__strncpy_from_user(9)
NAME
__strncpy_from_user - Copy a NUL terminated string from userspace, with
less checking.
SYNOPSIS
long __strncpy_from_user(char * dst, const char __user * src,
long count);
ARGUMENTS
- dst
- Destination address, in kernel space. This buffer must be at least count bytes long.
- src
- Source address, in user space.
- count
- Maximum number of bytes to copy, including the trailing NUL.
DESCRIPTION
Copies a NUL-terminated string from userspace to kernel space. Caller
must check the specified block with access_ok before calling this
function.
On success, returns the length of the string (not including the
trailing NUL).
If access to userspace fails, returns -EFAULT (some data may have been
copied).
If count is smaller than the length of the string, copies count bytes
and returns count.