* [PATCH for-4.4.y 1/5] sch_htb: fix crash on init failure
2018-07-31 18:43 [PATCH for-4.4.y 0/5] net/sched: init failure fixes Amit Pundir
@ 2018-07-31 18:43 ` Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 2/5] sch_multiq: fix double free " Amit Pundir
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Amit Pundir @ 2018-07-31 18:43 UTC (permalink / raw)
To: Greg KH, Nikolay Aleksandrov; +Cc: David S . Miller, Stable
From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
commit 88c2ace69dbef696edba77712882af03879abc9c upstream.
The commit below added a call to the ->destroy() callback for all qdiscs
which failed in their ->init(), but some were not prepared for such
change and can't handle partially initialized qdisc. HTB is one of them
and if any error occurs before the qdisc watchdog timer and qdisc work are
initialized then we can hit either a null ptr deref (timer->base) when
canceling in ->destroy or lockdep error info about trying to register
a non-static key and a stack dump. So to fix these two move the watchdog
timer and workqueue init before anything that can err out.
To reproduce userspace needs to send broken htb qdisc create request,
tested with a modified tc (q_htb.c).
Trace log:
[ 2710.897602] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 2710.897977] IP: hrtimer_active+0x17/0x8a
[ 2710.898174] PGD 58fab067
[ 2710.898175] P4D 58fab067
[ 2710.898353] PUD 586c0067
[ 2710.898531] PMD 0
[ 2710.898710]
[ 2710.899045] Oops: 0000 [#1] SMP
[ 2710.899232] Modules linked in:
[ 2710.899419] CPU: 1 PID: 950 Comm: tc Not tainted 4.13.0-rc6+ #54
[ 2710.899646] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 2710.900035] task: ffff880059ed2700 task.stack: ffff88005ad4c000
[ 2710.900262] RIP: 0010:hrtimer_active+0x17/0x8a
[ 2710.900467] RSP: 0018:ffff88005ad4f960 EFLAGS: 00010246
[ 2710.900684] RAX: 0000000000000000 RBX: ffff88003701e298 RCX: 0000000000000000
[ 2710.900933] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88003701e298
[ 2710.901177] RBP: ffff88005ad4f980 R08: 0000000000000001 R09: 0000000000000001
[ 2710.901419] R10: ffff88005ad4f800 R11: 0000000000000400 R12: 0000000000000000
[ 2710.901663] R13: ffff88003701e298 R14: ffffffff822a4540 R15: ffff88005ad4fac0
[ 2710.901907] FS: 00007f2f5e90f740(0000) GS:ffff88005d880000(0000) knlGS:0000000000000000
[ 2710.902277] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 2710.902500] CR2: 0000000000000000 CR3: 0000000058ca3000 CR4: 00000000000406e0
[ 2710.902744] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 2710.902977] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 2710.903180] Call Trace:
[ 2710.903332] hrtimer_try_to_cancel+0x1a/0x93
[ 2710.903504] hrtimer_cancel+0x15/0x20
[ 2710.903667] qdisc_watchdog_cancel+0x12/0x14
[ 2710.903866] htb_destroy+0x2e/0xf7
[ 2710.904097] qdisc_create+0x377/0x3fd
[ 2710.904330] tc_modify_qdisc+0x4d2/0x4fd
[ 2710.904511] rtnetlink_rcv_msg+0x188/0x197
[ 2710.904682] ? rcu_read_unlock+0x3e/0x5f
[ 2710.904849] ? rtnl_newlink+0x729/0x729
[ 2710.905017] netlink_rcv_skb+0x6c/0xce
[ 2710.905183] rtnetlink_rcv+0x23/0x2a
[ 2710.905345] netlink_unicast+0x103/0x181
[ 2710.905511] netlink_sendmsg+0x326/0x337
[ 2710.905679] sock_sendmsg_nosec+0x14/0x3f
[ 2710.905847] sock_sendmsg+0x29/0x2e
[ 2710.906010] ___sys_sendmsg+0x209/0x28b
[ 2710.906176] ? do_raw_spin_unlock+0xcd/0xf8
[ 2710.906346] ? _raw_spin_unlock+0x27/0x31
[ 2710.906514] ? __handle_mm_fault+0x651/0xdb1
[ 2710.906685] ? check_chain_key+0xb0/0xfd
[ 2710.906855] __sys_sendmsg+0x45/0x63
[ 2710.907018] ? __sys_sendmsg+0x45/0x63
[ 2710.907185] SyS_sendmsg+0x19/0x1b
[ 2710.907344] entry_SYSCALL_64_fastpath+0x23/0xc2
Note that probably this bug goes further back because the default qdisc
handling always calls ->destroy on init failure too.
