linux/net
Yue Haibing ff960f9d3e netns: Make get_net_ns() handle zero refcount net
Syzkaller hit a warning:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 3 PID: 7890 at lib/refcount.c:25 refcount_warn_saturate+0xdf/0x1d0
Modules linked in:
CPU: 3 PID: 7890 Comm: tun Not tainted 6.10.0-rc3-00100-gcaa4f9578aba-dirty #310
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0xdf/0x1d0
Code: 41 49 04 31 ff 89 de e8 9f 1e cd fe 84 db 75 9c e8 76 26 cd fe c6 05 b6 41 49 04 01 90 48 c7 c7 b8 8e 25 86 e8 d2 05 b5 fe 90 <0f> 0b 90 90 e9 79 ff ff ff e8 53 26 cd fe 0f b6 1
RSP: 0018:ffff8881067b7da0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c72ac
RDX: ffff8881026a2140 RSI: ffffffff811c72b5 RDI: 0000000000000001
RBP: ffff8881067b7db0 R08: 0000000000000000 R09: 205b5d3730353139
R10: 0000000000000000 R11: 205d303938375420 R12: ffff8881086500c4
R13: ffff8881086500c4 R14: ffff8881086500b0 R15: ffff888108650040
FS:  00007f5b2961a4c0(0000) GS:ffff88823bd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d7ed36fd18 CR3: 00000001482f6000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 ? show_regs+0xa3/0xc0
 ? __warn+0xa5/0x1c0
 ? refcount_warn_saturate+0xdf/0x1d0
 ? report_bug+0x1fc/0x2d0
 ? refcount_warn_saturate+0xdf/0x1d0
 ? handle_bug+0xa1/0x110
 ? exc_invalid_op+0x3c/0xb0
 ? asm_exc_invalid_op+0x1f/0x30
 ? __warn_printk+0xcc/0x140
 ? __warn_printk+0xd5/0x140
 ? refcount_warn_saturate+0xdf/0x1d0
 get_net_ns+0xa4/0xc0
 ? __pfx_get_net_ns+0x10/0x10
 open_related_ns+0x5a/0x130
 __tun_chr_ioctl+0x1616/0x2370
 ? __sanitizer_cov_trace_switch+0x58/0xa0
 ? __sanitizer_cov_trace_const_cmp2+0x1c/0x30
 ? __pfx_tun_chr_ioctl+0x10/0x10
 tun_chr_ioctl+0x2f/0x40
 __x64_sys_ioctl+0x11b/0x160
 x64_sys_call+0x1211/0x20d0
 do_syscall_64+0x9e/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5b28f165d7
Code: b3 66 90 48 8b 05 b1 48 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 8
RSP: 002b:00007ffc2b59c5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5b28f165d7
RDX: 0000000000000000 RSI: 00000000000054e3 RDI: 0000000000000003
RBP: 00007ffc2b59c650 R08: 00007f5b291ed8c0 R09: 00007f5b2961a4c0
R10: 0000000029690010 R11: 0000000000000246 R12: 0000000000400730
R13: 00007ffc2b59cf40 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
Kernel panic - not syncing: kernel: panic_on_warn set ...

This is trigger as below:
          ns0                                    ns1
tun_set_iff() //dev is tun0
   tun->dev = dev
//ip link set tun0 netns ns1
                                       put_net() //ref is 0
__tun_chr_ioctl() //TUNGETDEVNETNS
   net = dev_net(tun->dev);
   open_related_ns(&net->ns, get_net_ns); //ns1
     get_net_ns()
        get_net() //addition on 0

