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 90BCA3905F4; Fri, 4 Sep 2026 05:45:42 +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=1788500743; cv=none; b=XQ9z3aSamcW4Tx3Do6I4kLFR+JHeChuiYCao0Kx4ACwQDSWZPpi5fqXfKQpQoenIBswsbEQvPy77P3Lsx2v0cCUA3hQbcQI835ILkKiCYwz+kGKBnYgJu3Gn9xGJElG5Q11xEP13vbcecw83OLHMHlGKBItGGC/LtD3iNLkXjgM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788500743; c=relaxed/simple; bh=FwYEG+84gzF5Hg8AXYsHGR3b25gaPqEL0g7z4Vlyb/c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=RLyEijundacy3bJeAUuxDSt/dumBcTmXkl44GQaw7H+XUmorZdgNKWi3n07KvNXSOYU+SJfA9FYdDfVQYMLtTOq0AEzeAqXWKaU7M31UlzJyzioF6kDNCUgzVaCdPd7ZC01DLayGakQGRKJDqxJkxiK/86eHyuC0rzocVpmSgdg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=2L/gjhLt; 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="2L/gjhLt" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBB9E1F00A3D; Fri, 4 Sep 2026 05:45:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788500742; bh=TnUE/s3/Z3Cz74D8XvOXgn8oa+Y1EZqwCyGn1Qexgzo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=2L/gjhLtQpPQlNfx427WlOUd3B6VzZxHMRCiZbD3OsxTA0HK1CZXhJoaJIzKyKUgG WrNRZXt3FFRf1kt6AMdJe3krYBQ7nH+nzeD+bkPME3FwhDo5ibSxjTs0ZkyIlwyv8Z cnY0JrB3MjYVoHZYpJGjNvIHrN7ATMK5T/YkRyZ8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever Subject: [PATCH 6.18 121/552] nfsd: check client ownership when cancelling a copy-notify stateid Date: Fri, 4 Sep 2026 06:54:38 +0200 Message-ID: <20260904045750.814851343@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260904045747.813364717@linuxfoundation.org> References: <20260904045747.813364717@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit 6bdbfab96e0cf25e5f57dac5c09dc1749751a4bf upstream. On the OFFLOAD_CANCEL path (clp != NULL), manage_cpntf_state() freed the target cpntf state without checking ownership. The lookup key st->si_opaque.so_id is allocated cyclically (guessable) and the embedded clientid is the fixed per-net nn->s2s_cp_cl_id, so any authenticated NFSv4.2 client could cancel and free another client's copy-notify stateid. Compare the creating clientid recorded in state->cp_p_clid against the requesting client's cl_clientid and return nfserr_bad_stateid on a mismatch instead of freeing the entry. Fixes: ce0887ac96d3 ("NFSD add nfs4 inter ssc to nfsd4_copy") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260710-nfsd-testing-v3-5-a0ff7db6aa3e@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4state.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -7383,10 +7383,20 @@ __be32 manage_cpntf_state(struct nfsd_ne state = NULL; goto unlock; } - if (!clp) + if (!clp) { refcount_inc(&state->cp_stateid.cs_count); - else + } else if (memcmp(&clp->cl_clientid, &state->cp_p_clid, + sizeof(clientid_t))) { + /* + * OFFLOAD_CANCEL: only the creating client may cancel. + * so_id is guessable, so without this check any client + * could free another's cpntf state. + */ + state = NULL; + goto unlock; + } else { _free_cpntf_state_locked(nn, state); + } } unlock: spin_unlock(&nn->s2s_cp_lock);