From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 CB92E3E5578 for ; Fri, 8 May 2026 13:26:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778246796; cv=none; b=ltRpozjOt89x51yA3r5ca2tw5OaPwfbHZReUpQ1iG1aISjAnD9mesJ2cZ9CZxhCKEGP6i20vlpaoIff3S90UpKpv+XCU/1BnNDbpN5pFH3bMPn/UcdZmjtOTm+32qqwWPpNpHrdwjBeR0KuURKEcHw7P2LQuJ7m+rFu0kdXOppE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778246796; c=relaxed/simple; bh=zc03EF0dwpvqG0xb/egVEicwuWmd7IJLh9IiQX41k4Q=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=AuYcGOvcHoDHJjIcDjGOJ571VlKGvkKBC+0cXajaL3IFtNd6TPf5LH29RJf47K9sFjzJq9olO6aB8kaFoYHbyqq5NX/B1kBN5f9ixkaI1t31GyES1eilXUOl8sg1WsVK5e9sldZfRD0s9XxzOnXaE0fNbM+BWVxsAU8HArWzjYA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=CITNZ1+R; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="CITNZ1+R" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A77AEC2BCB0; Fri, 8 May 2026 13:26:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778246796; bh=zc03EF0dwpvqG0xb/egVEicwuWmd7IJLh9IiQX41k4Q=; h=From:To:Cc:Subject:Date:Reply-To:From; b=CITNZ1+RxWwtbQ0krhBvJgCfZtIhSGkB+t8XtK2hHKRv1Nyo+CS0YxmDnUAUc0arI yTnujB0EBWf7RZHyME19DgWWoWyauVMk19jpzs7EyfZNAmjV/+6OEs9/GwIs7uOec1 8XVpHrpMsLM67Ztfv33bxM2jtA8Rgj/LHkmYS5UM= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-43319: spi: spidev: fix lock inversion between spi_lock and buf_lock Date: Fri, 8 May 2026 15:26:22 +0200 Message-ID: <2026050819-CVE-2026-43319-6745@gregkh> X-Mailer: git-send-email 2.54.0 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=2989; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=UdEfI/mRUmZP/ayvq1GYGsk9lj4jtAyNEsn1hwwdVyE=; b=owGbwMvMwCRo6H6F97bub03G02pJDJl/n1THRj97Mffp6Z6qkJjsBR92NzCvW3Pm1pqCOOXMp d0i6lOtOmJZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAilrsY5vs7qxWtuawUdfZA l4Rr2dsTG49Y+DPMj5/s4RjwelfWJsW+6YUSqyfJbfi0BgA= 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: spi: spidev: fix lock inversion between spi_lock and buf_lock The spidev driver previously used two mutexes, spi_lock and buf_lock, but acquired them in different orders depending on the code path: write()/read(): buf_lock -> spi_lock ioctl(): spi_lock -> buf_lock This AB-BA locking pattern triggers lockdep warnings and can cause real deadlocks: WARNING: possible circular locking dependency detected spidev_ioctl() -> mutex_lock(&spidev->buf_lock) spidev_sync_write() -> mutex_lock(&spidev->spi_lock) *** DEADLOCK *** The issue is reproducible with a simple userspace program that performs write() and SPI_IOC_WR_MAX_SPEED_HZ ioctl() calls from separate threads on the same spidev file descriptor. Fix this by simplifying the locking model and removing the lock inversion entirely. spidev_sync() no longer performs any locking, and all callers serialize access using spi_lock. buf_lock is removed since its functionality is fully covered by spi_lock, eliminating the possibility of lock ordering issues. This removes the lock inversion and prevents deadlocks without changing userspace ABI or behaviour. The Linux kernel CVE team has assigned CVE-2026-43319 to this issue. Affected and fixed versions =========================== Fixed in 6.12.75 with commit f8431b8672231d378b03176fe74c95adfd3522cf Fixed in 6.18.16 with commit e341e18215030af2136836b78508e0d798916df7 Fixed in 6.19.6 with commit 41ccfac7d302968a4f32b5f7b012d066c5f5cdf8 Fixed in 7.0 with commit 40534d19ed2afb880ecf202dab26a8e7a5808d16 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-2026-43319 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/spi/spidev.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/f8431b8672231d378b03176fe74c95adfd3522cf https://git.kernel.org/stable/c/e341e18215030af2136836b78508e0d798916df7 https://git.kernel.org/stable/c/41ccfac7d302968a4f32b5f7b012d066c5f5cdf8 https://git.kernel.org/stable/c/40534d19ed2afb880ecf202dab26a8e7a5808d16