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 333C83A873E for ; Tue, 28 Jul 2026 18:07:44 +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=1785262066; cv=none; b=oAq8geaDQtIHTwKKs2dNcAWspJxUWkF0fi8g4rFSnqFS67XPvfXvEow67rsxYRy3h0qEjV6Al2zg2on9+gOWzi0FequtlNb4JaBV0RYuejCgS/hTtBk6GDRd81VaUiZbXuJkXzjmH/A55ogPE+QzZ6nI5mKgswhxwq8vHwkfmPw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785262066; c=relaxed/simple; bh=y0qua/8HgjlUtZLbNPmcAbIwEP39cmmWrKZ3cjUfgSc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=o5HwQ69cYM4Hoky7jo3PQrV1+52awMpgTvoxz2/m5ooIfCbkHd9Q0nl+GEsApUMdbOf20y01/JhXVeFFusPbNIc2kolnPtzQQeBYgcz3kyshmexTA3Maw3vBnzhAKknFg4xoxi1foB6wNOkulxwEdFv9SNopABTOKXx/WfGOr+g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Lt2ua7pv; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Lt2ua7pv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2BF0F1F000E9; Tue, 28 Jul 2026 18:07:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785262064; bh=YkxeFpytX1opw7hvf8l4bGpSAJtgOHI1A+NfyKH7Aoc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Lt2ua7pvuAYnAQwCVaM8vTYYEVri6YSuwKD8/xSlUMN/rEFAOtoYQ0EFApBYsdBur OYewcb/E9yrfoMvS3W/fjdynV0DWlkgXaOTMX91CsTWk22vfX24ulpTeAahpTPjilh RybeiINqQJjqLn5yrKUWmmN3r2/J99QI3v4SSv00zimwGnw+9Ceh9HcvF5bPo+dKgr 5pRd18QLHzg9JZoQ00QeNl3IaQykIIrCYseF6XV7zAlnbJRqHdxX+eAI9HfwU69TJ1 YBwugJKj/4SguH7d8Jct6aa7VsF/iu/QHgj5SqMfaNlT2WERnWvU0InUO2xy13c3Q+ rX/kxCh/VsGqg== From: Sasha Levin To: stable@vger.kernel.org Cc: Wentao Liang , Corey Minyard , Sasha Levin Subject: [PATCH 6.6.y] ipmi: fix refcount leak in i_ipmi_request() Date: Tue, 28 Jul 2026 14:07:42 -0400 Message-ID: <20260728180742.291994-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026072152-astute-spore-9b56@gregkh> References: <2026072152-astute-spore-9b56@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Wentao Liang [ Upstream commit a3f3859cecacb64f18fd446271ece9a3b3f2d4de ] When a caller provides a `supplied_recv` message to i_ipmi_request(), the function increments the user's `nr_msgs` reference count. If an error occurs later, the out_err cleanup path only frees the recv_msg if the function allocated it itself (i.e., !supplied_recv). In the supplied_recv case the cleanup is skipped, leaving the reference count elevated. The caller ipmi_request_supply_msgs() does not release the supplied_recv on error, so the reference is permanently leaked. Fix this by explicitly reverting the reference count operations when a supplied recv_msg with a valid user pointer is present in the error path: decrement nr_msgs and drop the user's kref. Cc: stable@vger.kernel.org Fixes: b52da4054ee0 ("ipmi: Rework user message limit handling") Signed-off-by: Wentao Liang Message-ID: <20260603120634.3758747-1-vulab@iscas.ac.cn> Signed-off-by: Corey Minyard [ changed `free_ipmi_user` to `free_user` in the two added `kref_put()` calls ] Signed-off-by: Sasha Levin --- drivers/char/ipmi/ipmi_msghandler.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index 37b84bfa623e99..7dec2138b87445 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -2331,6 +2331,10 @@ static int i_ipmi_request(struct ipmi_user *user, if (smi_msg == NULL) { if (!supplied_recv) ipmi_free_recv_msg(recv_msg); + else if (recv_msg->user) { + atomic_dec(&recv_msg->user->nr_msgs); + kref_put(&recv_msg->user->refcount, free_user); + } return -ENOMEM; } } @@ -2373,6 +2377,10 @@ static int i_ipmi_request(struct ipmi_user *user, ipmi_free_smi_msg(smi_msg); if (!supplied_recv) ipmi_free_recv_msg(recv_msg); + else if (recv_msg->user) { + atomic_dec(&recv_msg->user->nr_msgs); + kref_put(&recv_msg->user->refcount, free_user); + } } else { dev_dbg(intf->si_dev, "Send: %*ph\n", smi_msg->data_size, smi_msg->data); -- 2.53.0