[Cocci] [PATCH] Coccinelle report script for refcounters

[Cocci] [PATCH] Coccinelle report script for refcounters

[Elena Reshetova]

The below script can be used to detect potential misusage
of atomic_t type and API for reference counting purposes.
Now when we have a dedicated refcount_t type and API with
security protection implemented, people should be using it
instead.

Currently it still reports many occurences since we are
nowhere near the end of our kernel-wide conversion execrise,
but hopefully after couple of cycles more, the amount of
output would be much more limited.

Each script result must be analysed manually before any
conversion, since refcount_t might not suit for certain
purposes (for example if an object is not always destroyed
upon refcounter reaching zero, if increments from zero are
allowed in the code etc.)

As we go further and get less results in output, we will
improve the pattern to detect conversion cases more precisely.

Elena Reshetova (1):
  Coccinelle: add atomic_as_refcounter script

 scripts/coccinelle/api/atomic_as_refcounter.cocci | 102 ++++++++++++++++++++++
 1 file changed, 102 insertions(+)
 create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci

-- 
2.7.4

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Elena Reshetova]

atomic_as_refcounter.cocci script allows detecting
cases when refcount_t type and API should be used
instead of atomic_t.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
---
 scripts/coccinelle/api/atomic_as_refcounter.cocci | 102 ++++++++++++++++++++++
 1 file changed, 102 insertions(+)
 create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci

diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
new file mode 100644
index 0000000..a16d395
--- /dev/null
+++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
@@ -0,0 +1,102 @@
+// Check if refcount_t type and API should be used
+// instead of atomic_t type when dealing with refcounters
+//
+// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
+//
+// Confidence: Moderate
+// URL: http://coccinelle.lip6.fr/
+// Options: --include-headers --very-quiet
+
+virtual report
+
+ at r1 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+identifier fname2 =~ ".*destroy.*";
+identifier fname3 =~ ".*del.*";
+identifier fname4 =~ ".*queue_work.*";
+identifier fname5 =~ ".*schedule_work.*";
+identifier fname6 =~ ".*call_rcu.*";
+
+@@
+
+(
+ atomic_dec_and_test at p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+?y=a
+...
+(
+ fname at p2(a, ...);
+|
+ fname at p2(y, ...);
+|
+ fname2 at p2(...);
+|
+ fname3 at p2(...);
+|
+ fname4 at p2(...);
+|
+ fname5 at p2(...);
+|
+ fname6 at p2(...);
+)
+
+
+ at script:python depends on report@
+p1 << r1.p1;
+p2 << r1.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+@r2 exists@
+identifier a, x;
+position p1;
+@@
+
+(
+atomic_add_unless(&(a)->x,-1,1)@p1
+|
+atomic_long_add_unless(&(a)->x,-1,1)@p1
+|
+atomic64_add_unless(&(a)->x,-1,1)@p1
+)
+
+ at script:python depends on report@
+p1 << r2.p1;
+@@
+msg = "atomic_add_unless"
+coccilib.report.print_report(p1[0], msg)
+
+ at r3 exists@
+identifier x;
+position p1;
+@@
+
+(
+x = atomic_add_return at p1(-1, ...);
+|
+x = atomic_long_add_return at p1(-1, ...);
+|
+x = atomic64_add_return at p1(-1, ...);
+)
+
+@script:python depends on report@
+p1 << r3.p1;
+@@
+msg = "x = atomic_add_return(-1, ...)"
+coccilib.report.print_report(p1[0], msg)
+
+
-- 
2.7.4

[Cocci] [PATCH] Coccinelle report script for refcounters

[Julia Lawall]

On Tue, 18 Jul 2017, Elena Reshetova wrote:

> The below script can be used to detect potential misusage
> of atomic_t type and API for reference counting purposes.
> Now when we have a dedicated refcount_t type and API with
> security protection implemented, people should be using it
> instead.
>
> Currently it still reports many occurences since we are
> nowhere near the end of our kernel-wide conversion execrise,
> but hopefully after couple of cycles more, the amount of
> output would be much more limited.
>
> Each script result must be analysed manually before any
> conversion, since refcount_t might not suit for certain
> purposes (for example if an object is not always destroyed
> upon refcounter reaching zero, if increments from zero are
> allowed in the code etc.)
>
> As we go further and get less results in output, we will
> improve the pattern to detect conversion cases more precisely.

The regexps are the best you can do?

julia

>
> Elena Reshetova (1):
>   Coccinelle: add atomic_as_refcounter script
>
>  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102 ++++++++++++++++++++++
>  1 file changed, 102 insertions(+)
>  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
>
> --
> 2.7.4
>
>

[Cocci] [PATCH] Coccinelle report script for refcounters

[Reshetova, Elena]

> On Tue, 18 Jul 2017, Elena Reshetova wrote:
> 
> > The below script can be used to detect potential misusage
> > of atomic_t type and API for reference counting purposes.
> > Now when we have a dedicated refcount_t type and API with
> > security protection implemented, people should be using it
> > instead.
> >
> > Currently it still reports many occurences since we are
> > nowhere near the end of our kernel-wide conversion execrise,
> > but hopefully after couple of cycles more, the amount of
> > output would be much more limited.
> >
> > Each script result must be analysed manually before any
> > conversion, since refcount_t might not suit for certain
> > purposes (for example if an object is not always destroyed
> > upon refcounter reaching zero, if increments from zero are
> > allowed in the code etc.)
> >
> > As we go further and get less results in output, we will
> > improve the pattern to detect conversion cases more precisely.
> 
> The regexps are the best you can do?

They are simple and so far they were sufficient for the purpose since
they found pretty much all the cases we are aware about. I was thinking
on working to improve the pattern later on after we merge the bulk of
conversions and I have some cycles free on that front.

What would you suggest to do instead of regexps?

Best Regards,
Elena.

> 
> julia
> 
> >
> > Elena Reshetova (1):
> >   Coccinelle: add atomic_as_refcounter script
> >
> >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> ++++++++++++++++++++++
> >  1 file changed, 102 insertions(+)
> >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> >
> > --
> > 2.7.4
> >
> >

[Cocci] [PATCH] Coccinelle report script for refcounters

[Julia Lawall]

On Tue, 18 Jul 2017, Reshetova, Elena wrote:

> > On Tue, 18 Jul 2017, Elena Reshetova wrote:
> >
> > > The below script can be used to detect potential misusage
> > > of atomic_t type and API for reference counting purposes.
> > > Now when we have a dedicated refcount_t type and API with
> > > security protection implemented, people should be using it
> > > instead.
> > >
> > > Currently it still reports many occurences since we are
> > > nowhere near the end of our kernel-wide conversion execrise,
> > > but hopefully after couple of cycles more, the amount of
> > > output would be much more limited.
> > >
> > > Each script result must be analysed manually before any
> > > conversion, since refcount_t might not suit for certain
> > > purposes (for example if an object is not always destroyed
> > > upon refcounter reaching zero, if increments from zero are
> > > allowed in the code etc.)
> > >
> > > As we go further and get less results in output, we will
> > > improve the pattern to detect conversion cases more precisely.
> >
> > The regexps are the best you can do?
>
> They are simple and so far they were sufficient for the purpose since
> they found pretty much all the cases we are aware about. I was thinking
> on working to improve the pattern later on after we merge the bulk of
> conversions and I have some cycles free on that front.
>
> What would you suggest to do instead of regexps?

