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 D566746AEEA; Tue, 16 Jun 2026 15:58:18 +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=1781625499; cv=none; b=IZMbNU84v7ZGe3OuA/XyqNzmOlOa2eN+GphF6D4vcb5TwkVmAgofPuVbXzAotXBN4SNYsx093U77wTOQGhrq6I+vhaSSs7zY4k8U/rDwvv7neTdAjYqoSAf/sTgxiO0fZASYPKN13AF9nMP7WkJD3VnXV61igbKhcUDUhZYkCvI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781625499; c=relaxed/simple; bh=z2FpGc6HSgOHksXJnQWgnpB633a0eTE3+Gw48EnOasU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YEHA1Bdhh6TWvlcnXt7joFXJ6A6+1fUlqpMbytz8zdXNFACkVeRN916+M4GTgelbtGqtB5ChAsno1OPKIWz3Fzg9qAxPAJ/zd1iiD5r8pWoKF0RYqmPM5aeEJ4H4/+tkoQeGRthMNnLA+7L3P2WUx38hM2urNyxY6XsDugV8944= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HdeOFwzB; 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="HdeOFwzB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 887541F00A3D; Tue, 16 Jun 2026 15:58:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781625498; bh=G6eqeqWvMX8hx13b5PKmhg0tgWkNgnSk3ppVWYTXUtQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HdeOFwzBGEhUSv2qzJ6ShIKqRKqgub+BRU5L2IAOAtzArU/T0thpkbtUaiaKa7moW 3BzDrJe1x0XrMf7JMsle8EYroPtkcimm90ecsWYC4TBpXIQgev3H6KU/RMkxMjw86B KGj9AbauKYGq1X7jXxnUpC8hF6bUg2mRw1nRyx4A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Breno Leitao , Allison Henderson , Jakub Kicinski , Sasha Levin Subject: [PATCH 6.18 122/325] rds: mark snapshot pages dirty in rds_info_getsockopt() Date: Tue, 16 Jun 2026 20:28:38 +0530 Message-ID: <20260616145103.791167509@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145057.827196531@linuxfoundation.org> References: <20260616145057.827196531@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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Breno Leitao [ Upstream commit 512db8267b73a220a64180d95ab5eebe7c4964a8 ] 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 Reviewed-by: Allison Henderson Link: https://patch.msgid.link/20260608-rds_fix-v1-1-006c88543408@debian.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- 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 b6b46a8214a0a5..b3ee5f8238c44d 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; -- 2.53.0