Commit a3157809 authored by Linus Torvalds's avatar Linus Torvalds

Merge branch 'devicetree/merge' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux

Pull devicetree bugfix from Grant Likely:
 "One buffer overflow bug that shouldn't be left around"

* 'devicetree/merge' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux:
  of: Fix overflow bug in string property parsing functions
parents c4c23fb6 a87fa1d8
......@@ -1279,52 +1279,6 @@ int of_property_read_string(struct device_node *np, const char *propname,
}
EXPORT_SYMBOL_GPL(of_property_read_string);
/**
* of_property_read_string_index - Find and read a string from a multiple
* strings property.
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @index: index of the string in the list of strings
* @out_string: pointer to null terminated return string, modified only if
* return value is 0.
*
* Search for a property in a device tree node and retrieve a null
* terminated string value (pointer to data, not a copy) in the list of strings
* contained in that property.
* Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
* property does not have a value, and -EILSEQ if the string is not
* null-terminated within the length of the property data.
*
* The out_string pointer is modified only if a valid string can be decoded.
*/
int of_property_read_string_index(struct device_node *np, const char *propname,
int index, const char **output)
{
struct property *prop = of_find_property(np, propname, NULL);
int i = 0;
size_t l = 0, total = 0;
const char *p;
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (strnlen(prop->value, prop->length) >= prop->length)
return -EILSEQ;
p = prop->value;
for (i = 0; total < prop->length; total += l, p += l) {
l = strlen(p) + 1;
if (i++ == index) {
*output = p;
return 0;
}
}
return -ENODATA;
}
EXPORT_SYMBOL_GPL(of_property_read_string_index);
/**
* of_property_match_string() - Find string in a list and return index
* @np: pointer to node containing string list property
......@@ -1351,7 +1305,7 @@ int of_property_match_string(struct device_node *np, const char *propname,
end = p + prop->length;
for (i = 0; p < end; i++, p += l) {
l = strlen(p) + 1;
l = strnlen(p, end - p) + 1;
if (p + l > end)
return -EILSEQ;
pr_debug("comparing %s with %s\n", string, p);
......@@ -1363,39 +1317,41 @@ int of_property_match_string(struct device_node *np, const char *propname,
EXPORT_SYMBOL_GPL(of_property_match_string);
/**
* of_property_count_strings - Find and return the number of strings from a
* multiple strings property.
* of_property_read_string_util() - Utility helper for parsing string properties
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_strs: output array of string pointers.
* @sz: number of array elements to read.
* @skip: Number of strings to skip over at beginning of list.
*
* Search for a property in a device tree node and retrieve the number of null
* terminated string contain in it. Returns the number of strings on
* success, -EINVAL if the property does not exist, -ENODATA if property
* does not have a value, and -EILSEQ if the string is not null-terminated
* within the length of the property data.
* Don't call this function directly. It is a utility helper for the
* of_property_read_string*() family of functions.
*/
int of_property_count_strings(struct device_node *np, const char *propname)
int of_property_read_string_helper(struct device_node *np, const char *propname,
const char **out_strs, size_t sz, int skip)
{
struct property *prop = of_find_property(np, propname, NULL);
int i = 0;
size_t l = 0, total = 0;
const char *p;
int l = 0, i = 0;
const char *p, *end;
if (!prop)
return -EINVAL;
if (!prop->value)
return -ENODATA;
if (strnlen(prop->value, prop->length) >= prop->length)
return -EILSEQ;
p = prop->value;
end = p + prop->length;
for (i = 0; total < prop->length; total += l, p += l, i++)
l = strlen(p) + 1;
return i;
for (i = 0; p < end && (!out_strs || i < skip + sz); i++, p += l) {
l = strnlen(p, end - p) + 1;
if (p + l > end)
return -EILSEQ;
if (out_strs && i >= skip)
*out_strs++ = p;
}
i -= skip;
return i <= 0 ? -ENODATA : i;
}
EXPORT_SYMBOL_GPL(of_property_count_strings);
EXPORT_SYMBOL_GPL(of_property_read_string_helper);
void of_print_phandle_args(const char *msg, const struct of_phandle_args *args)
{
......