Is there anything about the definitions of these functions that indicates
why they are important?

julia

>
> Best Regards,
> Elena.
>
> >
> > julia
> >
> > >
> > > Elena Reshetova (1):
> > >   Coccinelle: add atomic_as_refcounter script
> > >
> > >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> > ++++++++++++++++++++++
> > >  1 file changed, 102 insertions(+)
> > >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> > >
> > > --
> > > 2.7.4
> > >
> > >
>

[Cocci] [PATCH] Coccinelle report script for refcounters

[Reshetova, Elena]

> On Tue, 18 Jul 2017, Reshetova, Elena wrote:
> 
> > > On Tue, 18 Jul 2017, Elena Reshetova wrote:
> > >
> > > > The below script can be used to detect potential misusage
> > > > of atomic_t type and API for reference counting purposes.
> > > > Now when we have a dedicated refcount_t type and API with
> > > > security protection implemented, people should be using it
> > > > instead.
> > > >
> > > > Currently it still reports many occurences since we are
> > > > nowhere near the end of our kernel-wide conversion execrise,
> > > > but hopefully after couple of cycles more, the amount of
> > > > output would be much more limited.
> > > >
> > > > Each script result must be analysed manually before any
> > > > conversion, since refcount_t might not suit for certain
> > > > purposes (for example if an object is not always destroyed
> > > > upon refcounter reaching zero, if increments from zero are
> > > > allowed in the code etc.)
> > > >
> > > > As we go further and get less results in output, we will
> > > > improve the pattern to detect conversion cases more precisely.
> > >
> > > The regexps are the best you can do?
> >
> > They are simple and so far they were sufficient for the purpose since
> > they found pretty much all the cases we are aware about. I was thinking
> > on working to improve the pattern later on after we merge the bulk of
> > conversions and I have some cycles free on that front.
> >
> > What would you suggest to do instead of regexps?
> 
> Is there anything about the definitions of these functions that indicates
> why they are important?

I am not sure I understand the question fully. Do you mean the functions
used in the rules, such as atomic_dec_and_test() etc.?
If yes, then for example the combination of atomic_dec_and_test(&(a)->x)
on a pointer, then followed later by some kind of *free*(a) function (kfree, kmem_cache_free() etc.)
on that pointer is a quite common indicator that we are dealing with a reference counter since
they would normally free resources when counter reaches zero. 
Again, it is not a 100% indicator since I have seen weird schemes that for example
free a resource upon reaching -1, or free it in one case and don't free on another,
but such cases are more rare. 

Does this answer your questions?

Best Regards,
Elena.

> 
> julia
> 
> >
> > Best Regards,
> > Elena.
> >
> > >
> > > julia
> > >
> > > >
> > > > Elena Reshetova (1):
> > > >   Coccinelle: add atomic_as_refcounter script
> > > >
> > > >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> > > ++++++++++++++++++++++
> > > >  1 file changed, 102 insertions(+)
> > > >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > >
> > > > --
> > > > 2.7.4
> > > >
> > > >
> >

[Cocci] [PATCH] Coccinelle report script for refcounters

[Julia Lawall]

On Tue, 18 Jul 2017, Reshetova, Elena wrote:

> > On Tue, 18 Jul 2017, Reshetova, Elena wrote:
> >
> > > > On Tue, 18 Jul 2017, Elena Reshetova wrote:
> > > >
> > > > > The below script can be used to detect potential misusage
> > > > > of atomic_t type and API for reference counting purposes.
> > > > > Now when we have a dedicated refcount_t type and API with
> > > > > security protection implemented, people should be using it
> > > > > instead.
> > > > >
> > > > > Currently it still reports many occurences since we are
> > > > > nowhere near the end of our kernel-wide conversion execrise,
> > > > > but hopefully after couple of cycles more, the amount of
> > > > > output would be much more limited.
> > > > >
> > > > > Each script result must be analysed manually before any
> > > > > conversion, since refcount_t might not suit for certain
> > > > > purposes (for example if an object is not always destroyed
> > > > > upon refcounter reaching zero, if increments from zero are
> > > > > allowed in the code etc.)
> > > > >
> > > > > As we go further and get less results in output, we will
> > > > > improve the pattern to detect conversion cases more precisely.
> > > >
> > > > The regexps are the best you can do?
> > >
> > > They are simple and so far they were sufficient for the purpose since
> > > they found pretty much all the cases we are aware about. I was thinking
> > > on working to improve the pattern later on after we merge the bulk of
> > > conversions and I have some cycles free on that front.
> > >
> > > What would you suggest to do instead of regexps?
> >
> > Is there anything about the definitions of these functions that indicates
> > why they are important?
>
> I am not sure I understand the question fully. Do you mean the functions
> used in the rules, such as atomic_dec_and_test() etc.?
> If yes, then for example the combination of atomic_dec_and_test(&(a)->x)
> on a pointer, then followed later by some kind of *free*(a) function (kfree, kmem_cache_free() etc.)
> on that pointer is a quite common indicator that we are dealing with a reference counter since
> they would normally free resources when counter reaches zero.
> Again, it is not a 100% indicator since I have seen weird schemes that for example
> free a resource upon reaching -1, or free it in one case and don't free on another,
> but such cases are more rare.

I just meant that the name of the function is not always reliable.  Maybe
there is some other property of the definition of the function, like being
a wrapper for kfree, that would be more reliable.  But in this case it is
quite possible that there is not.  We can try with the rule as is and see
what happens.

julia


>
> Does this answer your questions?
>
> Best Regards,
> Elena.
>
> >
> > julia
> >
> > >
> > > Best Regards,
> > > Elena.
> > >
> > > >
> > > > julia
> > > >
> > > > >
> > > > > Elena Reshetova (1):
> > > > >   Coccinelle: add atomic_as_refcounter script
> > > > >
> > > > >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> > > > ++++++++++++++++++++++
> > > > >  1 file changed, 102 insertions(+)
> > > > >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > > >
> > > > > --
> > > > > 2.7.4
> > > > >
> > > > >
> > >
>

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Kees Cook]

On Tue, Jul 18, 2017 at 12:48 AM, Elena Reshetova
<elena.reshetova@intel.com> wrote:
> atomic_as_refcounter.cocci script allows detecting
> cases when refcount_t type and API should be used
> instead of atomic_t.
>
> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> ---
>  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102 ++++++++++++++++++++++
>  1 file changed, 102 insertions(+)
>  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
>
> diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> new file mode 100644
> index 0000000..a16d395
> --- /dev/null
> +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> @@ -0,0 +1,102 @@
> +// Check if refcount_t type and API should be used
> +// instead of atomic_t type when dealing with refcounters
> +//
> +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> +//
> +// Confidence: Moderate
> +// URL: http://coccinelle.lip6.fr/
> +// Options: --include-headers --very-quiet
> +
> +virtual report
> +
> + at r1 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> [...]
> +)
> +...
> +?y=a
> +...
> +(
> + fname at p2(a, ...);
> +|
> + fname at p2(y, ...);
> +|
> [...]

Just to double check, this "?y=a" catches the seccomp case I pointed out?

        while (orig && atomic_dec_and_test(&orig->usage)) {
                struct seccomp_filter *freeme = orig;
                orig = orig->prev;
                seccomp_filter_free(freeme);
        }

Seems like it should match. Did this find anything else besides seccomp?

-Kees

-- 
Kees Cook
Pixel Security

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Reshetova, Elena]

 On Tue, Jul 18, 2017 at 12:48 AM, Elena Reshetova
> <elena.reshetova@intel.com> wrote:
> > atomic_as_refcounter.cocci script allows detecting
> > cases when refcount_t type and API should be used
> > instead of atomic_t.
> >
> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> > ---
> >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> ++++++++++++++++++++++
> >  1 file changed, 102 insertions(+)
> >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> >
> > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci
> b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > new file mode 100644
> > index 0000000..a16d395
> > --- /dev/null
> > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > @@ -0,0 +1,102 @@
> > +// Check if refcount_t type and API should be used
> > +// instead of atomic_t type when dealing with refcounters
> > +//
> > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > +//
> > +// Confidence: Moderate
> > +// URL: http://coccinelle.lip6.fr/
> > +// Options: --include-headers --very-quiet
> > +
> > +virtual report
> > +
> > + at r1 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > [...]
> > +)
> > +...
> > +?y=a
> > +...
> > +(
> > + fname at p2(a, ...);
> > +|
> > + fname at p2(y, ...);
> > +|
> > [...]
> 
> Just to double check, this "?y=a" catches the seccomp case I pointed out?
> 
>         while (orig && atomic_dec_and_test(&orig->usage)) {
>                 struct seccomp_filter *freeme = orig;
>                 orig = orig->prev;
>                 seccomp_filter_free(freeme);
>         }
> 

Yes, it does find the seccomp case, I was specifically testing this new addition on it. 


> Seems like it should match. Did this find anything else besides seccomp?

