From: Konstantin Khlebnikov Subject: [PATCH 1/2 v2] scripts/coccinelle: catch freeing cryptographic structures via kfree Date: Tue, 18 Nov 2014 14:50:03 +0400 Message-ID: <20141118114920.13498.73584.stgit@buzz> References: <20141117151420.10739.16342.stgit@buzz> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: Michal Marek , Herbert Xu , Gilles Muller , Nicolas Palix , Julia Lawall , linux-crypto@vger.kernel.org, "David S. Miller" To: kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Eric Biederman Return-path: In-reply-to: <20141117151420.10739.16342.stgit@buzz> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org Structures allocated by crypto_alloc_* must be freed using crypto_free_*. Signed-off-by: Konstantin Khlebnikov --- scripts/coccinelle/free/crypto_free.cocci | 64 +++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) create mode 100644 scripts/coccinelle/free/crypto_free.cocci diff --git a/scripts/coccinelle/free/crypto_free.cocci b/scripts/coccinelle/free/crypto_free.cocci new file mode 100644 index 0000000..a717070 --- /dev/null +++ b/scripts/coccinelle/free/crypto_free.cocci @@ -0,0 +1,64 @@ +/// +/// Structures allocated by crypto_alloc_* must be freed using crypto_free_*. +/// This finds freeing them by kfree. +/// +// Confidence: Moderate +// Copyright: (C) 2014 Konstantin Khlebnikov, GPLv2. +// Comments: There are false positives in crypto/ where they are actually freed. +// Keywords: crypto, kfree +// Options: --no-includes --include-headers + +virtual org +virtual report +virtual context + +@r depends on context || org || report@ +expression x; +@@ + +( + x = crypto_alloc_base(...) +| + x = crypto_alloc_cipher(...) +| + x = crypto_alloc_ablkcipher(...) +| + x = crypto_alloc_aead(...) +| + x = crypto_alloc_instance(...) +| + x = crypto_alloc_instance2(...) +| + x = crypto_alloc_comp(...) +| + x = crypto_alloc_pcomp(...) +| + x = crypto_alloc_hash(...) +| + x = crypto_alloc_ahash(...) +| + x = crypto_alloc_shash(...) +| + x = crypto_alloc_rng(...) +) + +@pb@ +expression r.x; +position p; +@@ + +* kfree@p(x) + +@script:python depends on org@ +p << pb.p; +@@ + +msg="WARNING: invalid free of crypto_alloc_* allocated data" +coccilib.org.print_todo(p[0], msg) + +@script:python depends on report@ +p << pb.p; +@@ + +msg="WARNING: invalid free of crypto_alloc_* allocated data" +coccilib.report.print_report(p[0], msg)