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 9616F3BD22F for ; Mon, 20 Jul 2026 16:28:42 +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=1784564926; cv=none; b=LEQY56bStMDckvUwCFbsLTPfvX8fQoYTgY0m/IuYYHgKTB1dNT4yvkgWlD8BqQCKDVZFas03yND1ais2bXWlohzZC5qR8Yx3ahCHSSL+b8J4LXUf1R+lIl/v06EiT7zjd4RMpy0fPJUOK1Ob3emVkVPHnmz7exe91zAmd8GkXyQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784564926; c=relaxed/simple; bh=VfZNFeLFV99gpt7FFZR/88ERBTq3I5yhJiH5w+C9nS8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=jRv2D+e3zGRweC0yWIZminf8K2JveB6cLcdTmqMsH8TJuaJ/3uRV22YWTGEar2ygZGDIgvujTMiQmiYKdZt5aBumKrvHniy8r3SN8f8aLmhrECWvx/ym3vsFa3ArSCAjTWdUzWtbhoaf5Glap/yC5MjwPE3GXD8tyGt6LsxrL+4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=UIT37/Tv; 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="UIT37/Tv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 037AC1F00A3A; Mon, 20 Jul 2026 16:28:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784564919; bh=hqdgKaMbUkGNW4tvVB3owCXE5nB1qaU8JTAnZAyhqeE=; h=From:To:Cc:Subject:Date:Reply-To; b=UIT37/TvnJrhNxHfRq2cfHblwU9crRHcNBC6LgB1F4+yfmFUX9g4C0zP0PqsyN2j3 +z0sAijaXPeo+JbwMbexKuiB2lA/8S5lrmPaz2+uPGUF/kF2hUfmgEe0BmuVfy8/mg 78zL2Iqm1DB/x3np8Bk/KKnN5CG3G7Dqo48bvF4M= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-64192: bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized Date: Mon, 20 Jul 2026 18:27:55 +0200 Message-ID: <2026072052-CVE-2026-64192-8cd7@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=3397; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=Q/6L5Xy/xo+iyfqTUl+jwOiZuG8w80VjP6OxKs1jtc8=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlxPh0Nn6L317Mf7l977f/rK4sv7n7+0zExWnqZ0UXHp iMGt5596YhlYRBkYpAVU2T5so3n6P6KQ4pehranYeawMoEMYeDiFICJVAswzK+7e/j6X75PlUYs 6QrzH6ZtLTu9T45hfnWg/KQfOhZmBT+uVCkfUfAw9288CAA= 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: bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized When CONFIG_BPF_LSM=y is set, BPF inode storage maps (BPF_MAP_TYPE_INODE_STORAGE) are compiled into the kernel. However, if the BPF LSM is not explicitly enabled at boot time (e.g. omitted from the "lsm=" boot parameter), lsm_prepare() is never executed for the BPF LSM. Consequently, the BPF inode security blob offset (bpf_lsm_blob_sizes.lbs_inode) is never initialized and remains at its default compiled size of 8 bytes instead of being updated to a valid offset past the reserved struct rcu_head (typically 16 bytes or more). When a privileged user creates and updates a BPF_MAP_TYPE_INODE_STORAGE map, bpf_inode() evaluates inode->i_security + 8. This erroneously aliases the struct rcu_head.func callback pointer at the beginning of the inode->i_security blob. During subsequent map element cleanup or inode destruction, writing NULL to owner_storage clears the queued RCU callback pointer. When rcu_do_batch() later executes the queued callback, it attempts an instruction fetch at address 0x0, triggering an immediate kernel panic. Fix this by introducing a global bpf_lsm_initialized boolean flag marked with __ro_after_init. Set this flag to true inside bpf_lsm_init() when the LSM framework successfully registers the BPF LSM. Gate map allocation in inode_storage_map_alloc() on this flag, returning -EOPNOTSUPP if the BPF LSM is in turn uninitialized. This fail-fast approach prevents userspace from allocating inode storage maps when the supporting BPF LSM infrastructure is absent, avoiding zombie map states. The Linux kernel CVE team has assigned CVE-2026-64192 to this issue. Affected and fixed versions =========================== Issue introduced in 5.10 with commit 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 and fixed in 7.1.4 with commit c76b8abce575e0c6e4096957220b4515ed847d89 Issue introduced in 5.10 with commit 8ea636848aca35b9f97c5b5dee30225cf2dd0fe6 and fixed in 7.2-rc2 with commit a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4 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-2026-64192 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/bpf_lsm.h kernel/bpf/bpf_inode_storage.c security/bpf/hooks.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/c76b8abce575e0c6e4096957220b4515ed847d89 https://git.kernel.org/stable/c/a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4