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 5E46F43DEC5 for ; Fri, 11 Sep 2026 19:49:13 +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=1789156187; cv=none; b=XnzSpT10CNY7QxHZXRG0tZViJYY91okjT1GXgYpQFoChEg9YWum/8rEuusM3wmQWuSXcp0KC6x+in/mVWY17jGh5XFD6fmnLoxyNTeXtZdntv8m9toNRpT23fKNJ8wYXSHEXq0E2fWGowe0wXazWlhPigYk6GYT1iuf/8s6mXko= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156187; c=relaxed/simple; bh=K6Au/uv1Nus4frFo03GUigtpi5K+CzBtC6wCfzE3raI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=JbkWyQocXT+NNBN0q5X6oBv1CvC8KUlWrw/uZVOa5WeXCT9qFLMRLGTXyoueUx7u5lmXkSDqLlOmxi2UMt15kzfSinKUmet6KIAWnlGb2bkEIIsFi7BvzePfvtYPGVLU+t18YbkQjUMyVEjpLIwzOA4MUR9gSPDXaBzjzQwiRBg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2Vr8C3mm; 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="2Vr8C3mm" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC43A1F000FF; Fri, 11 Sep 2026 19:49:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156151; bh=RZgkC0PpimeQwRB+wXt1LOJXYs26d9r+XSSStxRPrz8=; h=From:To:Cc:Subject:Date:Reply-To; b=2Vr8C3mmqKXvx4t+7f5/n7C+Ew5kPh3tp4FIJen+laBBbqUyRKBFcokIdIVttq9fK SQazoM4cgDoVlBXOSHA2QfivzhU5GgTbyMliLrdGm3HA8QI8ZqvenqAgzxtQIkSNYs jtJZbqgPQBe5yxFmyYqjMpHrkX9sb0l+bGgwalFw= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-81005: ipmi: si: Fix NULL pointer dereference after failed registration Date: Fri, 11 Sep 2026 21:41:51 +0200 Message-ID: <2026091152-CVE-2026-81005-1bd2@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=4594; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=3gAirCvP1dmm0DdcCbrU/Gi9a97FzyNZYWF34egzL4s=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIl0MpVL7Xhf9vXHe6jJr1Kl1u0wKtNuWzChfyKrw8 nVgyeXqjlgWBkEmBlkxRZYv23iO7q84pOhlaHsaZg4rE8gQBi5OAZjIx6cMC2avaO88fetXy5fp wa9eXmVe8zVXUp1hvlPHeSHFOtPZBi6VLw2YrGa/Pd9yHAA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: ipmi: si: Fix NULL pointer dereference after failed registration try_smi_init() allocates new_smi->si_sm and later calls ipmi_register_smi_mod(), which maps to ipmi_add_smi(). During ipmi_add_smi(), the upper IPMI message handler obtains the initial BMC device information through __bmc_get_device_id(). This can fail if the BMC does not return a successful response to the Get Device ID command. When the BMC returns a nonzero completion code, the device-id helper retries the command and eventually returns -EIO if the device ID still cannot be fetched. On this failure path, ipmi_add_smi() logs "Unable to get the device id" and goes to out_err_started, where it invokes the lower driver's shutdown callback. try_smi_init() then logs the returned registration failure: ipmi_si IPI0001:00: IPMI message handler: Unable to get the device id: -5 ipmi_si IPI0001:00: Unable to register device: error -5 For ipmi_si, the shutdown callback is shutdown_smi(), which cleans up the SI state machine data, frees smi_info->si_sm, and sets smi_info->si_sm and smi_info->intf to NULL. However, intf->in_shutdown is not set on this failed-registration rollback path. Therefore, the asynchronous redo_bmc_reg work item can still retry BMC device-id probing after the lower driver has already cleared its SI state machine data. In the observed case, that retry path reached start_next_msg(), which passed the NULL smi_info->si_sm pointer to the selected KCS state machine handler: BUG: unable to handle kernel NULL pointer dereference at 0000000000000000 Workqueue: events redo_bmc_reg [ipmi_msghandler] RIP: start_kcs_transaction+0x2c/0x190 [ipmi_si] Call Trace: start_next_msg+0x50/0x80 [ipmi_si] check_start_timer_thread.part.9+0x3b/0x50 [ipmi_si] sender+0x69/0x80 [ipmi_si] i_ipmi_request+0x2ac/0x9d0 [ipmi_msghandler] __get_device_id.isra.29+0xaa/0x180 [ipmi_msghandler] __bmc_get_device_id+0xef/0x950 [ipmi_msghandler] redo_bmc_reg+0x52/0x60 [ipmi_msghandler] process_one_work+0x1a7/0x360 Set intf->in_shutdown on the out_err_started path before invoking the lower driver's shutdown callback. This prevents later redo_bmc_reg retries from using an interface whose lower driver state has been cleaned up, and applies the same shutdown state to other IPMI interfaces as well. The Linux kernel CVE team has assigned CVE-2026-81005 to this issue. Affected and fixed versions =========================== Issue introduced in 4.19 with commit 2512e40e48d21d8bac09f7e91d2c3ceb2d3b50b2 and fixed in 6.12.109 with commit d4be659a3e56f4eb16039ab8a1162efea086a714 Issue introduced in 4.19 with commit 2512e40e48d21d8bac09f7e91d2c3ceb2d3b50b2 and fixed in 6.18.50 with commit 53af3a8bae0a93c1342e1b5519812203332aca8e Issue introduced in 4.19 with commit 2512e40e48d21d8bac09f7e91d2c3ceb2d3b50b2 and fixed in 7.2.4 with commit 8ada17dd4c4ffd6b94621e735d77eda196ce118f Issue introduced in 4.19 with commit 2512e40e48d21d8bac09f7e91d2c3ceb2d3b50b2 and fixed in 7.3-rc1 with commit 6d920a75df9a83ab096b3cde7a643b656e4fdfeb Issue introduced in 4.18.10 with commit 288bd736c8a027040fc261c86a87b65e7bc3f6fa Please see https://www.kernel.org for a full list of currently supported kernel versions by the kernel community. Unaffected versions might change over time as fixes are backported to older supported kernel versions. The official CVE entry at https://cve.org/CVERecord/?id=CVE-2026-81005 will be updated if fixes are backported, please check that for the most up to date information about this issue. Affected files ============== The file(s) affected by this issue are: drivers/char/ipmi/ipmi_msghandler.c Mitigation ========== The Linux kernel CVE team recommends that you update to the latest stable kernel version for this, and many other bugfixes. Individual changes are never tested alone, but rather are part of a larger kernel release. Cherry-picking individual commits is not recommended or supported by the Linux kernel community at all. If however, updating to the latest release is impossible, the individual changes to resolve this issue can be found at these commits: https://git.kernel.org/stable/c/d4be659a3e56f4eb16039ab8a1162efea086a714 https://git.kernel.org/stable/c/53af3a8bae0a93c1342e1b5519812203332aca8e https://git.kernel.org/stable/c/8ada17dd4c4ffd6b94621e735d77eda196ce118f https://git.kernel.org/stable/c/6d920a75df9a83ab096b3cde7a643b656e4fdfeb