From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
syzbot+d5870a903591faaca4ae@syzkaller.appspotmail.com,
Linus Torvalds <torvalds@linux-foundation.org>,
Jamal Hadi Salim <jhs@mojatatu.com>,
Jiri Pirko <jiri@resnulli.us>,
Cong Wang <xiyou.wangcong@gmail.com>,
Jiri Pirko <jiri@mellanox.com>,
"David S. Miller" <davem@davemloft.net>
Subject: [PATCH 5.3 06/21] net_sched: let qdisc_put() accept NULL pointer
Date: Fri, 20 Sep 2019 00:03:07 +0200 [thread overview]
Message-ID: <20190919214701.920915648@linuxfoundation.org> (raw)
In-Reply-To: <20190919214657.842130855@linuxfoundation.org>
From: Cong Wang <xiyou.wangcong@gmail.com>
[ Upstream commit 6efb971ba8edfbd80b666f29de12882852f095ae ]
When tcf_block_get() fails in sfb_init(), q->qdisc is still a NULL
pointer which leads to a crash in sfb_destroy(). Similar for
sch_dsmark.
Instead of fixing each separately, Linus suggested to just accept
NULL pointer in qdisc_put(), which would make callers easier.
(For sch_dsmark, the bug probably exists long before commit
6529eaba33f0.)
Fixes: 6529eaba33f0 ("net: sched: introduce tcf block infractructure")
Reported-by: syzbot+d5870a903591faaca4ae@syzkaller.appspotmail.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/sched/sch_generic.c | 3 +++
1 file changed, 3 insertions(+)
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -985,6 +985,9 @@ static void qdisc_destroy(struct Qdisc *
void qdisc_put(struct Qdisc *qdisc)
{
+ if (!qdisc)
+ return;
+
if (qdisc->flags & TCQ_F_BUILTIN ||
!refcount_dec_and_test(&qdisc->refcnt))
return;
next prev parent reply other threads:[~2019-09-19 22:36 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-19 22:03 [PATCH 5.3 00/21] 5.3.1-stable review Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 01/21] USB: usbcore: Fix slab-out-of-bounds bug during device reset Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 02/21] media: tm6000: double free if usb disconnect while streaming Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 03/21] phy: renesas: rcar-gen3-usb2: Disable clearing VBUS in over-current Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 04/21] ip6_gre: fix a dst leak in ip6erspan_tunnel_xmit Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 05/21] net/sched: fix race between deactivation and dequeue for NOLOCK qdisc Greg Kroah-Hartman
2019-09-19 22:03 ` Greg Kroah-Hartman [this message]
2019-09-19 22:03 ` [PATCH 5.3 07/21] udp: correct reuseport selection with connected sockets Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 08/21] xen-netfront: do not assume sk_buff_head list is empty in error handling Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 09/21] net: dsa: Fix load order between DSA drivers and taggers Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 10/21] net: stmmac: Hold rtnl lock in suspend/resume callbacks Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 11/21] KVM: coalesced_mmio: add bounds checking Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 12/21] Documentation: sphinx: Add missing comma to list of strings Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 13/21] firmware: google: check if size is valid when decoding VPD data Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 14/21] serial: sprd: correct the wrong sequence of arguments Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 15/21] tty/serial: atmel: reschedule TX after RX was started Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 16/21] nl80211: Fix possible Spectre-v1 for CQM RSSI thresholds Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 17/21] Revert "arm64: Remove unnecessary ISBs from set_{pte,pmd,pud}" Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 18/21] ovl: fix regression caused by overlapping layers detection Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 19/21] phy: qcom-qmp: Correct ready status, again Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 20/21] floppy: fix usercopy direction Greg Kroah-Hartman
2019-09-19 22:03 ` [PATCH 5.3 21/21] media: technisat-usb2: break out of loop at end of buffer Greg Kroah-Hartman
2019-09-20 13:45 ` [PATCH 5.3 00/21] 5.3.1-stable review Guenter Roeck
2019-09-20 13:54 ` Jon Hunter
2019-09-20 14:24 ` Greg Kroah-Hartman
2019-09-20 16:01 ` Jon Hunter
2019-09-22 8:13 ` Greg Kroah-Hartman
2019-09-20 14:41 ` Naresh Kamboju
2019-09-21 5:06 ` Greg Kroah-Hartman
2019-09-20 21:17 ` shuah
2019-09-21 5:04 ` Greg Kroah-Hartman
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