* [PATCH] checkpatch: Add --strict test for kmalloc/kzalloc with multiply
@ 2014-05-13 23:48 Joe Perches
2014-05-15 22:58 ` Andrew Morton
0 siblings, 1 reply; 5+ messages in thread
From: Joe Perches @ 2014-05-13 23:48 UTC (permalink / raw)
To: Andrew Morton; +Cc: Andy Whitcroft, LKML
Protect against sizeof overflows by preferring
kmalloc_array and kcalloc to kmalloc/kzalloc
with a sizeof multiply.
Signed-off-by: Joe Perches <joe@perches.com>
---
scripts/checkpatch.pl | 14 ++++++++++++++
1 file changed, 14 insertions(+)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e7ff52a..33eb71f 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4378,6 +4378,20 @@ sub process {
"Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr);
}
+# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
+ if ($^V && $^V ge 5.10.0 &&
+ $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) {
+ my $oldfunc = $3;
+ my $a1 = $4;
+ my $a2 = $10;
+ my $newfunc = "kmalloc_array";
+ $newfunc = "kcalloc" if ($oldfunc eq "kzalloc");
+ if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) {
+ CHK("ALLOC_WITH_MULTIPLY",
+ "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr);
+ }
+ }
+
# check for krealloc arg reuse
if ($^V && $^V ge 5.10.0 &&
$line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*\1\s*,/) {
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] checkpatch: Add --strict test for kmalloc/kzalloc with multiply
2014-05-13 23:48 [PATCH] checkpatch: Add --strict test for kmalloc/kzalloc with multiply Joe Perches
@ 2014-05-15 22:58 ` Andrew Morton
2014-05-15 23:04 ` Joe Perches
0 siblings, 1 reply; 5+ messages in thread
From: Andrew Morton @ 2014-05-15 22:58 UTC (permalink / raw)
To: Joe Perches; +Cc: Andy Whitcroft, LKML
On Tue, 13 May 2014 16:48:49 -0700 Joe Perches <joe@perches.com> wrote:
> Protect against sizeof overflows by preferring
> kmalloc_array and kcalloc to kmalloc/kzalloc
> with a sizeof multiply.
>
> ...
>
> --- a/scripts/checkpatch.pl
> +++ b/scripts/checkpatch.pl
> @@ -4378,6 +4378,20 @@ sub process {
> "Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr);
> }
>
> +# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
> + if ($^V && $^V ge 5.10.0 &&
> + $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) {
> + my $oldfunc = $3;
> + my $a1 = $4;
> + my $a2 = $10;
> + my $newfunc = "kmalloc_array";
> + $newfunc = "kcalloc" if ($oldfunc eq "kzalloc");
> + if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) {
> + CHK("ALLOC_WITH_MULTIPLY",
> + "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr);
> + }
> + }
> +
Why hide this behind --strict?
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] checkpatch: Add --strict test for kmalloc/kzalloc with multiply
2014-05-15 22:58 ` Andrew Morton
@ 2014-05-15 23:04 ` Joe Perches
2014-05-15 23:07 ` Andrew Morton
0 siblings, 1 reply; 5+ messages in thread
From: Joe Perches @ 2014-05-15 23:04 UTC (permalink / raw)
To: Andrew Morton; +Cc: Andy Whitcroft, LKML
On Thu, 2014-05-15 at 15:58 -0700, Andrew Morton wrote:
> On Tue, 13 May 2014 16:48:49 -0700 Joe Perches <joe@perches.com> wrote:
> > Protect against sizeof overflows by preferring
> > kmalloc_array and kcalloc to kmalloc/kzalloc
> > with a sizeof multiply.
[]
> > +# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
> > + if ($^V && $^V ge 5.10.0 &&
> > + $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) {
> > + my $oldfunc = $3;
> > + my $a1 = $4;
> > + my $a2 = $10;
> > + my $newfunc = "kmalloc_array";
> > + $newfunc = "kcalloc" if ($oldfunc eq "kzalloc");
> > + if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) {
> > + CHK("ALLOC_WITH_MULTIPLY",
> > + "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr);
> > + }
> > + }
> > +
>
> Why hide this behind --strict?
Non-obvious CHK/--strict tests are less controversial.
The block above it
"prefer foo = alloc(sizeof(*foo)) over foo = alloc(sizeof(struct bar))"
used CHK so I copied it.
