[PATCH 13/13] Re-enable and clean up "check_config()" in headers_check.pl
From: Palmer Dabbelt <palmer@dabbelt.com>
Date: 2015-11-03 19:46:34
Also in:
kexec, linux-api, linux-fsdevel, lkml
Subsystem:
the rest · Maintainer:
Linus Torvalds
I recently got bit by a CONFIG_ in userspace bug. This has apparently happened before, but the check got disabled for triggering too much. In order to reduce false positives, I added some hueristics to avoid detecting comments. Since these tests all pass, I've now re-enabled them. Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com> Reviewed-by: Andrew Waterman <redacted> Reviewed-by: Albert Ou <aou@eecs.berkeley.edu> --- scripts/headers_check.pl | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/scripts/headers_check.pl b/scripts/headers_check.pl
index 62320f9..1634b51 100755
--- a/scripts/headers_check.pl
+++ b/scripts/headers_check.pl@@ -27,6 +27,7 @@ my $ret = 0; my $line; my $lineno = 0; my $filename; +my $check_config_in_multiline_comment = 0; foreach my $file (@files) { $filename = $file;
@@ -40,7 +41,7 @@ foreach my $file (@files) { &check_asm_types(); &check_sizetypes(); &check_declarations(); - # Dropped for now. Too much noise &check_config(); + &check_config(); } close $fh; }
@@ -78,7 +79,21 @@ sub check_declarations sub check_config { - if ($line =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) { + my $nocomments = $line; + $nocomments =~ s/\/\*.*\*\///; # Remove ANSI-style comments (/* to */) + $nocomments =~ s/\/\/.*//; # Remove C99-style comments (// to EOL) + + # Check to see if we're within a multiline comment, and if so + # just remove the whole line. I tried matching on '^ * ', but + # there's one header that doesn't prepend multi-line comments + # with * so that won't work. + if ($nocomments =~ m/\/\*/) { $check_config_in_multiline_comment = 1; } + if ($nocomments =~ m/\*\//) { $check_config_in_multiline_comment = 0; } + if ($check_config_in_multiline_comment == 1) { $nocomments = "" } + + # Check to see if there is something that looks like CONFIG_ + # inside a userspace-accessible header file and if so, print that out. + if ($nocomments =~ m/[^a-zA-Z0-9_]+CONFIG_([a-zA-Z0-9_]+)[^a-zA-Z0-9_]/) { printf STDERR "$filename:$lineno: leaks CONFIG_$1 to userspace where it is not valid\n"; } }
--
2.4.10