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 0201E383C89 for ; Sat, 15 Aug 2026 06:35:44 +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=1786775745; cv=none; b=CrrUWbOO0i8kXF5/uluunz7zz6GVHEHTxbpHpgQFoyVIJJ2A9rD1Ktf4w1KAj7IVOYxn9aLbq49YPptmmfzcaYnxqnlomYyjpplTfkKD1fnKGwvxBV0/RLIwsuhId3PyJ+3G5GWmbmwfu63H7NamCQhDOEK0lWJbzPiGlHtZyDE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786775745; c=relaxed/simple; bh=ntJ1E2f+AfX2mdVnHkNhx6wa0hxidVNbVUZnLAQa4vw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=EWwMmvmCiLreAZmShuApoz6ZU72pFN23VxBmBqTFPBh+qZHwhclr2dVNX1QHxwNGxV38d8ttLMATfQqj31JfPV4+3R1TDliuCIrZwhQdlm/dg2K38b1Y8p4VPJhBKU+IZkGsIJuD/TyfsUoFnc85OGAyollDZpOtiIxMlwyREm8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=LOG/XxNM; 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="LOG/XxNM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A0E61F000E9; Sat, 15 Aug 2026 06:35:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1786775743; bh=wFK1MTtlASa8WdOgD6M0XiNTv/FkJbyuZ/l51Swt+8Q=; h=From:To:Cc:Subject:Date:Reply-To; b=LOG/XxNMAYBEDLe5iiqBP7v/bO/EMo3n3Yivd5GbHl2qQYR/CFe1Zdbua1aL9FMK/ ohW1aWguVUrKn7B4PXCfKXi/em7ZfSijVxt532uGWxozj0o2ZAZVze6PjfVIe+RIjW K2teTibtrYdE0oGmqwGzYksURlDQzm1XxoYyhO24= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74290: net/sched: cls_flow: Dont expose folded kernel pointers Date: Sat, 15 Aug 2026 15:10:17 +0900 Message-ID: <2026081547-CVE-2026-74290-9a3d@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=3196; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=E3+C8s4JGfHsy1ZBeAjD0PFWplmQ1Wk2zm+xGjCo8rc=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkNjBxrLzslSS9/GV7vybJX7a/GFsY3XjYbL/t5Nz5XW WVUnbm3I5aFQZCJQVZMkeXLNp6j+ysOKXoZ2p6GmcPKBDKEgYtTACbyQZphwWRFyUWz77fUZH9n +dP78uGbq7f5BRjmxzAaV6UuP+P4+u3laveyKuf9fMkPAQ== 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/sched: cls_flow: Dont expose folded kernel pointers The flow classifier falls back to addr_fold() for fields that are missing from packet headers. In map mode, userspace controls mask, xor, rshift, addend and divisor, and can observe the resulting classid through class statistics. This allows a tc classifier in a user/network namespace to recover the 32-bit folded value of skb->sk, skb_dst() or skb_nfct(). Align with standard kernel practices for pointer hashing and replace the XOR folding with a keyed siphash (which is cryptographically secure) The Linux kernel CVE team has assigned CVE-2026-74290 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.25 with commit e5dfb815181fcb186d6080ac3a091eadff2d98fe and fixed in 6.1.178 with commit 19f2ecf8ea564562c7e7a919cf38068dd9aa1c96 Issue introduced in 2.6.25 with commit e5dfb815181fcb186d6080ac3a091eadff2d98fe and fixed in 6.6.145 with commit 3d054001860270748405a3f9270c5fa0bf7ffc19 Issue introduced in 2.6.25 with commit e5dfb815181fcb186d6080ac3a091eadff2d98fe and fixed in 6.12.97 with commit fb31fbe51c233f3bf47021121f63d2e42cac2d08 Issue introduced in 2.6.25 with commit e5dfb815181fcb186d6080ac3a091eadff2d98fe and fixed in 6.18.40 with commit 0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a Issue introduced in 2.6.25 with commit e5dfb815181fcb186d6080ac3a091eadff2d98fe and fixed in 7.1.5 with commit 6151159618198675e01c391676e579738286c135 Issue introduced in 2.6.25 with commit e5dfb815181fcb186d6080ac3a091eadff2d98fe and fixed in 7.2-rc1 with commit f294fc71c4a0fa4964f6428a1b4e7929c1d83125 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-2026-74290 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/sched/cls_flow.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/19f2ecf8ea564562c7e7a919cf38068dd9aa1c96 https://git.kernel.org/stable/c/3d054001860270748405a3f9270c5fa0bf7ffc19 https://git.kernel.org/stable/c/fb31fbe51c233f3bf47021121f63d2e42cac2d08 https://git.kernel.org/stable/c/0a8b5b74f0e6b6b9ce453bcfa4baa502c4c7577a https://git.kernel.org/stable/c/6151159618198675e01c391676e579738286c135 https://git.kernel.org/stable/c/f294fc71c4a0fa4964f6428a1b4e7929c1d83125