kernel-ark/arch/powerpc/boot/libfdt/fdt_ro.c
David Gibson 2dccbf4ea0 powerpc: Fix bug in kernel copy of libfdt's fdt_subnode_offset_namelen()
There's currently an off-by-one bug in fdt_subnode_offset_namelen()
which causes it to keep searching after it's finished the subnodes of
the given parent, and into the subnodes of siblings of the original
node which come after it in the tree.  This bug was introduced in
commit ed95d7450d ("powerpc: Update
in-kernel dtc and libfdt to version 1.2.0").

A patch has already been submitted to dtc/libfdt mainline.  We don't
really want to pull in a new upstream version during the 2.6.28 cycle,
but we should still fix this bug, hence this standalone version of the
fix for the in-kernel libfdt.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-10-31 20:14:19 +11:00

470 lines
11 KiB
C

/*
* libfdt - Flat Device Tree manipulation
* Copyright (C) 2006 David Gibson, IBM Corporation.
*
* libfdt is dual licensed: you can use it either under the terms of
* the GPL, or the BSD license, at your option.
*
* a) This library 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 library 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 library; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
* MA 02110-1301 USA
*
* Alternatively,
*
* b) Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
* 2. Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "libfdt_env.h"
#include <fdt.h>
#include <libfdt.h>
#include "libfdt_internal.h"
static int _fdt_nodename_eq(const void *fdt, int offset,
const char *s, int len)
{
const char *p = fdt_offset_ptr(fdt, offset + FDT_TAGSIZE, len+1);
if (! p)
/* short match */
return 0;
if (memcmp(p, s, len) != 0)
return 0;
if (p[len] == '\0')
return 1;
else if (!memchr(s, '@', len) && (p[len] == '@'))
return 1;
else
return 0;
}
const char *fdt_string(const void *fdt, int stroffset)
{
return (const char *)fdt + fdt_off_dt_strings(fdt) + stroffset;
}
int fdt_get_mem_rsv(const void *fdt, int n, uint64_t *address, uint64_t *size)
{
FDT_CHECK_HEADER(fdt);
*address = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->address);
*size = fdt64_to_cpu(_fdt_mem_rsv(fdt, n)->size);
return 0;
}
int fdt_num_mem_rsv(const void *fdt)
{
int i = 0;
while (fdt64_to_cpu(_fdt_mem_rsv(fdt, i)->size) != 0)
i++;
return i;
}
int fdt_subnode_offset_namelen(const void *fdt, int offset,
const char *name, int namelen)
{
int depth;
FDT_CHECK_HEADER(fdt);
for (depth = 0, offset = fdt_next_node(fdt, offset, &depth);
(offset >= 0) && (depth > 0);
offset = fdt_next_node(fdt, offset, &depth)) {
if (depth < 0)
return -FDT_ERR_NOTFOUND;
else if ((depth == 1)
&& _fdt_nodename_eq(fdt, offset, name, namelen))
return offset;
}
if (offset < 0)
return offset; /* error */
else
return -FDT_ERR_NOTFOUND;
}
int fdt_subnode_offset(const void *fdt, int parentoffset,
const char *name)
{
return fdt_subnode_offset_namelen(fdt, parentoffset, name, strlen(name));
}
int fdt_path_offset(const void *fdt, const char *path)
{
const char *end = path + strlen(path);
const char *p = path;
int offset = 0;
FDT_CHECK_HEADER(fdt);
if (*path != '/')
return -FDT_ERR_BADPATH;
while (*p) {
const char *q;
while (*p == '/')
p++;
if (! *p)
return offset;
q = strchr(p, '/');
if (! q)
q = end;
offset = fdt_subnode_offset_namelen(fdt, offset, p, q-p);
