table of contents
KERNACC(9) | Kernel Developer's Manual | KERNACC(9) |
NAME¶
kernacc, useracc — check memory regions for accessibilitySYNOPSIS¶
#include <sys/param.h>#include <sys/proc.h>
#include <vm/vm.h>
#include <vm/vm_extern.h> int
kernacc(void *addr, int len, int rw); int
useracc(void *addr, int len, int rw);
DESCRIPTION¶
The kernacc() and useracc() functions check whether operations of the type specified in rw are permitted in the range of virtual addresses given by addr and len. The possible values of rw are any bitwise combination ofVM_PROT_READ
, VM_PROT_WRITE
and VM_PROT_EXECUTE
. kernacc()
checks addresses in the kernel address space, while
useracc() considers addr to represent
an user space address. The process context to use for this operation is taken
from the global variable curproc.
RETURN VALUES¶
Both functions return boolean true if the type of access specified by rw is permitted. Otherwise boolean false is returned.BUGS¶
The process pointer should be passed in as an argument to useracc().June 16, 1996 | Debian |