| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-ID: <CACT4Y+aZpC8HCq7ztZpV1ahyg2QxGonz6P7bwk+irRT=M2n-YA@mail.gmail.com>
Date: Sun, 30 Oct 2022 07:33:15 -0700
From: Dmitry Vyukov <dvyukov@...gle.com>
To: bongsu.jeon@...sung.com, krzysztof.kozlowski@...aro.org,
netdev@...r.kernel.org
Cc: syzkaller@...glegroups.com
Subject: Re: [PATCH] nfc: Allow to create multiple virtual nci devices
On Sun, 30 Oct 2022 at 07:29, Dmitry Vyukov <dvyukov@...gle.com> wrote:
>
> The current virtual nci driver is great for testing and fuzzing.
> But it allows to create at most one "global" device which does not allow
> to run parallel tests and harms fuzzing isolation and reproducibility.
> Restructure the driver to allow creation of multiple independent devices.
> This should be backwards compatible for existing tests.
>
> Signed-off-by: Dmitry Vyukov <dvyukov@...gle.com>
> Cc: Bongsu Jeon <bongsu.jeon@...sung.com>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
> Cc: netdev@...r.kernel.org
FYI here is this commit on github if it makes it easier to review for you:
https://github.com/dvyukov/linux/commit/d0659d94a8d80f6e33f926b87a37bf1d7bdbb99d
Thanks
> ---
> drivers/nfc/virtual_ncidev.c | 143 ++++++++++++++++-------------------
> 1 file changed, 66 insertions(+), 77 deletions(-)
>
> diff --git a/drivers/nfc/virtual_ncidev.c b/drivers/nfc/virtual_ncidev.c
> index 85c06dbb2c449..8c2836a174ba2 100644
> --- a/drivers/nfc/virtual_ncidev.c
> +++ b/drivers/nfc/virtual_ncidev.c
> @@ -13,12 +13,6 @@
> #include <linux/wait.h>
> #include <net/nfc/nci_core.h>
>
> -enum virtual_ncidev_mode {
> - virtual_ncidev_enabled,
> - virtual_ncidev_disabled,
> - virtual_ncidev_disabling,
> -};
> -
> #define IOCTL_GET_NCIDEV_IDX 0
> #define VIRTUAL_NFC_PROTOCOLS (NFC_PROTO_JEWEL_MASK | \
> NFC_PROTO_MIFARE_MASK | \
> @@ -27,12 +21,12 @@ enum virtual_ncidev_mode {
> NFC_PROTO_ISO14443_B_MASK | \
> NFC_PROTO_ISO15693_MASK)
>
> -static enum virtual_ncidev_mode state;
> -static DECLARE_WAIT_QUEUE_HEAD(wq);
> -static struct miscdevice miscdev;
> -static struct sk_buff *send_buff;
> -static struct nci_dev *ndev;
> -static DEFINE_MUTEX(nci_mutex);
> +struct virtual_nci_dev {
> + struct nci_dev *ndev;
> + struct mutex mtx;
> + struct sk_buff *send_buff;
> + struct wait_queue_head wq;
> +};
>
> static int virtual_nci_open(struct nci_dev *ndev)
> {
> @@ -41,31 +35,29 @@ static int virtual_nci_open(struct nci_dev *ndev)
>
> static int virtual_nci_close(struct nci_dev *ndev)
> {
> - mutex_lock(&nci_mutex);
> - kfree_skb(send_buff);
> - send_buff = NULL;
> - mutex_unlock(&nci_mutex);
> + struct virtual_nci_dev *vdev = nci_get_drvdata(ndev);
> +
> + mutex_lock(&vdev->mtx);
> + kfree_skb(vdev->send_buff);
> + vdev->send_buff = NULL;
> + mutex_unlock(&vdev->mtx);
>
> return 0;
> }
>
> static int virtual_nci_send(struct nci_dev *ndev, struct sk_buff *skb)
> {
> - mutex_lock(&nci_mutex);
> - if (state != virtual_ncidev_enabled) {
> - mutex_unlock(&nci_mutex);
> - kfree_skb(skb);
> - return 0;
> - }
> + struct virtual_nci_dev *vdev = nci_get_drvdata(ndev);
>
> - if (send_buff) {
> - mutex_unlock(&nci_mutex);
> + mutex_lock(&vdev->mtx);
> + if (vdev->send_buff) {
> + mutex_unlock(&vdev->mtx);
> kfree_skb(skb);
> return -1;
> }
> - send_buff = skb_copy(skb, GFP_KERNEL);
> - mutex_unlock(&nci_mutex);
> - wake_up_interruptible(&wq);
> + vdev->send_buff = skb_copy(skb, GFP_KERNEL);
> + mutex_unlock(&vdev->mtx);
> + wake_up_interruptible(&vdev->wq);
> consume_skb(skb);
>
> return 0;
> @@ -80,29 +72,30 @@ static const struct nci_ops virtual_nci_ops = {
> static ssize_t virtual_ncidev_read(struct file *file, char __user *buf,
> size_t count, loff_t *ppos)
> {
> + struct virtual_nci_dev *vdev = file->private_data;
> size_t actual_len;
>
> - mutex_lock(&nci_mutex);
> - while (!send_buff) {
> - mutex_unlock(&nci_mutex);
> - if (wait_event_interruptible(wq, send_buff))
> + mutex_lock(&vdev->mtx);
> + while (!vdev->send_buff) {
> + mutex_unlock(&vdev->mtx);
> + if (wait_event_interruptible(vdev->wq, vdev->send_buff))
