linux/scripts/dtc/dt-extract-compatibles
Nícolas F. R. A. Prado 8f51593cdc dt: dt-extract-compatibles: Don't follow symlinks when walking tree
The iglob function, which we use to find C source files in the kernel
tree, always follows symbolic links. This can cause unintentional
recursions whenever a symbolic link points to a parent directory. A
common scenario is building the kernel with the output set to a
directory inside the kernel tree, which will contain such a symlink.

Instead of using the iglob function, use os.walk to traverse the
directory tree, which by default doesn't follow symbolic links. fnmatch
is then used to match the glob on the filename, as well as ignore hidden
files (which were ignored by default with iglob).

This approach runs just as fast as using iglob.

Fixes: b6acf80735 ("dt: Add a check for undocumented compatible strings in kernel")
Reported-by: Aishwarya TCV <aishwarya.tcv@arm.com>
Closes: https://lore.kernel.org/all/e90cb52f-d55b-d3ba-3933-6cc7b43fcfbc@arm.com
Signed-off-by: "Nícolas F. R. A. Prado" <nfraprado@collabora.com>
Link: https://lore.kernel.org/r/20231107225624.9811-1-nfraprado@collabora.com
Signed-off-by: Rob Herring <robh@kernel.org>
2023-11-09 11:56:39 -06:00

122 lines
3.6 KiB
Python
Executable File

#!/usr/bin/env python3
# SPDX-License-Identifier: GPL-2.0-only
import fnmatch
import os
import re
import argparse
def parse_of_declare_macros(data, include_driver_macros=True):
""" Find all compatible strings in OF_DECLARE() style macros """
compat_list = []
# CPU_METHOD_OF_DECLARE does not have a compatible string
if include_driver_macros:
re_macros = r'(?<!CPU_METHOD_)(IRQCHIP|OF)_(DECLARE|MATCH)(_DRIVER)?\(.*?\)'
else:
re_macros = r'(?<!CPU_METHOD_)(IRQCHIP|OF)_(DECLARE|MATCH)\(.*?\)'
for m in re.finditer(re_macros, data):
try:
compat = re.search(r'"(.*?)"', m[0])[1]
except:
# Fails on compatible strings in #define, so just skip
continue
compat_list += [compat]
return compat_list
def parse_of_device_id(data, match_table_list=None):
""" Find all compatible strings in of_device_id structs """
compat_list = []
for m in re.finditer(r'of_device_id(\s+\S+)?\s+(\S+)\[\](\s+\S+)?\s*=\s*({.*?);', data):
if match_table_list is not None and m[2] not in match_table_list:
continue
compat_list += re.findall(r'\.compatible\s+=\s+"(\S+)"', m[4])
return compat_list
def parse_of_match_table(data):
""" Find all driver's of_match_table """
match_table_list = []
for m in re.finditer(r'\.of_match_table\s+=\s+(of_match_ptr\()?([a-zA-Z0-9_-]+)', data):
match_table_list.append(m[2])
return match_table_list
def parse_compatibles(file, compat_ignore_list):
with open(file, 'r', encoding='utf-8') as f:
data = f.read().replace('\n', '')
if compat_ignore_list is not None:
# For a compatible in the DT to be matched to a driver it needs to show
# up in a driver's of_match_table
match_table_list = parse_of_match_table(data)
compat_list = parse_of_device_id(data, match_table_list)
compat_list = [compat for compat in compat_list if compat not in compat_ignore_list]
else:
compat_list = parse_of_declare_macros(data)
compat_list += parse_of_device_id(data)
return compat_list
def parse_compatibles_to_ignore(file):
with open(file, 'r', encoding='utf-8') as f:
data = f.read().replace('\n', '')
# Compatibles that show up in OF_DECLARE macros can't be expected to
# match a driver, except for the _DRIVER ones.
return parse_of_declare_macros(data, include_driver_macros=False)
def print_compat(filename, compatibles):
if not compatibles:
return
if show_filename:
compat_str = ' '.join(compatibles)
print(filename + ": compatible(s): " + compat_str)
else:
print(*compatibles, sep='\n')
def glob_without_symlinks(root, glob):
for path, dirs, files in os.walk(root):
# Ignore hidden directories
for d in dirs:
if fnmatch.fnmatch(d, ".*"):
dirs.remove(d)
for f in files:
if fnmatch.fnmatch(f, glob):
yield os.path.join(path, f)
def files_to_parse(path_args):
for f in path_args:
if os.path.isdir(f):
for filename in glob_without_symlinks(f, "*.c"):
yield filename
else:
yield f
show_filename = False
if __name__ == "__main__":
ap = argparse.ArgumentParser()
ap.add_argument("cfile", type=str, nargs='*', help="C source files or directories to parse")
ap.add_argument('-H', '--with-filename', help="Print filename with compatibles", action="store_true")
ap.add_argument('-d', '--driver-match', help="Only print compatibles that should match to a driver", action="store_true")
args = ap.parse_args()
show_filename = args.with_filename
compat_ignore_list = None
if args.driver_match:
compat_ignore_list = []
for f in files_to_parse(args.cfile):
compat_ignore_list.extend(parse_compatibles_to_ignore(f))
for f in files_to_parse(args.cfile):
compat_list = parse_compatibles(f, compat_ignore_list)
print_compat(f, compat_list)