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 5FEDA43DA5C for ; Mon, 20 Jul 2026 16:28:42 +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=1784564926; cv=none; b=McGf3Teak458E7c4LIJHbIkMMIaVjKWL2QAB8y/4/nEL9DXUKIVODtsrmjvkRF8jENPBuxb456FBQJoU11lLowmNOmbXonLv9O89QNHwHAie1czanbJg3lywrGnQNxTSmFzhMrHFTR5N4UgR0+Pz9J84DfljMZMnFBL8rMGndxM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784564926; c=relaxed/simple; bh=eQaIfwPb+G92SDHVtNm7SxQOrYobYgvE+EMz9QMvuHY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Pd02NLZORWaG7ubShGZS5UGyn+zT8rVEcc+7y1qncqDnmz2t3tBvFCm4ruMt0DmpUvH3Y7PIegv5FICu7h8V/G9jMepmizyspP1fOWe6JkXpgB1DfoD6CZXD1QRTTb0wSXT5FEqMPm1Fps4hWWM6YhowxdeQqcMBvBEw6YjMDJU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=D+wRON2N; 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="D+wRON2N" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 98A5A1F000E9; Mon, 20 Jul 2026 16:28:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784564922; bh=OfPkL+8+7lXvkQsIJxwz9zNoy8hRM2ojql6ENdz0VZA=; h=From:To:Cc:Subject:Date:Reply-To; b=D+wRON2NytLnXpemPmyjN1xIXoWlAuiW8oZESlcUArB5aq/5k5gjHP4d24FkSy1a1 vDs3HJaj27iQBiTDJ6275ahtgRMAE0+Tc2wn4gTFpQ34YHfH9u/zoiZXpg+F49CGRt ORd31htj3qVT7wnAMYu9cpVkQNn0XWooG+fU3A78= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64205: i2c: i801: fix hardware state machine corruption in error path Date: Mon, 20 Jul 2026 18:27:56 +0200 Message-ID: <2026072052-CVE-2026-64205-9724@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=3408; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=UwhA9kSnzroDqnLfeg4JbFsEcIC1sfMDPGKmNLU7HWM=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlxPh072q4yfAmqfbWEXdY1751c3Mb7reevXWTfED7L7 yxjz+/7HbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjAR1Q8Mc4XUaz+pX9dRnlfz 94EeR1CgQcnh4wzzNLya/ld4LeZp3hPi6bTMeMXWVT3qAA== 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: i2c: i801: fix hardware state machine corruption in error path A severe livelock and subsequent Hung Task panic were observed in the i2c-i801 driver during concurrent Fuzzing. The crash is caused by an unconditional hardware register cleanup in the error handling path of i801_access(). When i801_check_pre() fails (e.g., returning -EBUSY because the SMBus controller is actively used by BIOS/ACPI), the kernel does not actually acquire the hardware ownership. However, the code jumps to the 'out' label and executes: iowrite8(SMBHSTSTS_INUSE_STS | STATUS_FLAGS, SMBHSTSTS(priv)); This forcefully clears the INUSE_STS lock and resets the hardware status flags without owning the controller. Doing so interrupts ongoing BIOS/ACPI transactions and totally corrupts the SMBus hardware state machine. Consequently, all subsequent i801_access() calls fail at the pre-check stage, triggering an endless stream of "SMBus is busy, can't use it!" error logs. Over a slow serial console, this printk flood monopolizes the CPU (Console Livelock), starving other processes trying to acquire the mmap_lock down_read semaphore, ultimately triggering the hung task watchdog. Fix this by moving the 'out' label below the hardware register cleanup. If i801_check_pre() fails, we safely bypass the iowrite8() and only release the software locks (pm_runtime and mutex), strictly adhering to the rule of not releasing resources that were never acquired. The Linux kernel CVE team has assigned CVE-2026-64205 to this issue. Affected and fixed versions =========================== Issue introduced in 6.3 with commit 1f760b87e54cf56a25ab68f8dc625e339f6e46d5 and fixed in 6.18.39 with commit bb5133a7d5f3fe5c387770e25f2e00e682ce11ed Issue introduced in 6.3 with commit 1f760b87e54cf56a25ab68f8dc625e339f6e46d5 and fixed in 7.1.4 with commit 00904687b9c5527d569d9a1ca72119823e735a61 Issue introduced in 6.3 with commit 1f760b87e54cf56a25ab68f8dc625e339f6e46d5 and fixed in 7.2-rc1 with commit 10dd1a736d557e310a77117832874729a0175d57 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-2026-64205 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/i2c/busses/i2c-i801.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/bb5133a7d5f3fe5c387770e25f2e00e682ce11ed https://git.kernel.org/stable/c/00904687b9c5527d569d9a1ca72119823e735a61 https://git.kernel.org/stable/c/10dd1a736d557e310a77117832874729a0175d57