diff options
| author | Davide Caratti <dcaratti@redhat.com> | 2020-05-27 02:04:26 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2020-05-27 11:11:18 -0700 |
| commit | bb2f930d6dd708469a587dc9ed1efe1ef969c0bf (patch) | |
| tree | 6abb7125a6f8708bc01b023af347ec28cf40d97d /net/sched | |
| parent | a4976a3ef844c510ae9120290b23e9f3f47d6bce (diff) | |
net/sched: fix infinite loop in sch_fq_pie
this command hangs forever:
# tc qdisc add dev eth0 root fq_pie flows 65536
watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [tc:1028]
[...]
CPU: 1 PID: 1028 Comm: tc Not tainted 5.7.0-rc6+ #167
RIP: 0010:fq_pie_init+0x60e/0x8b7 [sch_fq_pie]
Code: 4c 89 65 50 48 89 f8 48 c1 e8 03 42 80 3c 30 00 0f 85 2a 02 00 00 48 8d 7d 10 4c 89 65 58 48 89 f8 48 c1 e8 03 42 80 3c 30 00 <0f> 85 a7 01 00 00 48 8d 7d 18 48 c7 45 10 46 c3 23 00 48 89 f8 48
RSP: 0018:ffff888138d67468 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff9200018d2b2 RBX: ffff888139c1c400 RCX: ffffffffffffffff
RDX: 000000000000c5e8 RSI: ffffc900000e5000 RDI: ffffc90000c69590
RBP: ffffc90000c69580 R08: fffffbfff79a9699 R09: fffffbfff79a9699
R10: 0000000000000700 R11: fffffbfff79a9698 R12: ffffc90000c695d0
R13: 0000000000000000 R14: dffffc0000000000 R15: 000000002347c5e8
FS: 00007f01e1850e40(0000) GS:ffff88814c880000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000067c340 CR3: 000000013864c000 CR4: 0000000000340ee0
Call Trace:
qdisc_create+0x3fd/0xeb0
tc_modify_qdisc+0x3be/0x14a0
rtnetlink_rcv_msg+0x5f3/0x920
netlink_rcv_skb+0x121/0x350
netlink_unicast+0x439/0x630
netlink_sendmsg+0x714/0xbf0
sock_sendmsg+0xe2/0x110
____sys_sendmsg+0x5b4/0x890
___sys_sendmsg+0xe9/0x160
__sys_sendmsg+0xd3/0x170
do_syscall_64+0x9a/0x370
entry_SYSCALL_64_after_hwframe+0x44/0xa9
we can't accept 65536 as a valid number for 'nflows', because the loop on
'idx' in fq_pie_init() will never end. The extack message is correct, but
it doesn't say that 0 is not a valid number for 'flows': while at it, fix
this also. Add a tdc selftest to check correct validation of 'flows'.
CC: Ivan Vecera <ivecera@redhat.com>
Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/sch_fq_pie.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/net/sched/sch_fq_pie.c b/net/sched/sch_fq_pie.c index a9da8776bf5b..fb760cee824e 100644 --- a/net/sched/sch_fq_pie.c +++ b/net/sched/sch_fq_pie.c @@ -297,9 +297,9 @@ static int fq_pie_change(struct Qdisc *sch, struct nlattr *opt, goto flow_error; } q->flows_cnt = nla_get_u32(tb[TCA_FQ_PIE_FLOWS]); - if (!q->flows_cnt || q->flows_cnt > 65536) { + if (!q->flows_cnt || q->flows_cnt >= 65536) { NL_SET_ERR_MSG_MOD(extack, - "Number of flows must be < 65536"); + "Number of flows must range in [1..65535]"); goto flow_error; } } |