From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793829708; b=SLcLYjcQu/LQluBs0VCZZ8v3++5mTjQYp+WhIj2zwgIw21VolqySJEqNMq72QsoPPl84 v+CLX8RXCHJ/WyVN0Fz6gyDFSqTt5V+wOf4+oVF2s8ZkpG9mCjPWEL3ZdkhsInqYBxETX kfVBeUrE0G+82bwlCr165HnpXxsQBYlTI8Rpk2zO5mYE64h79jURhbh7gD1JLY7IvysWy n/B5wHuyts9WmIV3DDVXE2hqI529f35J2RbMlAhTcNPfEXoOwBhaUu5Y1+E6v41H2rxMB UnR1rWGIBX5rvZ8uX/UzwNScsI6EGk/moFU9lH07XL/T6os3jrfyJZk35/egW0tunJw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793829708; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=KL6MZakt0hQOonDU0X5JnT8kBiGg5Qr5u0I5yGAQfG8=; b=UILIfro36ivyLf6TSQmP5zDZHSSHGbVJHyBgSc2SKhrt+jPNwOP008ZWpLy+/sxcGmOj tv8bcJr56C1za9z8uKxZM6Ta3alVeXRtM2zuAES1CcCuBaEsAijIlkwEpz2jDA6aUIe4H PMz1ai/1a5FMqqzavMxNm0A9LWv0N/whLS6EBFgwlkljbraY++Uwtu6TXbTKrraEMONqm QqriwX+hc5Nh4/BMfEdfuxS1W/c36SimD6oFQOA02MxsZ20uSzZWb8ZdN+pTks3DSq4fF AKXuuaOBfjH4Ba3ti82kfTTf9upH29SSn7Qp1qWxTg08jSO7Zin6QsK+bySu0EQ8DPQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=frwF0i1e; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 244DC606C5A3; Wed, 4 Nov 2026 22:01:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=frwF0i1e Received: by smtp.kernel.org (Postfix) with ESMTPSA id B3D6E1F00919; Wed, 4 Nov 2026 22:01:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793829708; bh=KL6MZakt0hQOonDU0X5JnT8kBiGg5Qr5u0I5yGAQfG8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=frwF0i1eWvfRI5cys51ySOsjISZZH9VdUtsJ8NDVukPa9wgxz0dZZ0wYfwB3BN00c VG8iFP+UDQGhcGF5Bom24c129F3POhVFB/wd1CozYNAQBDYXzliEFEiptHPq7LcqT6 fNQIeTR5ktUiqly6AcETiz9cd/NmUxtUHulTLk54= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Rosen Penev , Srinivas Kandagatla , Sasha Levin Subject: [PATCH 6.18 0292/1005] nvmem: brcm_nvram: reject empty NVRAM partition Date: Wed, 4 Nov 2026 16:00:25 -0500 Message-ID: <20261104211052.092478527@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rosen Penev [ Upstream commit fde46579cf8872138b296349c2bd8a3cd3f132e2 ] If the partition is completely erased (all padding bytes), the trimming loop reduces data_len to 0. devm_kzalloc(dev, 0, GFP_KERNEL) returns ZERO_SIZE_PTR ((void *)16), which is non-NULL and bypasses the NULL check. The subsequent cast of priv->data to struct brcm_nvram_header * and dereference of header->magic causes a page fault on address 0x10. Reject data_len smaller than the header before allocating. Assisted-by: opencode:big-pickle Signed-off-by: Rosen Penev Signed-off-by: Srinivas Kandagatla Link: https://patch.msgid.link/20260729094647.111468-13-srini@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/nvmem/brcm_nvram.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/nvmem/brcm_nvram.c b/drivers/nvmem/brcm_nvram.c index b4cf245fb2467..4b3781a70222a 100644 --- a/drivers/nvmem/brcm_nvram.c +++ b/drivers/nvmem/brcm_nvram.c @@ -84,6 +84,11 @@ static int brcm_nvram_copy_data(struct brcm_nvram *priv, struct platform_device } WARN(priv->data_len > SZ_128K, "Unexpected (big) NVRAM size: %zu B\n", priv->data_len); + if (priv->data_len < sizeof(struct brcm_nvram_header)) { + dev_err(priv->dev, "NVRAM data too small (%zu)\n", priv->data_len); + return -EINVAL; + } + priv->data = devm_kzalloc(priv->dev, priv->data_len, GFP_KERNEL); if (!priv->data) return -ENOMEM; -- 2.53.0