From nobody Sun Feb 8 23:32:59 2026 Received: from zg8tmtu5ljg5lje1ms4xmtka.icoremail.net (zg8tmtu5ljg5lje1ms4xmtka.icoremail.net [159.89.151.119]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 95ADF1FA3; Thu, 29 Feb 2024 12:23:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.89.151.119 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709209403; cv=none; b=g1INh+KN79+oRDQEAOTuFvypDU3bKSuVX+Kxvt94Kaj5FiL2H7erJ8fzhoQ33kNZUUzNYwF/bNeItSdyB6SfoAm+Zwapds5U0QBIE2AAO9ml7i4zbnEKma/t3XEx+1SMchK1DkhZKa6z180azGKR56zWH99i98i8AcICS7jqrCo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709209403; c=relaxed/simple; bh=9bw/tOBzuEyt2UgNj6zGFgbsv+CXBbuZyMtRZjhVKOo=; h=From:To:Cc:Subject:Date:Message-Id; b=CfIY7rytnW+w7SQdcswZG4d0CsZseydDTv720BjceV11cZPOmeh8bmZE3KnjiqUJAmCobRR7MU70CVftpEaciC0jNFaclixxzXhDz1PmdgLgSHlxHpqA8vfz5bRrj+mxByR5whTT3uYWYbUDx0Qne26ametgesSwX73fE7Y+dBA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=zju.edu.cn; spf=pass smtp.mailfrom=zju.edu.cn; arc=none smtp.client-ip=159.89.151.119 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=zju.edu.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zju.edu.cn Received: from ubuntu.localdomain (unknown [218.12.19.137]) by mail-app2 (Coremail) with SMTP id by_KCgB3uKcbd+BlOY1oAg--.37484S2; Thu, 29 Feb 2024 20:23:00 +0800 (CST) From: Duoming Zhou To: linux-kernel@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org, michal.simek@amd.com, sboyd@kernel.org, mturquette@baylibre.com, Duoming Zhou Subject: [PATCH v2] clk: zynq: Prevent null pointer dereference caused by kmalloc failure Date: Thu, 29 Feb 2024 20:22:50 +0800 Message-Id: <20240229122250.24786-1-duoming@zju.edu.cn> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: by_KCgB3uKcbd+BlOY1oAg--.37484S2 X-Coremail-Antispam: 1UD129KBjvJXoWrtw1fCr1xCFW3XF1fKFy3urg_yoW8JF1xpF WxWrn0yF4DWr4qgFZrCFyxZrWS9ay7Wa42g34Iq34vvrn8JFWUWFW5CF95ZF18XrWfWFW3 tF4Utr48W3WUC3JanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUkC14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_JrI_JrylYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lc7CjxVAaw2AFwI0_ JF0_Jw1l42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67 AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIY rxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14 v26r1j6r4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8 JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUr2-eDU UUU X-CM-SenderInfo: qssqjiasttq6lmxovvfxof0/1tbiAwIGAWXfgNMODgAmsJ Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" The kmalloc() in zynq_clk_setup() will return null if the physical memory has run out. As a result, if we use snprintf to write data to the null address, the null pointer dereference bug will happen. This patch adds a stack variable to replace the kmalloc(). Fixes: 0ee52b157b8e ("clk: zynq: Add clock controller driver") Signed-off-by: Duoming Zhou --- Changes in v2: - Use stack variable to replace kmalloc(). drivers/clk/zynq/clkc.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/clk/zynq/clkc.c b/drivers/clk/zynq/clkc.c index 7bdeaff2bfd..e4c4c9adf79 100644 --- a/drivers/clk/zynq/clkc.c +++ b/drivers/clk/zynq/clkc.c @@ -427,7 +427,7 @@ static void __init zynq_clk_setup(struct device_node *n= p) SLCR_GEM1_CLK_CTRL, 0, 0, &gem1clk_lock); =20 tmp =3D strlen("mio_clk_00x"); - clk_name =3D kmalloc(tmp, GFP_KERNEL); + char clk_name[tmp]; for (i =3D 0; i < NUM_MIO_PINS; i++) { int idx; =20 @@ -439,7 +439,6 @@ static void __init zynq_clk_setup(struct device_node *n= p) else can_mio_mux_parents[i] =3D dummy_nm; } - kfree(clk_name); clk_register_mux(NULL, "can_mux", periph_parents, 4, CLK_SET_RATE_NO_REPARENT, SLCR_CAN_CLK_CTRL, 4, 2, 0, &canclk_lock); --=20 2.17.1