Yes, it found about 20 new things, but I haven't had a chance to look at them all yet.
In any case, I would really love to merge the existing conversions first (we still have about 80 patches left)
and only after add more of them. I looked at some new found cases and for example this was one:

./crypto/cryptd.c:474:38-57: atomic_dec_and_test variation before object free at line 475.

static void cryptd_skcipher_complete(struct skcipher_request *req, int err)
{
    struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
    struct cryptd_skcipher_ctx *ctx = crypto_skcipher_ctx(tfm);
    struct cryptd_skcipher_request_ctx *rctx = skcipher_request_ctx(req);
    int refcnt = atomic_read(&ctx->refcnt);

    local_bh_disable();
    rctx->complete(&req->base, err);
    local_bh_enable();

    if (err != -EINPROGRESS && refcnt && atomic_dec_and_test(&ctx->refcnt))
        crypto_free_skcipher(tfm);
}

While it isn't exactly the case I had in mind when trying to modify the pattern to work
for seccomp case, it came as a nice bonus IMO since we do want to catch these cases as well.
Overall it seems that pointers/structures can be so nicely wrapped around in some cases,
that keeping the pattern as generic as possible is a good way to go. Otherwise we might
start losing cases ( I would prefer a bit more false positives in this case instead as soon as
they are fine to manage). 

Best Regards,
Elena.

> 
> -Kees
> 
> --
> Kees Cook
> Pixel Security

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Julia Lawall]

On Tue, 18 Jul 2017, Elena Reshetova wrote:

> atomic_as_refcounter.cocci script allows detecting
> cases when refcount_t type and API should be used
> instead of atomic_t.
>
> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> ---
>  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102 ++++++++++++++++++++++
>  1 file changed, 102 insertions(+)
>  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
>
> diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> new file mode 100644
> index 0000000..a16d395
> --- /dev/null
> +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> @@ -0,0 +1,102 @@
> +// Check if refcount_t type and API should be used
> +// instead of atomic_t type when dealing with refcounters
> +//
> +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> +//
> +// Confidence: Moderate
> +// URL: http://coccinelle.lip6.fr/
> +// Options: --include-headers --very-quiet
> +
> +virtual report
> +
> + at r1 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +?y=a

This makes the line optional. And if it dosn't appear, there is no
constraint on y.  So the rule matches:

int main() {
  atomic64_dec_and_test(&(a)->x);
  free(b);
}

I would suggest to just make two rules, one with y=a and one without.

julia

> +...
> +(
> + fname at p2(a, ...);
> +|
> + fname at p2(y, ...);
> +|
> + fname2 at p2(...);
> +|
> + fname3 at p2(...);
> +|
> + fname4 at p2(...);
> +|
> + fname5 at p2(...);
> +|
> + fname6 at p2(...);
> +)
> +
> +
> + at script:python depends on report@
> +p1 << r1.p1;
> +p2 << r1.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r2 exists@
> +identifier a, x;
> +position p1;
> +@@
> +
> +(
> +atomic_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic_long_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic64_add_unless(&(a)->x,-1,1)@p1
> +)
> +
> + at script:python depends on report@
> +p1 << r2.p1;
> +@@
> +msg = "atomic_add_unless"
> +coccilib.report.print_report(p1[0], msg)
> +
> + at r3 exists@
> +identifier x;
> +position p1;
> +@@
> +
> +(
> +x = atomic_add_return at p1(-1, ...);
> +|
> +x = atomic_long_add_return at p1(-1, ...);
> +|
> +x = atomic64_add_return at p1(-1, ...);
> +)
> +
> + at script:python depends on report@
> +p1 << r3.p1;
> +@@
> +msg = "x = atomic_add_return(-1, ...)"
> +coccilib.report.print_report(p1[0], msg)
> +
> +
> --
> 2.7.4
>
>

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Reshetova, Elena]

> On Tue, 18 Jul 2017, Elena Reshetova wrote:
> 
> > atomic_as_refcounter.cocci script allows detecting
> > cases when refcount_t type and API should be used
> > instead of atomic_t.
> >
> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> > ---
> >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 102
> ++++++++++++++++++++++
> >  1 file changed, 102 insertions(+)
> >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> >
> > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci
> b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > new file mode 100644
> > index 0000000..a16d395
> > --- /dev/null
> > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > @@ -0,0 +1,102 @@
> > +// Check if refcount_t type and API should be used
> > +// instead of atomic_t type when dealing with refcounters
> > +//
> > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > +//
> > +// Confidence: Moderate
> > +// URL: http://coccinelle.lip6.fr/
> > +// Options: --include-headers --very-quiet
> > +
> > +virtual report
> > +
> > + at r1 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +?y=a
> 
> This makes the line optional. And if it dosn't appear, there is no
> constraint on y.  So the rule matches:
> 
> int main() {
>   atomic64_dec_and_test(&(a)->x);
>   free(b);
> }
> 
> I would suggest to just make two rules, one with y=a and one without.

Oh, thank you for the catch! I was a bit afraid it might be the case, but when
I tried it in practice it didn't show up that many additional cases compare to
not having ?y=a at all (only 20 or so), and when I checked some, they looked
worth a manual check anyway and interesting. 

But I will fix the rule and send a new version!

Best Regards,
Elena.

> 
> julia
> 
> > +...
> > +(
> > + fname at p2(a, ...);
> > +|
> > + fname at p2(y, ...);
> > +|
> > + fname2 at p2(...);
> > +|
> > + fname3 at p2(...);
> > +|
> > + fname4 at p2(...);
> > +|
> > + fname5 at p2(...);
> > +|
> > + fname6 at p2(...);
> > +)
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r1.p1;
> > +p2 << r1.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r2 exists@
> > +identifier a, x;
> > +position p1;
> > +@@
> > +
> > +(
> > +atomic_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic_long_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic64_add_unless(&(a)->x,-1,1)@p1
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r2.p1;
> > +@@
> > +msg = "atomic_add_unless"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > + at r3 exists@
> > +identifier x;
> > +position p1;
> > +@@
> > +
> > +(
> > +x = atomic_add_return at p1(-1, ...);
> > +|
> > +x = atomic_long_add_return at p1(-1, ...);
> > +|
> > +x = atomic64_add_return at p1(-1, ...);
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r3.p1;
> > +@@
> > +msg = "x = atomic_add_return(-1, ...)"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > +
> > --
> > 2.7.4
> >
> >

[Cocci] add atomic_as_refcounter script

[SF Markus Elfring]

Dear Elena,

I have also taken another look at your script.

The SmPL rule ?r1? specifies six metavariables for identifiers. It seems that
the names ?fname3? till ?fname6? do not care for different function parameters
in the SmPL disjunction at the end.
How do you think about to reduce this disjunction by using a regular expression
with an alternation like ?.*(?:call_rcu|del|queue_work|schedule_work).*?
for a constraint?

Will it help to refactor another rule a bit?

@r3 exists@
identifier x;
position p1;
@@
 x =
(
 atomic_add_return at p1(-1, ...);
|
 atomic_long_add_return at p1(-1, ...);
|
 atomic64_add_return at p1(-1, ...);
)


Regards,
Markus

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Masahiro Yamada]

2018-06-15 14:06 GMT+09:00 Julia Lawall <julia.lawall@lip6.fr>:
>
>
> On Thu, 14 Jun 2018, Kees Cook wrote:
>
>> On Fri, Sep 1, 2017 at 2:40 AM, Elena Reshetova
>> <elena.reshetova@intel.com> wrote:
>> > atomic_as_refcounter.cocci script allows detecting
>> > cases when refcount_t type and API should be used
>> > instead of atomic_t.
>> >
>> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
>> > Acked-by: Julia Lawall <julia.lawall@lip6.fr>
>>
>> Reviewed-by: Kees Cook <keescook@chromium.org>
>>
>> Oops, I think this got lost. Who can take this patch? I thought Julia
>> ran the scripts/coccinelle/ tree, but looking at git log, it looks
>> more like it's Masahiro? Either way, let's get this in the tree. Who
>> can take it?
>
> Masahiro takes patches.
>
> julia


Somehow I missed this one.
Now, applied to linux-kbuild.  Thanks for the reminder.

(If Julia hosted a git repository, that would be better, though.)


-- 
Best Regards
Masahiro Yamada

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Julia Lawall]

On Thu, 14 Jun 2018, Kees Cook wrote:

> On Fri, Sep 1, 2017 at 2:40 AM, Elena Reshetova
> <elena.reshetova@intel.com> wrote:
> > atomic_as_refcounter.cocci script allows detecting
> > cases when refcount_t type and API should be used
> > instead of atomic_t.
> >
> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> > Acked-by: Julia Lawall <julia.lawall@lip6.fr>
>
> Reviewed-by: Kees Cook <keescook@chromium.org>
>
> Oops, I think this got lost. Who can take this patch? I thought Julia
> ran the scripts/coccinelle/ tree, but looking at git log, it looks
> more like it's Masahiro? Either way, let's get this in the tree. Who
> can take it?

