Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752344AbdLDPry (ORCPT ); Mon, 4 Dec 2017 10:47:54 -0500 Received: from albert.telenet-ops.be ([195.130.137.90]:39568 "EHLO albert.telenet-ops.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751821AbdLDPrn (ORCPT ); Mon, 4 Dec 2017 10:47:43 -0500 From: Geert Uytterhoeven To: Pantelis Antoniou , Rob Herring , Frank Rowand Cc: Colin King , Dan Carpenter , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Geert Uytterhoeven Subject: [PATCH v2 1/2] of: overlay: Fix memory leak in of_overlay_apply() error path Date: Mon, 4 Dec 2017 16:47:35 +0100 Message-Id: <1512402456-8176-2-git-send-email-geert+renesas@glider.be> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1512402456-8176-1-git-send-email-geert+renesas@glider.be> References: <1512402456-8176-1-git-send-email-geert+renesas@glider.be> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1508 Lines: 42 If of_resolve_phandles() fails, free_overlay_changeset() is called in the error path. However, that function returns early if the list hasn't been initialized yet, before freeing the object. Explicitly calling kfree() instead would solve that issue. However, that complicates matter, by having to consider which of two different methods to use to dispose of the same object. Hence make free_overlay_changeset() consider initialization state of the different parts of the object, making it always safe to call (once!) to dispose of a (partially) initialized overlay_changeset: - Only destroy the changeset if the list was initialized, - Ignore uninitialized IDs (zero). Reported-by: Colin King Fixes: f948d6d8b792bb90 ("of: overlay: avoid race condition between applying multiple overlays") Signed-off-by: Geert Uytterhoeven --- drivers/of/overlay.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/of/overlay.c b/drivers/of/overlay.c index 3b7a3980ff50d6bf..312cd658bec0083b 100644 --- a/drivers/of/overlay.c +++ b/drivers/of/overlay.c @@ -630,11 +630,10 @@ static void free_overlay_changeset(struct overlay_changeset *ovcs) { int i; - if (!ovcs->cset.entries.next) - return; - of_changeset_destroy(&ovcs->cset); + if (ovcs->cset.entries.next) + of_changeset_destroy(&ovcs->cset); - if (ovcs->id) + if (ovcs->id > 0) idr_remove(&ovcs_idr, ovcs->id); for (i = 0; i < ovcs->count; i++) { -- 2.7.4