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[AmitP: Rebased for linux-4.4.y]
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
net/sched/sch_htb.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 87b02ed3d5f2..daa01d5604c2 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1025,6 +1025,9 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt)
int err;
int i;
+ qdisc_watchdog_init(&q->watchdog, sch);
+ INIT_WORK(&q->work, htb_work_func);
+
if (!opt)
return -EINVAL;
@@ -1045,8 +1048,6 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt)
for (i = 0; i < TC_HTB_NUMPRIO; i++)
INIT_LIST_HEAD(q->drops + i);
- qdisc_watchdog_init(&q->watchdog, sch);
- INIT_WORK(&q->work, htb_work_func);
__skb_queue_head_init(&q->direct_queue);
if (tb[TCA_HTB_DIRECT_QLEN])
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH for-4.4.y 2/5] sch_multiq: fix double free on init failure
2018-07-31 18:43 [PATCH for-4.4.y 0/5] net/sched: init failure fixes Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 1/5] sch_htb: fix crash on init failure Amit Pundir
@ 2018-07-31 18:43 ` Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 3/5] sch_hhf: fix null pointer dereference " Amit Pundir
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Amit Pundir @ 2018-07-31 18:43 UTC (permalink / raw)
To: Greg KH, Nikolay Aleksandrov; +Cc: David S . Miller, Stable
From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
commit e89d469e3be3ed3d7124a803211a463ff83d0964 upstream.
The below commit added a call to ->destroy() on init failure, but multiq
still frees ->queues on error in init, but ->queues is also freed by
->destroy() thus we get double free and corrupted memory.
Very easy to reproduce (eth0 not multiqueue):
$ tc qdisc add dev eth0 root multiq
RTNETLINK answers: Operation not supported
$ ip l add dumdum type dummy
(crash)
Trace log:
[ 3929.467747] general protection fault: 0000 [#1] SMP
[ 3929.468083] Modules linked in:
[ 3929.468302] CPU: 3 PID: 967 Comm: ip Not tainted 4.13.0-rc6+ #56
[ 3929.468625] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 3929.469124] task: ffff88003716a700 task.stack: ffff88005872c000
[ 3929.469449] RIP: 0010:__kmalloc_track_caller+0x117/0x1be
[ 3929.469746] RSP: 0018:ffff88005872f6a0 EFLAGS: 00010246
[ 3929.470042] RAX: 00000000000002de RBX: 0000000058a59000 RCX: 00000000000002df
[ 3929.470406] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff821f7020
[ 3929.470770] RBP: ffff88005872f6e8 R08: 000000000001f010 R09: 0000000000000000
[ 3929.471133] R10: ffff88005872f730 R11: 0000000000008cdd R12: ff006d75646d7564
[ 3929.471496] R13: 00000000014000c0 R14: ffff88005b403c00 R15: ffff88005b403c00
[ 3929.471869] FS: 00007f0b70480740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000
[ 3929.472286] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3929.472677] CR2: 00007ffcee4f3000 CR3: 0000000059d45000 CR4: 00000000000406e0
[ 3929.473209] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 3929.474109] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 3929.474873] Call Trace:
[ 3929.475337] ? kstrdup_const+0x23/0x25
[ 3929.475863] kstrdup+0x2e/0x4b
[ 3929.476338] kstrdup_const+0x23/0x25
[ 3929.478084] __kernfs_new_node+0x28/0xbc
[ 3929.478478] kernfs_new_node+0x35/0x55
[ 3929.478929] kernfs_create_link+0x23/0x76
[ 3929.479478] sysfs_do_create_link_sd.isra.2+0x85/0xd7
[ 3929.480096] sysfs_create_link+0x33/0x35
[ 3929.480649] device_add+0x200/0x589