Masahiro takes patches.

julia

>
> Thanks!
>
> -Kees
>
> > ---
> >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 131 ++++++++++++++++++++++
> >  1 file changed, 131 insertions(+)
> >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> >
> > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > new file mode 100644
> > index 0000000..bfa880d
> > --- /dev/null
> > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > @@ -0,0 +1,131 @@
> > +// Check if refcount_t type and API should be used
> > +// instead of atomic_t type when dealing with refcounters
> > +//
> > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > +//
> > +// Confidence: Moderate
> > +// URL: http://coccinelle.lip6.fr/
> > +// Options: --include-headers --very-quiet
> > +
> > +virtual report
> > +
> > + at r1 exists@
> > +identifier a, x;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +(
> > + fname at p2(a, ...);
> > +|
> > + fname2 at p2(...);
> > +|
> > + fname3 at p2(...);
> > +|
> > + fname4 at p2(...);
> > +|
> > + fname5 at p2(...);
> > +|
> > + fname6 at p2(...);
> > +)
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r1.p1;
> > +p2 << r1.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r4 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +y=a
> > +...
> > +fname at p2(y, ...);
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r4.p1;
> > +p2 << r4.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r2 exists@
> > +identifier a, x;
> > +position p1;
> > +@@
> > +
> > +(
> > +atomic_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic_long_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic64_add_unless(&(a)->x,-1,1)@p1
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r2.p1;
> > +@@
> > +msg = "atomic_add_unless"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > + at r3 exists@
> > +identifier x;
> > +position p1;
> > +@@
> > +
> > +(
> > +x = atomic_add_return at p1(-1, ...);
> > +|
> > +x = atomic_long_add_return at p1(-1, ...);
> > +|
> > +x = atomic64_add_return at p1(-1, ...);
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r3.p1;
> > +@@
> > +msg = "x = atomic_add_return(-1, ...)"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > +
> > --
> > 2.7.4
> >
>
>
>
> --
> Kees Cook
> Pixel Security
>

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Kees Cook]

On Fri, Sep 1, 2017 at 2:40 AM, Elena Reshetova
<elena.reshetova@intel.com> wrote:
> atomic_as_refcounter.cocci script allows detecting
> cases when refcount_t type and API should be used
> instead of atomic_t.
>
> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> Acked-by: Julia Lawall <julia.lawall@lip6.fr>

Reviewed-by: Kees Cook <keescook@chromium.org>

Oops, I think this got lost. Who can take this patch? I thought Julia
ran the scripts/coccinelle/ tree, but looking at git log, it looks
more like it's Masahiro? Either way, let's get this in the tree. Who
can take it?

Thanks!

-Kees

> ---
>  scripts/coccinelle/api/atomic_as_refcounter.cocci | 131 ++++++++++++++++++++++
>  1 file changed, 131 insertions(+)
>  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
>
> diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> new file mode 100644
> index 0000000..bfa880d
> --- /dev/null
> +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> @@ -0,0 +1,131 @@
> +// Check if refcount_t type and API should be used
> +// instead of atomic_t type when dealing with refcounters
> +//
> +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> +//
> +// Confidence: Moderate
> +// URL: http://coccinelle.lip6.fr/
> +// Options: --include-headers --very-quiet
> +
> +virtual report
> +
> + at r1 exists@
> +identifier a, x;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +(
> + fname at p2(a, ...);
> +|
> + fname2 at p2(...);
> +|
> + fname3 at p2(...);
> +|
> + fname4 at p2(...);
> +|
> + fname5 at p2(...);
> +|
> + fname6 at p2(...);
> +)
> +
> +
> + at script:python depends on report@
> +p1 << r1.p1;
> +p2 << r1.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r4 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +y=a
> +...
> +fname at p2(y, ...);
> +
> +
> + at script:python depends on report@
> +p1 << r4.p1;
> +p2 << r4.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r2 exists@
> +identifier a, x;
> +position p1;
> +@@
> +
> +(
> +atomic_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic_long_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic64_add_unless(&(a)->x,-1,1)@p1
> +)
> +
> + at script:python depends on report@
> +p1 << r2.p1;
> +@@
> +msg = "atomic_add_unless"
> +coccilib.report.print_report(p1[0], msg)
> +
> + at r3 exists@
> +identifier x;
> +position p1;
> +@@
> +
> +(
> +x = atomic_add_return at p1(-1, ...);
> +|
> +x = atomic_long_add_return at p1(-1, ...);
> +|
> +x = atomic64_add_return at p1(-1, ...);
> +)
> +
> + at script:python depends on report@
> +p1 << r3.p1;
> +@@
> +msg = "x = atomic_add_return(-1, ...)"
> +coccilib.report.print_report(p1[0], msg)
> +
> +
> --
> 2.7.4
>



-- 
Kees Cook
Pixel Security

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Elena Reshetova]

atomic_as_refcounter.cocci script allows detecting
cases when refcount_t type and API should be used
instead of atomic_t.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
---
 scripts/coccinelle/api/atomic_as_refcounter.cocci | 131 ++++++++++++++++++++++
 1 file changed, 131 insertions(+)
 create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci

diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
new file mode 100644
index 0000000..bfa880d
--- /dev/null
+++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
@@ -0,0 +1,131 @@
+// Check if refcount_t type and API should be used
+// instead of atomic_t type when dealing with refcounters
+//
+// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
+//
+// Confidence: Moderate
+// URL: http://coccinelle.lip6.fr/
+// Options: --include-headers --very-quiet
+
+virtual report
+
+ at r1 exists@
+identifier a, x;
+position p1, p2;
+identifier fname =~ ".*free.*";
+identifier fname2 =~ ".*destroy.*";
+identifier fname3 =~ ".*del.*";
+identifier fname4 =~ ".*queue_work.*";
+identifier fname5 =~ ".*schedule_work.*";
+identifier fname6 =~ ".*call_rcu.*";
+
+@@
+
+(
+ atomic_dec_and_test at p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+(
+ fname at p2(a, ...);
+|
+ fname2 at p2(...);
+|
+ fname3 at p2(...);
+|
+ fname4 at p2(...);
+|
+ fname5 at p2(...);
+|
+ fname6 at p2(...);
+)
+
+
+ at script:python depends on report@
+p1 << r1.p1;
+p2 << r1.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+ at r4 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+
+@@
+
+(
+ atomic_dec_and_test@p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+y=a
+...
+fname at p2(y, ...);
+
+
+ at script:python depends on report@
+p1 << r4.p1;
+p2 << r4.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+@r2 exists@
+identifier a, x;
+position p1;
+@@
+
+(
+atomic_add_unless(&(a)->x,-1,1)@p1
+|
+atomic_long_add_unless(&(a)->x,-1,1)@p1
+|
+atomic64_add_unless(&(a)->x,-1,1)@p1
+)
+
+ at script:python depends on report@
+p1 << r2.p1;
+@@
+msg = "atomic_add_unless"
+coccilib.report.print_report(p1[0], msg)
+
+ at r3 exists@
+identifier x;
+position p1;
+@@
+
+(
+x = atomic_add_return at p1(-1, ...);
+|
+x = atomic_long_add_return at p1(-1, ...);
+|
+x = atomic64_add_return at p1(-1, ...);
+)
+
+@script:python depends on report@
+p1 << r3.p1;
+@@
+msg = "x = atomic_add_return(-1, ...)"
+coccilib.report.print_report(p1[0], msg)
+
+
-- 
2.7.4

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Reshetova, Elena]

> On Wed, 30 Aug 2017, Reshetova, Elena wrote:
> 
> >
> > >
> > > On Wed, 30 Aug 2017, Elena Reshetova wrote:
> > >
> > > > atomic_as_refcounter.cocci script allows detecting
> > > > cases when refcount_t type and API should be used
> > > > instead of atomic_t.
> > > >
> > > > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> > >
> > > Acked-by: Julia Lawall <julia.lawall@lip6.fr>
> >
> > Thank you very much Julia! What is the correct path to merge this?
> > I will resend with your acked-by, but what is the tree that should merge it?
> 
> Marek will take it.  If you want to resend, please get rid of the
> metavariable y in the rule r1. It causes an unused variable warning.

