diff options
| -rw-r--r-- | include/uapi/linux/rfkill.h | 14 | ||||
| -rw-r--r-- | net/rfkill/core.c | 48 |
2 files changed, 46 insertions, 16 deletions
diff --git a/include/uapi/linux/rfkill.h b/include/uapi/linux/rfkill.h index 9b77cfc42efa..283c5a7b3f2c 100644 --- a/include/uapi/linux/rfkill.h +++ b/include/uapi/linux/rfkill.h @@ -159,8 +159,16 @@ struct rfkill_event_ext { * old behaviour for all userspace, unless it explicitly opts in to the * rules outlined here by using the new &struct rfkill_event_ext. * - * Userspace using &struct rfkill_event_ext must adhere to the following - * rules + * Additionally, some other userspace (bluez, g-s-d) was reading with a + * large size but as streaming reads rather than message-based, or with + * too strict checks for the returned size. So eventually, we completely + * reverted this, and extended messages need to be opted in to by using + * an ioctl: + * + * ioctl(fd, RFKILL_IOCTL_MAX_SIZE, sizeof(struct rfkill_event_ext)); + * + * Userspace using &struct rfkill_event_ext and the ioctl must adhere to + * the following rules: * * 1. accept short writes, optionally using them to detect that it's * running on an older kernel; @@ -175,6 +183,8 @@ struct rfkill_event_ext { #define RFKILL_IOC_MAGIC 'R' #define RFKILL_IOC_NOINPUT 1 #define RFKILL_IOCTL_NOINPUT _IO(RFKILL_IOC_MAGIC, RFKILL_IOC_NOINPUT) +#define RFKILL_IOC_MAX_SIZE 2 +#define RFKILL_IOCTL_MAX_SIZE _IOW(RFKILL_IOC_MAGIC, RFKILL_IOC_EXT_SIZE, __u32) /* and that's all userspace gets */ diff --git a/net/rfkill/core.c b/net/rfkill/core.c index 5b1927d66f0d..dac4fdc7488a 100644 --- a/net/rfkill/core.c +++ b/net/rfkill/core.c @@ -78,6 +78,7 @@ struct rfkill_data { struct mutex mtx; wait_queue_head_t read_wait; bool input_handler; + u8 max_size; }; @@ -1153,6 +1154,8 @@ static int rfkill_fop_open(struct inode *inode, struct file *file) if (!data) return -ENOMEM; + data->max_size = RFKILL_EVENT_SIZE_V1; + INIT_LIST_HEAD(&data->events); mutex_init(&data->mtx); init_waitqueue_head(&data->read_wait); @@ -1235,6 +1238,7 @@ static ssize_t rfkill_fop_read(struct file *file, char __user *buf, list); sz = min_t(unsigned long, sizeof(ev->ev), count); + sz = min_t(unsigned long, sz, data->max_size); ret = sz; if (copy_to_user(buf, &ev->ev, sz)) ret = -EFAULT; @@ -1249,6 +1253,7 @@ static ssize_t rfkill_fop_read(struct file *file, char __user *buf, static ssize_t rfkill_fop_write(struct file *file, const char __user *buf, size_t count, loff_t *pos) { + struct rfkill_data *data = file->private_data; struct rfkill *rfkill; struct rfkill_event_ext ev; int ret; @@ -1263,6 +1268,7 @@ static ssize_t rfkill_fop_write(struct file *file, const char __user *buf, * our API version even in a write() call, if it cares. */ count = min(count, sizeof(ev)); + count = min_t(size_t, count, data->max_size); if (copy_from_user(&ev, buf, count)) return -EFAULT; @@ -1322,31 +1328,47 @@ static int rfkill_fop_release(struct inode *inode, struct file *file) return 0; } -#ifdef CONFIG_RFKILL_INPUT static long rfkill_fop_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct rfkill_data *data = file->private_data; + int ret = -ENOSYS; + u32 size; if (_IOC_TYPE(cmd) != RFKILL_IOC_MAGIC) return -ENOSYS; - if (_IOC_NR(cmd) != RFKILL_IOC_NOINPUT) - return -ENOSYS; - mutex_lock(&data->mtx); - - if (!data->input_handler) { - if (atomic_inc_return(&rfkill_input_disabled) == 1) - printk(KERN_DEBUG "rfkill: input handler disabled\n"); - data->input_handler = true; + switch (_IOC_NR(cmd)) { +#ifdef CONFIG_RFKILL_INPUT + case RFKILL_IOC_NOINPUT: + if (!data->input_handler) { + if (atomic_inc_return(&rfkill_input_disabled) == 1) + printk(KERN_DEBUG "rfkill: input handler disabled\n"); + data->input_handler = true; + } + ret = 0; + break; +#endif + case RFKILL_IOC_MAX_SIZE: + if (get_user(size, (__u32 __user *)arg)) { + ret = -EFAULT; + break; + } + if (size < RFKILL_EVENT_SIZE_V1 || size > U8_MAX) { + ret = -EINVAL; + break; + } + data->max_size = size; + ret = 0; + break; + default: + break; } - mutex_unlock(&data->mtx); - return 0; + return ret; } -#endif static const struct file_operations rfkill_fops = { .owner = THIS_MODULE, @@ -1355,10 +1377,8 @@ static const struct file_operations rfkill_fops = { .write = rfkill_fop_write, .poll = rfkill_fop_poll, .release = rfkill_fop_release, -#ifdef CONFIG_RFKILL_INPUT .unlocked_ioctl = rfkill_fop_ioctl, .compat_ioctl = compat_ptr_ioctl, -#endif .llseek = no_llseek, }; |