From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <1486757549.2192.20.camel@perches.com> From: Joe Perches Date: Fri, 10 Feb 2017 12:12:29 -0800 In-Reply-To: <1486755469-21573-1-git-send-email-william.c.roberts@intel.com> References: <1486755469-21573-1-git-send-email-william.c.roberts@intel.com> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [kernel-hardening] Re: [PATCH] checkpatch: add warning on %pk instead of %pK usage To: william.c.roberts@intel.com, linux-kernel@vger.kernel.org, apw@canonical.com, Andew Morton Cc: keescook@chromium.org, kernel-hardening@lists.openwall.com List-ID: On Fri, 2017-02-10 at 11:37 -0800, william.c.roberts@intel.com wrote: > From: William Roberts > > Sample output: > WARNING: %pk is close to %pK, did you mean %pK?. > \#20: FILE: drivers/char/applicom.c:230: > + printk(KERN_INFO "Could not allocate IRQ %d for PCI Applicom device. %pk\n", dev->irq, pci_get_class); There isn't a single instance of this in the kernel tree. Maybe if this is really useful, then all the %p extensions should be enumerated and all unknown uses should have warnings. Something like: --- scripts/checkpatch.pl | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl index ad5ea5c545b2..8a90b457e8b5 100755 --- a/scripts/checkpatch.pl +++ b/scripts/checkpatch.pl @@ -5305,6 +5305,15 @@ sub process { } } +# check for vsprintf extension %p misuses + if ($line =~ /\b$logFunctions\s*\(.*$String/) { + my $format = get_quoted_string($line, $rawline); + if ($format =~ /(\%[\*\d\.]*p(?![\WFfSsBKRraEhMmIiUDdgVCbGN]).)/) { + WARN("VSPRINTF_POINTER_EXTENSION", + "Invalid vsprintf pointer extension '$1'\n" . $herecurr); + } + } + # check for logging continuations if ($line =~ /\bprintk\s*\(\s*KERN_CONT\b|\bpr_cont\s*\(/) { WARN("LOGGING_CONTINUATION",