linux/net
WANG Cong 98e3862ca2 kcm: fix 0-length case for kcm_sendmsg()
Dmitry reported a kernel warning:

 WARNING: CPU: 3 PID: 2936 at net/kcm/kcmsock.c:627
 kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627
 CPU: 3 PID: 2936 Comm: a.out Not tainted 4.10.0-rc6+ #209
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 Call Trace:
  __dump_stack lib/dump_stack.c:15 [inline]
  dump_stack+0x2ee/0x3ef lib/dump_stack.c:51
  panic+0x1fb/0x412 kernel/panic.c:179
  __warn+0x1c4/0x1e0 kernel/panic.c:539
  warn_slowpath_null+0x2c/0x40 kernel/panic.c:582
  kcm_write_msgs+0x12e3/0x1b90 net/kcm/kcmsock.c:627
  kcm_sendmsg+0x163a/0x2200 net/kcm/kcmsock.c:1029
  sock_sendmsg_nosec net/socket.c:635 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:645
  sock_write_iter+0x326/0x600 net/socket.c:848
  new_sync_write fs/read_write.c:499 [inline]
  __vfs_write+0x483/0x740 fs/read_write.c:512
  vfs_write+0x187/0x530 fs/read_write.c:560
  SYSC_write fs/read_write.c:607 [inline]
  SyS_write+0xfb/0x230 fs/read_write.c:599
  entry_SYSCALL_64_fastpath+0x1f/0xc2

when calling syscall(__NR_write, sock2, 0x208aaf27ul, 0x0ul) on a KCM
seqpacket socket. It appears that kcm_sendmsg() does not handle len==0
case correctly, which causes an empty skb is allocated and queued.
Fix this by skipping the skb allocation for len==0 case.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 16:38:48 -05:00
..
6lowpan 6lowpan: ndisc: no overreact if no short address is available 2016-09-19 20:19:34 +02:00
9p IB/core: add support to create a unsafe global rkey to ib_create_pd 2016-09-23 13:47:44 -04:00
802 Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
8021q Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
appletalk appletalk: use IS_ENABLED() instead of checking for built-in or module 2016-09-10 21:19:10 -07:00
atm net: atm: Fix warnings in net/atm/lec.c when !CONFIG_PROC_FS 2016-12-28 15:11:32 -05:00
ax25 ax25: Fix segfault after sock connection timeout 2017-01-16 14:39:58 -05:00
batman-adv batman-adv: Decrease hardif refcnt on fragmentation send error 2017-01-04 08:22:04 +01:00
bluetooth Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-12-16 10:24:44 -08:00
bridge bridge: netlink: call br_changelink() during br_dev_newlink() 2017-01-20 15:07:27 -05:00
caif Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-06 21:33:19 -05:00
can can: bcm: fix hrtimer/tasklet termination in bcm op removal 2017-01-30 11:05:04 +01:00
ceph libceph: make sure ceph_aes_crypt() IV is aligned 2017-01-18 17:58:45 +01:00
core udp: properly cope with csum errors 2017-02-07 11:19:00 -05:00
dcb net: dcb: set error code on failures 2016-12-03 23:54:25 -05:00
dccp tcp: don't annotate mark on control socket from tcp_v6_send_response() 2017-01-27 10:33:56 -05:00
decnet Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
dns_resolver
dsa net: dsa: Do not destroy invalid network devices 2017-02-08 14:50:51 -05:00
ethernet net: introduce device min_header_len 2017-02-08 13:56:37 -05:00
hsr Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-10-30 12:42:58 -04:00
ieee802154 Makefile: drop -D__CHECK_ENDIAN__ from cflags 2016-12-16 00:13:43 +02:00
ipv4 ping: fix a null pointer dereference 2017-02-08 13:58:21 -05:00
ipv6 sit: fix a double free on error path 2017-02-08 13:12:22 -05:00
ipx ktime: Get rid of the union 2016-12-25 17:21:22 +01:00
irda Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
iucv net/af_iucv: don't use paged skbs for TX on HiperSockets 2017-01-10 21:08:29 -05:00
kcm kcm: fix 0-length case for kcm_sendmsg() 2017-02-09 16:38:48 -05:00
key netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
l2tp l2tp: take remote address into account in l2tp_ip and l2tp_ip6 socket lookups 2017-01-01 22:07:20 -05:00
l3mdev net: ipv6: Remove l3mdev_get_saddr6 2016-09-10 23:12:53 -07:00
lapb Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
llc net: fix sleeping for sk_wait_event() 2016-11-14 13:17:21 -05:00
mac80211 mac80211: Fix adding of mesh vendor IEs 2017-02-06 07:55:44 +01:00
mac802154 ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
mpls net: Specify the owning module for lwtunnel ops 2017-01-24 16:21:36 -05:00
ncsi net/ncsi: Improve HNCDSC AEN handler 2016-10-20 11:23:08 -04:00
netfilter netfilter: nf_tables: bump set->ndeact on set flush 2017-01-24 21:46:59 +01:00
netlabel netlabel: add CALIPSO to the list of built-in protocols 2017-01-06 22:20:45 -05:00
netlink Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
netrom
nfc genetlink: mark families as __ro_after_init 2016-10-27 16:16:09 -04:00
openvswitch openvswitch: maintain correct checksum state in conntrack actions 2017-01-15 22:15:16 -05:00
packet packet: round up linear to header len 2017-02-08 13:56:37 -05:00
phonet netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
qrtr net: qrtr: Mark 'buf' as little endian 2017-01-10 20:45:04 -05:00
rds RDS: use rb_entry() 2016-12-20 14:22:49 -05:00
rfkill
rose Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
rxrpc rxrpc: abstract away knowledge of IDR internals 2016-12-14 16:04:10 -08:00
sched net/sched: matchall: Fix configuration race 2017-02-01 11:57:33 -05:00
sctp sctp: check af before verify address in sctp_addr_id2transport 2017-02-07 14:07:23 -05:00
strparser strparser: Propagate correct error code in strp_recv() 2016-10-12 01:51:49 -04:00
sunrpc svcrpc: fix oops in absence of krb5 module 2017-01-31 12:29:24 -05:00
switchdev Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-10-30 12:42:58 -04:00
tipc tipc: fix cleanup at module unload 2017-01-24 16:14:58 -05:00
unix af_unix: move unix_mknod() out of bindlock 2017-01-24 14:30:56 -05:00
vmw_vsock Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-17 20:17:04 -08:00
wimax genetlink: mark families as __ro_after_init 2016-10-27 16:16:09 -04:00
wireless nl80211: Fix mesh HT operation check 2017-02-06 07:59:07 +01:00
x25 Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
xfrm ktime: Cleanup ktime_set() usage 2016-12-25 17:21:22 +01:00
compat.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
Kconfig cgroup: move CONFIG_SOCK_CGROUP_DATA to init/Kconfig 2017-01-11 09:47:10 -05:00
Makefile
socket.c net: socket: Make unnecessarily global sockfs_setattr() static 2017-01-10 11:29:50 -05:00
sysctl_net.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2016-10-06 09:52:23 -07:00