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 DB85955C1DA for ; Fri, 11 Sep 2026 19:48:07 +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=1789156091; cv=none; b=jY6ANKJ3pyx/tohkGN+hnLo7HfFO1CZuRxMSfchL/cQCkCUXYNlmk+p0NsNZf0gfbbGrgCvd+CBs6O4vCMsNuvztc5sD9RAm3AxqwfdeJ/bvi30uOlL1pGPxb6ztM8PUi36OOHyGjxPveOSFVvP06F8DC1I//BwD74oTRKjbxvQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156091; c=relaxed/simple; bh=PKcnlrNhti+amwVsMz94gKot4mBIbRGETFSXrUydCXw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=CO5edF5eyAP+VM6pxyTyJSjUudBbYNnItAadH89iar9OP0hfQ7+7xohyXUMFo5a1mX2fYythMBNFyOmX+VAOqMqwNegIDlLX+nA15FJYbcZpDAUytdOCpGoBPdt7kyfS116Fp0w9+in406pdxB3Flocm9W6RU3lbmvnMOdks0Tk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=NthU5WIn; 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="NthU5WIn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A4AB1F00898; Fri, 11 Sep 2026 19:48:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156085; bh=dOScXLhdBRXpfGeeFaBrs0etD0ZN3j+hE+ogY7jJeuI=; h=From:To:Cc:Subject:Date:Reply-To; b=NthU5WInMkH6ixxiL4Ftyj19j5wjfeKF4XpeaEjw8MiDBs32DaHMZ24IpBhsqJySl foJxb0qN9SFQGOT0qKXyTTHslreSKxe/Lox6MQ+Sb+0YFTaIx+OCK6TwmAwsYTjcJq 7Oyk7ug0An3eTZACl2bTyr7UXZ4Uc8PE3y+TITOs= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-80982: net/smc: fix use-after-free in smc_rx_pipe_buf_release() Date: Fri, 11 Sep 2026 21:41:28 +0200 Message-ID: <2026091146-CVE-2026-80982-45b7@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=3135; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=Hj4E4gOaIRamnhxGnMVdaqIomBMtb+K2RTugWFLnFIY=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIu0v5JnJZnau3xO3Yvs80cVKa3OU5pQdUjRKT9duP 8O154NPRywLgyATg6yYIsuXbTxH91ccUvQytD0NM4eVCWQIAxenANzkJQwLzjWtzp0tUfFnjkac LE+xE1dMyulkhvlptg0XVwfOkNmfHtWXZbP06FtTkT8A 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: net/smc: fix use-after-free in smc_rx_pipe_buf_release() smc_rx_splice() hands RMB pages to a pipe and takes a socket reference per entry so the smc_sock stays alive until the reader finishes. The connection does not: a concurrent close runs smc_conn_free(), which releases the receive buffer back to the link group pool. smc_rx_pipe_buf_release() tests sk_state before taking the socket lock. The state can change between the test and the lock, and smc_rx_update_cons() then dereferences conn->rmb_desc and walks conn->lgr, which smc_conn_free() has already released. On the is_reg_err path smcr_buf_unuse() frees the descriptor outright, so this is a use-after-free. Take the socket lock first and test conn->freed instead. smc_conn_free() sets that flag before releasing anything, and every caller holds the socket lock. The two paths exclude each other: either the pipe release runs first with everything valid, or it sees the flag and skips the update. The Linux kernel CVE team has assigned CVE-2026-80982 to this issue. Affected and fixed versions =========================== Issue introduced in 4.18 with commit 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and fixed in 6.12.109 with commit 6a644a7340df978785f3109d1e0726a982ce2c6f Issue introduced in 4.18 with commit 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and fixed in 6.18.50 with commit 0761e49aa78c2f1362511054c6e9670653858837 Issue introduced in 4.18 with commit 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and fixed in 7.2.4 with commit 0926f59ca0f94120895b92180c636a48d0ed3a6d Issue introduced in 4.18 with commit 9014db202cb764b8e14c53e7bacc81f9a1a2ba7f and fixed in 7.3-rc1 with commit c924884743e948e25625b7fbf3ee2a9325a204a7 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-2026-80982 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: net/smc/smc_rx.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/6a644a7340df978785f3109d1e0726a982ce2c6f https://git.kernel.org/stable/c/0761e49aa78c2f1362511054c6e9670653858837 https://git.kernel.org/stable/c/0926f59ca0f94120895b92180c636a48d0ed3a6d https://git.kernel.org/stable/c/c924884743e948e25625b7fbf3ee2a9325a204a7