linux/net
Daniel Borkmann 8f2e5ae40e net: sctp: fix information leaks in ulpevent layer
While working on some other SCTP code, I noticed that some
structures shared with user space are leaking uninitialized
stack or heap buffer. In particular, struct sctp_sndrcvinfo
has a 2 bytes hole between .sinfo_flags and .sinfo_ppid that
remains unfilled by us in sctp_ulpevent_read_sndrcvinfo() when
putting this into cmsg. But also struct sctp_remote_error
contains a 2 bytes hole that we don't fill but place into a skb
through skb_copy_expand() via sctp_ulpevent_make_remote_error().

Both structures are defined by the IETF in RFC6458:

* Section 5.3.2. SCTP Header Information Structure:

  The sctp_sndrcvinfo structure is defined below:

  struct sctp_sndrcvinfo {
    uint16_t sinfo_stream;
    uint16_t sinfo_ssn;
    uint16_t sinfo_flags;
    <-- 2 bytes hole  -->
    uint32_t sinfo_ppid;
    uint32_t sinfo_context;
    uint32_t sinfo_timetolive;
    uint32_t sinfo_tsn;
    uint32_t sinfo_cumtsn;
    sctp_assoc_t sinfo_assoc_id;
  };

* 6.1.3. SCTP_REMOTE_ERROR:

  A remote peer may send an Operation Error message to its peer.
  This message indicates a variety of error conditions on an
  association. The entire ERROR chunk as it appears on the wire
  is included in an SCTP_REMOTE_ERROR event. Please refer to the
  SCTP specification [RFC4960] and any extensions for a list of
  possible error formats. An SCTP error notification has the
  following format:

  struct sctp_remote_error {
    uint16_t sre_type;
    uint16_t sre_flags;
    uint32_t sre_length;
    uint16_t sre_error;
    <-- 2 bytes hole  -->
    sctp_assoc_t sre_assoc_id;
    uint8_t  sre_data[];
  };

Fix this by setting both to 0 before filling them out. We also
have other structures shared between user and kernel space in
SCTP that contains holes (e.g. struct sctp_paddrthlds), but we
copy that buffer over from user space first and thus don't need
to care about it in that cases.

While at it, we can also remove lengthy comments copied from
the draft, instead, we update the comment with the correct RFC
number where one can look it up.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 14:18:56 -07:00
..
9p A bunch of updates and cleanup within the transport layer, 2014-04-11 14:14:57 -07:00
802
8021q vlan: free percpu stats in device destructor 2014-07-02 17:02:05 -07:00
appletalk appletalk: Fix socket referencing in skb 2014-07-08 19:39:43 -07:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-06-12 14:27:40 -07:00
ax25 net: Fix use after free by removing length arg from sk_data_ready callbacks. 2014-04-11 16:15:36 -04:00
batman-adv net: add __pskb_copy_fclone and pskb_copy_for_clone 2014-06-11 15:38:02 -07:00
bluetooth Bluetooth: Fix for ACL disconnect when pairing fails 2014-06-20 13:53:54 +02:00
bridge bridge: fix compile error when compiling without IPv6 support 2014-06-12 11:00:24 -07:00
caif net: Fix use after free by removing length arg from sk_data_ready callbacks. 2014-04-11 16:15:36 -04:00
can can: add hash based access to single EFF frame filters 2014-05-19 09:38:24 +02:00
ceph Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client 2014-06-12 23:06:23 -07:00
core net: Fix NETDEV_CHANGE notifier usage causing spurious arp flush 2014-07-07 21:20:01 -07:00
dcb net: Use netlink_ns_capable to verify the permisions of netlink messages 2014-04-24 13:44:54 -04:00
dccp net: Eliminate no_check from protosw 2014-05-23 16:28:53 -04:00
decnet net: Split sk_no_check into sk_no_check_{rx,tx} 2014-05-23 16:28:53 -04:00
dns_resolver Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-06-11 16:02:55 -07:00
dsa Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-05-24 00:32:30 -04:00
ethernet
hsr hsr: replace del_timer by del_timer_sync 2014-03-27 15:28:06 -04:00
ieee802154 6lowpan_rtnl: fix off by one while fragmentation 2014-06-02 10:39:42 -07:00
ipv4 GRE: enable offloads for GRE 2014-07-11 13:53:39 -07:00
ipv6 ipv6: Fix MLD Query message check 2014-06-27 00:21:50 -07:00
ipx net: Split sk_no_check into sk_no_check_{rx,tx} 2014-05-23 16:28:53 -04:00
irda
iucv af_iucv: correct cleanup if listen backlog is full 2014-05-30 17:35:23 -07:00
key af_key: Replace comma with semicolon 2014-05-30 17:48:58 -07:00
l2tp l2tp: call udp{6}_set_csum 2014-06-04 22:46:38 -07:00
lapb
llc
mac80211 mac80211: WEP extra head/tail room in ieee80211_send_auth 2014-06-23 10:45:14 +02:00
mac802154 mac802154: don't deliver packets to devices that are down 2014-06-11 12:10:19 -07:00
mpls gre: Call gso_make_checksum 2014-06-04 22:46:38 -07:00
netfilter netfilter: nf_nat: fix oops on netns removal 2014-06-16 13:58:54 +02:00
netlabel
netlink netlink: Fix handling of error from netlink_dump(). 2014-07-09 14:33:47 -07:00
netrom net: Fix use after free by removing length arg from sk_data_ready callbacks. 2014-04-11 16:15:36 -04:00
nfc net: add __pskb_copy_fclone and pskb_copy_for_clone 2014-06-11 15:38:02 -07:00
openvswitch openvswitch: Use exact lookup for flow_get and flow_del. 2014-06-30 20:47:15 -07:00
packet net: Use netlink_ns_capable to verify the permisions of netlink messages 2014-04-24 13:44:54 -04:00
phonet net: Use netlink_ns_capable to verify the permisions of netlink messages 2014-04-24 13:44:54 -04:00
rds Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-06-12 14:27:40 -07:00
rfkill Merge git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next 2014-05-22 13:58:36 -04:00
rose net: Fix use after free by removing length arg from sk_data_ready callbacks. 2014-04-11 16:15:36 -04:00
rxrpc af_rxrpc: Fix XDR length check in rxrpc key demarshalling. 2014-05-16 15:24:47 -04:00
sched net_sched: drr: warn when qdisc is not work conserving 2014-06-11 15:50:59 -07:00
sctp net: sctp: fix information leaks in ulpevent layer 2014-07-14 14:18:56 -07:00
sunrpc NFSv4: test SECINFO RPC_AUTH_GSS pseudoflavors for support 2014-06-24 18:46:58 -04:00
tipc tipc: clear 'next'-pointer of message fragments before reassembly 2014-07-11 15:02:10 -07:00
unix Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-06-12 14:27:40 -07:00
vmw_vsock vsock: Make transport the proto owner 2014-05-05 13:13:50 -04:00
wimax
wireless nl80211: move set_qos_map command into split state 2014-06-24 16:13:10 +02:00
x25 net: Fix use after free by removing length arg from sk_data_ready callbacks. 2014-04-11 16:15:36 -04:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-06-03 23:32:12 -07:00
compat.c net/compat: convert to COMPAT_SYSCALL_DEFINE with changing parameter types 2014-03-06 16:30:45 +01:00
Kconfig Merge branch 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2014-04-03 13:05:42 -07:00
Makefile
nonet.c
socket.c net: use SYSCALL_DEFINEx for sys_recv 2014-04-16 15:15:05 -04:00
sysctl_net.c