From 09d4f10a5e78d76a53e3e584f1e6a701b6d24108 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Sat, 18 Jan 2020 20:45:06 -0800 Subject: [PATCH] net: sched: act_ctinfo: fix memory leak MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Implement a cleanup method to properly free ci->params BUG: memory leak unreferenced object 0xffff88811746e2c0 (size 64): comm "syz-executor617", pid 7106, jiffies 4294943055 (age 14.250s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ c0 34 60 84 ff ff ff ff 00 00 00 00 00 00 00 00 .4`............. backtrace: [<0000000015aa236f>] kmemleak_alloc_recursive include/linux/kmemleak.h:43 [inline] [<0000000015aa236f>] slab_post_alloc_hook mm/slab.h:586 [inline] [<0000000015aa236f>] slab_alloc mm/slab.c:3320 [inline] [<0000000015aa236f>] kmem_cache_alloc_trace+0x145/0x2c0 mm/slab.c:3549 [<000000002c946bd1>] kmalloc include/linux/slab.h:556 [inline] [<000000002c946bd1>] kzalloc include/linux/slab.h:670 [inline] [<000000002c946bd1>] tcf_ctinfo_init+0x21a/0x530 net/sched/act_ctinfo.c:236 [<0000000086952cca>] tcf_action_init_1+0x400/0x5b0 net/sched/act_api.c:944 [<000000005ab29bf8>] tcf_action_init+0x135/0x1c0 net/sched/act_api.c:1000 [<00000000392f56f9>] tcf_action_add+0x9a/0x200 net/sched/act_api.c:1410 [<0000000088f3c5dd>] tc_ctl_action+0x14d/0x1bb net/sched/act_api.c:1465 [<000000006b39d986>] rtnetlink_rcv_msg+0x178/0x4b0 net/core/rtnetlink.c:5424 [<00000000fd6ecace>] netlink_rcv_skb+0x61/0x170 net/netlink/af_netlink.c:2477 [<0000000047493d02>] rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5442 [<00000000bdcf8286>] netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] [<00000000bdcf8286>] netlink_unicast+0x223/0x310 net/netlink/af_netlink.c:1328 [<00000000fc5b92d9>] netlink_sendmsg+0x2c0/0x570 net/netlink/af_netlink.c:1917 [<00000000da84d076>] sock_sendmsg_nosec net/socket.c:639 [inline] [<00000000da84d076>] sock_sendmsg+0x54/0x70 net/socket.c:659 [<0000000042fb2eee>] ____sys_sendmsg+0x2d0/0x300 net/socket.c:2330 [<000000008f23f67e>] ___sys_sendmsg+0x8a/0xd0 net/socket.c:2384 [<00000000d838e4f6>] __sys_sendmsg+0x80/0xf0 net/socket.c:2417 [<00000000289a9cb1>] __do_sys_sendmsg net/socket.c:2426 [inline] [<00000000289a9cb1>] __se_sys_sendmsg net/socket.c:2424 [inline] [<00000000289a9cb1>] __x64_sys_sendmsg+0x23/0x30 net/socket.c:2424 Fixes: 24ec483cec98 ("net: sched: Introduce act_ctinfo action") Signed-off-by: Eric Dumazet Reported-by: syzbot Cc: Kevin 'ldir' Darbyshire-Bryant Cc: Cong Wang Cc: Toke Høiland-Jørgensen Acked-by: Kevin 'ldir' Darbyshire-Bryant Signed-off-by: David S. Miller --- net/sched/act_ctinfo.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/net/sched/act_ctinfo.c b/net/sched/act_ctinfo.c index 40038c321b4a..19649623493b 100644 --- a/net/sched/act_ctinfo.c +++ b/net/sched/act_ctinfo.c @@ -360,6 +360,16 @@ static int tcf_ctinfo_search(struct net *net, struct tc_action **a, u32 index) return tcf_idr_search(tn, a, index); } +static void tcf_ctinfo_cleanup(struct tc_action *a) +{ + struct tcf_ctinfo *ci = to_ctinfo(a); + struct tcf_ctinfo_params *cp; + + cp = rcu_dereference_protected(ci->params, 1); + if (cp) + kfree_rcu(cp, rcu); +} + static struct tc_action_ops act_ctinfo_ops = { .kind = "ctinfo", .id = TCA_ID_CTINFO, @@ -367,6 +377,7 @@ static struct tc_action_ops act_ctinfo_ops = { .act = tcf_ctinfo_act, .dump = tcf_ctinfo_dump, .init = tcf_ctinfo_init, + .cleanup= tcf_ctinfo_cleanup, .walk = tcf_ctinfo_walker, .lookup = tcf_ctinfo_search, .size = sizeof(struct tcf_ctinfo),