Revision eb35bdd7bca29a13c8ecd44e6fd747a84ce675db authored by Will Deacon on 11 September 2014, 13:38:16 UTC, committed by Will Deacon on 11 September 2014, 17:34:58 UTC
Nathan reports that we leak TLS information from the parent context
during an exec, as we don't clear the TLS registers when flushing the
thread state.

This patch updates the flushing code so that we:

  (1) Unconditionally zero the tpidr_el0 register (since this is fully
      context switched for native tasks and zeroed for compat tasks)

  (2) Zero the tp_value state in thread_info before clearing the
      tpidrr0_el0 register for compat tasks (since this is only writable
      by the set_tls compat syscall and therefore not fully switched).

A missing compiler barrier is also added to the compat set_tls syscall.

Cc: <stable@vger.kernel.org>
Acked-by: Nathan Lynch <Nathan_Lynch@mentor.com>
Reported-by: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
1 parent 3d8afe3
Raw File
treesource.c
/*
 * (C) Copyright David Gibson <dwg@au1.ibm.com>, IBM Corporation.  2005.
 *
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 *                                                                   USA
 */

#include "dtc.h"
#include "srcpos.h"

extern FILE *yyin;
extern int yyparse(void);
extern YYLTYPE yylloc;

struct boot_info *the_boot_info;
int treesource_error;

struct boot_info *dt_from_source(const char *fname)
{
	the_boot_info = NULL;
	treesource_error = 0;

	srcfile_push(fname);
	yyin = current_srcfile->f;
	yylloc.file = current_srcfile;

	if (yyparse() != 0)
		die("Unable to parse input tree\n");

	if (treesource_error)
		die("Syntax error parsing input tree\n");

	return the_boot_info;
}

static void write_prefix(FILE *f, int level)
{
	int i;

	for (i = 0; i < level; i++)
		fputc('\t', f);
}

static int isstring(char c)
{
	return (isprint(c)
		|| (c == '\0')
		|| strchr("\a\b\t\n\v\f\r", c));
}

static void write_propval_string(FILE *f, struct data val)
{
	const char *str = val.val;
	int i;
	struct marker *m = val.markers;

	assert(str[val.len-1] == '\0');

	while (m && (m->offset == 0)) {
		if (m->type == LABEL)
			fprintf(f, "%s: ", m->ref);
		m = m->next;
	}
	fprintf(f, "\"");

	for (i = 0; i < (val.len-1); i++) {
		char c = str[i];

		switch (c) {
		case '\a':
			fprintf(f, "\\a");
			break;
		case '\b':
			fprintf(f, "\\b");
			break;
		case '\t':
			fprintf(f, "\\t");
			break;
		case '\n':
			fprintf(f, "\\n");
			break;
		case '\v':
			fprintf(f, "\\v");
			break;
		case '\f':
			fprintf(f, "\\f");
			break;
		case '\r':
			fprintf(f, "\\r");
			break;
		case '\\':
			fprintf(f, "\\\\");
			break;
		case '\"':
			fprintf(f, "\\\"");
			break;
		case '\0':
			fprintf(f, "\", ");
			while (m && (m->offset < i)) {
				if (m->type == LABEL) {
					assert(m->offset == (i+1));
					fprintf(f, "%s: ", m->ref);
				}
				m = m->next;
			}
			fprintf(f, "\"");
			break;
		default:
			if (isprint(c))
				fprintf(f, "%c", c);
			else
				fprintf(f, "\\x%02hhx", c);
		}
	}
	fprintf(f, "\"");

	/* Wrap up any labels at the end of the value */
	for_each_marker_of_type(m, LABEL) {
		assert (m->offset == val.len);
		fprintf(f, " %s:", m->ref);
	}
}

static void write_propval_cells(FILE *f, struct data val)
{
	void *propend = val.val + val.len;
	cell_t *cp = (cell_t *)val.val;
	struct marker *m = val.markers;

	fprintf(f, "<");
	for (;;) {
		while (m && (m->offset <= ((char *)cp - val.val))) {
			if (m->type == LABEL) {
				assert(m->offset == ((char *)cp - val.val));
				fprintf(f, "%s: ", m->ref);
			}
			m = m->next;
		}

		fprintf(f, "0x%x", fdt32_to_cpu(*cp++));
		if ((void *)cp >= propend)
			break;
		fprintf(f, " ");
	}