[ 3929.481184] netdev_register_kobject+0x7c/0x12f
[ 3929.481711] register_netdevice+0x373/0x471
[ 3929.482174] rtnl_newlink+0x614/0x729
[ 3929.482610] ? rtnl_newlink+0x17f/0x729
[ 3929.483080] rtnetlink_rcv_msg+0x188/0x197
[ 3929.483533] ? rcu_read_unlock+0x3e/0x5f
[ 3929.483984] ? rtnl_newlink+0x729/0x729
[ 3929.484420] netlink_rcv_skb+0x6c/0xce
[ 3929.484858] rtnetlink_rcv+0x23/0x2a
[ 3929.485291] netlink_unicast+0x103/0x181
[ 3929.485735] netlink_sendmsg+0x326/0x337
[ 3929.486181] sock_sendmsg_nosec+0x14/0x3f
[ 3929.486614] sock_sendmsg+0x29/0x2e
[ 3929.486973] ___sys_sendmsg+0x209/0x28b
[ 3929.487340] ? do_raw_spin_unlock+0xcd/0xf8
[ 3929.487719] ? _raw_spin_unlock+0x27/0x31
[ 3929.488092] ? __handle_mm_fault+0x651/0xdb1
[ 3929.488471] ? check_chain_key+0xb0/0xfd
[ 3929.488847] __sys_sendmsg+0x45/0x63
[ 3929.489206] ? __sys_sendmsg+0x45/0x63
[ 3929.489576] SyS_sendmsg+0x19/0x1b
[ 3929.489901] entry_SYSCALL_64_fastpath+0x23/0xc2
[ 3929.490172] RIP: 0033:0x7f0b6fb93690
[ 3929.490423] RSP: 002b:00007ffcee4ed588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 3929.490881] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f0b6fb93690
[ 3929.491198] RDX: 0000000000000000 RSI: 00007ffcee4ed5d0 RDI: 0000000000000003
[ 3929.491521] RBP: ffff88005872ff98 R08: 0000000000000001 R09: 0000000000000000
[ 3929.491801] R10: 00007ffcee4ed350 R11: 0000000000000246 R12: 0000000000000002
[ 3929.492075] R13: 000000000066f1a0 R14: 00007ffcee4f5680 R15: 0000000000000000
[ 3929.492352] ? trace_hardirqs_off_caller+0xa7/0xcf
[ 3929.492590] Code: 8b 45 c0 48 8b 45 b8 74 17 48 8b 4d c8 83 ca ff 44
89 ee 4c 89 f7 e8 83 ca ff ff 49 89 c4 eb 49 49 63 56 20 48 8d 48 01 4d
8b 06 <49> 8b 1c 14 48 89 c2 4c 89 e0 65 49 0f c7 08 0f 94 c0 83 f0 01
[ 3929.493335] RIP: __kmalloc_track_caller+0x117/0x1be RSP: ffff88005872f6a0
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: f07d1501292b ("multiq: Further multiqueue cleanup")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
net/sched/sch_multiq.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)
diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c
index bcdd54bb101c..e600a7e6e774 100644
--- a/net/sched/sch_multiq.c
+++ b/net/sched/sch_multiq.c
@@ -269,12 +269,7 @@ static int multiq_init(struct Qdisc *sch, struct nlattr *opt)
for (i = 0; i < q->max_bands; i++)
q->queues[i] = &noop_qdisc;
- err = multiq_tune(sch, opt);
-
- if (err)
- kfree(q->queues);
-
- return err;
+ return multiq_tune(sch, opt);
}
static int multiq_dump(struct Qdisc *sch, struct sk_buff *skb)
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH for-4.4.y 3/5] sch_hhf: fix null pointer dereference on init failure
2018-07-31 18:43 [PATCH for-4.4.y 0/5] net/sched: init failure fixes Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 1/5] sch_htb: fix crash on init failure Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 2/5] sch_multiq: fix double free " Amit Pundir
@ 2018-07-31 18:43 ` Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 4/5] sch_netem: avoid null pointer deref " Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 5/5] sch_tbf: fix two null pointer dereferences " Amit Pundir
4 siblings, 0 replies; 6+ messages in thread
From: Amit Pundir @ 2018-07-31 18:43 UTC (permalink / raw)
To: Greg KH, Nikolay Aleksandrov; +Cc: David S . Miller, Stable
From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
commit 32db864d33c21fd70a217ba53cb7224889354ffb upstream.
