From: Julia Lawall <Julia.Lawall@xxxxxxx> From: Julia Lawall <Julia.Lawall@xxxxxxx> 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@xxxxxxx> --- resend to fix email address diff --git a/scripts/coccinelle/free/devm_free.cocci b/scripts/coccinelle/free/devm_free.cocci new file mode 100644 index 0000000..c0cd3e2 --- /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) + -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
