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// SPDX-License-Identifier: GPL-2.0-only
#include <stdbool.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include "unpriv_helpers.h"
static bool get_mitigations_off(void)
{
char cmdline[4096], *c;
int fd, ret = false;
fd = open("/proc/cmdline", O_RDONLY);
if (fd < 0) {
perror("open /proc/cmdline");
return false;
}
if (read(fd, cmdline, sizeof(cmdline) - 1) < 0) {
perror("read /proc/cmdline");
goto out;
}
cmdline[sizeof(cmdline) - 1] = '\0';
for (c = strtok(cmdline, " \n"); c; c = strtok(NULL, " \n")) {
if (strncmp(c, "mitigations=off", strlen(c)))
continue;
ret = true;
break;
}
out:
close(fd);
return ret;
}
bool get_unpriv_disabled(void)
{
bool disabled;
char buf[2];
FILE *fd;
fd = fopen("/proc/sys/" UNPRIV_SYSCTL, "r");
if (fd) {
disabled = (fgets(buf, 2, fd) == buf && atoi(buf));
fclose(fd);
} else {
perror("fopen /proc/sys/" UNPRIV_SYSCTL);
disabled = true;
}
return disabled ? true : get_mitigations_off();
}
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