If sch_hhf fails in its ->init() function (either due to wrong
user-space arguments as below or memory alloc failure of hh_flows) it
will do a null pointer deref of q->hh_flows in its ->destroy() function.
To reproduce the crash:
$ tc qdisc add dev eth0 root hhf quantum 2000000 non_hh_weight 10000000
Crash log:
[ 690.654882] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 690.655565] IP: hhf_destroy+0x48/0xbc
[ 690.655944] PGD 37345067
[ 690.655948] P4D 37345067
[ 690.656252] PUD 58402067
[ 690.656554] PMD 0
[ 690.656857]
[ 690.657362] Oops: 0000 [#1] SMP
[ 690.657696] Modules linked in:
[ 690.658032] CPU: 3 PID: 920 Comm: tc Not tainted 4.13.0-rc6+ #57
[ 690.658525] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 690.659255] task: ffff880058578000 task.stack: ffff88005acbc000
[ 690.659747] RIP: 0010:hhf_destroy+0x48/0xbc
[ 690.660146] RSP: 0018:ffff88005acbf9e0 EFLAGS: 00010246
[ 690.660601] RAX: 0000000000000000 RBX: 0000000000000020 RCX: 0000000000000000
[ 690.661155] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffffff821f63f0
[ 690.661710] RBP: ffff88005acbfa08 R08: ffffffff81b10a90 R09: 0000000000000000
[ 690.662267] R10: 00000000f42b7019 R11: ffff880058578000 R12: 00000000ffffffea
[ 690.662820] R13: ffff8800372f6400 R14: 0000000000000000 R15: 0000000000000000
[ 690.663769] FS: 00007f8ae5e8b740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000
[ 690.667069] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 690.667965] CR2: 0000000000000000 CR3: 0000000058523000 CR4: 00000000000406e0
[ 690.668918] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 690.669945] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 690.671003] Call Trace:
[ 690.671743] qdisc_create+0x377/0x3fd
[ 690.672534] tc_modify_qdisc+0x4d2/0x4fd
[ 690.673324] rtnetlink_rcv_msg+0x188/0x197
[ 690.674204] ? rcu_read_unlock+0x3e/0x5f
[ 690.675091] ? rtnl_newlink+0x729/0x729
[ 690.675877] netlink_rcv_skb+0x6c/0xce
[ 690.676648] rtnetlink_rcv+0x23/0x2a
[ 690.677405] netlink_unicast+0x103/0x181
[ 690.678179] netlink_sendmsg+0x326/0x337
[ 690.678958] sock_sendmsg_nosec+0x14/0x3f
[ 690.679743] sock_sendmsg+0x29/0x2e
[ 690.680506] ___sys_sendmsg+0x209/0x28b
[ 690.681283] ? __handle_mm_fault+0xc7d/0xdb1
[ 690.681915] ? check_chain_key+0xb0/0xfd
[ 690.682449] __sys_sendmsg+0x45/0x63
[ 690.682954] ? __sys_sendmsg+0x45/0x63
[ 690.683471] SyS_sendmsg+0x19/0x1b
[ 690.683974] entry_SYSCALL_64_fastpath+0x23/0xc2
[ 690.684516] RIP: 0033:0x7f8ae529d690
[ 690.685016] RSP: 002b:00007fff26d2d6b8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 690.685931] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f8ae529d690
[ 690.686573] RDX: 0000000000000000 RSI: 00007fff26d2d700 RDI: 0000000000000003
[ 690.687047] RBP: ffff88005acbff98 R08: 0000000000000001 R09: 0000000000000000
[ 690.687519] R10: 00007fff26d2d480 R11: 0000000000000246 R12: 0000000000000002
[ 690.687996] R13: 0000000001258070 R14: 0000000000000001 R15: 0000000000000000
[ 690.688475] ? trace_hardirqs_off_caller+0xa7/0xcf
[ 690.688887] Code: 00 00 e8 2a 02 ae ff 49 8b bc 1d 60 02 00 00 48 83
c3 08 e8 19 02 ae ff 48 83 fb 20 75 dc 45 31 f6 4d 89 f7 4d 03 bd 20 02
00 00 <49> 8b 07 49 39 c7 75 24 49 83 c6 10 49 81 fe 00 40 00 00 75 e1