......@@ -339,8 +339,9 @@ static void __init of_selftest_parse_phandle_with_args(void)
selftest(rc == -EINVAL, "expected:%i got:%i\n", -EINVAL, rc);
}
static void __init of_selftest_property_match_string(void)
static void __init of_selftest_property_string(void)
{
const char *strings[4];
struct device_node *np;
int rc;
......@@ -357,13 +358,66 @@ static void __init of_selftest_property_match_string(void)
rc = of_property_match_string(np, "phandle-list-names", "third");
selftest(rc == 2, "third expected:0 got:%i\n", rc);
rc = of_property_match_string(np, "phandle-list-names", "fourth");
selftest(rc == -ENODATA, "unmatched string; rc=%i", rc);
selftest(rc == -ENODATA, "unmatched string; rc=%i\n", rc);
rc = of_property_match_string(np, "missing-property", "blah");
selftest(rc == -EINVAL, "missing property; rc=%i", rc);
selftest(rc == -EINVAL, "missing property; rc=%i\n", rc);
rc = of_property_match_string(np, "empty-property", "blah");
selftest(rc == -ENODATA, "empty property; rc=%i", rc);
selftest(rc == -ENODATA, "empty property; rc=%i\n", rc);
rc = of_property_match_string(np, "unterminated-string", "blah");
selftest(rc == -EILSEQ, "unterminated string; rc=%i", rc);
selftest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
/* of_property_count_strings() tests */
rc = of_property_count_strings(np, "string-property");
selftest(rc == 1, "Incorrect string count; rc=%i\n", rc);
rc = of_property_count_strings(np, "phandle-list-names");
selftest(rc == 3, "Incorrect string count; rc=%i\n", rc);
rc = of_property_count_strings(np, "unterminated-string");
selftest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
rc = of_property_count_strings(np, "unterminated-string-list");
selftest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc);
/* of_property_read_string_index() tests */
rc = of_property_read_string_index(np, "string-property", 0, strings);
selftest(rc == 0 && !strcmp(strings[0], "foobar"), "of_property_read_string_index() failure; rc=%i\n", rc);
strings[0] = NULL;
rc = of_property_read_string_index(np, "string-property", 1, strings);
selftest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
rc = of_property_read_string_index(np, "phandle-list-names", 0, strings);
selftest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc);
rc = of_property_read_string_index(np, "phandle-list-names", 1, strings);
selftest(rc == 0 && !strcmp(strings[0], "second"), "of_property_read_string_index() failure; rc=%i\n", rc);
rc = of_property_read_string_index(np, "phandle-list-names", 2, strings);
selftest(rc == 0 && !strcmp(strings[0], "third"), "of_property_read_string_index() failure; rc=%i\n", rc);
strings[0] = NULL;
rc = of_property_read_string_index(np, "phandle-list-names", 3, strings);
selftest(rc == -ENODATA && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
strings[0] = NULL;
rc = of_property_read_string_index(np, "unterminated-string", 0, strings);
selftest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
rc = of_property_read_string_index(np, "unterminated-string-list", 0, strings);
selftest(rc == 0 && !strcmp(strings[0], "first"), "of_property_read_string_index() failure; rc=%i\n", rc);
strings[0] = NULL;
rc = of_property_read_string_index(np, "unterminated-string-list", 2, strings); /* should fail */
selftest(rc == -EILSEQ && strings[0] == NULL, "of_property_read_string_index() failure; rc=%i\n", rc);
strings[1] = NULL;
/* of_property_read_string_array() tests */
rc = of_property_read_string_array(np, "string-property", strings, 4);
selftest(rc == 1, "Incorrect string count; rc=%i\n", rc);
rc = of_property_read_string_array(np, "phandle-list-names", strings, 4);
selftest(rc == 3, "Incorrect string count; rc=%i\n", rc);
rc = of_property_read_string_array(np, "unterminated-string", strings, 4);
selftest(rc == -EILSEQ, "unterminated string; rc=%i\n", rc);
/* -- An incorrectly formed string should cause a failure */
rc = of_property_read_string_array(np, "unterminated-string-list", strings, 4);
selftest(rc == -EILSEQ, "unterminated string array; rc=%i\n", rc);
/* -- parsing the correctly formed strings should still work: */
strings[2] = NULL;
rc = of_property_read_string_array(np, "unterminated-string-list", strings, 2);
selftest(rc == 2 && strings[2] == NULL, "of_property_read_string_array() failure; rc=%i\n", rc);
strings[1] = NULL;
rc = of_property_read_string_array(np, "phandle-list-names", strings, 1);
selftest(rc == 1 && strings[1] == NULL, "Overwrote end of string array; rc=%i, str='%s'\n", rc, strings[1]);
}
#define propcmp(p1, p2) (((p1)->length == (p2)->length) && \
......@@ -881,7 +935,7 @@ static int __init of_selftest(void)
of_selftest_find_node_by_name();
of_selftest_dynamic();
of_selftest_parse_phandle_with_args();
of_selftest_property_match_string();
of_selftest_property_string();
of_selftest_property_copy();
of_selftest_changeset();
of_selftest_parse_interrupts();
......
