linux/net
Kees Cook 79a8a642bf net: Whitelist the skbuff_head_cache "cb" field
Most callers of put_cmsg() use a "sizeof(foo)" for the length argument.
Within put_cmsg(), a copy_to_user() call is made with a dynamic size, as a
result of the cmsg header calculations. This means that hardened usercopy
will examine the copy, even though it was technically a fixed size and
should be implicitly whitelisted. All the put_cmsg() calls being built
from values in skbuff_head_cache are coming out of the protocol-defined
"cb" field, so whitelist this field entirely instead of creating per-use
bounce buffers, for which there are concerns about performance.

Original report was:

Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLAB object 'skbuff_head_cache' (offset 64, size 16)!
WARNING: CPU: 0 PID: 3663 at mm/usercopy.c:81 usercopy_warn+0xdb/0x100 mm/usercopy.c:76
...
 __check_heap_object+0x89/0xc0 mm/slab.c:4426
 check_heap_object mm/usercopy.c:236 [inline]
 __check_object_size+0x272/0x530 mm/usercopy.c:259
 check_object_size include/linux/thread_info.h:112 [inline]
 check_copy_size include/linux/thread_info.h:143 [inline]
 copy_to_user include/linux/uaccess.h:154 [inline]
 put_cmsg+0x233/0x3f0 net/core/scm.c:242
 sock_recv_errqueue+0x200/0x3e0 net/core/sock.c:2913
 packet_recvmsg+0xb2e/0x17a0 net/packet/af_packet.c:3296
 sock_recvmsg_nosec net/socket.c:803 [inline]
 sock_recvmsg+0xc9/0x110 net/socket.c:810
 ___sys_recvmsg+0x2a4/0x640 net/socket.c:2179
 __sys_recvmmsg+0x2a9/0xaf0 net/socket.c:2287
 SYSC_recvmmsg net/socket.c:2368 [inline]
 SyS_recvmmsg+0xc4/0x160 net/socket.c:2352
 entry_SYSCALL_64_fastpath+0x29/0xa0

Reported-by: syzbot+e2d6cfb305e9f3911dea@syzkaller.appspotmail.com
Fixes: 6d07d1cd30 ("usercopy: Restrict non-usercopy caches to size 0")
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-08 15:15:48 -05:00
..
6lowpan License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
9p Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-30 17:58:07 -08:00
802 treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
8021q net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
appletalk net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
ax25 net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
bpf bpf: fix null pointer deref in bpf_prog_test_run_xdp 2018-02-01 07:43:56 -08:00
bridge net: bridge: Fix uninitialized error in br_fdb_sync_static() 2018-02-01 09:47:37 -05:00
caif Currently, hardened usercopy performs dynamic bounds checking on slab 2018-02-03 16:25:42 -08:00
can can: migrate documentation to restructured text 2018-01-26 10:46:44 +01:00
ceph We have a set of file locking improvements from Zheng, rbd rw/ro 2017-11-21 05:38:32 -10:00
core net: Whitelist the skbuff_head_cache "cb" field 2018-02-08 15:15:48 -05:00
dcb
dccp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
decnet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
dns_resolver KEYS: Fix race between updating and finding a negative key 2017-10-18 09:12:40 +01:00
dsa net: dsa: Support internal phy on 'cpu' port 2018-01-23 19:22:38 -05:00
ethernet
hsr net: hsr: Convert timers to use timer_setup() 2017-10-25 13:00:27 +09:00
ieee802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
ife MAINTAINERS: Update Yotam's E-mail 2017-11-01 12:19:03 +09:00
ipv4 tcp: tracepoint: only call trace_tcp_send_reset with full socket 2018-02-07 22:00:42 -05:00
ipv6 tcp: tracepoint: only call trace_tcp_send_reset with full socket 2018-02-07 22:00:42 -05:00
iucv net: annotate ->poll() instances 2017-11-27 16:20:04 -05:00
kcm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-01-24 23:44:15 -05:00
key af_key: Fix memory leak in key_notify_policy. 2018-01-10 09:45:11 +01:00
l2tp l2tp: remove switch block in l2tp_nl_cmd_session_create() 2018-01-19 15:10:23 -05:00
l3mdev
lapb treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
llc net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
mac80211 debugfs_sta: Remove unneeded semicolons 2018-01-22 14:03:28 +01:00
mac802154 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
mpls net: use rtnl_register_module where needed 2017-12-04 11:32:39 -05:00
ncsi net/ncsi: Don't take any action on HNCDSC AEN 2017-12-18 14:50:11 -05:00
netfilter netfilter: nf_flow_offload: fix use-after-free and a resource leak 2018-02-07 11:55:52 +01:00
netlabel net/netlabel: Add list_next_rcu() in rcu_dereference(). 2017-11-18 10:32:41 +09:00
netlink netlink: ensure to loop over all netns in genlmsg_multicast_allns() 2018-02-08 14:03:18 -05:00
netrom net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
nfc net: annotate ->poll() instances 2017-11-27 16:20:04 -05:00
nsh openvswitch: enable NSH support 2017-11-08 16:12:33 +09:00
openvswitch openvswitch: Remove padding from packet before L3+ conntrack processing 2018-02-01 09:46:22 -05:00
packet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
phonet Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
psample MAINTAINERS: Update Yotam's E-mail 2017-11-01 12:19:03 +09:00
qrtr net: use rtnl_register_module where needed 2017-12-04 11:32:39 -05:00
rds RDS: IB: Fix null pointer issue 2018-02-06 11:44:32 -05:00
rfkill net: annotate ->poll() instances 2017-11-27 16:20:04 -05:00
rose net: delete /proc THIS_MODULE references 2018-01-16 15:01:33 -05:00
rxrpc rxrpc: Don't put crypto buffers on the stack 2018-02-08 13:48:29 -05:00
sched sch_netem: Bug fixing in calculating Netem interval 2018-02-07 21:59:12 -05:00
sctp sctp: fix dst refcnt leak in sctp_v4_get_dst 2018-02-05 21:21:51 -05:00
smc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
strparser strparser: Call sock_owned_by_user_nocheck 2017-12-28 14:28:22 -05:00
sunrpc NFS client updates for Linux 4.16 2018-01-30 19:03:48 -08:00
switchdev net: bridge: Add/del switchdev object on host join/leave 2017-11-10 13:41:40 +09:00
tipc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
tls tls: Add support for encryption using async offload accelerator 2018-01-31 10:26:30 -05:00
unix Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
vmw_vsock Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-01-30 17:58:07 -08:00
wimax License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
wireless Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-02-04 11:45:55 -08:00
x25 treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-01-26 10:22:53 -05:00
compat.c
Kconfig Staging/IIO patches for 4.16-rc1 2018-02-01 09:51:57 -08:00
Makefile ipx: move Novell IPX protocol support into staging 2017-11-28 13:55:00 +01:00
socket.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-01-31 14:31:10 -08:00
sysctl_net.c