linux_dsm_epyc7002/net/core
John Fastabend bd95e678e0 bpf: sockmap, fix use after free from sleep in psock backlog workqueue
Backlog work for psock (sk_psock_backlog) might sleep while waiting
for memory to free up when sending packets. However, while sleeping
the socket may be closed and removed from the map by the user space
side.

This breaks an assumption in sk_stream_wait_memory, which expects the
wait queue to be still there when it wakes up resulting in a
use-after-free shown below. To fix his mark sendmsg as MSG_DONTWAIT
to avoid the sleep altogether. We already set the flag for the
sendpage case but we missed the case were sendmsg is used.
Sockmap is currently the only user of skb_send_sock_locked() so only
the sockmap paths should be impacted.

==================================================================
BUG: KASAN: use-after-free in remove_wait_queue+0x31/0x70
Write of size 8 at addr ffff888069a0c4e8 by task kworker/0:2/110

CPU: 0 PID: 110 Comm: kworker/0:2 Not tainted 5.0.0-rc2-00335-g28f9d1a3d4fe-dirty #14
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
Workqueue: events sk_psock_backlog
Call Trace:
 print_address_description+0x6e/0x2b0
 ? remove_wait_queue+0x31/0x70
 kasan_report+0xfd/0x177
 ? remove_wait_queue+0x31/0x70
 ? remove_wait_queue+0x31/0x70
 remove_wait_queue+0x31/0x70
 sk_stream_wait_memory+0x4dd/0x5f0
 ? sk_stream_wait_close+0x1b0/0x1b0
 ? wait_woken+0xc0/0xc0
 ? tcp_current_mss+0xc5/0x110
 tcp_sendmsg_locked+0x634/0x15d0
 ? tcp_set_state+0x2e0/0x2e0
 ? __kasan_slab_free+0x1d1/0x230
 ? kmem_cache_free+0x70/0x140
 ? sk_psock_backlog+0x40c/0x4b0
 ? process_one_work+0x40b/0x660
 ? worker_thread+0x82/0x680
 ? kthread+0x1b9/0x1e0
 ? ret_from_fork+0x1f/0x30
 ? check_preempt_curr+0xaf/0x130
 ? iov_iter_kvec+0x5f/0x70
 ? kernel_sendmsg_locked+0xa0/0xe0
 skb_send_sock_locked+0x273/0x3c0
 ? skb_splice_bits+0x180/0x180
 ? start_thread+0xe0/0xe0
 ? update_min_vruntime.constprop.27+0x88/0xc0
 sk_psock_backlog+0xb3/0x4b0
 ? strscpy+0xbf/0x1e0
 process_one_work+0x40b/0x660
 worker_thread+0x82/0x680
 ? process_one_work+0x660/0x660
 kthread+0x1b9/0x1e0
 ? __kthread_create_on_node+0x250/0x250
 ret_from_fork+0x1f/0x30

