From nobody Mon Jun 15 00:04:35 2026 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6AD493750AC for ; Tue, 7 Apr 2026 03:53:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775534026; cv=none; b=tmSr+h7v7tvR6jdoSz2IMIAbbdutor4Xmvm1EFJ9OCUgPYKiqtDGEAZYXWJOTlGrySVL55lOo5JTqdPVRqcRu/+e7evwdPY1E7dghSNsZANjywrHP+T3RG5a28Z1cf/JD7kGM1JEUJi7Vf4hdhUEtedyiS0IYAPnd9RGtHmi6P8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775534026; c=relaxed/simple; bh=TfahA/wsrkvwkmZc2KR//z9W5cA4klo1I345lE+Wi74=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Hd/lqkxqhYZfRS118l6YZA7GLq6UvDsmd1yYNQhxFP4nw2cg64Znev8KHoW51q6HIEQyGgFcZDZ8SeCndI56y48MnEwJmuyq/2SWSZy6pGevMC9a8sT589RpCow28jdQNVRWksK2UXxLVgJK3HzNliZ56IPKMIo83bVwmi51d94= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn; spf=pass smtp.mailfrom=iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=iscas.ac.cn Received: from dfae2b116770.home.arpa (unknown [124.16.138.129]) by APP-05 (Coremail) with SMTP id zQCowAC3TBC3f9Rp0gfGDA--.5424S2; Tue, 07 Apr 2026 11:53:28 +0800 (CST) From: Wentao Liang To: Peter Rosin Cc: Thorsten Blum , Kees Cook , linux-kernel@vger.kernel.org, Wentao Liang Subject: [PATCH] mux: fix use-after-free and node leak in mux_get() Date: Tue, 7 Apr 2026 03:53:06 +0000 Message-Id: <20260407035306.243905-1-vulab@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: zQCowAC3TBC3f9Rp0gfGDA--.5424S2 X-Coremail-Antispam: 1UD129KBjvJXoW7Cr4DuF13uF4xJF13Kw48WFg_yoW8tw4xpF WUXay3ZF1fGF4fJF1Fvr1UW3W3tF4fKayfJ393Gw1I9wnxJ34UAryjgr9Y9w45CFy8X34D Ar48t3W8CF40yr7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvq14x267AKxVWUJVW8JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26ryj6F1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY1x0262kKe7AKxVWU AVWUtwCY02Avz4vE14v_Gr4l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr 1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE 14v26r126r1DMIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7 IYx2IY6xkF7I0E14v26r1j6r4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E 87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r1j6r4UYxBIdaVFxhVjvjDU0x ZFpf9x0JUoKZXUUUUU= X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiDAYKA2nUV4a4HwAAsI Content-Type: text/plain; charset="utf-8" In mux_get(), after obtaining args.np via of_parse_phandle_with_args(), of_node_put(args.np) was called immediately. However, args.np is still used in error paths for dev_err() printing. This leads to a use-after- free when those error branches are taken. Fix both issues by moving of_node_put(args.np) after all usage of args.np, and introducing a common error label "put_and_ret_err" to centralize node release. Also add missing of_node_put() in all error path. Fixes: 84564481bc45 ("mux: Add support for reading mux state from consumer = DT node") Signed-off-by: Wentao Liang --- drivers/mux/core.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) diff --git a/drivers/mux/core.c b/drivers/mux/core.c index a3840fe0995f..517ad3075196 100644 --- a/drivers/mux/core.c +++ b/drivers/mux/core.c @@ -564,9 +564,10 @@ static struct mux_control *mux_get(struct device *dev,= const char *mux_name, } =20 mux_chip =3D of_find_mux_chip_by_node(args.np); - of_node_put(args.np); - if (!mux_chip) - return ERR_PTR(-EPROBE_DEFER); + if (!mux_chip) { + ret =3D -EPROBE_DEFER; + goto put_and_ret_err; + } =20 controller =3D 0; if (state) { @@ -575,7 +576,8 @@ static struct mux_control *mux_get(struct device *dev, = const char *mux_name, dev_err(dev, "%pOF: wrong #mux-state-cells for %pOF\n", np, args.np); put_device(&mux_chip->dev); - return ERR_PTR(-EINVAL); + ret =3D -EINVAL; + goto put_and_ret_err; } =20 if (args.args_count =3D=3D 2) { @@ -591,7 +593,8 @@ static struct mux_control *mux_get(struct device *dev, = const char *mux_name, dev_err(dev, "%pOF: wrong #mux-control-cells for %pOF\n", np, args.np); put_device(&mux_chip->dev); - return ERR_PTR(-EINVAL); + ret =3D -EINVAL; + goto put_and_ret_err; } =20 if (args.args_count) @@ -602,10 +605,16 @@ static struct mux_control *mux_get(struct device *dev= , const char *mux_name, dev_err(dev, "%pOF: bad mux controller %u specified in %pOF\n", np, controller, args.np); put_device(&mux_chip->dev); - return ERR_PTR(-EINVAL); + ret =3D -EINVAL; + goto put_and_ret_err; } =20 + of_node_put(args.np); return &mux_chip->mux[controller]; + +put_and_ret_err: + of_node_put(args.np); + return ERR_PTR(ret); } =20 /** --=20 2.34.1