	/* Wrap up any labels at the end of the value */
	for_each_marker_of_type(m, LABEL) {
		assert (m->offset == val.len);
		fprintf(f, " %s:", m->ref);
	}
	fprintf(f, ">");
}

static void write_propval_bytes(FILE *f, struct data val)
{
	void *propend = val.val + val.len;
	const char *bp = val.val;
	struct marker *m = val.markers;

	fprintf(f, "[");
	for (;;) {
		while (m && (m->offset == (bp-val.val))) {
			if (m->type == LABEL)
				fprintf(f, "%s: ", m->ref);
			m = m->next;
		}

		fprintf(f, "%02hhx", *bp++);
		if ((const void *)bp >= propend)
			break;
		fprintf(f, " ");
	}

	/* Wrap up any labels at the end of the value */
	for_each_marker_of_type(m, LABEL) {
		assert (m->offset == val.len);
		fprintf(f, " %s:", m->ref);
	}
	fprintf(f, "]");
}

static void write_propval(FILE *f, struct property *prop)
{
	int len = prop->val.len;
	const char *p = prop->val.val;
	struct marker *m = prop->val.markers;
	int nnotstring = 0, nnul = 0;
	int nnotstringlbl = 0, nnotcelllbl = 0;
	int i;

	if (len == 0) {
		fprintf(f, ";\n");
		return;
	}

	for (i = 0; i < len; i++) {
		if (! isstring(p[i]))
			nnotstring++;
		if (p[i] == '\0')
			nnul++;
	}

	for_each_marker_of_type(m, LABEL) {
		if ((m->offset > 0) && (prop->val.val[m->offset - 1] != '\0'))
			nnotstringlbl++;
		if ((m->offset % sizeof(cell_t)) != 0)
			nnotcelllbl++;
	}

	fprintf(f, " = ");
	if ((p[len-1] == '\0') && (nnotstring == 0) && (nnul < (len-nnul))
	    && (nnotstringlbl == 0)) {
		write_propval_string(f, prop->val);
	} else if (((len % sizeof(cell_t)) == 0) && (nnotcelllbl == 0)) {
		write_propval_cells(f, prop->val);
	} else {
		write_propval_bytes(f, prop->val);
	}

	fprintf(f, ";\n");
}

static void write_tree_source_node(FILE *f, struct node *tree, int level)
{
	struct property *prop;
	struct node *child;
	struct label *l;

	write_prefix(f, level);
	for_each_label(tree->labels, l)
		fprintf(f, "%s: ", l->label);
	if (tree->name && (*tree->name))
		fprintf(f, "%s {\n", tree->name);
	else
		fprintf(f, "/ {\n");

	for_each_property(tree, prop) {
		write_prefix(f, level+1);
		for_each_label(prop->labels, l)
			fprintf(f, "%s: ", l->label);
		fprintf(f, "%s", prop->name);
		write_propval(f, prop);
	}
	for_each_child(tree, child) {
		fprintf(f, "\n");
		write_tree_source_node(f, child, level+1);
	}
	write_prefix(f, level);
	fprintf(f, "};\n");
}


void dt_to_source(FILE *f, struct boot_info *bi)
{
	struct reserve_info *re;

	fprintf(f, "/dts-v1/;\n\n");

	for (re = bi->reservelist; re; re = re->next) {
		struct label *l;

		for_each_label(re->labels, l)
			fprintf(f, "%s: ", l->label);
		fprintf(f, "/memreserve/\t0x%016llx 0x%016llx;\n",
			(unsigned long long)re->re.address,
			(unsigned long long)re->re.size);
	}

	write_tree_source_node(f, bi->dt, 0);
}
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