if (offset < 0)
return offset;
p = q;
}
return offset;
}
const char *fdt_get_name(const void *fdt, int nodeoffset, int *len)
{
const struct fdt_node_header *nh = _fdt_offset_ptr(fdt, nodeoffset);
int err;
if (((err = fdt_check_header(fdt)) != 0)
|| ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
goto fail;
if (len)
*len = strlen(nh->name);
return nh->name;
fail:
if (len)
*len = err;
return NULL;
}
const struct fdt_property *fdt_get_property(const void *fdt,
int nodeoffset,
const char *name, int *lenp)
{
uint32_t tag;
const struct fdt_property *prop;
int namestroff;
int offset, nextoffset;
int err;
if (((err = fdt_check_header(fdt)) != 0)
|| ((err = _fdt_check_node_offset(fdt, nodeoffset)) < 0))
goto fail;
nextoffset = err;
do {
offset = nextoffset;
tag = fdt_next_tag(fdt, offset, &nextoffset);
switch (tag) {
case FDT_END:
err = -FDT_ERR_TRUNCATED;
goto fail;
case FDT_BEGIN_NODE:
case FDT_END_NODE:
case FDT_NOP:
break;
case FDT_PROP:
err = -FDT_ERR_BADSTRUCTURE;
prop = fdt_offset_ptr(fdt, offset, sizeof(*prop));
if (! prop)
goto fail;
namestroff = fdt32_to_cpu(prop->nameoff);
if (strcmp(fdt_string(fdt, namestroff), name) == 0) {
/* Found it! */
int len = fdt32_to_cpu(prop->len);
prop = fdt_offset_ptr(fdt, offset,
sizeof(*prop)+len);
if (! prop)
goto fail;
if (lenp)
*lenp = len;
return prop;
}
break;
default:
err = -FDT_ERR_BADSTRUCTURE;
goto fail;
}
} while ((tag != FDT_BEGIN_NODE) && (tag != FDT_END_NODE));
err = -FDT_ERR_NOTFOUND;
fail:
if (lenp)
*lenp = err;
return NULL;
}
const void *fdt_getprop(const void *fdt, int nodeoffset,
const char *name, int *lenp)
{
const struct fdt_property *prop;
prop = fdt_get_property(fdt, nodeoffset, name, lenp);
if (! prop)
return NULL;
return prop->data;
}
uint32_t fdt_get_phandle(const void *fdt, int nodeoffset)
{
const uint32_t *php;
int len;
php = fdt_getprop(fdt, nodeoffset, "linux,phandle", &len);
if (!php || (len != sizeof(*php)))
return 0;
return fdt32_to_cpu(*php);
}
int fdt_get_path(const void *fdt, int nodeoffset, char *buf, int buflen)
{
int pdepth = 0, p = 0;
int offset, depth, namelen;
const char *name;
FDT_CHECK_HEADER(fdt);
if (buflen < 2)
return -FDT_ERR_NOSPACE;
for (offset = 0, depth = 0;
(offset >= 0) && (offset <= nodeoffset);
offset = fdt_next_node(fdt, offset, &depth)) {
if (pdepth < depth)
continue; /* overflowed buffer */
while (pdepth > depth) {
do {
p--;
} while (buf[p-1] != '/');
pdepth--;
}
name = fdt_get_name(fdt, offset, &namelen);
if (!name)
return namelen;
if ((p + namelen + 1) <= buflen) {
memcpy(buf + p, name, namelen);
p += namelen;
buf[p++] = '/';
pdepth++;
}
if (offset == nodeoffset) {
if (pdepth < (depth + 1))
return -FDT_ERR_NOSPACE;
if (p > 1) /* special case so that root path is "/", not "" */
p--;
buf[p] = '\0';
return p;
}
}
if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
return -FDT_ERR_BADOFFSET;
else if (offset == -FDT_ERR_BADOFFSET)
return -FDT_ERR_BADSTRUCTURE;
return offset; /* error from fdt_next_node() */
}
int fdt_supernode_atdepth_offset(const void *fdt, int nodeoffset,
int supernodedepth, int *nodedepth)
{
int offset, depth;
int supernodeoffset = -FDT_ERR_INTERNAL;
FDT_CHECK_HEADER(fdt);
if (supernodedepth < 0)
return -FDT_ERR_NOTFOUND;
for (offset = 0, depth = 0;
