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 606BA21ADC7 for ; Sat, 5 Sep 2026 11:02:47 +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=1788606171; cv=none; b=mMeR++0+3hlFa/6aaVCzMgV6748oDpeaTr89syWOa4GG63AzvVAx0D8dFZ/gP+E+HToXuGLfnLfqkzgfQVy92m+4BerQKw0BWrI7IiQhLRI9fCyQxcx2K0lBMDykHa3kp1LptLVQXRrsXzMTmxmqsFTnz/6EJa0FrEvlcV/EBKM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788606171; c=relaxed/simple; bh=Mr065B7/uPLPg1v+/pr7jCdffENTAzWagQN4dv5jq3M=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=pGLdubpS9kx1ZtoMCUjjcxs6m1G3zkfs/yGSQa09Ax1Hvkpmzty1WjS7ooZfftZ9IpFrONB6t49MXgYTKTdDm1kZRs9rvdHpkq8Ir2viiT6xWXhXwNwpxJtiJpGX26oHMBst22uTnxx9rt85jdr4OmNUhMJSMd/4dsvjPJODWPU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NQMysAQW; 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="NQMysAQW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EC48E1F00A3D; Sat, 5 Sep 2026 11:02:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788606167; bh=n4jBZaRhKqcOc67NiCuSyrhLsiNjR+Wil3PR0hNLZjo=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NQMysAQWBJMzSFKK9+g7eiEiuVBKHLbpbDcoql14h7nvGfc0lObvxr39dQKVciKdK 4vek5Hn4prmDURGRvsgT7QRIyEo5NIZcxtLnZGxrJBENiOJZR+5i6/1sW5kYoYHdan KOuF5My8FQRQw5CvLyZ3dR/U2zj/yEF8sg6i0xam0hwwPpjv0xHazmZuDZw9OAapZo j7MkWMYRdBDXTfJwFZ4HJBCxaNHPJ9ck1cb8yw8D16BvQwcwTP4P0w59TxFibBd6wS lAxOtES3uEd/f/INI+J3i3B7sjz9Fy6D6IDou7UsD7kxyjwMrryL35RAC9w8CKw/Ad 0XSc6CqMFmB1A== From: Sasha Levin To: stable@vger.kernel.org Cc: Jeff Layton , Chuck Lever , Sasha Levin Subject: [PATCH 6.18.y] nfsd: fix clock domain mismatch in clients_still_reclaiming() Date: Sat, 5 Sep 2026 07:02:45 -0400 Message-ID: <20260905110245.3661974-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <2026090314-hardcopy-exception-291b@gregkh> References: <2026090314-hardcopy-exception-291b@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Jeff Layton [ Upstream commit 09ea3eb9a518565f5bca386e81b993ed8825f5e8 ] clients_still_reclaiming() computes a deadline from nn->boot_time (CLOCK_REALTIME, ~1.7 billion) but compares it against ktime_get_boottime_seconds() (CLOCK_BOOTTIME, seconds since boot). The comparison is always false — it would take ~54 years of uptime for BOOTTIME to exceed the REALTIME-derived deadline. This means any client can hold the server in grace indefinitely by sending CLAIM_PREVIOUS OPEN requests, blocking all non-reclaim operations for all other clients. Add boot_time_bt (CLOCK_BOOTTIME) alongside the existing boot_time and use it for the deadline computation. boot_time (CLOCK_REALTIME) is preserved for its cl_boot clientid-nonce role. Fixes: 20b7d86f29d3 ("nfsd: use boottime for lease expiry calculation") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Jeff Layton Link: https://patch.msgid.link/20260611-nfsd-testing-v2-12-5b90e276f2d9@kernel.org Signed-off-by: Chuck Lever [ preserved the branch’s boolean fields instead of the upstream flags bitmap ] Signed-off-by: Sasha Levin --- fs/nfsd/netns.h | 1 + fs/nfsd/nfs4state.c | 3 ++- 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/nfsd/netns.h b/fs/nfsd/netns.h index fe8338735e7cc..ca25cfa4c36e2 100644 --- a/fs/nfsd/netns.h +++ b/fs/nfsd/netns.h @@ -69,6 +69,7 @@ struct nfsd_net { bool grace_end_forced; bool client_tracking_active; time64_t boot_time; + time64_t boot_time_bt; /* same instant in CLOCK_BOOTTIME */ struct dentry *nfsd_client_dir; diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index c9d9a7d46e7b2..9ab5135c052d9 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -6670,7 +6670,7 @@ bool nfsd4_force_end_grace(struct nfsd_net *nn) */ static bool clients_still_reclaiming(struct nfsd_net *nn) { - time64_t double_grace_period_end = nn->boot_time + + time64_t double_grace_period_end = nn->boot_time_bt + 2 * nn->nfsd4_lease; if (READ_ONCE(nn->grace_end_forced)) @@ -8993,6 +8993,7 @@ static int nfs4_state_create_net(struct net *net) nn->conf_name_tree = RB_ROOT; nn->unconf_name_tree = RB_ROOT; nn->boot_time = ktime_get_real_seconds(); + nn->boot_time_bt = ktime_get_boottime_seconds(); nn->grace_ended = false; nn->grace_end_forced = false; nn->client_tracking_active = false; -- 2.53.0