Use maybe_get_net() in get_net_ns in case net's ref is zero to fix this

Fixes: 0c3e0e3bb6 ("tun: Add ioctl() TUNGETDEVNETNS cmd to allow obtaining real net ns of tun device")
Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20240614131302.2698509-1-yuehaibing@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-18 10:59:52 +02:00
..
6lowpan
9p Two fixes headed to stable trees: 2024-05-29 09:25:15 -07:00
802
8021q net: annotate writes on dev->mtu from ndo_change_mtu() 2024-05-07 16:19:14 -07:00
appletalk Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-05-09 10:01:01 -07:00
atm net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
ax25 ax25: Replace kfree() in ax25_dev_free() with ax25_dev_put() 2024-06-01 15:49:42 -07:00
batman-adv tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
bluetooth Bluetooth: fix connection setup in l2cap_connect 2024-06-10 09:48:30 -04:00
bpf bpf: Set run context for rawtp test_run callback 2024-06-05 09:41:33 +02:00
bridge net: bridge: mst: fix suspicious rcu usage in br_mst_set_state 2024-06-12 18:24:24 -07:00
caif caif: Use UTILITY_NAME_LENGTH instead of hard-coding 16 2024-04-02 18:20:00 -07:00
can
ceph
core netns: Make get_net_ns() handle zero refcount net 2024-06-18 10:59:52 +02:00
dcb
dccp net: dccp: Fix ccid2_rtt_estimator() kernel-doc 2024-05-07 16:15:08 -07:00
devlink devlink: extend devlink_param *set pointer 2024-04-22 13:05:19 -07:00
dns_resolver
dsa tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
ethernet netkit: Fix pkt_type override upon netkit pass verdict 2024-05-25 10:48:57 -07:00
ethtool net: ethtool: fix the error condition in ethtool_get_phy_stats_ethtool() 2024-06-06 13:34:33 +02:00
handshake net/handshake: remove redundant assignment to variable ret 2024-04-16 17:14:55 -07:00
hsr Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-05-09 10:01:01 -07:00
ieee802154 tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
ife
ipv4 tcp: clear tp->retrans_stamp in tcp_rcv_fastopen_synack() 2024-06-17 17:50:39 -07:00
ipv6 xfrm6: check ip6_dst_idev() return value in xfrm6_get_saddr() 2024-06-17 18:04:46 -07:00
iucv more s390 updates for 6.10 merge window 2024-05-21 12:09:36 -07:00
kcm
key
l2tp l2tp: fix ICMP error handling for UDP-encap sockets 2024-05-17 12:15:22 -07:00
l3mdev
lapb
llc net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
mac80211 wifi: mac80211: fix monitor channel with chanctx emulation 2024-06-14 09:14:08 +02:00
mac802154
mctp
mpls net: Remove the now superfluous sentinel elements from ctl_table array 2024-05-03 13:29:41 +01:00
mptcp mptcp: pm: update add_addr counters after connect 2024-06-10 19:49:10 -07:00
ncsi net/ncsi: Fix the multi thread manner of NCSI driver 2024-06-01 16:21:44 -07:00
netfilter netfilter: ipset: Fix race between namespace cleanup and gc in the list:set type 2024-06-11 18:46:04 +02:00
netlabel netlabel: fix RCU annotation for IPv4 options on socket creation 2024-05-13 14:58:12 -07:00
netlink netlink: support all extack types in dumps 2024-04-23 10:09:49 -07:00
netrom netrom: Fix a memory leak in nr_heartbeat_expiry() 2024-06-17 13:06:23 +01:00
nfc Quite smaller than usual. Notably it includes the fix for the unix 2024-05-23 12:49:37 -07:00
nsh nsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment(). 2024-04-26 12:20:01 +02:00
openvswitch Quite smaller than usual. Notably it includes the fix for the unix 2024-05-23 12:49:37 -07:00
packet af_packet: do not call packet_read_pending() from tpacket_destruct_skb() 2024-05-16 19:38:05 -07:00
phonet net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
psample ip_tunnel: convert __be16 tunnel flags to bitmaps 2024-04-01 10:49:28 +01:00
qrtr net: qrtr: ns: Fix module refcnt 2024-05-16 09:47:45 +01:00
rds net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
rfkill net: rfkill: gpio: Convert to platform remove callback returning void 2024-03-25 15:40:22 +01:00
rose net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
rxrpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2024-05-09 10:01:01 -07:00
sched net/sched: initialize noop_qdisc owner 2024-06-10 19:36:49 -07:00
sctp net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
smc net/smc: avoid overwriting when adjusting sock bufsizes 2024-06-05 09:42:57 +01:00
strparser
sunrpc NFS client bugfixes for Linux 6.10 2024-06-13 11:07:32 -07:00
switchdev net: bridge: switchdev: Improve error message for port_obj_add/del functions 2024-05-08 12:19:12 +01:00
tipc tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
tls tls: fix missing memory barrier in tls_init 2024-05-23 12:03:26 +02:00
unix af_unix: Read with MSG_PEEK loops if the first unread byte is OOB 2024-06-13 08:03:55 -07:00
vmw_vsock virtio: features, fixes, cleanups 2024-05-23 12:04:36 -07:00
wireless wifi: cfg80211: wext: add extra SIOCSIWSCAN data check 2024-06-12 10:07:56 +02:00
x25 net: change proto and proto_ops accept type 2024-05-13 18:19:09 -06:00
xdp Revert "xsk: Support redirect to any socket bound to the same umem" 2024-06-05 09:42:30 +02:00
xfrm net: fix __dst_negative_advice() race 2024-05-29 17:34:49 -07:00
compat.c
devres.c
Kconfig net: add IEEE 802.1q specific helpers 2024-05-08 10:35:09 +01:00
Kconfig.debug
Makefile
socket.c net: have do_accept() take a struct proto_accept_arg argument 2024-05-13 18:19:19 -06:00
sysctl_net.c sysctl: treewide: constify argument ctl_table_root::permissions(table) 2024-04-24 09:43:54 +02:00