From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B0DE627A462; Thu, 15 Jan 2026 17:38:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768498687; cv=none; b=f4/o8xxZk6aK8vXwixjWJxdSoT7m0r1rW1FC+xq2j1FN/qt9Dskz4nYNXiJz8yokkBxOw7OsAM7CkDUFRTn5RNuAdB8Fs8ihEO6NFq6nNsVHNptyFk7xg15XrOhN/6CandGxanilQlhaT2gbb6qdc4c1WLNs3d1G5lQOiCydg2E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768498687; c=relaxed/simple; bh=jdJ4FhoJmKHvdngmQt0VBTYBfExCKZ2tlYSYrdZtUSk=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZHZSwRt8/mQvhay42cJuh3Azhp9RWK6S60P68aJX+kKVtlUyUwpTcjbIrLqtqFGrzDW5oq7hR2cL7gtl4PTzspun91U2ChdmCgX1LjmBcRaujdHHjPjD5Ur/stCniCZd0cGscTDWQNOXD3HZUqykCrCeqB9voXuEeiQLB5he2m0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=lSP0sYZZ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="lSP0sYZZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C0D5C116D0; Thu, 15 Jan 2026 17:38:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768498687; bh=jdJ4FhoJmKHvdngmQt0VBTYBfExCKZ2tlYSYrdZtUSk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lSP0sYZZlO0TTtf6tMEk35DsISVdtgAWIFqnSlzAOLfAJQ3UVlBK29VwkV+8o6miH zR6sMy2JvQQPtXmHstRaPhuDvDT1lP+vk7eossioMMA8N5EJqyHxeuOlrJf4d/Isaf 7l0Z9AUV4xPE9tMmsDzepORRi6AJcB48j9o7PjN4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Scott Mayhew , Benjamin Coddington , Trond Myklebust , Sasha Levin Subject: [PATCH 5.15 519/554] NFSv4: ensure the open stateid seqid doesnt go backwards Date: Thu, 15 Jan 2026 17:49:45 +0100 Message-ID: <20260115164305.112609997@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115164246.225995385@linuxfoundation.org> References: <20260115164246.225995385@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Scott Mayhew [ Upstream commit 2e47c3cc64b44b0b06cd68c2801db92ff143f2b2 ] We have observed an NFSv4 client receiving a LOCK reply with a status of NFS4ERR_OLD_STATEID and subsequently retrying the LOCK request with an earlier seqid value in the stateid. As this was for a new lockowner, that would imply that nfs_set_open_stateid_locked() had updated the open stateid seqid with an earlier value. Looking at nfs_set_open_stateid_locked(), if the incoming seqid is out of sequence, the task will sleep on the state->waitq for up to 5 seconds. If the task waits for the full 5 seconds, then after finishing the wait it'll update the open stateid seqid with whatever value the incoming seqid has. If there are multiple waiters in this scenario, then the last one to perform said update may not be the one with the highest seqid. Add a check to ensure that the seqid can only be incremented, and add a tracepoint to indicate when old seqids are skipped. Signed-off-by: Scott Mayhew Reviewed-by: Benjamin Coddington Signed-off-by: Trond Myklebust Signed-off-by: Sasha Levin --- fs/nfs/nfs4proc.c | 13 +++++++++++-- fs/nfs/nfs4trace.h | 1 + 2 files changed, 12 insertions(+), 2 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 883e4106fbcd9..cd97312860ce6 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1709,8 +1709,17 @@ static void nfs_set_open_stateid_locked(struct nfs4_state *state, if (nfs_stateid_is_sequential(state, stateid)) break; - if (status) - break; + if (status) { + if (nfs4_stateid_match_other(stateid, &state->open_stateid) && + !nfs4_stateid_is_newer(stateid, &state->open_stateid)) { + trace_nfs4_open_stateid_update_skip(state->inode, + stateid, status); + return; + } else { + break; + } + } + /* Rely on seqids for serialisation with NFSv4.0 */ if (!nfs4_has_session(NFS_SERVER(state->inode)->nfs_client)) break; diff --git a/fs/nfs/nfs4trace.h b/fs/nfs/nfs4trace.h index 8565fa654f59a..d3d5842781da2 100644 --- a/fs/nfs/nfs4trace.h +++ b/fs/nfs/nfs4trace.h @@ -1205,6 +1205,7 @@ DEFINE_NFS4_INODE_STATEID_EVENT(nfs4_setattr); DEFINE_NFS4_INODE_STATEID_EVENT(nfs4_delegreturn); DEFINE_NFS4_INODE_STATEID_EVENT(nfs4_open_stateid_update); DEFINE_NFS4_INODE_STATEID_EVENT(nfs4_open_stateid_update_wait); +DEFINE_NFS4_INODE_STATEID_EVENT(nfs4_open_stateid_update_skip); DEFINE_NFS4_INODE_STATEID_EVENT(nfs4_close_stateid_update_wait); DECLARE_EVENT_CLASS(nfs4_getattr_event, -- 2.51.0