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 8081E3A75AC for ; Sun, 19 Jul 2026 15:42:56 +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=1784475777; cv=none; b=qWB/7A47DTn/Rf/dGiEqJHQFrlASUuMncD1pGGXmn6BkaLu4tyKkiw8jVaq/6wuHtnUE/+Mj/2nQucwpwDLOOjDf5jGWyZLTlEwqjWfR0KA0Y4tet4ehpJQdaVlVz3X72DlfeBXqeIg/FMT9MIODEA/vweKf6sYx33KABx9BKyk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784475777; c=relaxed/simple; bh=K39IsUiR30+J2Hwd58rsWv7fAbvK174NnM38fnh1Oek=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=W5hsFrFxbvasorySeRRdIEqVnPxxhCR/SxpdemvlZdxpDlgCnt04jbY04ZtRiVKy/dpXaPY4etL3rLHhql4HvjC058BRg6NJvQB3XLyL8YZW2Yz7r8D3oUhLbsU4M45QfJh59p0zcRhxo/ZGGCNGtxREsmydncMinT6PklgpNng= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2doLL41C; 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="2doLL41C" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A03951F000E9; Sun, 19 Jul 2026 15:42:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784475776; bh=rsMpTwKGqZAv8P6nOaI6D5nbuYNX4cop4PJvwjQdPtM=; h=From:To:Cc:Subject:Date:Reply-To; b=2doLL41CEzKATY2cxTHmDdxZyF4ml09b0T4mEBPKTD067bx4gC3cemP4IBN9860GR elTEDrRmLPv7mZJD/2WJkquQ4jyg8pazKwQuEIZ481/nRDdAZCgIgGykPwmbF1Dd5O E6pJJNxOSUDwoBTuhPmDqc9Ju4OM7oGaA6KBNOz0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64079: netfilter: x_tables: allocate hook ops while under mutex Date: Sun, 19 Jul 2026 17:39:01 +0200 Message-ID: <2026071915-CVE-2026-64079-866e@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=3097; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=kuNDf3XyYLIuNvipfZ0GllIytaDTYoXwqzB8TYHbe6Q=; b=owGbwMvMwCRo6H6F97bub03G02pJDFkx79O1S4JZsp0Dl0s47yqJ15av19VYJplaeeVc9On52 gqCrZ4dsSwMgkwMsmKKLF+28RzdX3FI0cvQ9jTMHFYmkCEMXJwCMJGLJgzzrF1K3l31ufq/6bqx 6otZ5dk3vu1nYJhnGb60OkyzqP3Yz5DCno8Mt44Jb9MEAA== 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: netfilter: x_tables: allocate hook ops while under mutex arp/ip(6)t_register_table() add the table to the per-netns list via xt_register_table() before allocating the per-netns hook ops copy via kmemdup_array(). This leaves a window where the table is visible in the list with ops=NULL. If the pernet exit happens runs concurrently the pre_exit callback finds the table via xt_find_table() and passes the NULL ops pointer to nf_unregister_net_hooks(), causing a NULL dereference: general protection fault in nf_unregister_net_hooks+0xbc/0x150 RIP: nf_unregister_net_hooks (net/netfilter/core.c:613) Call Trace: ipt_unregister_table_pre_exit iptable_mangle_net_pre_exit ops_pre_exit_list cleanup_net Fix by moving the ops allocation into the xtables core so the table is never in the list without valid ops. Also ensure the table is no longer processing packets before its torn down on error unwind. nf_register_net_hooks might have published at least one hook; call synchronize_rcu() if there was an error. audit log register message gets deferred until all operations have passed, this avoids need to emit another ureg message in case of error unwinding. Based on earlier patch by Tristan Madani. The Linux kernel CVE team has assigned CVE-2026-64079 to this issue. Affected and fixed versions =========================== Issue introduced in 5.13 with commit ae689334225ff0e4ef112459ecd24aea932c2b00 and fixed in 7.0.11 with commit 2f92c5f923979f37ab1d5445381e4b8378a196cc Issue introduced in 5.13 with commit ae689334225ff0e4ef112459ecd24aea932c2b00 and fixed in 7.1 with commit b62eb8dcf2c47d4d676a434efbd57c4f776f7829 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-2026-64079 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: include/linux/netfilter/x_tables.h net/ipv4/netfilter/arp_tables.c net/ipv4/netfilter/ip_tables.c net/ipv6/netfilter/ip6_tables.c net/netfilter/x_tables.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/2f92c5f923979f37ab1d5445381e4b8378a196cc https://git.kernel.org/stable/c/b62eb8dcf2c47d4d676a434efbd57c4f776f7829