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 B0462386C1C; Tue, 21 Jul 2026 20:34:55 +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=1784666096; cv=none; b=XRu+uvkEcPV5AY+o2E0Ypj9TlEwIwLmS9GWCRBh25liDjVm15s2nUarJtOaCo4sNdLOsRHczdaDByuv014FGBBTPsKD/jriGnlMBq3y2mAvR3rSkjPSmRJJStqjl4uuOPd5K+s89UI/cV9m7vDtSzMymDOsXbv3zGZxtOVFJlDU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784666096; c=relaxed/simple; bh=9v9b+Ew5cf/1gUI3Ukmxov6RWbslP/7HrGNdAQP214U=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=OGo0UyugglqGiEHiNppAlUPBlIq/yU6KRdpqKZ0H+3OgpMIRl0Cg0VrqXgmamIZI8qaDThOVwQ93L9+NVhUsWCkq+gruAaLGOTxvvmQup7VqNDHCZSLofoPTT8/vLTQ4JdLZeoJL9lLm31EAS6IDbObXc7x7u1mgYSVTanNw3ks= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=TtYezsTE; 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="TtYezsTE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20CD11F000E9; Tue, 21 Jul 2026 20:34:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784666095; bh=6JmDBEKmnvYpWH9AF/sXD6Xst4RZjbxhvipwLau+4s4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=TtYezsTE8S8XWEjJv5GycArpUNzQPXhV58P3kD4D+EYstQskqiMb4ROfeyy+b4MpX 4l3ja16uUXZxmdZ+hNI35E5l1gAfUCW84LXxpGdh84lQZS65ualyLyGNZIw3kDZwg7 HtDLD0tVORuG6vSPdUkF/hfLRu5Kn8uAQssTIB6Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yuho Choi , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 6.6 0509/1266] ACPI: IPMI: Fix message kref handling on dead device Date: Tue, 21 Jul 2026 17:15:46 +0200 Message-ID: <20260721152453.236485340@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152441.786066624@linuxfoundation.org> References: <20260721152441.786066624@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: Yuho Choi [ Upstream commit 63320db6a5d84ec3fed8b3d36ba5244d07ddd108 ] acpi_ipmi_space_handler() takes an extra reference on tx_msg before checking whether the selected IPMI device is dead. The reference belongs to the tx_msg_list entry and is normally dropped by ipmi_cancel_tx_msg() or ipmi_flush_tx_msg() after the message is removed from the list. On the dead-device path, the message has not been queued yet, but the error path still calls ipmi_msg_release() directly. That bypasses kref_put() and frees tx_msg while the queued-message reference is still recorded in the kref count. Take the queued-message reference only after the dead-device check succeeds, immediately before adding tx_msg to the list. Fixes: 7b9844772237 ("ACPI / IPMI: Add reference counting for ACPI IPMI transfers") Signed-off-by: Yuho Choi Link: https://patch.msgid.link/20260603163108.2149359-1-dbgh9129@gmail.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/acpi_ipmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/acpi/acpi_ipmi.c b/drivers/acpi/acpi_ipmi.c index 0555f68c2dfd68..148d9486106cad 100644 --- a/drivers/acpi/acpi_ipmi.c +++ b/drivers/acpi/acpi_ipmi.c @@ -545,7 +545,6 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address, return AE_TYPE; } - acpi_ipmi_msg_get(tx_msg); mutex_lock(&driver_data.ipmi_lock); /* Do not add a tx_msg that can not be flushed. */ if (ipmi_device->dead) { @@ -553,6 +552,7 @@ acpi_ipmi_space_handler(u32 function, acpi_physical_address address, ipmi_msg_release(tx_msg); return AE_NOT_EXIST; } + acpi_ipmi_msg_get(tx_msg); spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags); list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list); spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags); -- 2.53.0