aboutsummaryrefslogtreecommitdiff
path: root/scripts
diff options
context:
space:
mode:
authorJulia Lawall <Julia.Lawall@lip6.fr>2011-12-27 18:28:51 +0100
committerMichal Marek <mmarek@suse.cz>2012-01-14 22:40:04 +0100
commitfb3f8af4ff52faf9b31e6c4e8ca0b0b16332808c (patch)
tree41aa64830b16a74300c0d6dd5f1323b373c86655 /scripts
parent22e0059af301ec163d563c3590d2277c2a557d4f (diff)
downloadlinux-linaro-stable-fb3f8af4ff52faf9b31e6c4e8ca0b0b16332808c.tar.gz
coccinelle: semantic patches related to devm_ functions (part 2)
devm_ functions allocate memory that is to remain allocated until the device is detached. This patch checks for freeing of such memory using standard memory freeing functions. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Michal Marek <mmarek@suse.cz>
Diffstat (limited to 'scripts')
-rw-r--r--scripts/coccinelle/free/devm_free.cocci71
1 files changed, 71 insertions, 0 deletions
diff --git a/scripts/coccinelle/free/devm_free.cocci b/scripts/coccinelle/free/devm_free.cocci
new file mode 100644
index 000000000000..0a1e36146d76
--- /dev/null
+++ b/scripts/coccinelle/free/devm_free.cocci
@@ -0,0 +1,71 @@
+/// Find uses of standard freeing functons on values allocated using devm_
+/// functions. Values allocated using the devm_functions are freed when
+/// the device is detached, and thus the use of the standard freeing
+/// function would cause a double free.
+/// See Documentation/driver-model/devres.txt for more information.
+///
+/// A difficulty of detecting this problem is that the standard freeing
+/// function might be called from a different function than the one
+/// containing the allocation function. It is thus necessary to make the
+/// connection between the allocation function and the freeing function.
+/// Here this is done using the specific argument text, which is prone to
+/// false positives. There is no rule for the request_region and
+/// request_mem_region variants because this heuristic seems to be a bit
+/// less reliable in these cases.
+///
+// Confidence: Moderate
+// Copyright: (C) 2011 Julia Lawall, INRIA/LIP6. GPLv2.
+// Copyright: (C) 2011 Gilles Muller, INRIA/LiP6. GPLv2.
+// URL: http://coccinelle.lip6.fr/
+// Comments:
+// Options: -no_includes -include_headers
+
+virtual org
+virtual report
+virtual context
+
+@r depends on context || org || report@
+expression x;
+@@
+
+(
+ x = devm_kzalloc(...)
+|
+ x = devm_request_irq(...)
+|
+ x = devm_ioremap(...)
+|
+ x = devm_ioremap_nocache(...)
+|
+ x = devm_ioport_map(...)
+)
+
+@pb@
+expression r.x;
+position p;
+@@
+
+(
+* kfree@p(x)
+|
+* free_irq@p(x)
+|
+* iounmap@p(x)
+|
+* ioport_unmap@p(x)
+)
+
+@script:python depends on org@
+p << pb.p;
+@@
+
+msg="WARNING: invalid free of devm_ allocated data"
+coccilib.org.print_todo(p[0], msg)
+
+@script:python depends on report@
+p << pb.p;
+@@
+
+msg="WARNING: invalid free of devm_ allocated data"
+coccilib.report.print_report(p[0], msg)
+