blob: 5903dd007f869bfbf0e756fb2788832d8c276a9a [file] [log] [blame]
From 53b0f08042f04813cd1a7473dacd3edfacb28eb3 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Sat, 22 May 2010 20:37:44 +0000
Subject: net_sched: Fix qdisc_notify()
From: Eric Dumazet <eric.dumazet@gmail.com>
commit 53b0f08042f04813cd1a7473dacd3edfacb28eb3 upstream.
Ben Pfaff reported a kernel oops and provided a test program to
reproduce it.
https://kerneltrap.org/mailarchive/linux-netdev/2010/5/21/6277805
tc_fill_qdisc() should not be called for builtin qdisc, or it
dereference a NULL pointer to get device ifindex.
Fix is to always use tc_qdisc_dump_ignore() before calling
tc_fill_qdisc().
Reported-by: Ben Pfaff <blp@nicira.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
net/sched/sch_api.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -1195,6 +1195,11 @@ nla_put_failure:
return -1;
}
+static bool tc_qdisc_dump_ignore(struct Qdisc *q)
+{
+ return (q->flags & TCQ_F_BUILTIN) ? true : false;
+}
+
static int qdisc_notify(struct sk_buff *oskb, struct nlmsghdr *n,
u32 clid, struct Qdisc *old, struct Qdisc *new)
{
@@ -1205,11 +1210,11 @@ static int qdisc_notify(struct sk_buff *
if (!skb)
return -ENOBUFS;
- if (old && old->handle) {
+ if (old && !tc_qdisc_dump_ignore(old)) {
if (tc_fill_qdisc(skb, old, clid, pid, n->nlmsg_seq, 0, RTM_DELQDISC) < 0)
goto err_out;
}
- if (new) {
+ if (new && !tc_qdisc_dump_ignore(new)) {
if (tc_fill_qdisc(skb, new, clid, pid, n->nlmsg_seq, old ? NLM_F_REPLACE : 0, RTM_NEWQDISC) < 0)
goto err_out;
}
@@ -1222,11 +1227,6 @@ err_out:
return -EINVAL;
}
-static bool tc_qdisc_dump_ignore(struct Qdisc *q)
-{
- return (q->flags & TCQ_F_BUILTIN) ? true : false;
-}
-
static int tc_dump_qdisc_root(struct Qdisc *root, struct sk_buff *skb,
struct netlink_callback *cb,
int *q_idx_p, int s_q_idx)