Sure, will do. Thank you!

Best Regards,
Elena.
> 
> julia
> 
> >
> > Best Regards,
> > Elena.
> > >
> > > > ---
> > > >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 131
> > > ++++++++++++++++++++++
> > > >  1 file changed, 131 insertions(+)
> > > >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > >
> > > > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > > new file mode 100644
> > > > index 0000000..f83771b
> > > > --- /dev/null
> > > > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > > @@ -0,0 +1,131 @@
> > > > +// Check if refcount_t type and API should be used
> > > > +// instead of atomic_t type when dealing with refcounters
> > > > +//
> > > > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > > > +//
> > > > +// Confidence: Moderate
> > > > +// URL: http://coccinelle.lip6.fr/
> > > > +// Options: --include-headers --very-quiet
> > > > +
> > > > +virtual report
> > > > +
> > > > + at r1 exists@
> > > > +identifier a, x, y;
> > > > +position p1, p2;
> > > > +identifier fname =~ ".*free.*";
> > > > +identifier fname2 =~ ".*destroy.*";
> > > > +identifier fname3 =~ ".*del.*";
> > > > +identifier fname4 =~ ".*queue_work.*";
> > > > +identifier fname5 =~ ".*schedule_work.*";
> > > > +identifier fname6 =~ ".*call_rcu.*";
> > > > +
> > > > +@@
> > > > +
> > > > +(
> > > > + atomic_dec_and_test at p1(&(a)->x)
> > > > +|
> > > > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > > > +|
> > > > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > > > +|
> > > > + atomic_long_dec_and_test at p1(&(a)->x)
> > > > +|
> > > > + atomic64_dec_and_test at p1(&(a)->x)
> > > > +|
> > > > + local_dec_and_test at p1(&(a)->x)
> > > > +)
> > > > +...
> > > > +(
> > > > + fname at p2(a, ...);
> > > > +|
> > > > + fname2 at p2(...);
> > > > +|
> > > > + fname3 at p2(...);
> > > > +|
> > > > + fname4 at p2(...);
> > > > +|
> > > > + fname5 at p2(...);
> > > > +|
> > > > + fname6 at p2(...);
> > > > +)
> > > > +
> > > > +
> > > > + at script:python depends on report@
> > > > +p1 << r1.p1;
> > > > +p2 << r1.p2;
> > > > +@@
> > > > +msg = "atomic_dec_and_test variation before object free at line %s."
> > > > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > > > +
> > > > + at r4 exists@
> > > > +identifier a, x, y;
> > > > +position p1, p2;
> > > > +identifier fname =~ ".*free.*";
> > > > +
> > > > +@@
> > > > +
> > > > +(
> > > > + atomic_dec_and_test at p1(&(a)->x)
> > > > +|
> > > > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > > > +|
> > > > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > > > +|
> > > > + atomic_long_dec_and_test at p1(&(a)->x)
> > > > +|
> > > > + atomic64_dec_and_test at p1(&(a)->x)
> > > > +|
> > > > + local_dec_and_test at p1(&(a)->x)
> > > > +)
> > > > +...
> > > > +y=a
> > > > +...
> > > > +fname at p2(y, ...);
> > > > +
> > > > +
> > > > + at script:python depends on report@
> > > > +p1 << r4.p1;
> > > > +p2 << r4.p2;
> > > > +@@
> > > > +msg = "atomic_dec_and_test variation before object free at line %s."
> > > > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > > > +
> > > > + at r2 exists@
> > > > +identifier a, x;
> > > > +position p1;
> > > > +@@
> > > > +
> > > > +(
> > > > +atomic_add_unless(&(a)->x,-1,1)@p1
> > > > +|
> > > > +atomic_long_add_unless(&(a)->x,-1,1)@p1
> > > > +|
> > > > +atomic64_add_unless(&(a)->x,-1,1)@p1
> > > > +)
> > > > +
> > > > + at script:python depends on report@
> > > > +p1 << r2.p1;
> > > > +@@
> > > > +msg = "atomic_add_unless"
> > > > +coccilib.report.print_report(p1[0], msg)
> > > > +
> > > > + at r3 exists@
> > > > +identifier x;
> > > > +position p1;
> > > > +@@
> > > > +
> > > > +(
> > > > +x = atomic_add_return at p1(-1, ...);
> > > > +|
> > > > +x = atomic_long_add_return at p1(-1, ...);
> > > > +|
> > > > +x = atomic64_add_return at p1(-1, ...);
> > > > +)
> > > > +
> > > > + at script:python depends on report@
> > > > +p1 << r3.p1;
> > > > +@@
> > > > +msg = "x = atomic_add_return(-1, ...)"
> > > > +coccilib.report.print_report(p1[0], msg)
> > > > +
> > > > +
> > > > --
> > > > 2.7.4
> > > >
> > > >
> >

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Julia Lawall]

On Wed, 30 Aug 2017, Reshetova, Elena wrote:

>
> >
> > On Wed, 30 Aug 2017, Elena Reshetova wrote:
> >
> > > atomic_as_refcounter.cocci script allows detecting
> > > cases when refcount_t type and API should be used
> > > instead of atomic_t.
> > >
> > > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> >
> > Acked-by: Julia Lawall <julia.lawall@lip6.fr>
>
> Thank you very much Julia! What is the correct path to merge this?
> I will resend with your acked-by, but what is the tree that should merge it?

Marek will take it.  If you want to resend, please get rid of the
metavariable y in the rule r1. It causes an unused variable warning.

julia

>
> Best Regards,
> Elena.
> >
> > > ---
> > >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 131
> > ++++++++++++++++++++++
> > >  1 file changed, 131 insertions(+)
> > >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> > >
> > > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > new file mode 100644
> > > index 0000000..f83771b
> > > --- /dev/null
> > > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > > @@ -0,0 +1,131 @@
> > > +// Check if refcount_t type and API should be used
> > > +// instead of atomic_t type when dealing with refcounters
> > > +//
> > > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > > +//
> > > +// Confidence: Moderate
> > > +// URL: http://coccinelle.lip6.fr/
> > > +// Options: --include-headers --very-quiet
> > > +
> > > +virtual report
> > > +
> > > + at r1 exists@
> > > +identifier a, x, y;
> > > +position p1, p2;
> > > +identifier fname =~ ".*free.*";
> > > +identifier fname2 =~ ".*destroy.*";
> > > +identifier fname3 =~ ".*del.*";
> > > +identifier fname4 =~ ".*queue_work.*";
> > > +identifier fname5 =~ ".*schedule_work.*";
> > > +identifier fname6 =~ ".*call_rcu.*";
> > > +
> > > +@@
> > > +
> > > +(
> > > + atomic_dec_and_test at p1(&(a)->x)
> > > +|
> > > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > > +|
> > > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > > +|
> > > + atomic_long_dec_and_test at p1(&(a)->x)
> > > +|
> > > + atomic64_dec_and_test at p1(&(a)->x)
> > > +|
> > > + local_dec_and_test at p1(&(a)->x)
> > > +)
> > > +...
> > > +(
> > > + fname at p2(a, ...);
> > > +|
> > > + fname2 at p2(...);
> > > +|
> > > + fname3 at p2(...);
> > > +|
> > > + fname4 at p2(...);
> > > +|
> > > + fname5 at p2(...);
> > > +|
> > > + fname6 at p2(...);
> > > +)
> > > +
> > > +
> > > + at script:python depends on report@
> > > +p1 << r1.p1;
> > > +p2 << r1.p2;
> > > +@@
> > > +msg = "atomic_dec_and_test variation before object free at line %s."
> > > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > > +
> > > + at r4 exists@
> > > +identifier a, x, y;
> > > +position p1, p2;
> > > +identifier fname =~ ".*free.*";
> > > +
> > > +@@
> > > +
> > > +(
> > > + atomic_dec_and_test at p1(&(a)->x)
> > > +|
> > > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > > +|
> > > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > > +|
> > > + atomic_long_dec_and_test at p1(&(a)->x)
> > > +|
> > > + atomic64_dec_and_test at p1(&(a)->x)
> > > +|
> > > + local_dec_and_test at p1(&(a)->x)
> > > +)
> > > +...
> > > +y=a
> > > +...
> > > +fname at p2(y, ...);
> > > +
> > > +
> > > + at script:python depends on report@
> > > +p1 << r4.p1;
> > > +p2 << r4.p2;
> > > +@@
> > > +msg = "atomic_dec_and_test variation before object free at line %s."
> > > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > > +
> > > + at r2 exists@
> > > +identifier a, x;
> > > +position p1;
> > > +@@
> > > +
> > > +(
> > > +atomic_add_unless(&(a)->x,-1,1)@p1
> > > +|
> > > +atomic_long_add_unless(&(a)->x,-1,1)@p1
> > > +|
> > > +atomic64_add_unless(&(a)->x,-1,1)@p1
> > > +)
> > > +
> > > + at script:python depends on report@
> > > +p1 << r2.p1;
> > > +@@
> > > +msg = "atomic_add_unless"
> > > +coccilib.report.print_report(p1[0], msg)
> > > +
> > > + at r3 exists@
> > > +identifier x;
> > > +position p1;
> > > +@@
> > > +
> > > +(
> > > +x = atomic_add_return at p1(-1, ...);
> > > +|
> > > +x = atomic_long_add_return at p1(-1, ...);
> > > +|
> > > +x = atomic64_add_return at p1(-1, ...);
> > > +)
> > > +
> > > + at script:python depends on report@
> > > +p1 << r3.p1;
> > > +@@
> > > +msg = "x = atomic_add_return(-1, ...)"
> > > +coccilib.report.print_report(p1[0], msg)
> > > +
> > > +
> > > --
> > > 2.7.4
> > >
> > >
>

