From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id Add tests where two packet pointers share an id and tightening one pointer's umax from its var_off would put it less than their constant distance from the other's umax: with an index & 0x38 capped at 50, the base pointer keeps umax 50, so the pointer 8 bytes further on must keep umax 58, even though its known bits allow at most 56. These refused a valid program or accepted an out-of-bounds access before the fix: - check the advanced copy, load through the base: valid, was refused; - check the base, load the byte at base + 1 through a copy advanced by 8: was accepted; - check base + 4, load 4 bytes at base + 2 through base + 8: reads two bytes past the checked range, was accepted; - the same as the second with data_meta pointers checked against data: was accepted. These pass with and without the fix and cover nearby paths: - subtract an unknown scalar from a checked pointer and load below it (the range is kept across a new id); - reach a load through two paths whose checks cover 8 and 7 bytes after the loaded pointer; the second path must not be pruned by the first; - spill a copy of a pointer, check the pointer, fill the copy and load one byte past the checked range: the load is refused, and the copy has the range of the check. Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- scripts/show_delta | 129 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 129 insertions(+) create mode 100755 scripts/show_delta (limited to 'scripts/show_delta') diff --git a/scripts/show_delta b/scripts/show_delta new file mode 100755 index 000000000..3755b6c6e --- /dev/null +++ b/scripts/show_delta @@ -0,0 +1,129 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0-only +# +# show_deltas: Read list of printk messages instrumented with +# time data, and format with time deltas. +# +# Also, you can show the times relative to a fixed point. +# +# Copyright 2003 Sony Corporation +# + +import sys +import string + +def usage(): + print ("""usage: show_delta [] + +This program parses the output from a set of printk message lines which +have time data prefixed because the CONFIG_PRINTK_TIME option is set, or +the kernel command line option "time" is specified. When run with no +options, the time information is converted to show the time delta between +each printk line and the next. When run with the '-b' option, all times +are relative to a single (base) point in time. + +Options: + -h Show this usage help. + -b Specify a base for time references. + can be a number or a string. + If it is a string, the first message line + which matches (at the beginning of the + line) is used as the time reference. + +ex: $ dmesg >timefile + $ show_delta -b NET4 timefile + +will show times relative to the line in the kernel output +starting with "NET4". +""") + sys.exit(1) + +# returns a tuple containing the seconds and text for each message line +# seconds is returned as a float +# raise an exception if no timing data was found +def get_time(line): + if line[0]!="[": + raise ValueError + + # split on closing bracket + (time_str, rest) = string.split(line[1:],']',1) + time = string.atof(time_str) + + #print "time=", time + return (time, rest) + + +# average line looks like: +# [ 0.084282] VFS: Mounted root (romfs filesystem) readonly +# time data is expressed in seconds.useconds, +# convert_line adds a delta for each line +last_time = 0.0 +def convert_line(line, base_time): + global last_time + + try: + (time, rest) = get_time(line) + except: + # if any problem parsing time, don't convert anything + return line + + if base_time: + # show time from base + delta = time - base_time + else: + # just show time from last line + delta = time - last_time + last_time = time + + return ("[%5.6f < %5.6f >]" % (time, delta)) + rest + +def main(): + base_str = "" + filein = "" + for arg in sys.argv[1:]: + if arg=="-b": + base_str = sys.argv[sys.argv.index("-b")+1] + elif arg=="-h": + usage() + else: + filein = arg + + if not filein: + usage() + + try: + lines = open(filein,"r").readlines() + except: + print ("Problem opening file: %s" % filein) + sys.exit(1) + + if base_str: + print ('base= "%s"' % base_str) + # assume a numeric base. If that fails, try searching + # for a matching line. + try: + base_time = float(base_str) + except: + # search for line matching string + found = 0 + for line in lines: + try: + (time, rest) = get_time(line) + except: + continue + if string.find(rest, base_str)==1: + base_time = time + found = 1 + # stop at first match + break + if not found: + print ('Couldn\'t find line matching base pattern "%s"' % base_str) + sys.exit(1) + else: + base_time = 0.0 + + for line in lines: + print (convert_line(line, base_time),) + +if __name__ == "__main__": + main() -- cgit v1.3.1