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 C1D881624DF for ; Tue, 28 Jul 2026 19:30:21 +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=1785267022; cv=none; b=KNdZFaoK1LN5RP5M+1J/QG1qqP/8i431gpZ+6/+q9Vfp4VT63QkP5v6CwoMZuRXwEfjW58K8faVTRqnVJ0yauoch0qRKs46KtC826oD3jN/saizC3ILbrYO2nP/2KroeP4MqWNyNH05MfRggfhrDxqzpMrkxoiEFNBcO4ueMIoI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785267022; c=relaxed/simple; bh=Ujf6K8321O6sV/uxeWboTxwq2KIn6jXQJr27MvlPQU0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RWitlZwfqWbaOylKFUHCRneHgQJFrZNSZU9rYZwtWgrtb3Q2cUla2+SR2u4S1zsDRqxcRfjuVJyMjpVCdT/gZsfSSDwX+iRYkEuFTmUlxrVZ7LBsdfBpijPRr1juKEkA1gVUwFEw0gSu0zgYn0HrEuYdSeR0IsBJuF/xCdlCwlA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CCibAemT; 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="CCibAemT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EEE5A1F000E9; Tue, 28 Jul 2026 19:30:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785267021; bh=xpdWXB8JNMlyL7T/06ctlNMzDT7yu1GIeLYXJqpQYtg=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=CCibAemTAnZQLw2yf6ajBoTzehLgmiU0XU6jxxZtk+s0OosIOOTGzMS1YFTff2GvB Is5jFKxg7guTQR7Pu528vcvyBj9zHoLNdNgp9JA1BlbpdPPco1lPU9bDQZXeH7MHYe kto5r2jBMDk0QBLkGZeZAMDRU7XzOZL63MdiGScZVBkkCRR8nbBajln0+XnRZimeKO JBVeD8QCEuc04pmvdHUtYncf/NJQDNGfz6tbuXRVbj9LpCR3iHZCdOURALQIht+Pte PFW6vPNYanFAqyjeZC0Umf2cmWYYHFZi9k/fJ8GD/xmdd5xPNlQysmGDPnJhykgXoy fzongdA6uImiQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Wentao Liang , Corey Minyard , Sasha Levin Subject: [PATCH 6.1.y] ipmi: fix refcount leak in i_ipmi_request() Date: Tue, 28 Jul 2026 15:30:19 -0400 Message-ID: <20260728193019.456162-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026072152-tripod-washtub-9b4d@gregkh> References: <2026072152-tripod-washtub-9b4d@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 62d39ea9f00836..48f2a2ca8278f5 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