[ Upstream commit 85fbaa7503 ]
Commit bceaa90240 ("inet: prevent leakage
of uninitialized memory to user in recv syscalls") conditionally updated
addr_len if the msg_name is written to. The recv_error and rxpmtu
functions relied on the recvmsg functions to set up addr_len before.
As this does not happen any more we have to pass addr_len to those
functions as well and set it to the size of the corresponding sockaddr
length.
This broke traceroute and such.
Fixes: bceaa90240 ("inet: prevent leakage of uninitialized memory to user in recv syscalls")
Reported-by: Brad Spengler <spender@grsecurity.net>
Reported-by: Tom Labanowski
Cc: mpb <mpb.mail@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f3d3342602 ]
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.
This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.
Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.
Also document these changes in include/linux/net.h as suggested by David
Miller.
Changes since RFC:
Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.
With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".
This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.
Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.
Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit bceaa90240 ]
Only update *addr_len when we actually fill in sockaddr, otherwise we
can return uninitialized memory from the stack to the caller in the
recvfrom, recvmmsg and recvmsg syscalls. Drop the the (addr_len == NULL)
checks because we only get called with a valid addr_len pointer either
from sock_common_recvmsg or inet_recvmsg.
If a blocking read waits on a socket which is concurrently shut down we
now return zero and set msg_msgnamelen to 0.
Reported-by: mpb <mpb.mail@gmail.com>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8d8a51e26a ]
net/l2tp/l2tp_core.c: In function ‘l2tp_verify_udp_checksum’:
net/l2tp/l2tp_core.c:499:22: warning: unused variable ‘tunnel’ [-Wunused-variable]
Create a helper "l2tp_tunnel()" to facilitate this, and as a side
effect get rid of a bunch of unnecessary void pointer casts.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
PPPoL2TP sockets should comply with the standard send*() return values
(i.e. return number of bytes sent instead of 0 upon success).
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Copy user data after PPP framing header. This prevents erasure of the
added PPP header and avoids leaking two bytes of uninitialised memory
at the end of skb's data buffer.
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/nfc/microread/mei.c
net/netfilter/nfnetlink_queue_core.c
Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which
some cleanups are going to go on-top.
Signed-off-by: David S. Miller <davem@davemloft.net>
The L2TP code for IPv6 fails to initialize the l2tp_conn_id member of
struct sockaddr_l2tpip6 and therefore leaks four bytes kernel stack
in l2tp_ip6_recvmsg() in case msg_name is set.
Initialize l2tp_conn_id with 0 to avoid the info leak.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a cut and paste typo. We call ->ref() a second time instead
of ->deref().
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If we postpone unhashing of l2tp sessions until the structure is freed, we
risk:
1. further packets arriving and getting queued while the pseudowire is being
closed down
2. the recv path hitting "scheduling while atomic" errors in the case that
recv drops the last reference to a session and calls l2tp_session_free
while in atomic context
As such, l2tp sessions should be unhashed from l2tp_core data structures early
in the teardown process prior to calling pseudowire close. For pseudowires
like l2tp_ppp which have multiple shutdown codepaths, provide an unhash hook.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp's u64_stats writers were incorrectly synchronised, making it possible to
deadlock a 64bit machine running a 32bit kernel simply by sending the l2tp
code netlink commands while passing data through l2tp sessions.
Previous discussion on netdev determined that alternative solutions such as
spinlock writer synchronisation or per-cpu data would bring unjustified
overhead, given that most users interested in high volume traffic will likely
be running 64bit kernels on 64bit hardware.
As such, this patch replaces l2tp's use of u64_stats with atomic_long_t,
thereby avoiding the deadlock.
Ref:
http://marc.info/?l=linux-netdev&m=134029167910731&w=2http://marc.info/?l=linux-netdev&m=134079868111131&w=2
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If userspace deletes a ppp pseudowire using the netlink API, either by
directly deleting the session or by deleting the tunnel that contains the
session, we need to tear down the corresponding pppox channel.
Rather than trying to manage two pppox unbind codepaths, switch the netlink
and l2tp_core session_close handlers to close via. the l2tp_ppp socket
.release handler.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add calls to l2tp_session_queue_purge as a part of l2tp_tunnel_closeall
and l2tp_session_delete. Pseudowire implementations which are deleted only
via. l2tp_core l2tp_session_delete calls can dispense with their own code for
flushing the reorder queue.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If an l2tp session is deleted, it is necessary to delete skbs in-flight
on the session's reorder queue before taking it down.
Rather than having each pseudowire implementation reaching into the
l2tp_session struct to handle this itself, provide a function in l2tp_core to
purge the session queue.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is valid for an existing struct sock object to have a NULL sk_socket
pointer, so don't BUG_ON in l2tp_tunnel_del_work if that should occur.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When looking up the tunnel socket in struct l2tp_tunnel, hold a reference
whether the socket was created by the kernel or by userspace.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a user deletes a tunnel using netlink, all the sessions in the tunnel
should also be deleted. Since running sessions will pin the tunnel socket
with the references they hold, have the l2tp_tunnel_delete close all sessions
in a tunnel before finally closing the tunnel socket.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp_core hooks UDP's .destroy handler to gain advance warning of a tunnel
socket being closed from userspace. We need to do the same thing for
IP-encapsulation sockets.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
l2tp_core internally uses l2tp_tunnel_closeall to close all sessions in a
tunnel when a UDP-encapsulation socket is destroyed. We need to do something
similar for IP-encapsulation sockets.
