[PATCH v3] Coccinelle: Script to replace NULL test with IS_ERR test for devm_ioremap_resource

[PATCH v3] Coccinelle: Script to replace NULL test with IS_ERR test for devm_ioremap_resource

[Amitoj Kaur Chawla]

This script detects cases which have incorrect error handling for
devm_ioremap_resource function, employing a NULL test instead of an
IS_ERR() test.

Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Amitoj Kaur Chawla <amitoj1606@gmail.com>
---
Changes in v2:
        -Changed script to correct error handling instead of just
         detecting cases of incorrect error handling
Changes in v3:
        -Reverted to original script in v1 to ensure no error in
         modifying inconsistent paths.

 .../null/devm_ioremap_resource_test.cocci          | 38 ++++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100644 scripts/coccinelle/null/devm_ioremap_resource_test.cocci

diff --git a/scripts/coccinelle/null/devm_ioremap_resource_test.cocci b/scripts/coccinelle/null/devm_ioremap_resource_test.cocci
new file mode 100644
index 0000000..734dbd3
--- /dev/null
+++ b/scripts/coccinelle/null/devm_ioremap_resource_test.cocci
@@ -0,0 +1,38 @@
+/// Correct error handling for devm_ioremap_resource
+///
+// Confidence: High
+// Copyright: (C) 2016 Amitoj Kaur Chawla
+// Keywords: devm,devm_ioremap_resource
+
+virtual context
+virtual org
+virtual report
+
+// ----------------------------------------------------------------------------
+
+@err depends on context || org || report@
+statement S;
+expression e;
+position j0;
+@@
+
+  e = devm_ioremap_resource(...);
+* if (!e@j0) S
+// ----------------------------------------------------------------------------
+
+@script:python err_org depends on org@
+j0 << err.j0;
+@@
+
+msg = "Incorrect error handling."
+coccilib.org.print_todo(j0[0], msg)
+
+// ----------------------------------------------------------------------------
+
+@script:python err_report depends on report@
+j0 << err.j0;
+@@
+
+msg = "Incorrect error handling."
+coccilib.report.print_report(j0[0], msg)
+
-- 
1.9.1

Re: [PATCH v3] Coccinelle: Script to replace NULL test with IS_ERR test for devm_ioremap_resource

[SF Markus Elfring]

> +@err depends on context || org || report@
> +statement S;
> +expression e;
> +position j0;

How do you think about to omit the number from this variable name?


> +@@
> +
> +  e = devm_ioremap_resource(...);
> +* if (!e@j0) S

Are there any more functions to consider for such a source code search pattern?
How do you think about to use a function name list here?


> +// ----------------------------------------------------------------------------

I suggest to omit such comment lines from this SmPL script.

Regards,
Markus

Re: [PATCH v3] Coccinelle: Script to replace NULL test with IS_ERR test for devm_ioremap_resource

[Julia Lawall]

On Sat, 6 Aug 2016, SF Markus Elfring wrote:

> > +@err depends on context || org || report@
> > +statement S;
> > +expression e;
> > +position j0;
>
> How do you think about to omit the number from this variable name?
>
>
> > +@@
> > +
> > +  e = devm_ioremap_resource(...);
> > +* if (!e@j0) S
>
> Are there any more functions to consider for such a source code search pattern?
> How do you think about to use a function name list here?

How about getting this into the kernel, and then one can worry about
adding more functions later.

>
> > +// ----------------------------------------------------------------------------
>
> I suggest to omit such comment lines from this SmPL script.

These are introduced by spgen.  Likewise for the numbers on the j
variables.  The pattern j + number can even be useful, because it shows a
position variable that introduced to manage the different kinds of output,
rather than something that is intrinsic to the computation being
performed.

julia

>
> Regards,
> Markus
>