......@@ -39,7 +39,9 @@
phandle-list-bad-args = <&provider2 1 0>,
<&provider3 0>;
empty-property;
string-property = "foobar";
unterminated-string = [40 41 42 43];
unterminated-string-list = "first", "second", [40 41 42 43];
};
};
};
......
......@@ -267,14 +267,12 @@ extern int of_property_read_u64(const struct device_node *np,
extern int of_property_read_string(struct device_node *np,
const char *propname,
const char **out_string);
extern int of_property_read_string_index(struct device_node *np,
const char *propname,
int index, const char **output);
extern int of_property_match_string(struct device_node *np,
const char *propname,
const char *string);
extern int of_property_count_strings(struct device_node *np,
const char *propname);
extern int of_property_read_string_helper(struct device_node *np,
const char *propname,
const char **out_strs, size_t sz, int index);
extern int of_device_is_compatible(const struct device_node *device,
const char *);
extern int of_device_is_available(const struct device_node *device);
......@@ -486,15 +484,9 @@ static inline int of_property_read_string(struct device_node *np,
return -ENOSYS;
}
static inline int of_property_read_string_index(struct device_node *np,
const char *propname, int index,
const char **out_string)
{
return -ENOSYS;
}
static inline int of_property_count_strings(struct device_node *np,
const char *propname)
static inline int of_property_read_string_helper(struct device_node *np,
const char *propname,
const char **out_strs, size_t sz, int index)
{
return -ENOSYS;
}
......@@ -667,6 +659,70 @@ static inline int of_property_count_u64_elems(const struct device_node *np,
return of_property_count_elems_of_size(np, propname, sizeof(u64));
}
/**
* of_property_read_string_array() - Read an array of strings from a multiple
* strings property.
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @out_strs: output array of string pointers.
* @sz: number of array elements to read.
*
* Search for a property in a device tree node and retrieve a list of
* terminated string values (pointer to data, not a copy) in that property.
*
* If @out_strs is NULL, the number of strings in the property is returned.
*/
static inline int of_property_read_string_array(struct device_node *np,
const char *propname, const char **out_strs,
size_t sz)
{
return of_property_read_string_helper(np, propname, out_strs, sz, 0);
}
/**
* of_property_count_strings() - Find and return the number of strings from a
* multiple strings property.
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
*
* Search for a property in a device tree node and retrieve the number of null
* terminated string contain in it. Returns the number of strings on
* success, -EINVAL if the property does not exist, -ENODATA if property
* does not have a value, and -EILSEQ if the string is not null-terminated
* within the length of the property data.
*/
static inline int of_property_count_strings(struct device_node *np,
const char *propname)
{
return of_property_read_string_helper(np, propname, NULL, 0, 0);
}
/**
* of_property_read_string_index() - Find and read a string from a multiple
* strings property.
* @np: device node from which the property value is to be read.
* @propname: name of the property to be searched.
* @index: index of the string in the list of strings
* @out_string: pointer to null terminated return string, modified only if
* return value is 0.
*
* Search for a property in a device tree node and retrieve a null
* terminated string value (pointer to data, not a copy) in the list of strings
* contained in that property.
* Returns 0 on success, -EINVAL if the property does not exist, -ENODATA if
* property does not have a value, and -EILSEQ if the string is not
* null-terminated within the length of the property data.
*
* The out_string pointer is modified only if a valid string can be decoded.
*/
static inline int of_property_read_string_index(struct device_node *np,
const char *propname,
int index, const char **output)
{
int rc = of_property_read_string_helper(np, propname, output, 1, index);
return rc < 0 ? rc : 0;
}
/**
* of_property_read_bool - Findfrom a property
* @np: device node from which the property value is to be read.
......
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