From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 A01C23368B6; Wed, 20 May 2026 18:15:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300957; cv=none; b=GQO6PML6YqCT7hnLkrkCbuJHPBhvGaHQoeIYj3cFQsM0/n2Fn5QxMSlCnE7M/dYjUa+rBrk5zwPPVGvS4G/BoxjIRMigggM/Olhd3or8jJTEmDkwahbn/iMcqjYlwYLQl4vP8TPz3HwP/0c1FJG4KlDm0BNALMIabtcYQuA8D1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300957; c=relaxed/simple; bh=dfS5NYYpXiyL7Q4kSg9zCIstm41PDkpLI6mzHj6qfyM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=fzkgmVjjXj2UYEU0ZkA6GwN8LwQfi6p2UyetJfWPFYxF6IiPIBRPZZrrYnxZDVXFSNTmXILhDZqYYj/ldK9ihScZ2L4YRxJ+S8kv9i5rj3eEOPn3oQxCO5FhP/le7MeVXZpC9WW5G9g0PEznC8DPlzT42QMfxQm/2F57o/Hj8kA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=A9VjTwc0; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="A9VjTwc0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 110B51F000E9; Wed, 20 May 2026 18:15:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779300956; bh=Hxfs8w/EZ+L4PRE3OEWcdGv0SFOujIWLt76wIMqEtBA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=A9VjTwc0CqQPboT6N4duXEviY1ECTFdi3Gvywh1gb/rcH5Qm+sX6TBsUeHt17diw4 3T+i2B1DPP/Q7VjJFjEVfg5YU78u3vp5JoMI+jYSSkGuqUYOfF1th6RYHHhPXIMtM3 y0Gsoiv6Aco5MU2LauHoUL5SuUarBJO4RY8kXYrw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jian Zhang , Corey Minyard , Sasha Levin Subject: [PATCH 6.12 371/666] ipmi: ssif_bmc: fix missing check for copy_to_user() partial failure Date: Wed, 20 May 2026 18:19:42 +0200 Message-ID: <20260520162119.284132357@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162111.222830634@linuxfoundation.org> References: <20260520162111.222830634@linuxfoundation.org> User-Agent: quilt/0.69 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: Jian Zhang [ Upstream commit ea641be7a4faee4351f9c5ed6b188e1bbf5586a6 ] copy_to_user() returns the number of bytes that could not be copied, with a non-zero value indicating a partial or complete failure. The current code only checks for negative return values and treats all non-negative results as success. Treating any positive return value from copy_to_user() as an error and returning -EFAULT. Fixes: dd2bc5cc9e25 ("ipmi: ssif_bmc: Add SSIF BMC driver") Signed-off-by: Jian Zhang Message-ID: <20260403090603.3988423-2-zhangjian.3032@bytedance.com> Signed-off-by: Corey Minyard Signed-off-by: Sasha Levin --- drivers/char/ipmi/ssif_bmc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/char/ipmi/ssif_bmc.c b/drivers/char/ipmi/ssif_bmc.c index 310f17dd9511a..c2e59899f1c4c 100644 --- a/drivers/char/ipmi/ssif_bmc.c +++ b/drivers/char/ipmi/ssif_bmc.c @@ -163,6 +163,8 @@ static ssize_t ssif_bmc_read(struct file *file, char __user *buf, size_t count, spin_unlock_irqrestore(&ssif_bmc->lock, flags); ret = copy_to_user(buf, &msg, count); + if (ret > 0) + ret = -EFAULT; } return (ret < 0) ? ret : count; -- 2.53.0