summaryrefslogtreecommitdiffstats
path: root/net
diff options
context:
space:
mode:
authorTaehee Yoo <ap420073@gmail.com>2018-10-21 00:00:08 +0900
committerPablo Neira Ayuso <pablo@netfilter.org>2018-11-03 13:28:01 +0100
commit54451f60c8fa061af9051a53be9786393947367c (patch)
treef3cda53f6b4f0a5d7bd082db8b78828faabb244d /net
parent17b8b74c0f8dbf9b9e3301f9ca5b65dd1c079951 (diff)
downloadlinux-54451f60c8fa061af9051a53be9786393947367c.tar.bz2
netfilter: xt_IDLETIMER: add sysfs filename checking routine
When IDLETIMER rule is added, sysfs file is created under /sys/class/xt_idletimer/timers/ But some label name shouldn't be used. ".", "..", "power", "uevent", "subsystem", etc... So that sysfs filename checking routine is needed. test commands: %iptables -I INPUT -j IDLETIMER --timeout 1 --label "power" splat looks like: [95765.423132] sysfs: cannot create duplicate filename '/devices/virtual/xt_idletimer/timers/power' [95765.433418] CPU: 0 PID: 8446 Comm: iptables Not tainted 4.19.0-rc6+ #20 [95765.449755] Call Trace: [95765.449755] dump_stack+0xc9/0x16b [95765.449755] ? show_regs_print_info+0x5/0x5 [95765.449755] sysfs_warn_dup+0x74/0x90 [95765.449755] sysfs_add_file_mode_ns+0x352/0x500 [95765.449755] sysfs_create_file_ns+0x179/0x270 [95765.449755] ? sysfs_add_file_mode_ns+0x500/0x500 [95765.449755] ? idletimer_tg_checkentry+0x3e5/0xb1b [xt_IDLETIMER] [95765.449755] ? rcu_read_lock_sched_held+0x114/0x130 [95765.449755] ? __kmalloc_track_caller+0x211/0x2b0 [95765.449755] ? memcpy+0x34/0x50 [95765.449755] idletimer_tg_checkentry+0x4e2/0xb1b [xt_IDLETIMER] [ ... ] Fixes: 0902b469bd25 ("netfilter: xtables: idletimer target implementation") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net')
-rw-r--r--net/netfilter/xt_IDLETIMER.c20
1 files changed, 20 insertions, 0 deletions
diff --git a/net/netfilter/xt_IDLETIMER.c b/net/netfilter/xt_IDLETIMER.c
index c6acfc2d9c84..eb4cbd244c3d 100644
--- a/net/netfilter/xt_IDLETIMER.c
+++ b/net/netfilter/xt_IDLETIMER.c
@@ -114,6 +114,22 @@ static void idletimer_tg_expired(struct timer_list *t)
schedule_work(&timer->work);
}
+static int idletimer_check_sysfs_name(const char *name, unsigned int size)
+{
+ int ret;
+
+ ret = xt_check_proc_name(name, size);
+ if (ret < 0)
+ return ret;
+
+ if (!strcmp(name, "power") ||
+ !strcmp(name, "subsystem") ||
+ !strcmp(name, "uevent"))
+ return -EINVAL;
+
+ return 0;
+}
+
static int idletimer_tg_create(struct idletimer_tg_info *info)
{
int ret;
@@ -124,6 +140,10 @@ static int idletimer_tg_create(struct idletimer_tg_info *info)
goto out;
}
+ ret = idletimer_check_sysfs_name(info->label, sizeof(info->label));
+ if (ret < 0)
+ goto out_free_timer;
+
sysfs_attr_init(&info->timer->attr.attr);
info->timer->attr.attr.name = kstrdup(info->label, GFP_KERNEL);
if (!info->timer->attr.attr.name) {