linux/net
Cong Wang 6d8c50dcb0 socket: close race condition between sock_close() and sockfs_setattr()
fchownat() doesn't even hold refcnt of fd until it figures out
fd is really needed (otherwise is ignored) and releases it after
it resolves the path. This means sock_close() could race with
sockfs_setattr(), which leads to a NULL pointer dereference
since typically we set sock->sk to NULL in ->release().

As pointed out by Al, this is unique to sockfs. So we can fix this
in socket layer by acquiring inode_lock in sock_close() and
checking against NULL in sockfs_setattr().

sock_release() is called in many places, only the sock_close()
path matters here. And fortunately, this should not affect normal
sock_close() as it is only called when the last fd refcnt is gone.
It only affects sock_close() with a parallel sockfs_setattr() in
progress, which is not common.

Fixes: 86741ec254 ("net: core: Add a UID field to struct sock.")
Reported-by: shankarapailoor <shankarapailoor@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-06-10 12:25:53 -07:00
..
6lowpan
9p Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
802
8021q Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
appletalk Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
atm Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
ax25 Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-26 19:46:15 -04:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
bpf bpf: making bpf_prog_test run aware of possible data_end ptr change 2018-04-18 23:34:16 +02:00
bpfilter bpfilter: fix race in pipe access 2018-06-07 20:07:28 -04:00
bridge net: bridge: Fix locking in br_fdb_find_port() 2018-06-08 19:58:31 -04:00
caif net/caif: convert to ->poll_mask 2018-05-26 09:16:44 +02:00
can Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
ceph - Introduce arithmetic overflow test helper functions (Rasmus) 2018-06-06 17:27:14 -07:00
core Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
dcb net/dcb: Add dcbnl buffer attribute 2018-05-24 14:22:59 -07:00
dccp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
dns_resolver KEYS: DNS: limit the length of option strings 2018-04-17 15:17:41 -04:00
dsa dsa: port: Ignore bridge VLAN events 2018-05-31 14:13:43 -04:00
ethernet net: core: rework basic flow dissection helper 2018-05-08 00:02:36 -04:00
hsr
ieee802154 Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
ife net: sched: ife: check on metadata length 2018-04-22 21:12:00 -04:00
ipv4 udp: fix rx queue len reported by diag and proc interface 2018-06-08 19:55:15 -04:00
ipv6 udp: fix rx queue len reported by diag and proc interface 2018-06-08 19:55:15 -04:00
iucv net/iucv: convert to ->poll_mask 2018-05-26 09:16:44 +02:00
kcm Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
key Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
l2tp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
l3mdev
lapb
llc Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
mac80211 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-05-26 19:46:15 -04:00
mac802154 net/mac802154: disambiguate mac80215 vs mac802154 trace events 2018-03-28 22:55:18 +02:00
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: Avoid GFP_KERNEL in response handler 2018-06-03 10:42:07 -04:00
netfilter netfilter: nf_tables: add NFT_LOGLEVEL_* enumeration and use it 2018-06-07 16:14:00 -04:00
netlabel audit: use inline function to get audit context 2018-05-14 17:24:18 -04:00
netlink Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
netrom Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
nsh nsh: fix infinite loop 2018-05-04 12:54:38 -04:00
openvswitch openvswitch: Support conntrack zone limit 2018-05-25 16:45:19 -04:00
packet net: in virtio_net_hdr only add VLAN_HLEN to csum_start if payload holds vlan 2018-06-07 16:15:38 -04:00
phonet Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
psample
qrtr Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
rds Merge candidates for 4.17-rc 2018-06-02 09:55:44 -07:00
rfkill rfkill: Create rfkill-none LED trigger 2018-05-23 11:26:45 +02:00
rose Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
rxrpc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
sched net/sched: act_simple: fix parsing of TCA_DEF_DATA 2018-06-08 18:49:19 -04:00
sctp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
smc net/smc: fix error return code in smc_setsockopt() 2018-06-03 10:38:28 -04:00
strparser strparser: Add __strp_unpause and use it in ktls. 2018-06-06 14:07:53 -04:00
sunrpc Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 10:14:28 -07:00
switchdev
tipc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
tls strparser: Add __strp_unpause and use it in ktls. 2018-06-06 14:07:53 -04:00
unix Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
vmw_vsock net/vmw_vsock: convert to ->poll_mask 2018-05-26 09:16:44 +02:00
wimax
wireless Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
x25 Merge branch 'work.aio-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-06-04 13:57:43 -07:00
xdp bpf, xdp: fix crash in xdp_umem_unaccount_pages 2018-06-07 15:32:28 -07:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-06-06 18:39:49 -07:00
compat.c net: support compat 64-bit time in {s,g}etsockopt 2018-04-27 19:46:06 -04:00
Kconfig net: Introduce generic failover module 2018-05-28 22:59:54 -04:00
Makefile bpfilter: switch to CC from HOSTCC 2018-06-05 10:21:18 -04:00
socket.c socket: close race condition between sock_close() and sockfs_setattr() 2018-06-10 12:25:53 -07:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00