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 C85AA319871; Fri, 10 Jul 2026 14:00:26 +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=1783692028; cv=none; b=u/vwp4KSXADurDQVOU4gyKM71pg7GeI49j4IIeAUXlo0BwIF5PFALVF2xklXDYnEW+y1XcDSkXFp3Kh8ttjGaXk9udogUnYJy+6aNm8P9lBQeL3FrPZkIRO8SyZsyRJInX+oaS6cjryTYpqbxfCHZjgzVdvQ0srd4YPDGs4Hymk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783692028; c=relaxed/simple; bh=GxJvjXtiR7eEOp06uNYPWPOn0UpTEVuLFO0Lu+rWrK8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=hfPcRRxJgQy5X4SoM6jRyzWYX7P4+xJ7BuaOtFZkxaXJMW0yD2uvwZGJa8oxBnteNumZtl7QPTw+WtHPYfaD3DeoD/gEIBsLZkvtjVZoSET5ACx0hUCNoaXtqO5/2LNzPFWKKakEV+3vLf5kC1uG1LtaoP6W+I0C3u55e1WQz/c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KzjLBZ0S; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KzjLBZ0S" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0CF8F1F00A3F; Fri, 10 Jul 2026 14:00:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783692026; bh=GGh4d/NZmelqfygPTYIZ7C/JabRyp9RVSEKvPbeIe8k=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=KzjLBZ0SQXMkDbeBm2tjBoOp7JV5rx4KSo73verZwe+F4d63KlE/VQVANRHb2d0ZY 0xgk7ecdJqeeM1g3fkpsb36cWIpAO95M2P4Hdy0VzCIeZAVFltof6NkGWnqC9lfGAO zSu1aRYlvHXeqAdfGIoSamkZ+9IwwmC94JAoeQgajwG4iMqgd7/+Ju00fsW2UBTqVP aHhAXYGho3ecGxKDuQyH8NqLaoDfMeDVDky1S59TAnynvnsl5omL8okdSNYyhqU7MN MPXDbWlDxFL5AbKvBjStiBGnvlSjNRe7poV7wJc4fYNzxrLq4Bsx6RiypQz+5dfCqU 2JxGloaHuBY5Q== From: Jeff Layton Date: Fri, 10 Jul 2026 10:00:09 -0400 Subject: [PATCH v3 05/10] nfsd: check client ownership when cancelling a copy-notify stateid Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260710-nfsd-testing-v3-5-a0ff7db6aa3e@kernel.org> References: <20260710-nfsd-testing-v3-0-a0ff7db6aa3e@kernel.org> In-Reply-To: <20260710-nfsd-testing-v3-0-a0ff7db6aa3e@kernel.org> To: Chuck Lever , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: Chris Mason , linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, Jeff Layton X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=1593; i=jlayton@kernel.org; h=from:subject:message-id; bh=GxJvjXtiR7eEOp06uNYPWPOn0UpTEVuLFO0Lu+rWrK8=; b=owEBbQKS/ZANAwAKAQAOaEEZVoIVAcsmYgBqUPrz/C27z01jVpmJHNwEOGOx8ru9fQipSnYRa +ma/d4TIRaJAjMEAAEKAB0WIQRLwNeyRHGyoYTq9dMADmhBGVaCFQUCalD68wAKCRAADmhBGVaC FcmTEACAeTIR6vhnaT+LYA1gFYTIB5MBBWTNoEUpTMBWzJCsO6lAeMZJASspEus6l+zvDRsiOAz ahLMPe9BFWMiyVuNvrcbjziLWLgWqINoC36ycVPON92McIsdG9kkrtvWydHpzlt2OKwKyWauFhX 5fUp1OFUINplWWX2B9dcPtgv+nW0EMsK+hLLBsyjUrXPD+sFhZgr6uRcWyDh6swO1oMiyXj7UUG 464LVJHHTDhemVzWHVii1rSSS+wj6G8LdDZxcZmgzbLEAk1dFWtumnNBzc5IrrGZQYr9xNAEhj2 seCGO8mEhhlBayhjk2zaez25xh0qmU1Vd+CWuDK/UAGSoeEB5+92A52PCZYWghvFLIgt5kBbFYF 3AUMukge6CQzYoGTBCiJU07V050MS4oQfEOJBT7miIfhyfGjg2orKDnL2YT2f6u1TOOYOELvyPo Zd8Vsi1wFVM/aDpoeSmTbsBc36b9KsXzKeE9k3KqGpmiImc5V/XwhlEKaZXVXtnWgnBCzLm7Xj8 VZ4uImCEKlxCT+FcryM787Gm4s9J+/6fyPI1FAg6u7gnT80T43RHeXd7Uh0au8CHGZJQFhrTqq2 78Mj2H8LzQOMwi9TnHR4Z3Fecf/BcxoHMnchSWbu3JrSJ9+Xoo1LRh9TpBmwNsHXOr9CZ7YQxwF 3W7HUPYsyuhCtCA== X-Developer-Key: i=jlayton@kernel.org; a=openpgp; fpr=4BC0D7B24471B2A184EAF5D3000E684119568215 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") Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton --- fs/nfsd/nfs4state.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 9ae0f18121ef..b3fe163a148d 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -7905,10 +7905,20 @@ __be32 manage_cpntf_state(struct nfsd_net *nn, stateid_t *st, 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); -- 2.55.0