From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 DA62D3A5449; Tue, 21 Jul 2026 15:59:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784649595; cv=none; b=aTs14/ufysEloe8+ecE4Or41IFkpT/437DhF7807/YghTjMgAGYpk7CLrN384RgWzHW+no7qYDI8hnwFfjBfHsqjgoij7VgV/hxHdaTIy4uHlgOmymwRJ4pa+4D6jVskmydyIBIfkmumrjP3cbPbCLPTTU8b6u4RPWpshUBoSp0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784649595; c=relaxed/simple; bh=fEZJ4ZZuu8nNPkvkq6DOSd+SS8aZjcW2MQb04C99RG0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=hZXnin0gwuDISwywmLWXHb+O2E+Mnb5KmyGb+Vfx0EgM+SWTYdB2RQpSGD1sXmhl2vvtfa1w/0m9SbqidN4v4pSaHYIxoH+/eBt25PCp/CWnjs4WpQEi8zxJjjOv656DPZLrWNe9v2p1LH4kVYuHuhQBsXaBLEIJWiRq+0HqihE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XQDegt3Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="XQDegt3Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 177BF1F000E9; Tue, 21 Jul 2026 15:59:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784649593; bh=0GfFed5oZeZQNdD/1VsQrZWW3/+bXb21VCLqvcqvMs0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=XQDegt3Z9oNTBKR+7Dcodt3O0kx0iP71hl9OzvHtegXbU6kX84Sehk9CjZpFoCtk8 5MvYXpjYsPD1bYTq/1UwPJqRDxhZvheQqqvnxYaGDcEjP25riBZFEjbP+1QqMjqnFF mx5mipf+2wKzrLScNdSeOUa3N8fufBR/R6bDwIpQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, =?UTF-8?q?Eugenio=20P=C3=A9rez?= , Arnd Bergmann , "Michael S. Tsirkin" , Sasha Levin Subject: [PATCH 7.1 0635/2077] vduse: fix compat handling for VDUSE_IOTLB_GET_FD/VDUSE_VQ_GET_INFO Date: Tue, 21 Jul 2026 17:05:08 +0200 Message-ID: <20260721152607.786353770@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152552.646164743@linuxfoundation.org> References: <20260721152552.646164743@linuxfoundation.org> User-Agent: quilt/0.69 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 7.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Arnd Bergmann [ Upstream commit 455a2a1af92651764e9eb42cec0d95ac142afc28 ] These two ioctls are incompatible on 32-bit x86 userspace, because the data structures are shorter than they are on 64-bit. Add a proper .compat_ioctl handler for x86 that reads the structures with the smaller padding before calling the internal handlers. On all other architectures, CONFIG_COMPAT_FOR_U64_ALIGNMENT is disabled and no special handling is required. Fixes: ad146355bfad ("vduse: Support querying information of IOVA regions") Fixes: c8a6153b6c59 ("vduse: Introduce VDUSE - vDPA Device in Userspace") Acked-by: Eugenio Pérez Signed-off-by: Arnd Bergmann Signed-off-by: Michael S. Tsirkin Message-ID: <20260213154051.4172275-1-arnd@kernel.org> Signed-off-by: Sasha Levin --- drivers/vdpa/vdpa_user/vduse_dev.c | 123 ++++++++++++++++++++++++++++- 1 file changed, 122 insertions(+), 1 deletion(-) diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c index a479fef535ac61..1367d14e5105e6 100644 --- a/drivers/vdpa/vdpa_user/vduse_dev.c +++ b/drivers/vdpa/vdpa_user/vduse_dev.c @@ -1624,6 +1624,127 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd, return ret; } +#ifdef CONFIG_COMPAT_FOR_U64_ALIGNMENT +/* + * 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[3]; +}; +#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[3]; +}; +#define COMPAT_VDUSE_VQ_GET_INFO _IOWR(VDUSE_BASE, 0x15, struct compat_vduse_vq_info) + +static long vduse_dev_compat_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct vduse_dev *dev = file->private_data; + void __user *argp = (void __user *)arg; + int ret; + + if (unlikely(dev->broken)) + return -EPERM; + + switch (cmd) { + case COMPAT_VDUSE_IOTLB_GET_FD: { + struct vduse_iotlb_entry_v2 entry = {0}; + struct file *f = NULL; + + ret = -EFAULT; + if (copy_from_user(&entry, argp, _IOC_SIZE(cmd))) + break; + + ret = vduse_dev_iotlb_entry(dev, &entry, &f, NULL); + if (ret) + break; + + ret = -EINVAL; + if (!f) + break; + + ret = copy_to_user(argp, &entry, _IOC_SIZE(cmd)); + if (ret) { + ret = -EFAULT; + fput(f); + break; + } + ret = receive_fd(f, NULL, perm_to_file_flags(entry.perm)); + fput(f); + break; + } + case COMPAT_VDUSE_VQ_GET_INFO: { + struct vduse_vq_info vq_info = {}; + struct vduse_virtqueue *vq; + u32 index; + + ret = -EFAULT; + if (copy_from_user(&vq_info, argp, + sizeof(struct compat_vduse_vq_info))) + break; + + ret = -EINVAL; + if (vq_info.index >= dev->vq_num) + break; + + index = array_index_nospec(vq_info.index, dev->vq_num); + vq = dev->vqs[index]; + vq_info.desc_addr = vq->desc_addr; + vq_info.driver_addr = vq->driver_addr; + vq_info.device_addr = vq->device_addr; + vq_info.num = vq->num; + + if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) { + vq_info.packed.last_avail_counter = + vq->state.packed.last_avail_counter; + vq_info.packed.last_avail_idx = + vq->state.packed.last_avail_idx; + vq_info.packed.last_used_counter = + vq->state.packed.last_used_counter; + vq_info.packed.last_used_idx = + vq->state.packed.last_used_idx; + } else + vq_info.split.avail_index = + vq->state.split.avail_index; + + vq_info.ready = vq->ready; + + ret = -EFAULT; + if (copy_to_user(argp, &vq_info, + sizeof(struct compat_vduse_vq_info))) + break; + + ret = 0; + break; + } + default: + ret = -ENOIOCTLCMD; + break; + } + + return vduse_dev_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); +} +#else +#define vduse_dev_compat_ioctl compat_ptr_ioctl +#endif + static int vduse_dev_release(struct inode *inode, struct file *file) { struct vduse_dev *dev = file->private_data; @@ -1677,7 +1798,7 @@ static const struct file_operations vduse_dev_fops = { .write_iter = vduse_dev_write_iter, .poll = vduse_dev_poll, .unlocked_ioctl = vduse_dev_ioctl, - .compat_ioctl = compat_ptr_ioctl, + .compat_ioctl = vduse_dev_compat_ioctl, .llseek = noop_llseek, }; -- 2.53.0