|
Message-Id: <163a690510e636a23187c0dc9caa09ddac6d4cde.1488228427.git.joe@perches.com> Date: Mon, 27 Feb 2017 12:54:55 -0800 From: Joe Perches <joe@...ches.com> To: Andrew Morton <akpm@...ux-foundation.org>, Andy Whitcroft <apw@...onical.com> Cc: "Roberts, William C" <william.c.roberts@...el.com>, kernel-hardening@...ts.openwall.com, linux-kernel@...r.kernel.org Subject: [PATCH] checkpatch: Add ability to find bad uses of vsprintf %p<foo> extensions %pK was at least once misused at %pk in an out-of-tree module. This lead to some security concerns. Add the ability to track single and multiple line statements for misuses of %p<foo>. Signed-off-by: Joe Perches <joe@...ches.com> --- Andrew, this has gone back and forth a few times. It's imperfect as a patch context with just a single function addition can be missed, but that's not new with $stat tests and just this patch. Perhaps one day the $stat identification mechanism can be improved. Until then, can you please apply this? Thanks. scripts/checkpatch.pl | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index ad5ea5c545b2..9293b8a1c121 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -5676,6 +5676,32 @@ sub process { } } + # check for vsprintf extension %p<foo> misuses + if ($^V && $^V ge 5.10.0 && + defined $stat && + $stat =~ /^\+(?![^\{]*\{\s*).*\b(\w+)\s*\(.*$String\s*,/s && + $1 !~ /^_*volatile_*$/) { + my $bad_extension = ""; + my $lc = $stat =~ tr@\n@@; + $lc = $lc + $linenr; + for (my $count = $linenr; $count <= $lc; $count++) { + my $fmt = get_quoted_string($lines[$count - 1], raw_line($count, 0)); + $fmt =~ s/%%//g; + if ($fmt =~ /(\%[\*\d\.]*p(?![\WFfSsBKRraEhMmIiUDdgVCbGN]).)/) { + $bad_extension = $1; + last; + } + } + if ($bad_extension ne "") { + my $stat_real = raw_line($linenr, 0); + for (my $count = $linenr + 1; $count <= $lc; $count++) { + $stat_real = $stat_real . "\n" . raw_line($count, 0); + } + WARN("VSPRINTF_POINTER_EXTENSION", + "Invalid vsprintf pointer extension '$bad_extension'\n" . "$here\n$stat_real\n"); + } + } + # Check for misused memsets if ($^V && $^V ge 5.10.0 && defined $stat && -- 2.10.0.rc2.1.g053435c
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.