From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5204E1F76AD; Tue, 3 Dec 2024 16:11:05 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733242265; cv=none; b=BvRXYJ76tPJiHN2jKVlRZdnWhe6Li1Nfaxm6K5rEFuNHez27yXpKxF2OBnB3Nm7icHqAGcT4AuND92ZTc2SYB7mIuJfMYX2t9NC5Hu0+kjgEanUyM0Vp1MTRzWZYSyygNcBEI5CkOj7uoyBNhbghX/05HerjbC3LURxfbemmxTU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1733242265; c=relaxed/simple; bh=R0MAHwOaYNnGV1q9W4oHRq5TPT9/SGTShumxk3K9pD4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=u/v47oO3dtvbMHUy3vu0tpZToNc1Ky0Rgox4nWnRISO4eSLKUTR4t7+hyd2nJ4/6FibT4UGxIL0MpHgi94N/DT5atOqRWX7HzfPOKc9/xYqJPU/HqnH4zRPMoPDTo2smzTgY3jOYb3fJ79DYTn1mPz4hoKmgtMXA0HgDbc7fHMM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TF/zOxki; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="TF/zOxki" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BA74BC4CECF; Tue, 3 Dec 2024 16:11:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1733242265; bh=R0MAHwOaYNnGV1q9W4oHRq5TPT9/SGTShumxk3K9pD4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TF/zOxkiKkCqK8EuGe2J6gDmUO/u6+LRmQkFRKgequUAH5K06Ox/IlMh7bB9eu8VY ujU5ChNa7jQ5oCntNM+q1J52SllfG0QzmVbkhpmXd0tTUgkQ/0Hhy3sfGphkMTzxti +JFOlUPS1fTKzrfA6iBw2DvsxC5SQ8T4TyG30bPQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Gustavo A. R. Silva" , Stephen Boyd Subject: [PATCH 6.12 656/826] clk: clk-loongson2: Fix memory corruption bug in struct loongson2_clk_provider Date: Tue, 3 Dec 2024 15:46:23 +0100 Message-ID: <20241203144809.344093107@linuxfoundation.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241203144743.428732212@linuxfoundation.org> References: <20241203144743.428732212@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit 6e4bf018bb040955da53dae9f8628ef8fcec2dbe upstream. Some heap space is allocated for the flexible structure `struct clk_hw_onecell_data` and its flexible-array member `hws` through the composite structure `struct loongson2_clk_provider` in function `loongson2_clk_probe()`, as shown below: 289 struct loongson2_clk_provider *clp; ... 296 for (p = data; p->name; p++) 297 clks_num++; 298 299 clp = devm_kzalloc(dev, struct_size(clp, clk_data.hws, clks_num), 300 GFP_KERNEL); Then some data is written into the flexible array: 350 clp->clk_data.hws[p->id] = hw; This corrupts `clk_lock`, which is the spinlock variable immediately following the `clk_data` member in `struct loongson2_clk_provider`: struct loongson2_clk_provider { void __iomem *base; struct device *dev; struct clk_hw_onecell_data clk_data; spinlock_t clk_lock; /* protect access to DIV registers */ }; The problem is that the flexible structure is currently placed in the middle of `struct loongson2_clk_provider` instead of at the end. Fix this by moving `struct clk_hw_onecell_data clk_data;` to the end of `struct loongson2_clk_provider`. Also, add a code comment to help prevent this from happening again in case new members are added to the structure in the future. This change also fixes the following -Wflex-array-member-not-at-end warning: drivers/clk/clk-loongson2.c:32:36: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end] Fixes: 9796ec0bd04b ("clk: clk-loongson2: Refactor driver for adding new platforms") Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Link: https://lore.kernel.org/r/ZzZ-cd_EFXs6qFaH@kspp Signed-off-by: Stephen Boyd Signed-off-by: Greg Kroah-Hartman --- drivers/clk/clk-loongson2.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/clk/clk-loongson2.c +++ b/drivers/clk/clk-loongson2.c @@ -29,8 +29,10 @@ enum loongson2_clk_type { struct loongson2_clk_provider { void __iomem *base; struct device *dev; - struct clk_hw_onecell_data clk_data; spinlock_t clk_lock; /* protect access to DIV registers */ + + /* Must be last --ends in a flexible-array member. */ + struct clk_hw_onecell_data clk_data; }; struct loongson2_clk_data {