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SubjectRe: [PATCH v2 3/3] checkpatch: warn for use of %px
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On Fri, 2017-12-08 at 08:15 +1100, Tobin C. Harding wrote:
> On Fri, Dec 08, 2017 at 08:06:53AM +1100, Tobin C. Harding wrote:
> > On Wed, Dec 06, 2017 at 02:37:08PM +1100, Tobin C. Harding wrote:
> > > Usage of the new %px specifier potentially leaks sensitive
> > > inforamtion. Printing kernel addresses exposes the kernel layout in
> > > memory, this is potentially exploitable. We have tools in the kernel to
> > > help us do the right thing. We can have checkpatch warn developers of
> > > potential dangers of using %px.
> > >
> > > Have checkpatch emit a warning for usage of specifier %px.
> > >
> > > Signed-off-by: Tobin C. Harding <me@tobin.cc>
> > > Co-developed-by: Joe Perches <joe@perches.com>
> >
> > Co-Developed-by:
> >
> > Woops.
> >
> > Joe I didn't quite understand what you meant when you said that this
> > could go in via any tree. I'm still learning the whole kernel tree
> > management thing. Don't checkpatch patches go in via Andy's tree?
> >
> > https://git.kernel.org/pub/scm/linux/kernel/git/apw/checkpatch.git/
>
> Oh, I see that tree is not super active. If there are no NACK's do you
> want me to put this through my tree? Perhaps once the Co-Developed-by
> stuff is in an acceptable form we could put them all together? Please do
> say if I'm going about things wrong, here to learn.

No worries, you could push it through your tree.

btw: Here's an attempt at the case-sensitive signature matching
---
scripts/checkpatch.pl | 47 ++++++++++++++++++++++++------------------
-----
1 file changed, 24 insertions(+), 23 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 6b130a4116fa..59e8d62e0eb0 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -461,16 +461,18 @@ our $logFunctions = qr{(?x:
seq_vprintf|seq_printf|seq_puts
)};

-our $signature_tags = qr{(?xi:
- Signed-off-by:|
- Acked-by:|
- Tested-by:|
- Reviewed-by:|
- Reported-by:|
- Suggested-by:|
- To:|
- Cc:
-)};
+our @valid_signatures = (
+ "Signed-off-by:",
+ "Acked-by:",
+ "Tested-by:",
+ "Reviewed-by:",
+ "Reported-by:",
+ "Suggested-by:",
+ "Co-Developed-by:",
+ "To:",
+ "Cc:"
+);
+my $signature_tags = "(?x:" . join('|', @valid_signatures) . ")";

our @typeListMisordered = (
qr{char\s+(?:un)?signed},
@@ -2467,35 +2469,34 @@ sub process {
my $sign_off = $2;
my $space_after = $3;
my $email = $4;
- my $ucfirst_sign_off = ucfirst(lc($sign_off));
+ my $preferred_sign_off = ucfirst(lc($sign_off));

- if ($sign_off !~ /$signature_tags/) {
+ if ($sign_off !~ /$signature_tags/i) {
WARN("BAD_SIGN_OFF",
"Non-standard signature: $sign_off\n" . $herecurr);
- }
- if (defined $space_before && $space_before ne "") {
+ } elsif ($sign_off !~ /$signature_tags/) {
+ $preferred_sign_off = $valid_signatures[ grep { $valid_signatures[$_] eq $sign_off } 0..$#valid_signatures ];
if (WARN("BAD_SIGN_OFF",
- "Do not use whitespace before $ucfirst_sign_off\n" . $herecurr) &&
+ "'$preferred_sign_off' is the preferred signature form\n" . $herecurr) &&
$fix) {
- $fixed[$fixlinenr] =
- "$ucfirst_sign_off $email";
+ $fixed[$fixlinenr] = "$preferred_sign_off $email";
}
}
- if ($sign_off =~ /-by:$/i && $sign_off ne $ucfirst_sign_off) {
+ if (defined $space_before && $space_before ne "") {
if (WARN("BAD_SIGN_OFF",
- "'$ucfirst_sign_off' is the preferred signature form\n" . $herecurr) &&
+ "Do not use whitespace before $preferred_sign_off\n" . $herecurr) &&
$fix) {
$fixed[$fixlinenr] =
- "$ucfirst_sign_off $email";
+ "$preferred_sign_off $email";
}
-
}
+
if (!defined $space_after || $space_after ne " ") {
if (WARN("BAD_SIGN_OFF",
- "Use a single space after $ucfirst_sign_off\n" . $herecurr) &&
+ "Use a single space after $preferred_sign_off\n" . $herecurr) &&
$fix) {
$fixed[$fixlinenr] =
- "$ucfirst_sign_off $email";
+ "$preferred_sign_off $email";
}
}

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