From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.138 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792640235; b=UEV71fXwmbH19rJQQ2XyZScvrXY91Tuf+4K9dgiC4YxXcalLfRCG3KQ1PSA0CzvB9JS9 fGyV3mxIGaSRmHItGnWSkdElMk7S245BMx1lARpSuRMLTS6ON4O0icE0KldnMbAv5lDy+ Bego6ZxVXwt42zNvVV64lmweexcFkQv4bwO0rpyRIHBt2gHP0g2NJLdDosxa9CR78mrpr kD5/1wZE/VcUdQraCVgVZPgG4S9lPpMH+r+lnktqCvdh9eR89Okx81hpC5TJ5ZQZcmsS0 8gffFEu8d7L4fqqEQJ4r/22TB6qcm3oGi8KYEFomuiIFcun24nAYpDlf9QndY8l4H9g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792640235; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Message-ID:Date:MIME-Version:User-Agent: Subject:To:References:From:In-Reply-To:Content-Type: Content-Transfer-Encoding; bh=mgKk29cEMPjhkL/nlf6+/Mbk4gVlKk12lMtS/g48E/Y=; b=5mwTnAuQS4azQI1jzCqFqPwP5ZWxplPPwBna3LdUZaFITnnwYGZoOOC9qm07N8A37mo8 kq9KB471WciyEypICiJCSpxkx3FZgei+VSZ/bK63yBg+7yzWOYJK8F+V4vd+QxIrVzepr cLPRi1w12tpCgZNXnEKs90dO1m7e4g0S+aP5hVl7QYDZ2wWOq6IsecbU/TMHA9fgAIsB3 VYm6q24+fQSNVRQg4DGG5NdtmUCty7Z/MpLJF5/X1UA7ONsi2zWU31nCs/EJ2Ldp2DmfR +JjIXFVKsK1csthgMdBtHnRqCkaMWriEvtIVYG3kk4WBlTgcQSjBqT2WreeM2jXcPjQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=pPKMCILm; arc=none smtp.remote-ip=95.215.58.138 Received: from mta1.migadu.com (out-138.mta1.migadu.com [95.215.58.138]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F281606A319 for ; Thu, 22 Oct 2026 03:37:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 7F281606A319 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=pPKMCILm X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=v/+HvHqCDL8KYF8wOBFc643AIKQ4/I0Ny3wDaVlxt+E=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792640232; v=1; x=1793245032; b=pPKMCILmja6Z+PWBaYW7Eo7OZuyOR4KCx329VPpB251MHNPXPiQlV8fqD2mrk9qG3WQMtpaJ ses3l/V5Y0XIm8z3OF0q6vt+ImzMHFUMiGlUcf5Uq0dy3VC3qt39MVtHuBYk+nW4PZYXAq+EG88 tvllewqy1caWKwXOPXYky3ic= X-Envelope-To: bpf@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id 75c4dd5b6378d2f3; Thu, 22 Oct 2026 03:37:12 +0000 X-Mizu-Trace-ID: 75c4dd5b6378d2f3 X-Migadu-Flow: FLOW_OUT Message-ID: Date: Thu, 22 Oct 2026 11:37:10 +0800 X-Mailing-List: bpf@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH bpf] bpf, sockmap: use READ_ONCE/WRITE_ONCE for saved_data_ready in the verdict path To: bpf@vger.kernel.org References: <20261021155629.68813-1-phx0fer@gmail.com> From: Jiayuan Chen In-Reply-To: <20261021155629.68813-1-phx0fer@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 10/21/26 11:56 PM, Dudu Lu wrote: > sk_psock_start_verdict() and sk_psock_stop_verdict() access > psock->saved_data_ready with plain loads and stores, while the sibling > sk_psock_stop_strp() uses WRITE_ONCE for the same field. sock_map_link() > / sock_map_unref() touch the same psock from another CPU without the > lock, so KCSAN reports the race: > > BUG: KCSAN: data-race in sock_map_link / sock_map_unref > BUG: KCSAN: data-race in sk_psock_start_verdict / sock_map_unref > > Use READ_ONCE() for the reads and WRITE_ONCE() for the writes, matching > the strp sibling. > > Fixes: 2ef2b20cf4e0 ("net: annotate data-races around sk->sk_{data_ready,write_space}") I think it's just an incomplete fix which you shouldn't  blame.