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Reshetova, Elena]

> 
> On Wed, 30 Aug 2017, Elena Reshetova wrote:
> 
> > atomic_as_refcounter.cocci script allows detecting
> > cases when refcount_t type and API should be used
> > instead of atomic_t.
> >
> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> 
> Acked-by: Julia Lawall <julia.lawall@lip6.fr>

Thank you very much Julia! What is the correct path to merge this?
I will resend with your acked-by, but what is the tree that should merge it?

Best Regards,
Elena.
> 
> > ---
> >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 131
> ++++++++++++++++++++++
> >  1 file changed, 131 insertions(+)
> >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> >
> > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci
> b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > new file mode 100644
> > index 0000000..f83771b
> > --- /dev/null
> > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > @@ -0,0 +1,131 @@
> > +// Check if refcount_t type and API should be used
> > +// instead of atomic_t type when dealing with refcounters
> > +//
> > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > +//
> > +// Confidence: Moderate
> > +// URL: http://coccinelle.lip6.fr/
> > +// Options: --include-headers --very-quiet
> > +
> > +virtual report
> > +
> > + at r1 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +(
> > + fname at p2(a, ...);
> > +|
> > + fname2 at p2(...);
> > +|
> > + fname3 at p2(...);
> > +|
> > + fname4 at p2(...);
> > +|
> > + fname5 at p2(...);
> > +|
> > + fname6 at p2(...);
> > +)
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r1.p1;
> > +p2 << r1.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r4 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +y=a
> > +...
> > +fname at p2(y, ...);
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r4.p1;
> > +p2 << r4.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r2 exists@
> > +identifier a, x;
> > +position p1;
> > +@@
> > +
> > +(
> > +atomic_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic_long_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic64_add_unless(&(a)->x,-1,1)@p1
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r2.p1;
> > +@@
> > +msg = "atomic_add_unless"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > + at r3 exists@
> > +identifier x;
> > +position p1;
> > +@@
> > +
> > +(
> > +x = atomic_add_return at p1(-1, ...);
> > +|
> > +x = atomic_long_add_return at p1(-1, ...);
> > +|
> > +x = atomic64_add_return at p1(-1, ...);
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r3.p1;
> > +@@
> > +msg = "x = atomic_add_return(-1, ...)"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > +
> > --
> > 2.7.4
> >
> >

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Julia Lawall]

On Wed, 30 Aug 2017, Elena Reshetova wrote:

> atomic_as_refcounter.cocci script allows detecting
> cases when refcount_t type and API should be used
> instead of atomic_t.
>
> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>

Acked-by: Julia Lawall <julia.lawall@lip6.fr>

> ---
>  scripts/coccinelle/api/atomic_as_refcounter.cocci | 131 ++++++++++++++++++++++
>  1 file changed, 131 insertions(+)
>  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
>
> diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> new file mode 100644
> index 0000000..f83771b
> --- /dev/null
> +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> @@ -0,0 +1,131 @@
> +// Check if refcount_t type and API should be used
> +// instead of atomic_t type when dealing with refcounters
> +//
> +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> +//
> +// Confidence: Moderate
> +// URL: http://coccinelle.lip6.fr/
> +// Options: --include-headers --very-quiet
> +
> +virtual report
> +
> + at r1 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +(
> + fname at p2(a, ...);
> +|
> + fname2 at p2(...);
> +|
> + fname3 at p2(...);
> +|
> + fname4 at p2(...);
> +|
> + fname5 at p2(...);
> +|
> + fname6 at p2(...);
> +)
> +
> +
> + at script:python depends on report@
> +p1 << r1.p1;
> +p2 << r1.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r4 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +y=a
> +...
> +fname at p2(y, ...);
> +
> +
> + at script:python depends on report@
> +p1 << r4.p1;
> +p2 << r4.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r2 exists@
> +identifier a, x;
> +position p1;
> +@@
> +
> +(
> +atomic_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic_long_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic64_add_unless(&(a)->x,-1,1)@p1
> +)
> +
> + at script:python depends on report@
> +p1 << r2.p1;
> +@@
> +msg = "atomic_add_unless"
> +coccilib.report.print_report(p1[0], msg)
> +
> + at r3 exists@
> +identifier x;
> +position p1;
> +@@
> +
> +(
> +x = atomic_add_return at p1(-1, ...);
> +|
> +x = atomic_long_add_return at p1(-1, ...);
> +|
> +x = atomic64_add_return at p1(-1, ...);
> +)
> +
> + at script:python depends on report@
> +p1 << r3.p1;
> +@@
> +msg = "x = atomic_add_return(-1, ...)"
> +coccilib.report.print_report(p1[0], msg)
> +
> +
> --
> 2.7.4
>
>

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Elena Reshetova]

atomic_as_refcounter.cocci script allows detecting
cases when refcount_t type and API should be used
instead of atomic_t.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
---
 scripts/coccinelle/api/atomic_as_refcounter.cocci | 131 ++++++++++++++++++++++
 1 file changed, 131 insertions(+)
 create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci

diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
new file mode 100644
index 0000000..f83771b
--- /dev/null
+++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
@@ -0,0 +1,131 @@
+// Check if refcount_t type and API should be used
+// instead of atomic_t type when dealing with refcounters
+//
+// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
+//
+// Confidence: Moderate
+// URL: http://coccinelle.lip6.fr/
+// Options: --include-headers --very-quiet
+
+virtual report
+
+ at r1 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+identifier fname2 =~ ".*destroy.*";
+identifier fname3 =~ ".*del.*";
+identifier fname4 =~ ".*queue_work.*";
+identifier fname5 =~ ".*schedule_work.*";
+identifier fname6 =~ ".*call_rcu.*";
+
+@@
+
+(
+ atomic_dec_and_test at p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+(
+ fname at p2(a, ...);
+|
+ fname2 at p2(...);
+|
+ fname3 at p2(...);
+|
+ fname4 at p2(...);
+|
+ fname5 at p2(...);
+|
+ fname6 at p2(...);
+)
+
+
+ at script:python depends on report@
+p1 << r1.p1;
+p2 << r1.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+ at r4 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+
+@@
+
+(
+ atomic_dec_and_test@p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+y=a
+...
+fname at p2(y, ...);
+
+
+ at script:python depends on report@
+p1 << r4.p1;
+p2 << r4.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+@r2 exists@
+identifier a, x;
+position p1;
+@@
+
+(
+atomic_add_unless(&(a)->x,-1,1)@p1
+|
+atomic_long_add_unless(&(a)->x,-1,1)@p1
+|
+atomic64_add_unless(&(a)->x,-1,1)@p1
+)
+
+ at script:python depends on report@
+p1 << r2.p1;
+@@
+msg = "atomic_add_unless"
+coccilib.report.print_report(p1[0], msg)
+
+ at r3 exists@
+identifier x;
+position p1;
+@@
+
+(
+x = atomic_add_return at p1(-1, ...);
+|
+x = atomic_long_add_return at p1(-1, ...);
+|
+x = atomic64_add_return at p1(-1, ...);
+)
+
+@script:python depends on report@
+p1 << r3.p1;
+@@
+msg = "x = atomic_add_return(-1, ...)"
+coccilib.report.print_report(p1[0], msg)
+
+
-- 
2.7.4

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Reshetova, Elena]

> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> 
> Personally, I find the above regular expressions much easier to understand
> than the merged version that Markus proposed.  