> return -EFAULT;
> - mutex_lock(&nci_mutex);
> + mutex_lock(&vdev->mtx);
> }
>
> - actual_len = min_t(size_t, count, send_buff->len);
> + actual_len = min_t(size_t, count, vdev->send_buff->len);
>
> - if (copy_to_user(buf, send_buff->data, actual_len)) {
> - mutex_unlock(&nci_mutex);
> + if (copy_to_user(buf, vdev->send_buff->data, actual_len)) {
> + mutex_unlock(&vdev->mtx);
> return -EFAULT;
> }
>
> - skb_pull(send_buff, actual_len);
> - if (send_buff->len == 0) {
> - consume_skb(send_buff);
> - send_buff = NULL;
> + skb_pull(vdev->send_buff, actual_len);
> + if (vdev->send_buff->len == 0) {
> + consume_skb(vdev->send_buff);
> + vdev->send_buff = NULL;
> }
> - mutex_unlock(&nci_mutex);
> + mutex_unlock(&vdev->mtx);
>
> return actual_len;
> }
> @@ -111,6 +104,7 @@ static ssize_t virtual_ncidev_write(struct file *file,
> const char __user *buf,
> size_t count, loff_t *ppos)
> {
> + struct virtual_nci_dev *vdev = file->private_data;
> struct sk_buff *skb;
>
> skb = alloc_skb(count, GFP_KERNEL);
> @@ -122,63 +116,57 @@ static ssize_t virtual_ncidev_write(struct file *file,
> return -EFAULT;
> }
>
> - nci_recv_frame(ndev, skb);
> + nci_recv_frame(vdev->ndev, skb);
> return count;
> }
>
> static int virtual_ncidev_open(struct inode *inode, struct file *file)
> {
> int ret = 0;
> + struct virtual_nci_dev *vdev;
>
> - mutex_lock(&nci_mutex);
> - if (state != virtual_ncidev_disabled) {
> - mutex_unlock(&nci_mutex);
> - return -EBUSY;
> - }
> -
> - ndev = nci_allocate_device(&virtual_nci_ops, VIRTUAL_NFC_PROTOCOLS,
> - 0, 0);
> - if (!ndev) {
> - mutex_unlock(&nci_mutex);
> + vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
> + if (!vdev)
> + return -ENOMEM;
> + vdev->ndev = nci_allocate_device(&virtual_nci_ops,
> + VIRTUAL_NFC_PROTOCOLS, 0, 0);
> + if (!vdev->ndev) {
> + kfree(vdev);
> return -ENOMEM;
> }
>
> - ret = nci_register_device(ndev);
> + mutex_init(&vdev->mtx);
> + init_waitqueue_head(&vdev->wq);
> + file->private_data = vdev;
> + nci_set_drvdata(vdev->ndev, vdev);
> +
> + ret = nci_register_device(vdev->ndev);
> if (ret < 0) {
> - nci_free_device(ndev);
> - mutex_unlock(&nci_mutex);
> + mutex_destroy(&vdev->mtx);
> + nci_free_device(vdev->ndev);
> + kfree(vdev);
> return ret;
> }
> - state = virtual_ncidev_enabled;
> - mutex_unlock(&nci_mutex);
>
> return 0;
> }
>
> static int virtual_ncidev_close(struct inode *inode, struct file *file)
> {
> - mutex_lock(&nci_mutex);
> -
> - if (state == virtual_ncidev_enabled) {
> - state = virtual_ncidev_disabling;
> - mutex_unlock(&nci_mutex);
> -
> - nci_unregister_device(ndev);
> - nci_free_device(ndev);
> -
> - mutex_lock(&nci_mutex);
> - }
> + struct virtual_nci_dev *vdev = file->private_data;
>
> - state = virtual_ncidev_disabled;
> - mutex_unlock(&nci_mutex);
> + nci_unregister_device(vdev->ndev);
> + nci_free_device(vdev->ndev);
> + mutex_destroy(&vdev->mtx);
>
> return 0;
> }
>
> -static long virtual_ncidev_ioctl(struct file *flip, unsigned int cmd,
> +static long virtual_ncidev_ioctl(struct file *file, unsigned int cmd,
> unsigned long arg)
> {
> - const struct nfc_dev *nfc_dev = ndev->nfc_dev;
> + struct virtual_nci_dev *vdev = file->private_data;
> + const struct nfc_dev *nfc_dev = vdev->ndev->nfc_dev;
> void __user *p = (void __user *)arg;
>
> if (cmd != IOCTL_GET_NCIDEV_IDX)
> @@ -199,14 +187,15 @@ static const struct file_operations virtual_ncidev_fops = {
> .unlocked_ioctl = virtual_ncidev_ioctl
> };
>
> +static struct miscdevice miscdev = {
> + .minor = MISC_DYNAMIC_MINOR,
> + .name = "virtual_nci",
> + .fops = &virtual_ncidev_fops,
> + .mode = 0600,
> +};
> +
> static int __init virtual_ncidev_init(void)
> {
> - state = virtual_ncidev_disabled;
> - miscdev.minor = MISC_DYNAMIC_MINOR;
> - miscdev.name = "virtual_nci";
> - miscdev.fops = &virtual_ncidev_fops;
> - miscdev.mode = 0600;
> -
> return misc_register(&miscdev);
> }
>
>
> base-commit: 02a97e02c64fb3245b84835cbbed1c3a3222e2f1
> --
> 2.38.1.273.g43a17bfeac-goog
>
Powered by blists - more mailing lists