From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794307995; b=3jDHs7uLa+LuAISZS9NcmGvFJbIETIiWr8TNWmiifxuKQHoMu1Go44YG1N0yhuolnp/c sRZH+GkbdAszzLutFY9XjA1qnAHpWEzlU9q44CndHeAX7uspaQOlIVGOz4nQr8JJ58Djv KTjXiuHZNnvZuSRz7/cqGANvinCHzt/cZ8+vgkPFEF2It05vCPrC5G3vl2hb7yRonf7Zk McG6lxcicYXz/r90/VcsJd8u22Q1AXkn5bSw1vzv2x9fTBZugj5hHcCbs3nKrnVQ0zAs2 y2Qz3EecuqhAuZtQ7y3IFGrjzg6T0CIdbdoG/KLrA4tzjvS3zsFhDGDQkifR02LerrA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794307995; h=Received:DKIM-Signature:Message-ID:From:Subject:Reply-To:To:Cc: In-Reply-To:References:Content-Type:Content-Transfer-Encoding:Date; bh=OADRfp/lToK0d62pH4PG6Qctpkt3Yy+E/djkgSCY54A=; b=Pf1BreaHBd8dQaaR2q9dUNeSvhHWmgEeei2BN3GI2BwaA8aj399rk4Gn55Y/0I15Ms6h W4sem7VjVqGcaTbbTmOa9oOP2TAe47Swzgb5/whSer/7Dtjhf9mYjpsp9faqpeg2Lav0x 9Ar2zuFTEV0aLqgKzALitjqRrVsVjnP0oM+4+Z02Mi1GCpbRRga3upN7unJXHoeY9p9rr ECYIsUmP2Ns1Tjmo53GQy70CsM47qfM0uwHY0ZsPWtxmvENaofR01HHe99FuDfaUjrQSl q87UwlHjsuPzeVcxysExa+FxWvXNZyGwuRBR4vALXr8HiFdvTh2YHQiy1j7JB4lGYqQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=iGSKozPv; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id CC1EA606A325 for ; Tue, 10 Nov 2026 10:53:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=iGSKozPv Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F6101F008A1; Tue, 10 Nov 2026 10:53:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794307994; bh=OADRfp/lToK0d62pH4PG6Qctpkt3Yy+E/djkgSCY54A=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=iGSKozPv0yoaQLhdDK8C0GIGFf8z3c9zd7FNKSm0KNahEzOiB76qjswTZoHFRmrMf VBcNetcciWV8gpS8EoF1MG7QMGaAiOh4Zs+x0vyvj1pibDvfRNy9IA+wma1XUyBIvB 5OR290QRP7xOdVefji9qg5JDrWsrdMbInvl40v214bJpN6ZnFxMTnbaThp4gqzXssY 7xzsv5IW4uYWige4HAnRozt3oU8MHpTt+Tk0Tkwt94xYu7H8falJ7Ago7Xgim5pZUh vP/kPnavEy8iR6PnPcDSdTcO0IB5dT/UngEtmmkx8sTLUUIdfKPw0/UVK4A8r1G1z3 kNl2LTUuE367Q== Message-ID: From: sashiko-bot@kernel.org Subject: Re: [PATCH 4/5] 9p: take the tag of a flushed request from the request Reply-To: sashiko-reviews@lists.linux.dev To: "Lianjie Wang" Cc: v9fs@lists.linux.dev In-Reply-To: <20261109105251.2545764-5-lian@is.s.u-tokyo.ac.jp> References: <20261109105251.2545764-1-lian@is.s.u-tokyo.ac.jp> <20261109105251.2545764-5-lian@is.s.u-tokyo.ac.jp> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 10 Nov 2026 10:53:13 +0000 X-Mailing-List: v9fs@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list > p9_client_flush() finds the tag of the request to cancel by parsing the > header of oldreq->tc. For a zero-copy TWRITE, however, > p9_virtio_zc_request() adds the payload length to the size in the header > after marshalling, so p9_parse_header() fails on the mismatch with > tc.size and no TFLUSH is sent. As a result, a zero-copy write > interrupted by a fatal signal returns without waiting for the RFLUSH, > and the server can still write the data after the writer is killed, > overwriting a later write to the same file. >=20 > Use the tag in oldreq->tc.tag and drop the parse, so a TFLUSH is sent. >=20 > This patch is assisted by Claude Opus 5.5. >=20 > Fixes: d28c756caee6 ("9p/net: Fix zero-copy path in the 9p virtio transpo= rt") > Cc: stable@vger.kernel.org > Signed-off-by: Lianjie Wang Sashiko has reviewed this patch and found no issues. --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261109105251.2545= 764-1-lian@is.s.u-tokyo.ac.jp?part=3D4