kmem(7) 						 Miscellaneous Information Manual						   kmem(7)

NAME

       kmem - perform I/O on kernel memory, based on symbol name

SYNOPSIS


DESCRIPTION

       When used with a valid file descriptor for (kmemfd), can be used to manipulate kernel memory.  The specifics of this manipulation depend on
       the command given as follows:

       Read			mirk_buflen bytes of kernel memory starting at the address for mirk_symname into mirk_buf.  rks is a pointer to  a
				structure, defined below.

       Indirect read.		Read  bytes  of  kernel  memory starting at the address for mirk_symname and use that as the address from which to
				read mirk_buflen bytes of kernel memory into mirk_buf.	rks is a pointer to a structure.

       Write			mirk_buflen bytes from mirk_buf into kernel memory starting at the address for mirk_symname.  rks is a pointer	to
				a structure.

       Indirect write.		Read  bytes  of  kernel  memory starting at the address for mirk_symname and use that as the kernel memory address
				into which mirk_buflen bytes from mirk_buf are written.  rks is a pointer to a structure.

       Increase the hold count by one for the dynamically loaded module whose name is given by
				rks, a pointer to a character string, thereby preventing its unloading.

       Decrease the hold count by one for the dynamically loaded module whose name is given by
				rks, a pointer to a character string.  If the count is thereby reduced to 0, the module becomes  a  candidate  for
				unloading.

       The definition is:

RETURN VALUE

       returns one of the following values:

	      Successful completion.

	      Failure.
		     is set to indicate the error.

ERRORS

       In addition to the values described in ioctl(2), the also sets to one of the following values if the corresponding condition is detected.

       modname	      does not represent a currently loaded module or this is an and the hold count is already 0.

       kmemfd	      open on wrong minor device (i.e., not

       kmemfd	      open for reading and this is an

       symname	      not found.

       modname	      is greater than characters long, or symname is greater that characters long.

SEE ALSO

       getksym(2), ioctl(2), ioctl(5).

																	   kmem(7)