpmDeyg/7FsKPD2hGZNA2+GaHzZcCXaiao6Bd1Lp wstfrGk86S/LkLBIEmLDayFpbjXKdlcTxDA7Xgt53ONDewUeg1SrHB3kkKnAjpNqDo A3JiaEfkK7PSNAtRznkhBFP4cq4dNhzcUWtcTzIyhvBpvez1M2jLEkKzv6TtLOyOTy vIsGuKyKbAt49t7UjQdX1M2/9GW6ZwDNuRBqdB3W6AlayGbFSgjTFZ6xbZsAemQDuo 59fOBxTfTrHNQ== From: Arnd Bergmann To: "Michael S. Tsirkin" , Jason Wang , Xie Yongji Cc: Arnd Bergmann , Xuan Zhuo , =?UTF-8?q?Eugenio=20P=C3=A9rez?= , Anders Roxell , Marco Crivellari , virtualization@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH 2/2] vduse: fix compat handling for VDUSE_IOTLB_GET_FD/VDUSE_VQ_GET_INFO Date: Mon, 2 Feb 2026 10:59:32 +0100 Message-Id: <20260202095940.1358613-2-arnd@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20260202095940.1358613-1-arnd@kernel.org> References: <20260202095940.1358613-1-arnd@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Arnd Bergmann These two ioctls are incompatible on 32-bit x86 userspace, because the data structures are shorter than they are on 64-bit. Add compad handling to the regular ioctl handler to just handle them the same way and ignore the extra padding. This could be done in a separate .compat_ioctl handler, but the main one already handles two versions of VDUSE_IOTLB_GET_FD, so adding a third one fits in rather well. Fixes: ad146355bfad ("vduse: Support querying information of IOVA regions") Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace") Signed-off-by: Arnd Bergmann --- drivers/vdpa/vdpa_user/vduse_dev.c | 43 +++++++++++++++++++++++++++--- 1 file changed, 40 insertions(+), 3 deletions(-) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index 405d59610f76..39cbff2f379d 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1341,6 +1341,37 @@ static int vduse_dev_iotlb_entry(struct vduse_dev *dev, return r; } +#if defined(CONFIG_X86_64) && defined(CONFIG_COMPAT) +/* + * i386 has different alignment constraints than x86_64, + * so there are only 3 bytes of padding instead of 7. + */ +struct compat_vduse_iotlb_entry { + compat_u64 offset; + compat_u64 start; + compat_u64 last; + __u8 perm; + __u8 padding[__alignof__(compat_u64) - 1]; +}; +#define COMPAT_VDUSE_IOTLB_GET_FD _IOWR(VDUSE_BASE, 0x10, struct compat_vduse_iotlb_entry) + +struct compat_vduse_vq_info { + __u32 index; + __u32 num; + compat_u64 desc_addr; + compat_u64 driver_addr; + compat_u64 device_addr; + union { + struct vduse_vq_state_split split; + struct vduse_vq_state_packed packed; + }; + __u8 ready; + __u8 padding[__alignof__(compat_u64) - 1]; +} __uapi_arch_align; +#define COMPAT_VDUSE_VQ_GET_INFO _IOWR(VDUSE_BASE, 0x15, struct compat_vduse_vq_info) + +#endif + static long vduse_dev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -1352,6 +1383,9 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, return -EPERM; switch (cmd) { +#if defined(CONFIG_X86_64) && defined(CONFIG_COMPAT) + case COMPAT_VDUSE_IOTLB_GET_FD: +#endif case VDUSE_IOTLB_GET_FD: case VDUSE_IOTLB_GET_FD2: { struct vduse_iotlb_entry_v2 entry = {0}; @@ -1455,13 +1489,16 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, ret = 0; break; } +#if defined(CONFIG_X86_64) && defined(CONFIG_COMPAT) + case COMPAT_VDUSE_VQ_GET_INFO: +#endif case VDUSE_VQ_GET_INFO: { - struct vduse_vq_info vq_info; + struct vduse_vq_info vq_info = {}; struct vduse_virtqueue *vq; u32 index; ret = -EFAULT; - if (copy_from_user(&vq_info, argp, sizeof(vq_info))) + if (copy_from_user(&vq_info, argp, _IOC_SIZE(cmd))) break; ret = -EINVAL; @@ -1491,7 +1528,7 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, vq_info.ready = vq->ready; ret = -EFAULT; - if (copy_to_user(argp, &vq_info, sizeof(vq_info))) + if (copy_to_user(argp, &vq_info, _IOC_SIZE(cmd))) break; ret = 0; -- 2.39.5