diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/rfkill/core.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/net/rfkill/core.c b/net/rfkill/core.c index 79693fe2001..47497c97c8d 100644 --- a/net/rfkill/core.c +++ b/net/rfkill/core.c @@ -1076,10 +1076,16 @@ static ssize_t rfkill_fop_write(struct file *file, const char __user *buf, struct rfkill_event ev; /* we don't need the 'hard' variable but accept it */ - if (count < sizeof(ev) - 1) + if (count < RFKILL_EVENT_SIZE_V1 - 1) return -EINVAL; - if (copy_from_user(&ev, buf, sizeof(ev) - 1)) + /* + * Copy as much data as we can accept into our 'ev' buffer, + * but tell userspace how much we've copied so it can determine + * our API version even in a write() call, if it cares. + */ + count = min(count, sizeof(ev)); + if (copy_from_user(&ev, buf, count)) return -EFAULT; if (ev.op != RFKILL_OP_CHANGE && ev.op != RFKILL_OP_CHANGE_ALL) |