/*
 * Helper functions for handling target threads/cpus
 *
 * Copyright (C) 2012, LG Electronics, Namhyung Kim <namhyung.kim@lge.com>
 *
 * Released under the GPL v2.
 */

#include "target.h"
#include "util.h"
#include "debug.h"

#include <pwd.h>
#include <string.h>


enum target_errno target__validate(struct target *target)
{
	enum target_errno ret = TARGET_ERRNO__SUCCESS;

	if (target->pid)
		target->tid = target->pid;

	/* CPU and PID are mutually exclusive */
	if (target->tid && target->cpu_list) {
		target->cpu_list = NULL;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__PID_OVERRIDE_CPU;
	}

	/* UID and PID are mutually exclusive */
	if (target->tid && target->uid_str) {
		target->uid_str = NULL;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__PID_OVERRIDE_UID;
	}

	/* UID and CPU are mutually exclusive */
	if (target->uid_str && target->cpu_list) {
		target->cpu_list = NULL;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__UID_OVERRIDE_CPU;
	}

	/* PID and SYSTEM are mutually exclusive */
	if (target->tid && target->system_wide) {
		target->system_wide = false;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__PID_OVERRIDE_SYSTEM;
	}

	/* UID and SYSTEM are mutually exclusive */
	if (target->uid_str && target->system_wide) {
		target->system_wide = false;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM;
	}

	/* THREAD and SYSTEM/CPU are mutually exclusive */
	if (target->per_thread && (target->system_wide || target->cpu_list)) {
		target->per_thread = false;
		if (ret == TARGET_ERRNO__SUCCESS)
			ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;
	}

	return ret;
}

enum target_errno target__parse_uid(struct target *target)
{
	struct passwd pwd, *result;
	char buf[1024];
	const char *str = target->uid_str;

	target->uid = UINT_MAX;
	if (str == NULL)
		return TARGET_ERRNO__SUCCESS;

	/* Try user name first */
	getpwnam_r(str, &pwd, buf, sizeof(buf), &result);

	if (result == NULL) {
		/*
		 * The user name not found. Maybe it's a UID number.
		 */
		char *endptr;
		int uid = strtol(str, &endptr, 10);

		if (*endptr != '\0')
			return TARGET_ERRNO__INVALID_UID;

		getpwuid_r(uid, &pwd, buf, sizeof(buf), &result);

		if (result == NULL)
			return TARGET_ERRNO__USER_NOT_FOUND;
	}

	target->uid = result->pw_uid;
	return TARGET_ERRNO__SUCCESS;
}

/*
 * This must have a same ordering as the enum target_errno.
 */
static const char *target__error_str[] = {
	"PID/TID switch overriding CPU",
	"PID/TID switch overriding UID",
	"UID switch overriding CPU",
	"PID/TID switch overriding SYSTEM",
	"UID switch overriding SYSTEM",
	"SYSTEM/CPU switch overriding PER-THREAD",
	"Invalid User: %s",
	"Problems obtaining information for user %s",
};

int target__strerror(struct target *target, int errnum,
			  char *buf, size_t buflen)
{
	int idx;
	const char *msg;

	BUG_ON(buflen == 0);

	if (errnum >= 0) {
		str_error_r(errnum, buf, buflen);
		return 0;
	}

	if (errnum <  __TARGET_ERRNO__START || errnum >= __TARGET_ERRNO__END)
		return -1;

	idx = errnum - __TARGET_ERRNO__START;
	msg = target__error_str[idx];

	switch (errnum) {
	case TARGET_ERRNO__PID_OVERRIDE_CPU ...
	     TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD:
		snprintf(buf, buflen, "%s", msg);
		break;

	case TARGET_ERRNO__INVALID_UID:
	case TARGET_ERRNO__USER_NOT_FOUND:
		snprintf(buf, buflen, msg, target->uid_str);
		break;

	default:
		/* cannot reach here */
		break;
	}

	return 0;
}
/option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Jiri Kosina &lt;jkosina@suse.cz&gt;</td><td class='right'>2017-01-27 22:25:52 +0000</td></tr>
<tr><th>committer</th><td>Ingo Molnar &lt;mingo@kernel.org&gt;</td><td class='right'>2017-01-28 09:18:56 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/fs/adfs?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>bf29bddf0417a4783da3b24e8c9e017ac649326f</a> (<a href='/cgit.cgi/linux/net-next.git/patch/fs/adfs?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>54a05a4883b73f80e4e1d8c4b15750aa01c39932</a> /<a href='/cgit.cgi/linux/net-next.git/tree/fs/adfs?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>fs/adfs</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/fs/adfs?id=883af14e67e8b8702b5560aa64c888c0cd0bd66c'>883af14e67e8b8702b5560aa64c888c0cd0bd66c</a> (<a href='/cgit.cgi/linux/net-next.git/diff/fs/adfs?id=bf29bddf0417a4783da3b24e8c9e017ac649326f&amp;id2=883af14e67e8b8702b5560aa64c888c0cd0bd66c'>diff</a>)</td></tr></table>
<div class='commit-subject'>x86/efi: Always map the first physical page into the EFI pagetables</div><div class='commit-msg'>Commit:

  129766708 ("x86/efi: Only map RAM into EFI page tables if in mixed-mode")

stopped creating 1:1 mappings for all RAM, when running in native 64-bit mode.

It turns out though that there are 64-bit EFI implementations in the wild
(this particular problem has been reported on a Lenovo Yoga 710-11IKB),
which still make use of the first physical page for their own private use,
even though they explicitly mark it EFI_CONVENTIONAL_MEMORY in the memory
map.

In case there is no mapping for this particular frame in the EFI pagetables,
as soon as firmware tries to make use of it, a triple fault occurs and the
system reboots (in case of the Yoga 710-11IKB this is very early during bootup).

Fix that by always mapping the first page of physical memory into the EFI
pagetables. We're free to hand this page to the BIOS, as trim_bios_range()
will reserve the first page and isolate it away from memory allocators anyway.

Note that just reverting 129766708 alone is not enough on v4.9-rc1+ to fix the
regression on affected hardware, as this commit:

   ab72a27da ("x86/efi: Consolidate region mapping logic")

later made the first physical frame not to be mapped anyway.

Reported-by: Hanka Pavlikova &lt;hanka@ucw.cz&gt;
Signed-off-by: Jiri Kosina &lt;jkosina@suse.cz&gt;
Signed-off-by: Matt Fleming &lt;matt@codeblueprint.co.uk&gt;
Cc: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Laura Abbott &lt;labbott@redhat.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vojtech Pavlik &lt;vojtech@ucw.cz&gt;
Cc: Waiman Long &lt;waiman.long@hpe.com&gt;
Cc: linux-efi@vger.kernel.org
Cc: stable@kernel.org # v4.8+
Fixes: 129766708 ("x86/efi: Only map RAM into EFI page tables if in mixed-mode")
Link: http://lkml.kernel.org/r/20170127222552.22336-1-matt@codeblueprint.co.uk
[ Tidied up the changelog and the comment. ]
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=bf29bddf0417a4783da3b24e8c9e017ac649326f'>Diffstat</a> (limited to 'fs/adfs')</div><table summary='diffstat' class='diffstat'>