From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from stravinsky.debian.org (stravinsky.debian.org [82.195.75.108]) (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 3821C2E739A; Mon, 8 Jun 2026 09:33:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=82.195.75.108 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780911215; cv=none; b=puJ0PiD3XyyEF2ZQSQ6awnwrp1AytBSHD2rtwIwOmSMWT553nm3EFO2mbHdJ7huIa+8jJREV1K//yL5FxTE7/03RWGkGfQIdBE03FeByTQwxC83XF9hcBJSP5LQ/XDHADfFxaSQKKgmE1WsMw25bf8URXJoSjKLqiaAeAYl4Tzg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780911215; c=relaxed/simple; bh=jXSbK/y3T0J/qL0JEnlkmOmsA9DHD/x5LY8yfr0d2tI=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:To:Cc; b=RMs4kkWC0Jbuhp9ONxuQz0onac6sbwS0IpIPunbvYxO1qEByWZNyK2TfILjsVv11q/hr5Q8cueadF2NBEYV3PbDeTptlwWY6576EXkgNRch1aWv6V2AI6eHmy5Bxpg2HVvsPmClKpfHHQXd1AaaQRuoMdNYL0wGASfJmQZlSfYo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org; spf=pass smtp.mailfrom=debian.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b=r++slE5y; arc=none smtp.client-ip=82.195.75.108 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=debian.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=debian.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=debian.org header.i=@debian.org header.b="r++slE5y" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=debian.org; s=smtpauto.stravinsky; h=X-Debian-User:Cc:To:Message-Id: Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date:From: Reply-To:Content-ID:Content-Description:In-Reply-To:References; bh=2536z80i2F49JQxoJ45J3DmC1kfjJnuOkkcVHn/LwUM=; b=r++slE5yJ6HlROhA2wjJvn/IqW ux9pU135kG6+NXjKumcCvjRZ0m+XzmEo0fQ0DGYY9U+uyxfvQK6zQrJTH81EkCsrY3Q0/fu6EOSqh Cl8tSvjhCvZu1Y/rrze4Vai3YAe4WaLk8tAZkciI6e9Qe/U+vWDrVge3h8tFnLx8B7cxRgMBxIhD9 0ovRodui0Lrt3D1Yd7TNEwEH+FDVhtBiYhlsw65hounOvf3M+MciIzZsae68ob5ri4mB5lLvhaO4e 1pkfVRW5WgdzHKvf3uW47EddSfRenWcEIuppihAFGcPgUVas6ENTl52ByDfkESySuh3/anOhrO3lI s2howo8w==; Received: from authenticated-user by stravinsky.debian.org with esmtpsa (TLS1.3:ECDHE_X25519__RSA_PSS_RSAE_SHA256__AES_256_GCM:256) (Exim 4.96) (envelope-from ) id 1wWWMJ-007WjY-1q; Mon, 08 Jun 2026 09:33:27 +0000 From: Breno Leitao Date: Mon, 08 Jun 2026 02:32:05 -0700 Subject: [PATCH net] rds: mark snapshot pages dirty in rds_info_getsockopt() Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260608-rds_fix-v1-1-006c88543408@debian.org> X-B4-Tracking: v=1; b=H4sIABSMJmoC/x3MUQqAIBAFwKss7zvBJKy8SkRErrU/FhoRiHcPm gNMQeYknOGoIPEjWc4IR21D2I417qzEwxGMNlZbPajk8xLkVaPxduuD7gIbNIQrcZD3nyZEvjH X+gGpqihWXgAAAA== X-Change-ID: 20260608-rds_fix-92d6c7f04fe2 To: Allison Henderson , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , Andy Grover Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-kernel@vger.kernel.org, kernel-team@meta.com, Breno Leitao X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=openpgp-sha256; l=1278; i=leitao@debian.org; h=from:subject:message-id; bh=jXSbK/y3T0J/qL0JEnlkmOmsA9DHD/x5LY8yfr0d2tI=; b=owEBbQKS/ZANAwAIATWjk5/8eHdtAcsmYgBqJoxjdwIHRloEIey/wH+093QB8dvjSgrE4ToW9 f51Vho4aOiJAjMEAAEIAB0WIQSshTmm6PRnAspKQ5s1o5Of/Hh3bQUCaiaMYwAKCRA1o5Of/Hh3 bXnrD/9Abi9ptLTHhISI6ZsdcLOArNcXEosMy6aGdfLb7IJ7aOMwLezl2Nyv91AxdO3/P8lg8Wv odoVcyADPuwPLR8uqGtjDRkxbW+AKascfYwacwNHDjhIeBFsl2nH54AKIog2IHFqxw5iVXItbyh Ujmkj0SofJ+IbWSiVLc70uUDcOe8X7nLLLGFZnitn+T/dSiaMEQifokCbv69WTIpd2Jhofa3NAV 8Gq9nXo1+iNbJo70BOwavQOgpq0wmxG55Q1+DPtGyGtLYucXGXWiphynXXsuA4ZU++5cKubQ5SR IixYPkdM6P9L2HS9fc53OMOLv6oF+NAy1tePEixaJTbAQPFrmCGveJXZ572ZV5bv6X+CaN6RF4G E7+Fxpq0A3lk6ABkC3VOCXl3UKJIUQ2kT3JqyGqVSPLV/lu3kxF1qF653ypqj8VOOb6AlthxeNR eXS2F0QJN3FpYa/yPePEj/TFooOn2mT/pP7Ddjs8LgA3xYVbED8VRNV2rGQVLphUzYUCn+n5l5h MFObDdVzHMnBOaHt5j/2jpIYj31YpZa3BuD12acxg2Cyc5aW2+iW7pG6a5jCy5wPlGx0CJ8s8mX BAiOI6Y0pltXUVCb447axaSv61vdjSCeEAt19nwvRAlXOTUmSEubAwYJyTd+8anraWKXZOQ67XV 7hEz4PF1YP0kInw== X-Developer-Key: i=leitao@debian.org; a=openpgp; fpr=AC8539A6E8F46702CA4A439B35A3939FFC78776D X-Debian-User: leitao rds_info_getsockopt() pins the destination user pages with FOLL_WRITE and the RDS_INFO_* producers memcpy the snapshot into them through kmap_atomic(). Because that copy goes through the kernel direct map, the dirty bit on the user PTE is never set, so unpin_user_pages() releases the pages without marking them dirty. A file-backed destination page can then be reclaimed without writeback, silently discarding the copied data. Use unpin_user_pages_dirty_lock() with make_dirty=true so the modified pages are marked dirty before they are unpinned. Fixes: a8c879a7ee98 ("RDS: Info and stats") Signed-off-by: Breno Leitao --- net/rds/info.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/rds/info.c b/net/rds/info.c index f1b29994934a..17061f6ff74e 100644 --- a/net/rds/info.c +++ b/net/rds/info.c @@ -235,7 +235,7 @@ int rds_info_getsockopt(struct socket *sock, int optname, char __user *optval, out: if (pages) - unpin_user_pages(pages, nr_pages); + unpin_user_pages_dirty_lock(pages, nr_pages, true); kfree(pages); return ret; --- base-commit: 9772589b57e44aedc240211c5c3f7a684a034d3a change-id: 20260608-rds_fix-92d6c7f04fe2 Best regards, -- Breno Leitao