[ 690.690200] RIP: hhf_destroy+0x48/0xbc RSP: ffff88005acbf9e0
[ 690.690636] CR2: 0000000000000000
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
net/sched/sch_hhf.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/net/sched/sch_hhf.c b/net/sched/sch_hhf.c
index 45d4b2f22f62..aff2a1b46f7f 100644
--- a/net/sched/sch_hhf.c
+++ b/net/sched/sch_hhf.c
@@ -501,6 +501,9 @@ static void hhf_destroy(struct Qdisc *sch)
hhf_free(q->hhf_valid_bits[i]);
}
+ if (!q->hh_flows)
+ return;
+
for (i = 0; i < HH_FLOWS_CNT; i++) {
struct hh_flow_state *flow, *next;
struct list_head *head = &q->hh_flows[i];
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH for-4.4.y 4/5] sch_netem: avoid null pointer deref on init failure
2018-07-31 18:43 [PATCH for-4.4.y 0/5] net/sched: init failure fixes Amit Pundir
` (2 preceding siblings ...)
2018-07-31 18:43 ` [PATCH for-4.4.y 3/5] sch_hhf: fix null pointer dereference " Amit Pundir
@ 2018-07-31 18:43 ` Amit Pundir
2018-07-31 18:43 ` [PATCH for-4.4.y 5/5] sch_tbf: fix two null pointer dereferences " Amit Pundir
4 siblings, 0 replies; 6+ messages in thread
From: Amit Pundir @ 2018-07-31 18:43 UTC (permalink / raw)
To: Greg KH, Nikolay Aleksandrov; +Cc: David S . Miller, Stable
From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
commit 634576a1844dba15bc5e6fc61d72f37e13a21615 upstream.
netem can fail in ->init due to missing options (either not supplied by
user-space or used as a default qdisc) causing a timer->base null
pointer deref in its ->destroy() and ->reset() callbacks.
Reproduce:
$ sysctl net.core.default_qdisc=netem
$ ip l set ethX up
Crash log:
[ 1814.846943] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 1814.847181] IP: hrtimer_active+0x17/0x8a
[ 1814.847270] PGD 59c34067
[ 1814.847271] P4D 59c34067
[ 1814.847337] PUD 37374067
[ 1814.847403] PMD 0
[ 1814.847468]
[ 1814.847582] Oops: 0000 [#1] SMP
[ 1814.847655] Modules linked in: sch_netem(O) sch_fq_codel(O)
[ 1814.847761] CPU: 3 PID: 1573 Comm: ip Tainted: G O 4.13.0-rc6+ #62
[ 1814.847884] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 1814.848043] task: ffff88003723a700 task.stack: ffff88005adc8000
[ 1814.848235] RIP: 0010:hrtimer_active+0x17/0x8a
[ 1814.848407] RSP: 0018:ffff88005adcb590 EFLAGS: 00010246
[ 1814.848590] RAX: 0000000000000000 RBX: ffff880058e359d8 RCX: 0000000000000000
[ 1814.848793] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff880058e359d8
[ 1814.848998] RBP: ffff88005adcb5b0 R08: 00000000014080c0 R09: 00000000ffffffff
[ 1814.849204] R10: ffff88005adcb660 R11: 0000000000000020 R12: 0000000000000000
[ 1814.849410] R13: ffff880058e359d8 R14: 00000000ffffffff R15: 0000000000000001
[ 1814.849616] FS: 00007f733bbca740(0000) GS:ffff88005d980000(0000) knlGS:0000000000000000
[ 1814.849919] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1814.850107] CR2: 0000000000000000 CR3: 0000000059f0d000 CR4: 00000000000406e0
[ 1814.850313] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1814.850518] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 1814.850723] Call Trace:
[ 1814.850875] hrtimer_try_to_cancel+0x1a/0x93
[ 1814.851047] hrtimer_cancel+0x15/0x20
