From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.manguebit.org (mx1.manguebit.org [143.255.12.172]) (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 75BDC4B95B3; Mon, 21 Sep 2026 15:50:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=143.255.12.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790005813; cv=none; b=emm1MDSSGIgY5V/R6uW9V6iYt9zkXYcCZwflGimt6IL+gHwDPmVeVPFv54Z+krxOP/Un4gUDQhnzVtwpH3+WpbbTSXuwHzROmeIweybxuwoqxCiquW9Kb9cUCyoSZewONsBjTeCnhPRvYG6yV4Dgfm55rzuLKXvOZGViJDsWVBc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790005813; c=relaxed/simple; bh=mO1Q6o/KgWEmLo/X5UeOaKF3RGYwnhN8kQubbqxYmOE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=h9oTlAkXoZhcUHTxlD3XigvLmVviatWTu9c+ebkvaE+ovLjSSFaNnqIVFTB3NQjLl4aWs+VfR26fqo6JGtB4Wd6jvVCoRqs0TY9viQOlO0W8sVAiMqoDKFQoqxVbLC1knlzpLVULc7fF6GAH+z4EPLd0kZIP3kj0qmY1ghuNgcE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=manguebit.org; spf=pass smtp.mailfrom=manguebit.org; dkim=pass (2048-bit key) header.d=manguebit.org header.i=@manguebit.org header.b=BSCLespp; arc=none smtp.client-ip=143.255.12.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=manguebit.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=manguebit.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=manguebit.org header.i=@manguebit.org header.b="BSCLespp" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=manguebit.org; s=dkim; h=Content-Transfer-Encoding:MIME-Version:References: In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Content-Type:Reply-To: Content-ID:Content-Description; bh=Qu3yhx/bEbobPer+L/YgEZ1ItCwhUqJNwO8CbwoEukM=; b=BSCLespp+AeCHIL94CaA3qLJoU kpXRccxPV17c0773DZFwK9Y2hwlGroYKewb8VJNMegPfCtILY1yEfwLEtt//JlYIm2kdysXcwr4L3 CALlqeOh9qYyJAiGnvruY9N4zN9hafQeNlhCvKNsVzuALWxTrLFptvCni2silOfiiQa+OY0bs+FEg 5efeNEMur1BF39trzzZ6TYDT71SOl/U1gf71DON9G3QjMOS7gx041QFbUleX9d/FCk2V0/rYYCtt2 vKmeXczj2rX3PJ564tWWxHCBxGziNwQ4ZFYbYvofeOfSnX/AX2ZrT0QdCzIC6Ky9iLC2hCB6i0zM1 Wlqq8VaQ==; Received: from pc by mx1.manguebit.org with local (Exim 4.99.5) id 1x8gHH-00000001wCI-2Ld7; Mon, 21 Sep 2026 12:49:59 -0300 From: Paulo Alcantara To: linux-cifs@vger.kernel.org, netfs@lists.linux.dev Cc: David Howells , Christian Brauner , Namjae Jeon , Ronnie Sahlberg , Shyam Prasad N , Tom Talpey , Bharath SM , stable@vger.kernel.org Subject: [PATCH 4/5] smb: client: discard post-EOF pagecache when extending a file via copy range Date: Mon, 21 Sep 2026 12:49:56 -0300 Message-ID: <20260921154957.903891-4-pc@manguebit.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260921154957.903891-1-pc@manguebit.org> References: <20260921154957.903891-1-pc@manguebit.org> Precedence: bulk X-Mailing-List: netfs@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit cifs_file_copychunk_range() invalidated the pagecache only for the destination region, so when a copy extends the file the folio straddling the old EOF - which may hold data dirtied past EOF through an mmap - was never dropped and became visible as file content once the file was extended. Start the invalidation at the smaller of the destination offset and the old EOF. filemap_invalidate_inode() writes back before invalidating while i_size is still old, so nothing past the old EOF is flushed to the server. Fixes: 8101d6e112e2 ("cifs: Fix copy offload to flush destination region") Reviewed-by: David Howells Signed-off-by: Paulo Alcantara Cc: Christian Brauner Cc: Namjae Jeon Cc: Ronnie Sahlberg Cc: Shyam Prasad N Cc: Tom Talpey Cc: Bharath SM Cc: stable@vger.kernel.org --- fs/smb/client/cifsfs.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/smb/client/cifsfs.c b/fs/smb/client/cifsfs.c index 7ecd70efdfea..f1fb4b7b7b7c 100644 --- a/fs/smb/client/cifsfs.c +++ b/fs/smb/client/cifsfs.c @@ -1581,8 +1581,13 @@ ssize_t cifs_file_copychunk_range(unsigned int xid, /* Flush and invalidate all the folios in the destination region. If * the copy was successful, then some of the flush is extra overhead, * but we need to allow for the copy failing in some way (eg. ENOSPC). + * + * Start at the old EOF when extending so the folio straddling it, which + * may hold data written past EOF through an mmap, is dropped too. */ - rc = filemap_invalidate_inode(target_inode, true, destoff, destoff + len - 1); + rc = filemap_invalidate_inode(target_inode, true, + min(destoff, i_size_read(target_inode)), + destoff + len - 1); if (rc) goto unlock; -- 2.55.0