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 DE5134BEE3C; Sat, 12 Sep 2026 17:06:15 +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=1789232777; cv=none; b=Df47M94FpICg9icRdptzFVX/eLXPEBRdvCraXgzZVrOhLyIaZSgqqO2fsUoB5fEvGakcYGMBOJwcXCUbzIfAHJBejEqn6TgODarRVDDuTdCGQj/a/oFb/pp5jQcpd6BXpQ/bZEMMRY/fa8/IzZ5d2HuCXdNP962fCymh83ustTw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789232777; c=relaxed/simple; bh=WiKiQLnMJ/LnjeYcXoZbWXc1Afim6WTsWdJQsJqGToI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hW3pe/zQR6SYo2vQYd4gbdp3Ezzp3l+FWZUFaBV56Cx6rcblhw1MVKHpG+bsILJFdvyt8J9c/q7/KeI7YxcSyrPhy/HAGmVyJLvj4RxD4AZLW8OnYxwrJ34lLwOKmQ0oRtpHfHMcLyZsClDRgstSZzwtbFwkYfZPk185mg9nNuA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Aa0jvOnH; 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="Aa0jvOnH" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E307C1F000FF; Sat, 12 Sep 2026 17:06:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789232775; bh=SK4mmu0xUAYDQ+jXegUfttABH45jPG2JCgh/jkRb5sk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Aa0jvOnHTazY46QtB8NxWM0JNu9Ank/jCOESXyfqgKMK5wefNl8s06d0GSmRF9KRb 6NDr/y791n0OytHTAWlSoT22PEbOHgolo+EVAq5Ze+2FYa2hmZXhlRESuX4s5f6MG1 Fo0mOLQzdXAmTJ/NZI4PLyBMNlVM0x4lm0qWri5A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever Subject: [PATCH 5.15 036/935] nfsd: Reset write verifier when async COPY writeback fails Date: Sat, 12 Sep 2026 08:51:06 +0200 Message-ID: <20260912065527.668149993@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065526.833703348@linuxfoundation.org> References: <20260912065526.833703348@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever commit f5cb2276954cb80987a93ef9f9dfbfdbfc0f10b9 upstream. Async COPY captures nn->writeverf at request time and reports it to the client via CB_OFFLOAD after the worker kthread completes. When the post-copy vfs_fsync_range() or filemap_check_wb_err() in _nfsd_copy_file_range() reports an error, the worker correctly leaves NFSD4_COPY_F_COMMITTED clear so that CB_OFFLOAD encodes wr_stable_how as NFS_UNSTABLE, but the server's write verifier is not rotated. A client that receives NFS_UNSTABLE in CB_OFFLOAD follows up with COMMIT to make the copied data durable. With the verifier unchanged, COMMIT returns the same value the client just received via CB_OFFLOAD, and the client concludes the copy is durable -- silently dropping the data whose writeback in fact failed. This violates the UNSTABLE+COMMIT durability contract (RFC 7862 section 15.1, RFC 8881 section 18.32) and matches the bug just fixed in nfsd_vfs_write() and nfsd_commit(). Rotate nn->writeverf at the writeback-failure site. The async COPY worker has no svc_rqst, so commit_reset_write_verifier() is not available here; calling nfsd_reset_write_verifier() directly mirrors the trace-less reset already used by nfsd_file_check_write_error() for the same purpose. Filter out -EAGAIN and -ESTALE, matching commit_reset_write_verifier(), since neither indicates a durable-storage failure. Fixes: eac0b17a77fb ("NFSD add vfs_fsync after async copy is done") Cc: stable@vger.kernel.org Assisted-by: kres:claude-opus-4-7 Reviewed-by: Jeff Layton Link: https://patch.msgid.link/20260522203723.446841-1-cel@kernel.org Signed-off-by: Chuck Lever Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/nfs4proc.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1628,6 +1628,8 @@ static ssize_t _nfsd_copy_file_range(str status = filemap_check_wb_err(dst->f_mapping, since); if (!status) set_bit(NFSD4_COPY_F_COMMITTED, ©->cp_flags); + else if (status != -EAGAIN && status != -ESTALE) + nfsd_reset_write_verifier(copy->cp_nn); } return bytes_copied; }