Export l2tp_tunnel_closeall as a GPL symbol to enable l2tp_ip and l2tp_ip6 to
call it from their .destroy handlers.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
L2TP sessions hold a reference to the tunnel socket to prevent it going away
while sessions are still active. However, since tunnel destruction is handled
by the sock sk_destruct callback there is a catch-22: a tunnel with sessions
cannot be deleted since each session holds a reference to the tunnel socket.
If userspace closes a managed tunnel socket, or dies, the tunnel will persist
and it will be neccessary to individually delete the sessions using netlink
commands. This is ugly.
To prevent this occuring, this patch leverages the udp encapsulation socket
destroy callback to gain early notification when the tunnel socket is closed.
This allows us to safely close the sessions running in the tunnel, dropping
the tunnel socket references in the process. The tunnel socket is then
destroyed as normal, and the tunnel resources deallocated in sk_destruct.
While we're at it, ensure that l2tp_tunnel_closeall correctly drops session
references to allow the sessions to be deleted rather than leaking.
Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
"A moderately sized pile of fixes, some specifically for merge window
introduced regressions although others are for longer standing items
and have been queued up for -stable.
I'm kind of tired of all the RDS protocol bugs over the years, to be
honest, it's way out of proportion to the number of people who
actually use it.
1) Fix missing range initialization in netfilter IPSET, from Jozsef
Kadlecsik.
2) ieee80211_local->tim_lock needs to use BH disabling, from Johannes
Berg.
3) Fix DMA syncing in SFC driver, from Ben Hutchings.
4) Fix regression in BOND device MAC address setting, from Jiri
Pirko.
5) Missing usb_free_urb in ISDN Hisax driver, from Marina Makienko.
6) Fix UDP checksumming in bnx2x driver for 57710 and 57711 chips,
fix from Dmitry Kravkov.
7) Missing cfgspace_lock initialization in BCMA driver.
8) Validate parameter size for SCTP assoc stats getsockopt(), from
Guenter Roeck.
9) Fix SCTP association hangs, from Lee A Roberts.
10) Fix jumbo frame handling in r8169, from Francois Romieu.
11) Fix phy_device memory leak, from Petr Malat.
12) Omit trailing FCS from frames received in BGMAC driver, from Hauke
Mehrtens.
13) Missing socket refcount release in L2TP, from Guillaume Nault.
14) sctp_endpoint_init should respect passed in gfp_t, rather than use
GFP_KERNEL unconditionally. From Dan Carpenter.
15) Add AISX AX88179 USB driver, from Freddy Xin.
16) Remove MAINTAINERS entries for drivers deleted during the merge
window, from Cesar Eduardo Barros.
17) RDS protocol can try to allocate huge amounts of memory, check
that the user's request length makes sense, from Cong Wang.
18) SCTP should use the provided KMALLOC_MAX_SIZE instead of it's own,
bogus, definition. From Cong Wang.
19) Fix deadlocks in FEC driver by moving TX reclaim into NAPI poll,
from Frank Li. Also, fix a build error introduced in the merge
window.
20) Fix bogus purging of default routes in ipv6, from Lorenzo Colitti.
21) Don't double count RTT measurements when we leave the TCP receive
fast path, from Neal Cardwell."
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (61 commits)
tcp: fix double-counted receiver RTT when leaving receiver fast path
CAIF: fix sparse warning for caif_usb
rds: simplify a warning message
net: fec: fix build error in no MXC platform
net: ipv6: Don't purge default router if accept_ra=2
net: fec: put tx to napi poll function to fix dead lock
sctp: use KMALLOC_MAX_SIZE instead of its own MAX_KMALLOC_SIZE
rds: limit the size allocated by rds_message_alloc()
MAINTAINERS: remove eexpress
MAINTAINERS: remove drivers/net/wan/cycx*
MAINTAINERS: remove 3c505
caif_dev: fix sparse warnings for caif_flow_cb
ax88179_178a: ASIX AX88179_178A USB 3.0/2.0 to gigabit ethernet adapter driver
sctp: use the passed in gfp flags instead GFP_KERNEL
ipv[4|6]: correct dropwatch false positive in local_deliver_finish
l2tp: Restore socket refcount when sendmsg succeeds
net/phy: micrel: Disable asymmetric pause for KSZ9021
bgmac: omit the fcs
phy: Fix phy_device_free memory leak
bnx2x: Fix KR2 work-around condition
...
The sendmsg() syscall handler for PPPoL2TP doesn't decrease the socket
reference counter after successful transmissions. Any successful
sendmsg() call from userspace will then increase the reference counter
forever, thus preventing the kernel's session and tunnel data from
being freed later on.
The problem only happens when writing directly on L2TP sockets.
PPP sockets attached to L2TP are unaffected as the PPP subsystem
uses pppol2tp_xmit() which symmetrically increase/decrease reference
counters.
This patch adds the missing call to sock_put() before returning from
pppol2tp_sendmsg().
Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