[ 1814.851211] qdisc_watchdog_cancel+0x12/0x14
[ 1814.851383] netem_reset+0xe6/0xed [sch_netem]
[ 1814.851561] qdisc_destroy+0x8b/0xe5
[ 1814.851723] qdisc_create_dflt+0x86/0x94
[ 1814.851890] ? dev_activate+0x129/0x129
[ 1814.852057] attach_one_default_qdisc+0x36/0x63
[ 1814.852232] netdev_for_each_tx_queue+0x3d/0x48
[ 1814.852406] dev_activate+0x4b/0x129
[ 1814.852569] __dev_open+0xe7/0x104
[ 1814.852730] __dev_change_flags+0xc6/0x15c
[ 1814.852899] dev_change_flags+0x25/0x59
[ 1814.853064] do_setlink+0x30c/0xb3f
[ 1814.853228] ? check_chain_key+0xb0/0xfd
[ 1814.853396] ? check_chain_key+0xb0/0xfd
[ 1814.853565] rtnl_newlink+0x3a4/0x729
[ 1814.853728] ? rtnl_newlink+0x117/0x729
[ 1814.853905] ? ns_capable_common+0xd/0xb1
[ 1814.854072] ? ns_capable+0x13/0x15
[ 1814.854234] rtnetlink_rcv_msg+0x188/0x197
[ 1814.854404] ? rcu_read_unlock+0x3e/0x5f
[ 1814.854572] ? rtnl_newlink+0x729/0x729
[ 1814.854737] netlink_rcv_skb+0x6c/0xce
[ 1814.854902] rtnetlink_rcv+0x23/0x2a
[ 1814.855064] netlink_unicast+0x103/0x181
[ 1814.855230] netlink_sendmsg+0x326/0x337
[ 1814.855398] sock_sendmsg_nosec+0x14/0x3f
[ 1814.855584] sock_sendmsg+0x29/0x2e
[ 1814.855747] ___sys_sendmsg+0x209/0x28b
[ 1814.855912] ? do_raw_spin_unlock+0xcd/0xf8
[ 1814.856082] ? _raw_spin_unlock+0x27/0x31
[ 1814.856251] ? __handle_mm_fault+0x651/0xdb1
[ 1814.856421] ? check_chain_key+0xb0/0xfd
[ 1814.856592] __sys_sendmsg+0x45/0x63
[ 1814.856755] ? __sys_sendmsg+0x45/0x63
[ 1814.856923] SyS_sendmsg+0x19/0x1b
[ 1814.857083] entry_SYSCALL_64_fastpath+0x23/0xc2
[ 1814.857256] RIP: 0033:0x7f733b2dd690
[ 1814.857419] RSP: 002b:00007ffe1d3387d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 1814.858238] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007f733b2dd690
[ 1814.858445] RDX: 0000000000000000 RSI: 00007ffe1d338820 RDI: 0000000000000003
[ 1814.858651] RBP: ffff88005adcbf98 R08: 0000000000000001 R09: 0000000000000003
[ 1814.858856] R10: 00007ffe1d3385a0 R11: 0000000000000246 R12: 0000000000000002
[ 1814.859060] R13: 000000000066f1a0 R14: 00007ffe1d3408d0 R15: 0000000000000000
[ 1814.859267] ? trace_hardirqs_off_caller+0xa7/0xcf
[ 1814.859446] Code: 10 55 48 89 c7 48 89 e5 e8 45 a1 fb ff 31 c0 5d c3
31 c0 c3 66 66 66 66 90 55 48 89 e5 41 56 41 55 41 54 53 49 89 fd 49 8b
45 30 <4c> 8b 20 41 8b 5c 24 38 31 c9 31 d2 48 c7 c7 50 8e 1d 82 41 89
[ 1814.860022] RIP: hrtimer_active+0x17/0x8a RSP: ffff88005adcb590
[ 1814.860214] CR2: 0000000000000000
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
net/sched/sch_netem.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index b7c29d5b6f04..743ff23885da 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -943,11 +943,11 @@ static int netem_init(struct Qdisc *sch, struct nlattr *opt)
struct netem_sched_data *q = qdisc_priv(sch);
int ret;
+ qdisc_watchdog_init(&q->watchdog, sch);
+
if (!opt)
return -EINVAL;
- qdisc_watchdog_init(&q->watchdog, sch);
-
q->loss_model = CLG_RANDOM;
ret = netem_change(sch, opt);
if (ret)
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH for-4.4.y 5/5] sch_tbf: fix two null pointer dereferences on init failure
2018-07-31 18:43 [PATCH for-4.4.y 0/5] net/sched: init failure fixes Amit Pundir
` (3 preceding siblings ...)
