pr_set_mdwe(2const) - BetterMan

pr_set_mdwe(2const)

set the Memory-Deny-Write-Execute protection mask for the calling process

distropkg manpages-dev@6.9.1-1dataset 2026-04-01T06:19:02Z+debian+ec4110e+mandoc:1.14.6-4

Synopsis

#include <linux/prctl.h>
  /* Definition of 
PR_*
 constants */
#include <sys/prctl.h>
int prctl(PR_SET_MDWE, unsigned long 
mask
, 0L, 0L, 0L);

—

Options · 3

PR_MDWE_REFUSE_EXEC_GAIN	New memory mapping protections can't be writable and executable. Non-executable mappings can't become executable.
PR_MDWE_NO_INHERIT (since Linux 6.6)	Do not propagate MDWE protection to child processes on fork(2). Setting this bit requires setting PR_MDWE_REFUSE_EXEC_GAIN too.
EINVAL	mask is not a valid value.

NAME

PR_SET_MDWE - set the Memory-Deny-Write-Execute protection mask for the calling process

Standard C library (libc, -lc)

bash

#include <linux/prctl.h>\n  /* Definition of \nPR_*\n constants */
\n#include <sys/prctl.h>

bash

int prctl(PR_SET_MDWE, unsigned long \nmask\n, 0L, 0L, 0L);

Set the calling process' Memory-Deny-Write-Execute protection mask. Once protection bits are set, they can not be changed.

mask must be a bit mask of:

PR_MDWE_REFUSE_EXEC_GAIN: New memory mapping protections can't be writable and executable. Non-executable mappings can't become executable.
PR_MDWE_NO_INHERIT (since Linux 6.6): Do not propagate MDWE protection to child processes on fork(2). Setting this bit requires setting PR_MDWE_REFUSE_EXEC_GAIN too.

On success, 0 is returned. On error, -1 is returned, and errno is set to indicate the error.

Linux.

Linux 6.3.