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 EDA3C403E9A; Wed, 20 May 2026 18:42:20 +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=1779302542; cv=none; b=TX9KLwcKiBJdTSxDZ5NYxJCRsEI+Hs6dAEY7QYtYkIeUGwh1r6z/mo7yo0q00cbjF2+CtuDbLu/UdwPZRAcDDLTy0vXM8gH/GONeADPcUNewTcDTLv39UlBhDmddiZM3VyoPKOBJAM4yOCWYC7fZSQ+g4D6HFM2YTQVCHf2VNAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779302542; c=relaxed/simple; bh=aX5k7NgNtouCarVxlZ421LZySKE9qW3Micln4CfxtKs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Wgqe332sB0CCy3KYcVwcuyuCWCnGtepkBbEKXHrnnV+qzVvCcaTFkBgmB64m13FIFGF5NBZyKnQoXtEM40dimKjGVZYz8eRSnYSQPUtp5DZrbHhGKCzn+QtBXXyn0ENGQAtxy0uf2bLBO0+TegRozWO0EpPHgkiTFwSx+rfDNek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ysS//uL/; 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="ysS//uL/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EAEA1F000E9; Wed, 20 May 2026 18:42:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779302540; bh=m/F5AJ0GzktEWKHf9fGtBeOytbylWv6GkWwsLREdGxk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ysS//uL/0GveeEspxsuyvu4FwUzGuPcEpdH4mOCzZb4h/zqmZoMTG5gcDMOEVWYg5 k1GtE2tMS4TJamI18/te8TlsUoFuONU+NUoY32Vz1uGHB0EhrB/CzOb+n2kDp8fQ2q NWR3Jl2c7717sVMFXPvf/e8PjZ6/36ECbLczywlM= 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 6.6 254/508] ipmi: ssif_bmc: fix missing check for copy_to_user() partial failure Date: Wed, 20 May 2026 18:21:17 +0200 Message-ID: <20260520162104.151952479@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162058.573354582@linuxfoundation.org> References: <20260520162058.573354582@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-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 e8460e966b83e..6928adb5df5ab 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