I've no objection to making it WARN instead,
^ permalink raw reply [flat|nested] 5+ messages in thread* Re: [PATCH] checkpatch: Add --strict test for kmalloc/kzalloc with multiply
2014-05-15 23:04 ` Joe Perches
@ 2014-05-15 23:07 ` Andrew Morton
2014-05-15 23:27 ` [PATCH V2] checkpatch: Add warning " Joe Perches
0 siblings, 1 reply; 5+ messages in thread
From: Andrew Morton @ 2014-05-15 23:07 UTC (permalink / raw)
To: Joe Perches; +Cc: Andy Whitcroft, LKML
On Thu, 15 May 2014 16:04:46 -0700 Joe Perches <joe@perches.com> wrote:
> On Thu, 2014-05-15 at 15:58 -0700, Andrew Morton wrote:
> > On Tue, 13 May 2014 16:48:49 -0700 Joe Perches <joe@perches.com> wrote:
> > > Protect against sizeof overflows by preferring
> > > kmalloc_array and kcalloc to kmalloc/kzalloc
> > > with a sizeof multiply.
> []
> > > +# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
> > > + if ($^V && $^V ge 5.10.0 &&
> > > + $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) {
> > > + my $oldfunc = $3;
> > > + my $a1 = $4;
> > > + my $a2 = $10;
> > > + my $newfunc = "kmalloc_array";
> > > + $newfunc = "kcalloc" if ($oldfunc eq "kzalloc");
> > > + if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) {
> > > + CHK("ALLOC_WITH_MULTIPLY",
> > > + "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr);
> > > + }
> > > + }
> > > +
> >
> > Why hide this behind --strict?
>
> Non-obvious CHK/--strict tests are less controversial.
>
> The block above it
> "prefer foo = alloc(sizeof(*foo)) over foo = alloc(sizeof(struct bar))"
> used CHK so I copied it.
>
> I've no objection to making it WARN instead,
I'd prefer that - this is one of my regular comment-on-during-review
things.
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH V2] checkpatch: Add warning for kmalloc/kzalloc with multiply
2014-05-15 23:07 ` Andrew Morton
@ 2014-05-15 23:27 ` Joe Perches
0 siblings, 0 replies; 5+ messages in thread
From: Joe Perches @ 2014-05-15 23:27 UTC (permalink / raw)
To: Andrew Morton; +Cc: Andy Whitcroft, LKML
Protect against sizeof overflows by preferring
kmalloc_array/kcalloc over kmalloc/kzalloc
with a sizeof multiply.
Signed-off-by: Joe Perches <joe@perches.com>
---
V2: Make it a WARN instead.
Add capability to --fix it too.
scripts/checkpatch.pl | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index e7ff52a..7774025 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -4378,6 +4378,30 @@ sub process {
"Prefer $3(sizeof(*$1)...) over $3($4...)\n" . $herecurr);
}
+# check for k[mz]alloc with multiplies that could be kmalloc_array/kcalloc
+ if ($^V && $^V ge 5.10.0 &&
+ $line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/) {
+ my $oldfunc = $3;
+ my $a1 = $4;
+ my $a2 = $10;
+ my $newfunc = "kmalloc_array";
+ $newfunc = "kcalloc" if ($oldfunc eq "kzalloc");
+ if ($a1 =~ /^sizeof\s*\S/ || $a2 =~ /^sizeof\s*\S/) {
+ if (WARN("ALLOC_WITH_MULTIPLY",
+ "Prefer $newfunc over $oldfunc with multiply\n" . $herecurr) &&
+ $fix) {
+ my $r1 = $a1;
+ my $r2 = $a2;
+ if ($a1 =~ /^sizeof\s*\S/) {
+ $r1 = $a2;
+ $r2 = $a1;
+ }
+ $fixed[$linenr - 1] =~ s/\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*(k[mz]alloc)\s*\(\s*($FuncArg)\s*\*\s*($FuncArg)/$1 . ' = ' . "$newfunc(" . trim($r1) . ', ' . trim($r2)/e;
+
+ }
+ }
+ }
+
# check for krealloc arg reuse
if ($^V && $^V ge 5.10.0 &&
$line =~ /\b($Lval)\s*\=\s*(?:$balanced_parens)?\s*krealloc\s*\(\s*\1\s*,/) {
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2014-05-15 23:27 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-05-13 23:48 [PATCH] checkpatch: Add --strict test for kmalloc/kzalloc with multiply Joe Perches
2014-05-15 22:58 ` Andrew Morton
2014-05-15 23:04 ` Joe Perches
2014-05-15 23:07 ` Andrew Morton
2014-05-15 23:27 ` [PATCH V2] checkpatch: Add warning " Joe Perches
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