Fixes: 20bf50de30 ("skbuff: Function to send an skbuf on a socket")
Reported-by: Jakub Sitnicki <jakub@cloudflare.com>
Tested-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-05-24 23:18:42 +02:00
..
bpf_sk_storage.c bpf: Use PTR_ERR_OR_ZERO in bpf_fd_sk_storage_update_elem() 2019-05-04 23:20:58 -07:00
datagram.c datagram: remove rendundant 'peeked' argument 2019-04-08 09:51:54 -07:00
datagram.h net/core: Allow the compiler to verify declaration and definition consistency 2019-03-27 13:49:44 -07:00
dev_addr_lists.c net: dev: Issue NETDEV_PRE_CHANGEADDR 2018-12-13 18:41:38 -08:00
dev_ioctl.c net/core: Document all dev_ioctl() arguments 2019-03-27 13:49:43 -07:00
dev.c net: avoid weird emergency message 2019-05-16 14:25:58 -07:00
devlink.c devlink: Change devlink health locking mechanism 2019-05-01 11:07:03 -04:00
drop_monitor.c genetlink: optionally validate strictly/dumps 2019-04-27 17:07:22 -04:00
dst_cache.c net: core: dst_cache_set_ip6: Rename 'addr' parameter to 'saddr' for consistency 2018-03-05 12:52:45 -05:00
dst.c net: dst: remove gc leftovers 2019-03-21 13:39:25 -07:00
ethtool.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-04-05 14:14:19 -07:00
failover.c failover: allow name change on IFF_UP slave interfaces 2019-04-10 22:12:26 -07:00
fib_notifier.c net: Fix fib notifer to return errno 2018-03-29 14:10:30 -04:00
fib_rules.c fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied 2019-05-08 09:32:10 -07:00
filter.c bpf: Check sk_fullsock() before returning from bpf_sk_lookup() 2019-05-21 16:33:30 +02:00
flow_dissector.c flow_dissector: disable preemption around BPF calls 2019-05-13 09:53:42 -07:00
flow_offload.c flow_offload: support CVLAN match 2019-05-16 12:02:42 -07:00
gen_estimator.c net: core: protect rate estimator statistics pointer with lock 2018-08-11 12:37:10 -07:00
gen_stats.c Revert: "net: sched: put back q.qlen into a single location" 2019-04-10 12:20:46 -07:00
gro_cells.c gro_cells: make sure device is up in gro_cells_receive() 2019-03-10 11:07:14 -07:00
hwbm.c net: hwbm: Fix unbalanced spinlock in error case 2016-05-25 12:35:09 -07:00
link_watch.c net: linkwatch: add check for netdevice being present to linkwatch_do_dev 2018-09-19 21:06:46 -07:00
lwt_bpf.c netlink: make validation more configurable for future strictness 2019-04-27 17:07:21 -04:00
lwtunnel.c netlink: make nla_nest_start() add NLA_F_NESTED flag 2019-04-27 17:03:44 -04:00
Makefile bpf: Introduce bpf sk local storage 2019-04-27 09:07:04 -07:00
neighbour.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-05-07 17:22:09 -07:00
net_namespace.c netlink: make validation more configurable for future strictness 2019-04-27 17:07:21 -04:00
net-procfs.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
net-sysfs.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2019-05-07 22:03:58 -07:00
net-sysfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
net-traces.c trace: events: add a few neigh tracepoints 2019-02-17 10:33:39 -08:00
netclassid_cgroup.c cgroup, netclassid: add a preemption point to write_classid 2018-10-23 12:58:17 -07:00
netevent.c netevent: remove automatic variable in register_netevent_notifier() 2015-05-31 00:03:21 -07:00
netpoll.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2019-05-07 22:03:58 -07:00
netprio_cgroup.c cgroup: net: remove left over MODULE_LICENSE tag 2019-04-22 21:50:54 -07:00
page_pool.c page_pool: use DMA_ATTR_SKIP_CPU_SYNC for DMA mappings 2019-02-13 22:00:16 -08:00
pktgen.c xfrm: remove output indirection from xfrm_mode 2019-04-08 09:14:28 +02:00
ptp_classifier.c net/core: work around section mismatch warning for ptp_classifier 2019-04-16 20:46:17 -07:00
request_sock.c ipv4: Namespaceify tcp_max_syn_backlog knob 2016-12-29 11:38:31 -05:00
rtnetlink.c rtnetlink: always put IFLA_LINK for links with a link-netnsid 2019-05-14 15:40:01 -07:00
scm.c socket: Add SO_TIMESTAMPING_NEW 2019-02-03 11:17:31 -08:00
secure_seq.c infiniband: i40iw, nes: don't use wall time for TCP sequence numbers 2018-07-11 12:10:19 -06:00
skbuff.c bpf: sockmap, fix use after free from sleep in psock backlog workqueue 2019-05-24 23:18:42 +02:00
skmsg.c bpf: sockmap fix msg->sg.size account on ingress skb 2019-05-14 01:31:43 +02:00
sock_diag.c net: sock_diag: Fix spectre v1 gadget in __sock_diag_cmd() 2018-08-14 10:01:24 -07:00
sock_map.c bpf: skmsg, fix psock create on existing kcm/tls port 2018-10-20 00:40:45 +02:00
sock_reuseport.c net/core: Document reuseport_add_sock() bind_inany argument 2019-03-27 13:49:43 -07:00
sock.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2019-04-28 08:42:41 -04:00
stream.c tcp: reduce POLLOUT events caused by TCP_NOTSENT_LOWAT 2018-12-04 21:21:18 -08:00
sysctl_net_core.c net: convert rps_needed and rfs_needed to new static branch api 2019-03-23 21:57:38 -04:00
timestamping.c net: skb_defer_rx_timestamp should check for phydev before setting up classify 2015-07-09 14:17:15 -07:00
tso.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
utils.c net: Remove some unneeded semicolon 2018-08-04 13:05:39 -07:00
xdp.c xdp: remove redundant variable 'headroom' 2018-09-01 01:35:53 +02:00