From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001
From: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Date: Fri, 4 Sep 2026 10:43:19 +0200
Subject: selftests/bpf: Reject graph kptr use after RCU unlock

Add a sleepable verifier test that loads a graph-node local kptr in an
explicit RCU read-side critical section, then passes its node to
bpf_rbtree_remove() after the section ends.

Before the verifier fix, the stale NON_OWN_REF flag makes the node look like
a live borrowed reference and the program is accepted. After the fix, the
pointer is demoted without NON_OWN_REF and the graph kfunc argument is
rejected.

Also exercise a graph kptr loaded while a spin lock provides implicit RCU
protection. The pointer must be invalidated when the lock is released, which
guards the required ordering between non-owning-reference invalidation and
RCU demotion.

Update the existing fault-protected load test state description. The
post-unlock pointer no longer carries NON_OWN_REF, but remains readable
because the load is rewritten to use BPF_PROBE_MEM.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---
 scripts/checkincludes.pl | 98 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 98 insertions(+)
 create mode 100755 scripts/checkincludes.pl

(limited to 'scripts/checkincludes.pl')

diff --git a/scripts/checkincludes.pl b/scripts/checkincludes.pl
new file mode 100755
index 000000000..b514a956d
--- /dev/null
+++ b/scripts/checkincludes.pl
@@ -0,0 +1,98 @@
+#!/usr/bin/env perl
+# SPDX-License-Identifier: GPL-2.0
+#
+# checkincludes: find/remove files included more than once
+#
+# Copyright abandoned, 2000, Niels Kristian Bech Jensen <nkbj@image.dk>.
+# Copyright 2009 Luis R. Rodriguez <mcgrof@gmail.com>
+#
+# This script checks for duplicate includes. It also has support
+# to remove them in place. Note that this will not take into
+# consideration macros so you should run this only if you know
+# you do have real dups and do not have them under #ifdef's. You
+# could also just review the results.
+
+use strict;
+
+sub usage {
+	print "Usage: checkincludes.pl [-r]\n";
+	print "By default we just warn of duplicates\n";
+	print "To remove duplicated includes in place use -r\n";
+	exit 1;
+}
+
+my $remove = 0;
+
+if ($#ARGV < 0) {
+	usage();
+}
+
+if ($#ARGV >= 1) {
+	if ($ARGV[0] =~ /^-/) {
+		if ($ARGV[0] eq "-r") {
+			$remove = 1;
+			shift;
+		} else {
+			usage();
+		}
+	}
+}
+
+my $dup_counter = 0;
+
+foreach my $file (@ARGV) {
+	open(my $f, '<', $file)
+	    or die "Cannot open $file: $!.\n";
+
+	my %includedfiles = ();
+	my @file_lines = ();
+
+	while (<$f>) {
+		if (m/^\s*#\s*include\s*[<"](\S*)[>"]/o) {
+			++$includedfiles{$1};
+		}
+		push(@file_lines, $_);
+	}
+
+	close($f);
+
+	if (!$remove) {
+		foreach my $filename (keys %includedfiles) {
+			if ($includedfiles{$filename} > 1) {
+				print "$file: $filename is included more than once.\n";
+				++$dup_counter;
+			}
+		}
+		next;
+	}
+
+	open($f, '>', $file)
+	    or die("Cannot write to $file: $!");
+
+	my $dups = 0;
+	foreach (@file_lines) {
+		if (m/^\s*#\s*include\s*[<"](\S*)[>"]/o) {
+			foreach my $filename (keys %includedfiles) {
+				if ($1 eq $filename) {
+					if ($includedfiles{$filename} > 1) {
+						$includedfiles{$filename}--;
+						$dups++;
+						++$dup_counter;
+					} else {
+						print {$f} $_;
+					}
+				}
+			}
+		} else {
+			print {$f} $_;
+		}
+	}
+	if ($dups > 0) {
+		print "$file: removed $dups duplicate includes\n";
+	}
+	close($f);
+}
+
+if ($dup_counter == 0) {
+	print "No duplicate includes found.\n";
+}
-- 
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