I really don't have a strong opinion on the presentation side. 
One is more compact, the above one perhaps a bit clearer for unexperienced reader (like myself). 
Sometimes when I try to read patterns from cocci folder,
it takes me really a while to understand what is happening, which is not the case
with simple expression above. I have just considered myself to be too new into this
and therefore sticked to simple expressions to make sure I am minimizing functional mistakes. 

But the performance issue is
> only on whether to use regular expressions or not.  If you use regular
> expressions, Coccinelle will not do some optimizations.  But once you
> decide to use regular expressions, the performance hit is already taken -
> for a good cause here, to my understanding.  

Ok, so then performance is not even a factor. Thank you for the explanation! 

So just put whatever you find
> convenient, in terms of readability, precision, etc.  It seems that del is
> not very precise, because it is a substring of multiple words with
> different meanings.  Maybe it should be improved, or maybe one can just
> live with the false positives (eg delay), if they actually are false
> positives.

This is the problem that some of them might be and some not. 
I can call the queuing works explicitly:
identifier fname4 =~ ".*queue_work.*";
identifier fname5 =~ ".*queue_delayed_work.*";

Then there is no need to match "delay", but I still like to match both "delete" and "del". 

Best Regards,
Elena.
> 
> julia

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Julia Lawall]

> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";

Personally, I find the above regular expressions much easier to understand
than the merged version that Markus proposed.  But the performance issue is
only on whether to use regular expressions or not.  If you use regular
expressions, Coccinelle will not do some optimizations.  But once you
decide to use regular expressions, the performance hit is already taken -
for a good cause here, to my understanding.  So just put whatever you find
convenient, in terms of readability, precision, etc.  It seems that del is
not very precise, because it is a substring of multiple words with
different meanings.  Maybe it should be improved, or maybe one can just
live with the false positives (eg delay), if they actually are false
positives.

julia

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Elena Reshetova]

atomic_as_refcounter.cocci script allows detecting
cases when refcount_t type and API should be used
instead of atomic_t.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
---
 scripts/coccinelle/api/atomic_as_refcounter.cocci | 133 ++++++++++++++++++++++
 1 file changed, 133 insertions(+)
 create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci

diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
new file mode 100644
index 0000000..64c97d1
--- /dev/null
+++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
@@ -0,0 +1,133 @@
+// Check if refcount_t type and API should be used
+// instead of atomic_t type when dealing with refcounters
+//
+// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
+//
+// Confidence: Moderate
+// URL: http://coccinelle.lip6.fr/
+// Options: --include-headers --very-quiet
+
+virtual report
+
+ at r1 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+identifier fname2 =~ ".*destroy.*";
+identifier fname3 =~ ".*del.*";
+identifier fname4 =~ ".*queue_work.*";
+identifier fname5 =~ ".*schedule_work.*";
+identifier fname6 =~ ".*call_rcu.*";
+
+@@
+
+(
+ atomic_dec_and_test at p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+(
+ fname at p2(a, ...);
+|
+ fname2 at p2(...);
+|
+ fname3 at p2(...);
+|
+ fname4 at p2(...);
+|
+ fname5 at p2(...);
+|
+ fname6 at p2(...);
+)
+
+
+ at script:python depends on report@
+p1 << r1.p1;
+p2 << r1.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+ at r4 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+
+@@
+
+(
+ atomic_dec_and_test@p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+y=a
+...
+(
+ fname at p2(y, ...);
+)
+
+
+ at script:python depends on report@
+p1 << r4.p1;
+p2 << r4.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+@r2 exists@
+identifier a, x;
+position p1;
+@@
+
+(
+atomic_add_unless(&(a)->x,-1,1)@p1
+|
+atomic_long_add_unless(&(a)->x,-1,1)@p1
+|
+atomic64_add_unless(&(a)->x,-1,1)@p1
+)
+
+ at script:python depends on report@
+p1 << r2.p1;
+@@
+msg = "atomic_add_unless"
+coccilib.report.print_report(p1[0], msg)
+
+ at r3 exists@
+identifier x;
+position p1;
+@@
+
+(
+x = atomic_add_return at p1(-1, ...);
+|
+x = atomic_long_add_return at p1(-1, ...);
+|
+x = atomic64_add_return at p1(-1, ...);
+)
+
+@script:python depends on report@
+p1 << r3.p1;
+@@
+msg = "x = atomic_add_return(-1, ...)"
+coccilib.report.print_report(p1[0], msg)
+
+
-- 
2.7.4

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Reshetova, Elena]

> On Mon, 14 Aug 2017, Elena Reshetova wrote:
> 
> > atomic_as_refcounter.cocci script allows detecting
> > cases when refcount_t type and API should be used
> > instead of atomic_t.
> >
> > Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> > ---
> >  scripts/coccinelle/api/atomic_as_refcounter.cocci | 148
> ++++++++++++++++++++++
> >  1 file changed, 148 insertions(+)
> >  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
> >
> > diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci
> b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > new file mode 100644
> > index 0000000..996d72b
> > --- /dev/null
> > +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> > @@ -0,0 +1,148 @@
> > +// Check if refcount_t type and API should be used
> > +// instead of atomic_t type when dealing with refcounters
> > +//
> > +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> > +//
> > +// Confidence: Moderate
> > +// URL: http://coccinelle.lip6.fr/
> > +// Options: --include-headers --very-quiet
> > +
> > +virtual report
> > +
> > + at r1 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +(
> > + fname at p2(a, ...);
> > +|
> > + fname2 at p2(...);
> > +|
> > + fname3 at p2(...);
> > +|
> > + fname4 at p2(...);
> > +|
> > + fname5 at p2(...);
> > +|
> > + fname6 at p2(...);
> > +)
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r1.p1;
> > +p2 << r1.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r4 exists@
> > +identifier a, x, y;
> > +position p1, p2;
> > +identifier fname =~ ".*free.*";
> > +identifier fname2 =~ ".*destroy.*";
> > +identifier fname3 =~ ".*del.*";
> > +identifier fname4 =~ ".*queue_work.*";
> > +identifier fname5 =~ ".*schedule_work.*";
> > +identifier fname6 =~ ".*call_rcu.*";
> > +
> > +@@
> > +
> > +(
> > + atomic_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> > +|
> > + atomic_long_dec_and_test at p1(&(a)->x)
> > +|
> > + atomic64_dec_and_test at p1(&(a)->x)
> > +|
> > + local_dec_and_test at p1(&(a)->x)
> > +)
> > +...
> > +y=a
> > +...
> > +(
> > + fname at p2(y, ...);
> > +|
> > + fname2 at p2(...);
> 
> From here to the end of the rule there is no a or y.  So they would match
> the same thing as in the previous rule.  so you could get rid of all of
> these cases, and just leave fname at p2(y, ...);

True, stupid of me :(
Will fix. 

Best Regards,
Elena.