2018-07-31 18:43 ` [PATCH for-4.4.y 4/5] sch_netem: avoid null pointer deref " Amit Pundir
@ 2018-07-31 18:43 ` Amit Pundir
4 siblings, 0 replies; 6+ messages in thread
From: Amit Pundir @ 2018-07-31 18:43 UTC (permalink / raw)
To: Greg KH, Nikolay Aleksandrov; +Cc: David S . Miller, Stable
From: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
commit c2d6511e6a4f1f3673d711569c00c3849549e9b0 upstream.
sch_tbf calls qdisc_watchdog_cancel() in both its ->reset and ->destroy
callbacks but it may fail before the timer is initialized due to missing
options (either not supplied by user-space or set as a default qdisc),
also q->qdisc is used by ->reset and ->destroy so we need it initialized.
Reproduce:
$ sysctl net.core.default_qdisc=tbf
$ ip l set ethX up
Crash log:
[ 959.160172] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
[ 959.160323] IP: qdisc_reset+0xa/0x5c
[ 959.160400] PGD 59cdb067
[ 959.160401] P4D 59cdb067
[ 959.160466] PUD 59ccb067
[ 959.160532] PMD 0
[ 959.160597]
[ 959.160706] Oops: 0000 [#1] SMP
[ 959.160778] Modules linked in: sch_tbf sch_sfb sch_prio sch_netem
[ 959.160891] CPU: 2 PID: 1562 Comm: ip Not tainted 4.13.0-rc6+ #62
[ 959.160998] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 959.161157] task: ffff880059c9a700 task.stack: ffff8800376d0000
[ 959.161263] RIP: 0010:qdisc_reset+0xa/0x5c
[ 959.161347] RSP: 0018:ffff8800376d3610 EFLAGS: 00010286
[ 959.161531] RAX: ffffffffa001b1dd RBX: ffff8800373a2800 RCX: 0000000000000000
[ 959.161733] RDX: ffffffff8215f160 RSI: ffffffff8215f160 RDI: 0000000000000000
[ 959.161939] RBP: ffff8800376d3618 R08: 00000000014080c0 R09: 00000000ffffffff
[ 959.162141] R10: ffff8800376d3578 R11: 0000000000000020 R12: ffffffffa001d2c0
[ 959.162343] R13: ffff880037538000 R14: 00000000ffffffff R15: 0000000000000001
[ 959.162546] FS: 00007fcc5126b740(0000) GS:ffff88005d900000(0000) knlGS:0000000000000000
[ 959.162844] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 959.163030] CR2: 0000000000000018 CR3: 000000005abc4000 CR4: 00000000000406e0
[ 959.163233] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 959.163436] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 959.163638] Call Trace:
[ 959.163788] tbf_reset+0x19/0x64 [sch_tbf]
[ 959.163957] qdisc_destroy+0x8b/0xe5
[ 959.164119] qdisc_create_dflt+0x86/0x94
[ 959.164284] ? dev_activate+0x129/0x129
[ 959.164449] attach_one_default_qdisc+0x36/0x63
[ 959.164623] netdev_for_each_tx_queue+0x3d/0x48
[ 959.164795] dev_activate+0x4b/0x129
[ 959.164957] __dev_open+0xe7/0x104
[ 959.165118] __dev_change_flags+0xc6/0x15c
[ 959.165287] dev_change_flags+0x25/0x59
[ 959.165451] do_setlink+0x30c/0xb3f
