Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753293Ab2HNWuX (ORCPT ); Tue, 14 Aug 2012 18:50:23 -0400 Received: from mga11.intel.com ([192.55.52.93]:42989 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751863Ab2HNWuW (ORCPT ); Tue, 14 Aug 2012 18:50:22 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.77,769,1336374000"; d="scan'208";a="208487016" From: John Fastabend Subject: [net PATCH v3 1/3] net: netprio: fix files lock and remove useless d_path bits To: viro@ZenIV.linux.org.uk, nhorman@tuxdriver.com Cc: netdev@vger.kernel.org, davem@davemloft.net, linux-kernel@vger.kernel.org, joe@perches.com Date: Tue, 14 Aug 2012 15:34:24 -0700 Message-ID: <20120814223424.3551.21608.stgit@jf-dev1-dcblab> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2075 Lines: 73 Add lock to prevent a race with a file closing and also remove useless and ugly sscanf code. The extra code was never needed and the case it supposedly protected against is in fact handled correctly by sock_from_file as pointed out by Al Viro. CC: Neil Horman Reported-by: Al Viro Signed-off-by: John Fastabend --- net/core/netprio_cgroup.c | 22 ++++------------------ 1 files changed, 4 insertions(+), 18 deletions(-) diff --git a/net/core/netprio_cgroup.c b/net/core/netprio_cgroup.c index ed0c043..f65dba3 100644 --- a/net/core/netprio_cgroup.c +++ b/net/core/netprio_cgroup.c @@ -277,12 +277,6 @@ out_free_devname: void net_prio_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) { struct task_struct *p; - char *tmp = kzalloc(sizeof(char) * PATH_MAX, GFP_KERNEL); - - if (!tmp) { - pr_warn("Unable to attach cgrp due to alloc failure!\n"); - return; - } cgroup_taskset_for_each(p, cgrp, tset) { unsigned int fd; @@ -296,32 +290,24 @@ void net_prio_attach(struct cgroup *cgrp, struct cgroup_taskset *tset) continue; } - rcu_read_lock(); + spin_lock(&files->file_lock); fdt = files_fdtable(files); for (fd = 0; fd < fdt->max_fds; fd++) { - char *path; struct file *file; struct socket *sock; - unsigned long s; - int rv, err = 0; + int err; file = fcheck_files(files, fd); if (!file) continue; - path = d_path(&file->f_path, tmp, PAGE_SIZE); - rv = sscanf(path, "socket:[%lu]", &s); - if (rv <= 0) - continue; - sock = sock_from_file(file, &err); - if (!err) + if (sock) sock_update_netprioidx(sock->sk, p); } - rcu_read_unlock(); + spin_unlock(&files->file_lock); task_unlock(p); } - kfree(tmp); } static struct cftype ss_files[] = { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/