(offset >= 0) && (offset <= nodeoffset);
offset = fdt_next_node(fdt, offset, &depth)) {
if (depth == supernodedepth)
supernodeoffset = offset;
if (offset == nodeoffset) {
if (nodedepth)
*nodedepth = depth;
if (supernodedepth > depth)
return -FDT_ERR_NOTFOUND;
else
return supernodeoffset;
}
}
if ((offset == -FDT_ERR_NOTFOUND) || (offset >= 0))
return -FDT_ERR_BADOFFSET;
else if (offset == -FDT_ERR_BADOFFSET)
return -FDT_ERR_BADSTRUCTURE;
return offset; /* error from fdt_next_node() */
}
int fdt_node_depth(const void *fdt, int nodeoffset)
{
int nodedepth;
int err;
err = fdt_supernode_atdepth_offset(fdt, nodeoffset, 0, &nodedepth);
if (err)
return (err < 0) ? err : -FDT_ERR_INTERNAL;
return nodedepth;
}
int fdt_parent_offset(const void *fdt, int nodeoffset)
{
int nodedepth = fdt_node_depth(fdt, nodeoffset);
if (nodedepth < 0)
return nodedepth;
return fdt_supernode_atdepth_offset(fdt, nodeoffset,
nodedepth - 1, NULL);
}
int fdt_node_offset_by_prop_value(const void *fdt, int startoffset,
const char *propname,
const void *propval, int proplen)
{
int offset;
const void *val;
int len;
FDT_CHECK_HEADER(fdt);
/* FIXME: The algorithm here is pretty horrible: we scan each
* property of a node in fdt_getprop(), then if that didn't
* find what we want, we scan over them again making our way
* to the next node. Still it's the easiest to implement
* approach; performance can come later. */
for (offset = fdt_next_node(fdt, startoffset, NULL);
offset >= 0;
offset = fdt_next_node(fdt, offset, NULL)) {
val = fdt_getprop(fdt, offset, propname, &len);
if (val && (len == proplen)
&& (memcmp(val, propval, len) == 0))
return offset;
}
return offset; /* error from fdt_next_node() */
}
int fdt_node_offset_by_phandle(const void *fdt, uint32_t phandle)
{
if ((phandle == 0) || (phandle == -1))
return -FDT_ERR_BADPHANDLE;
phandle = cpu_to_fdt32(phandle);
return fdt_node_offset_by_prop_value(fdt, -1, "linux,phandle",
&phandle, sizeof(phandle));
}
int _stringlist_contains(const char *strlist, int listlen, const char *str)
{
int len = strlen(str);
const char *p;
while (listlen >= len) {
if (memcmp(str, strlist, len+1) == 0)
return 1;
p = memchr(strlist, '\0', listlen);
if (!p)
return 0; /* malformed strlist.. */
listlen -= (p-strlist) + 1;
strlist = p + 1;
}
return 0;
}
int fdt_node_check_compatible(const void *fdt, int nodeoffset,
const char *compatible)
{
const void *prop;
int len;
prop = fdt_getprop(fdt, nodeoffset, "compatible", &len);
if (!prop)
return len;
if (_stringlist_contains(prop, len, compatible))
return 0;
else
return 1;
}
int fdt_node_offset_by_compatible(const void *fdt, int startoffset,
const char *compatible)
{
int offset, err;
FDT_CHECK_HEADER(fdt);
/* FIXME: The algorithm here is pretty horrible: we scan each
* property of a node in fdt_node_check_compatible(), then if
* that didn't find what we want, we scan over them again
* making our way to the next node. Still it's the easiest to
* implement approach; performance can come later. */
for (offset = fdt_next_node(fdt, startoffset, NULL);
offset >= 0;
offset = fdt_next_node(fdt, offset, NULL)) {
err = fdt_node_check_compatible(fdt, offset, compatible);
if ((err < 0) && (err != -FDT_ERR_NOTFOUND))
return err;
else if (err == 0)
return offset;
}
return offset; /* error from fdt_next_node() */
}