[ 959.165613] ? check_chain_key+0xb0/0xfd
[ 959.165782] rtnl_newlink+0x3a4/0x729
[ 959.165947] ? rtnl_newlink+0x117/0x729
[ 959.166121] ? ns_capable_common+0xd/0xb1
[ 959.166288] ? ns_capable+0x13/0x15
[ 959.166450] rtnetlink_rcv_msg+0x188/0x197
[ 959.166617] ? rcu_read_unlock+0x3e/0x5f
[ 959.166783] ? rtnl_newlink+0x729/0x729
[ 959.166948] netlink_rcv_skb+0x6c/0xce
[ 959.167113] rtnetlink_rcv+0x23/0x2a
[ 959.167273] netlink_unicast+0x103/0x181
[ 959.167439] netlink_sendmsg+0x326/0x337
[ 959.167607] sock_sendmsg_nosec+0x14/0x3f
[ 959.167772] sock_sendmsg+0x29/0x2e
[ 959.167932] ___sys_sendmsg+0x209/0x28b
[ 959.168098] ? do_raw_spin_unlock+0xcd/0xf8
[ 959.168267] ? _raw_spin_unlock+0x27/0x31
[ 959.168432] ? __handle_mm_fault+0x651/0xdb1
[ 959.168602] ? check_chain_key+0xb0/0xfd
[ 959.168773] __sys_sendmsg+0x45/0x63
[ 959.168934] ? __sys_sendmsg+0x45/0x63
[ 959.169100] SyS_sendmsg+0x19/0x1b
[ 959.169260] entry_SYSCALL_64_fastpath+0x23/0xc2
[ 959.169432] RIP: 0033:0x7fcc5097e690
[ 959.169592] RSP: 002b:00007ffd0d5c7b48 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 959.169887] RAX: ffffffffffffffda RBX: ffffffff810d278c RCX: 00007fcc5097e690
[ 959.170089] RDX: 0000000000000000 RSI: 00007ffd0d5c7b90 RDI: 0000000000000003
[ 959.170292] RBP: ffff8800376d3f98 R08: 0000000000000001 R09: 0000000000000003
[ 959.170494] R10: 00007ffd0d5c7910 R11: 0000000000000246 R12: 0000000000000006
[ 959.170697] R13: 000000000066f1a0 R14: 00007ffd0d5cfc40 R15: 0000000000000000
[ 959.170900] ? trace_hardirqs_off_caller+0xa7/0xcf
[ 959.171076] Code: 00 41 c7 84 24 14 01 00 00 00 00 00 00 41 c7 84 24
98 00 00 00 00 00 00 00 41 5c 41 5d 41 5e 5d c3 66 66 66 66 90 55 48 89
e5 53 <48> 8b 47 18 48 89 fb 48 8b 40 48 48 85 c0 74 02 ff d0 48 8b bb
[ 959.171637] RIP: qdisc_reset+0xa/0x5c RSP: ffff8800376d3610
[ 959.171821] CR2: 0000000000000018
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Fixes: 0fbbeb1ba43b ("[PKT_SCHED]: Fix missing qdisc_destroy() in qdisc_create_dflt()")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
net/sched/sch_tbf.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
index c2fbde742f37..a06c9d6bfc9c 100644
--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -432,12 +432,13 @@ static int tbf_init(struct Qdisc *sch, struct nlattr *opt)
{
struct tbf_sched_data *q = qdisc_priv(sch);
+ qdisc_watchdog_init(&q->watchdog, sch);
+ q->qdisc = &noop_qdisc;
+
if (opt == NULL)
return -EINVAL;
q->t_c = ktime_get_ns();
- qdisc_watchdog_init(&q->watchdog, sch);
- q->qdisc = &noop_qdisc;
return tbf_change(sch, opt);
}
--
2.7.4
^ permalink raw reply related [flat|nested] 6+ messages in thread