> 
> julia
> 
> > +|
> > + fname3 at p2(...);
> > +|
> > + fname4 at p2(...);
> > +|
> > + fname5 at p2(...);
> > +|
> > + fname6 at p2(...);
> > +)
> > +
> > +
> > + at script:python depends on report@
> > +p1 << r4.p1;
> > +p2 << r4.p2;
> > +@@
> > +msg = "atomic_dec_and_test variation before object free at line %s."
> > +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> > +
> > + at r2 exists@
> > +identifier a, x;
> > +position p1;
> > +@@
> > +
> > +(
> > +atomic_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic_long_add_unless(&(a)->x,-1,1)@p1
> > +|
> > +atomic64_add_unless(&(a)->x,-1,1)@p1
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r2.p1;
> > +@@
> > +msg = "atomic_add_unless"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > + at r3 exists@
> > +identifier x;
> > +position p1;
> > +@@
> > +
> > +(
> > +x = atomic_add_return at p1(-1, ...);
> > +|
> > +x = atomic_long_add_return at p1(-1, ...);
> > +|
> > +x = atomic64_add_return at p1(-1, ...);
> > +)
> > +
> > + at script:python depends on report@
> > +p1 << r3.p1;
> > +@@
> > +msg = "x = atomic_add_return(-1, ...)"
> > +coccilib.report.print_report(p1[0], msg)
> > +
> > +
> > --
> > 2.7.4
> >
> >

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Julia Lawall]

On Mon, 14 Aug 2017, Elena Reshetova wrote:

> atomic_as_refcounter.cocci script allows detecting
> cases when refcount_t type and API should be used
> instead of atomic_t.
>
> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
> ---
>  scripts/coccinelle/api/atomic_as_refcounter.cocci | 148 ++++++++++++++++++++++
>  1 file changed, 148 insertions(+)
>  create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci
>
> diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> new file mode 100644
> index 0000000..996d72b
> --- /dev/null
> +++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
> @@ -0,0 +1,148 @@
> +// Check if refcount_t type and API should be used
> +// instead of atomic_t type when dealing with refcounters
> +//
> +// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
> +//
> +// Confidence: Moderate
> +// URL: http://coccinelle.lip6.fr/
> +// Options: --include-headers --very-quiet
> +
> +virtual report
> +
> + at r1 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +(
> + fname at p2(a, ...);
> +|
> + fname2 at p2(...);
> +|
> + fname3 at p2(...);
> +|
> + fname4 at p2(...);
> +|
> + fname5 at p2(...);
> +|
> + fname6 at p2(...);
> +)
> +
> +
> + at script:python depends on report@
> +p1 << r1.p1;
> +p2 << r1.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r4 exists@
> +identifier a, x, y;
> +position p1, p2;
> +identifier fname =~ ".*free.*";
> +identifier fname2 =~ ".*destroy.*";
> +identifier fname3 =~ ".*del.*";
> +identifier fname4 =~ ".*queue_work.*";
> +identifier fname5 =~ ".*schedule_work.*";
> +identifier fname6 =~ ".*call_rcu.*";
> +
> +@@
> +
> +(
> + atomic_dec_and_test at p1(&(a)->x)
> +|
> + atomic_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_lock at p1(&(a)->x, ...)
> +|
> + atomic_long_dec_and_test at p1(&(a)->x)
> +|
> + atomic64_dec_and_test at p1(&(a)->x)
> +|
> + local_dec_and_test at p1(&(a)->x)
> +)
> +...
> +y=a
> +...
> +(
> + fname at p2(y, ...);
> +|
> + fname2 at p2(...);

>From here to the end of the rule there is no a or y.  So they would match
the same thing as in the previous rule.  so you could get rid of all of
these cases, and just leave fname at p2(y, ...);

julia

> +|
> + fname3 at p2(...);
> +|
> + fname4 at p2(...);
> +|
> + fname5 at p2(...);
> +|
> + fname6 at p2(...);
> +)
> +
> +
> + at script:python depends on report@
> +p1 << r4.p1;
> +p2 << r4.p2;
> +@@
> +msg = "atomic_dec_and_test variation before object free at line %s."
> +coccilib.report.print_report(p1[0], msg % (p2[0].line))
> +
> + at r2 exists@
> +identifier a, x;
> +position p1;
> +@@
> +
> +(
> +atomic_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic_long_add_unless(&(a)->x,-1,1)@p1
> +|
> +atomic64_add_unless(&(a)->x,-1,1)@p1
> +)
> +
> + at script:python depends on report@
> +p1 << r2.p1;
> +@@
> +msg = "atomic_add_unless"
> +coccilib.report.print_report(p1[0], msg)
> +
> + at r3 exists@
> +identifier x;
> +position p1;
> +@@
> +
> +(
> +x = atomic_add_return at p1(-1, ...);
> +|
> +x = atomic_long_add_return at p1(-1, ...);
> +|
> +x = atomic64_add_return at p1(-1, ...);
> +)
> +
> + at script:python depends on report@
> +p1 << r3.p1;
> +@@
> +msg = "x = atomic_add_return(-1, ...)"
> +coccilib.report.print_report(p1[0], msg)
> +
> +
> --
> 2.7.4
>
>

[Cocci] [PATCH] Coccinelle: add atomic_as_refcounter script

[Elena Reshetova]

atomic_as_refcounter.cocci script allows detecting
cases when refcount_t type and API should be used
instead of atomic_t.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
---
 scripts/coccinelle/api/atomic_as_refcounter.cocci | 148 ++++++++++++++++++++++
 1 file changed, 148 insertions(+)
 create mode 100644 scripts/coccinelle/api/atomic_as_refcounter.cocci

diff --git a/scripts/coccinelle/api/atomic_as_refcounter.cocci b/scripts/coccinelle/api/atomic_as_refcounter.cocci
new file mode 100644
index 0000000..996d72b
--- /dev/null
+++ b/scripts/coccinelle/api/atomic_as_refcounter.cocci
@@ -0,0 +1,148 @@
+// Check if refcount_t type and API should be used
+// instead of atomic_t type when dealing with refcounters
+//
+// Copyright (c) 2016-2017, Elena Reshetova, Intel Corporation
+//
+// Confidence: Moderate
+// URL: http://coccinelle.lip6.fr/
+// Options: --include-headers --very-quiet
+
+virtual report
+
+ at r1 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+identifier fname2 =~ ".*destroy.*";
+identifier fname3 =~ ".*del.*";
+identifier fname4 =~ ".*queue_work.*";
+identifier fname5 =~ ".*schedule_work.*";
+identifier fname6 =~ ".*call_rcu.*";
+
+@@
+
+(
+ atomic_dec_and_test at p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+(
+ fname at p2(a, ...);
+|
+ fname2 at p2(...);
+|
+ fname3 at p2(...);
+|
+ fname4 at p2(...);
+|
+ fname5 at p2(...);
+|
+ fname6 at p2(...);
+)
+
+
+ at script:python depends on report@
+p1 << r1.p1;
+p2 << r1.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+ at r4 exists@
+identifier a, x, y;
+position p1, p2;
+identifier fname =~ ".*free.*";
+identifier fname2 =~ ".*destroy.*";
+identifier fname3 =~ ".*del.*";
+identifier fname4 =~ ".*queue_work.*";
+identifier fname5 =~ ".*schedule_work.*";
+identifier fname6 =~ ".*call_rcu.*";
+
+@@
+
+(
+ atomic_dec_and_test@p1(&(a)->x)
+|
+ atomic_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_lock at p1(&(a)->x, ...)
+|
+ atomic_long_dec_and_test at p1(&(a)->x)
+|
+ atomic64_dec_and_test at p1(&(a)->x)
+|
+ local_dec_and_test at p1(&(a)->x)
+)
+...
+y=a
+...
+(
+ fname at p2(y, ...);
+|
+ fname2 at p2(...);
+|
+ fname3 at p2(...);
+|
+ fname4 at p2(...);
+|
+ fname5 at p2(...);
+|
+ fname6 at p2(...);
+)
+
+
+ at script:python depends on report@
+p1 << r4.p1;
+p2 << r4.p2;
+@@
+msg = "atomic_dec_and_test variation before object free at line %s."
+coccilib.report.print_report(p1[0], msg % (p2[0].line))
+
+@r2 exists@
+identifier a, x;
+position p1;
+@@
+
+(
+atomic_add_unless(&(a)->x,-1,1)@p1
+|
+atomic_long_add_unless(&(a)->x,-1,1)@p1
+|
+atomic64_add_unless(&(a)->x,-1,1)@p1
+)
+
+ at script:python depends on report@
+p1 << r2.p1;
+@@
+msg = "atomic_add_unless"
+coccilib.report.print_report(p1[0], msg)
+
+ at r3 exists@
+identifier x;
+position p1;
+@@
+
+(
+x = atomic_add_return at p1(-1, ...);
+|
+x = atomic_long_add_return at p1(-1, ...);
+|
+x = atomic64_add_return at p1(-1, ...);
+)
+
+@script:python depends on report@
+p1 << r3.p1;
+@@
+msg = "x = atomic_add_return(-1, ...)"
+coccilib.report.print_report(p1[0], msg)
+
+
-- 
2.7.4