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 8145349620 for ; Thu, 27 Feb 2025 02:08:32 +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=1740622112; cv=none; b=TkAd6plSPHex1m3s1z2gYM1oRIbK78NeAWHT2UBmVI1apFyb3xzvaPIdqE/ajZmyc9LxA/6V+G1Nc0ntiuQ5wjCkzp/4CP40ZZkEZshJFPmZ37JmC/RA8O6Yd+Ulo5p7wvNGW+ZSsJq57hbExMAW2QayDtAobOkCavTbiL+nqog= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740622112; c=relaxed/simple; bh=yWT25PaQzFO2kpcsig6JHRez/1RXqDuB0bYKLWNxGeo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=MoV4Ts5P9RMPmRijXX20pOJWuaiXu5Wygc4NFxwX3Xxg1Jr07/i3INfcxI4/3x1mPnOVWZlkv6KSXyHZPgZh6Y/xlAZdQQiZ8ERnldLlY0bHwg2FanATJlDuyNTIt+vxAPODOy5nyr3S9G5eGV87UXQwp9YsJSeuCbJuotlz8ok= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AXzKzvlE; 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="AXzKzvlE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E32C4C4CEE2; Thu, 27 Feb 2025 02:08:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1740622112; bh=yWT25PaQzFO2kpcsig6JHRez/1RXqDuB0bYKLWNxGeo=; h=From:To:Cc:Subject:Date:Reply-to:From; b=AXzKzvlEbs3zwvMgFf6fBcszihC6kL6ssV01RaAIs3y/XyLceSJBCiXSRW0D9iDLX 8OvajDyJ3M52mjaNn2ALDYeZGLLt3Wfhn+XHSDmuBu3aDpq/8QkptYQXjz/p/38rcP FohWrgEPaSx6vWTj3n9ao7HdCJ0re5z6AMbQkmNg= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2024-57982: xfrm: state: fix out-of-bounds read during lookup Date: Wed, 26 Feb 2025 18:05:41 -0800 Message-ID: <2025022635-CVE-2024-57982-c76a@gregkh> X-Mailer: git-send-email 2.48.1 Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Reply-to: , X-Developer-Signature: v=1; a=openpgp-sha256; l=3151; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=yWT25PaQzFO2kpcsig6JHRez/1RXqDuB0bYKLWNxGeo=; b=owGbwMvMwCRo6H6F97bub03G02pJDOn7T+T7VfuEKfJNnm4h+tPgX/S65S/lX+52CDv8cn3SC QO3nOkFHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjCR/HSGBdfOmcp//G+YpXhj 5+2FH4xnsmWkRDIsmL+lNOSijVHojhsJdWznlk/N+7y2DAA= X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit Description =========== In the Linux kernel, the following vulnerability has been resolved: xfrm: state: fix out-of-bounds read during lookup lookup and resize can run in parallel. The xfrm_state_hash_generation seqlock ensures a retry, but the hash functions can observe a hmask value that is too large for the new hlist array. rehash does: rcu_assign_pointer(net->xfrm.state_bydst, ndst) [..] net->xfrm.state_hmask = nhashmask; While state lookup does: h = xfrm_dst_hash(net, daddr, saddr, tmpl->reqid, encap_family); hlist_for_each_entry_rcu(x, net->xfrm.state_bydst + h, bydst) { This is only safe in case the update to state_bydst is larger than net->xfrm.xfrm_state_hmask (or if the lookup function gets serialized via state spinlock again). Fix this by prefetching state_hmask and the associated pointers. The xfrm_state_hash_generation seqlock retry will ensure that the pointer and the hmask will be consistent. The existing helpers, like xfrm_dst_hash(), are now unsafe for RCU side, add lockdep assertions to document that they are only safe for insert side. xfrm_state_lookup_byaddr() uses the spinlock rather than RCU. AFAICS this is an oversight from back when state lookup was converted to RCU, this lock should be replaced with RCU in a future patch. The Linux kernel CVE team has assigned CVE-2024-57982 to this issue. Affected and fixed versions =========================== Issue introduced in 4.9 with commit c2f672fc94642bae96821a393f342edcfa9794a6 and fixed in 6.12.13 with commit a16871c7832ea6435abb6e0b58289ae7dcb7e4fc Issue introduced in 4.9 with commit c2f672fc94642bae96821a393f342edcfa9794a6 and fixed in 6.13.2 with commit dd4c2a174994238d55ab54da2545543d36f4e0d0 Issue introduced in 4.9 with commit c2f672fc94642bae96821a393f342edcfa9794a6 and fixed in 6.14-rc1 with commit e952837f3ddb0ff726d5b582aa1aad9aa38d024d 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-2024-57982 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/xfrm/xfrm_state.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/a16871c7832ea6435abb6e0b58289ae7dcb7e4fc https://git.kernel.org/stable/c/dd4c2a174994238d55ab54da2545543d36f4e0d0 https://git.kernel.org/stable/c/e952837f3ddb0ff726d5b582aa1aad9aa38d024d