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 262FD363C55 for ; Sat, 22 Aug 2026 15:34:47 +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=1787412889; cv=none; b=HRFHgEeb4P2f538Ihp6iip9OWW5deJIojK5HhB5V1e1k60mfer6x4vLtQdbXrTOTvqwpqJRNRcU/dcO8/n7RXG3KK4YUwekAV6y1NOAAPLMw47VKPwlvp1qaB1JIdnCmcrcr3XSyl1bUkSl4RGiztDOV/UdET5lYyy8mxEkOVlw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787412889; c=relaxed/simple; bh=L08W+C4ICnsDAfV6AqiRmr8zgZEl/2loOsnh7Vnuzjo=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=RVsUkuxFcBdTHuXYMKK89fSSwY1p6D5ZXV0H6+dGZGKO2Z9T31t582OI2t4pE0S8ISuFW/lzlqmEd5l+GRRoOUHd3MPa3Aez2QRfuwMCuvCSEl8zz3GcWEHc5Z8fFHdDJq1TIBlQp/lIC19YiFlDwzIB9Ozm8yL1nSa54siwR44= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HcrCL2YF; 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="HcrCL2YF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 772571F000E9; Sat, 22 Aug 2026 15:34:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787412887; bh=d12R7pkUWQHUf3kfuAQGxRWTgGS1++FdvqQ9+gcJWhM=; h=From:To:Cc:Subject:Date:Reply-To; b=HcrCL2YFuBa9h/eNzRr8SUqNbpGVSBPFHt7RUARwrPXEvt7VY81WdvwMGkRl5VZEg AyF13wX2TsmoQLKvCgSNfe/3YQuiQmcApHpAVYB82YMBqHGMWxbHG2/Le1Vmamh7t1 d/jmpuS4dkHXDnVXv0HfjlhQ5ob8xWVsRhnr8xNQ= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-74590: fsverity: Fix bpf_get_fsverity_digest() dynptr assumptions Date: Sat, 22 Aug 2026 17:31:14 +0200 Message-ID: <2026082212-CVE-2026-74590-5358@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=2965; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=/ieknQozS0IsglLpSEP0Tb6w+4AUwPkvCWiQ1g5tU4Q=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmdBw6+DGu4eHz3bwHmrWEbKp9P/BK1YtOdQ8rCqy9zl Xc4qLet64hlYRBkYpAVU2T5so3n6P6KQ4pehranYeawMoEMYeDiFICJvL3MME+72Sg+pO5fp9Oh hwKhV2qsFyluP86woO9m+9TJfbZMioJy6l+SAosuxuctBAA= 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: fsverity: Fix bpf_get_fsverity_digest() dynptr assumptions The BPF verifier and the dynptr abstraction ensure that the memory space referenced by a dynptr remains valid. They do not, however, provide any guarantee that the contents of the memory are stable. kfuncs are expected to remain memory-safe even if concurrent modifications occur. bpf_get_fsverity_digest() didn't follow that: it could crash if arg->digest_size was concurrently modified. Fix that by using the known-good value hash_alg->digest_size instead. Also widen 'dynptr_sz' and 'out_digest_sz' to u64 to match the return type of __bpf_dynptr_size(). It doesn't appear that it can actually be more than INT_MAX currently (since __bpf_dynptr_data_rw() excludes file-based pointers), but the correct type might as well be used. The Linux kernel CVE team has assigned CVE-2026-74590 to this issue. Affected and fixed versions =========================== Issue introduced in 6.8 with commit 67814c00de3161181cddd06c77aeaf86ac4cc584 and fixed in 6.12.104 with commit 1344b632cb5043e32939a84568125719111c5af3 Issue introduced in 6.8 with commit 67814c00de3161181cddd06c77aeaf86ac4cc584 and fixed in 6.18.45 with commit 2a5cfcad1d56e26d645b7887b0ed24c371851525 Issue introduced in 6.8 with commit 67814c00de3161181cddd06c77aeaf86ac4cc584 and fixed in 7.1.9 with commit 5bd63cad9df4328a184c409fbdad4f17944bcdb8 Issue introduced in 6.8 with commit 67814c00de3161181cddd06c77aeaf86ac4cc584 and fixed in 7.2 with commit 3e8ec7c0387273329374f5c7bd61f5f38af71fe1 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-2026-74590 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: fs/verity/measure.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/1344b632cb5043e32939a84568125719111c5af3 https://git.kernel.org/stable/c/2a5cfcad1d56e26d645b7887b0ed24c371851525 https://git.kernel.org/stable/c/5bd63cad9df4328a184c409fbdad4f17944bcdb8 https://git.kernel.org/stable/c/3e8ec7c0387273329374f5c7bd61f5f38af71fe1