diff options
| author | Zhengchao Shao <shaozhengchao@huawei.com> | 2022-10-18 14:31:59 +0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2022-10-19 13:47:09 +0100 |
| commit | 51f9a8921ceacd7bf0d3f47fa867a64988ba1dcb (patch) | |
| tree | fe87a0804765a7eaa0462cba3c0944b8ed54d18b /net | |
| parent | 7b55c2ed2ba061b65fc51d7a18d37e017085997f (diff) | |
| download | linux-51f9a8921ceacd7bf0d3f47fa867a64988ba1dcb.tar.bz2 | |
net: sched: cake: fix null pointer access issue when cake_init() fails
When the default qdisc is cake, if the qdisc of dev_queue fails to be
inited during mqprio_init(), cake_reset() is invoked to clear
resources. In this case, the tins is NULL, and it will cause gpf issue.
The process is as follows:
qdisc_create_dflt()
cake_init()
q->tins = kvcalloc(...) --->failed, q->tins is NULL
...
qdisc_put()
...
cake_reset()
...
cake_dequeue_one()
b = &q->tins[...] --->q->tins is NULL
The following is the Call Trace information:
general protection fault, probably for non-canonical address
0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:cake_dequeue_one+0xc9/0x3c0
Call Trace:
<TASK>
cake_reset+0xb1/0x140
qdisc_reset+0xed/0x6f0
qdisc_destroy+0x82/0x4c0
qdisc_put+0x9e/0xb0
qdisc_create_dflt+0x2c3/0x4a0
mqprio_init+0xa71/0x1760
qdisc_create+0x3eb/0x1000
tc_modify_qdisc+0x408/0x1720
rtnetlink_rcv_msg+0x38e/0xac0
netlink_rcv_skb+0x12d/0x3a0
netlink_unicast+0x4a2/0x740
netlink_sendmsg+0x826/0xcc0
sock_sendmsg+0xc5/0x100
____sys_sendmsg+0x583/0x690
___sys_sendmsg+0xe8/0x160
__sys_sendmsg+0xbf/0x160
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f89e5122d04
</TASK>
Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
| -rw-r--r-- | net/sched/sch_cake.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c index 55c6879d2c7e..87f8ce2c65ee 100644 --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -2224,8 +2224,12 @@ retry: static void cake_reset(struct Qdisc *sch) { + struct cake_sched_data *q = qdisc_priv(sch); u32 c; + if (!q->tins) + return; + for (c = 0; c < CAKE_MAX_TINS; c++) cake_clear_tin(sch, c); } |