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 A3994477986; Tue, 16 Jun 2026 16:23:09 +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=1781626990; cv=none; b=PpGvDEWdwJ8Ebh1fPKZxO8GQC2Jtk8FV2+Tb5924TdtdYLHqi9kPJkVI1U2nvmiAadLUSaOfYdx8rVS4vN/jT8Mbunk3EuaS8g63P3pnD03SzMexcOcWTe2rinY3gQUW6O1wiLB2SB+9mAr3pvbTb1SHsbdm9WJ7AQA+7QfwoaQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781626990; c=relaxed/simple; bh=4Yc+JhDRInUeu6dMgSKtzIWH4gIKV0hxLeYZOYqDsvY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=k68VBsEYIS/7s/fsvyUPNt0/0IzCrF9KWEIDxrSMYIIoMIJc/zLhZq9b4E5ow4WiMhOq4nEFa4jCdiYT3SFpFB9bGqNPuXEjktKk82oM5PcaMMfFNndy2tMQiLAFROGG42RabvRFTkvl6HRLpso010M4soCkAKJGsQRP4zm/54k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AI/3Mloa; 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="AI/3Mloa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 69B521F000E9; Tue, 16 Jun 2026 16:23:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1781626989; bh=eisGFZfQ1s9ZxWl4Y0gSr0JuqbOdJroGDE8oJHGZ29g=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AI/3MloaXgvBII4WlJmmm27D5cn69fybfh+Ys6kEcqHXF/tf8OVLWiENxDAIv2lUC giu3CQ1ososUDIcMsUbtMMgkL8y3ChDxeT9ihOXukpkq5iIOV54JytcNdpkvz6WjJf L6kshqn/i1II2jrGy08b8GstGwlSLRH4BlHPx5so= 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 6.12 096/261] rds: mark snapshot pages dirty in rds_info_getsockopt() Date: Tue, 16 Jun 2026 20:28:54 +0530 Message-ID: <20260616145049.486279529@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260616145044.869532709@linuxfoundation.org> References: <20260616145044.869532709@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 6.12-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