Pull gcc plugins update from Kees Cook:
"This adds a new gcc plugin named "latent_entropy". It is designed to
extract as much possible uncertainty from a running system at boot
time as possible, hoping to capitalize on any possible variation in
CPU operation (due to runtime data differences, hardware differences,
SMP ordering, thermal timing variation, cache behavior, etc).
At the very least, this plugin is a much more comprehensive example
for how to manipulate kernel code using the gcc plugin internals"
* tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
latent_entropy: Mark functions with __latent_entropy
gcc-plugins: Add latent_entropy plugin
The "vf_vlan_info" struct ends with a 2 byte struct hole so we have to
memset it to ensure that no stack information is revealed to user space.
Fixes: 79aab093a0 ('net: Update API for VF vlan protocol 802.1ad support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The __latent_entropy gcc attribute can be used only on functions and
variables. If it is on a function then the plugin will instrument it for
gathering control-flow entropy. If the attribute is on a variable then
the plugin will initialize it with random contents. The variable must
be an integer, an integer array type or a structure with integer fields.
These specific functions have been selected because they are init
functions (to help gather boot-time entropy), are called at unpredictable
times, or they have variable loops, each of which provide some level of
latent entropy.
Signed-off-by: Emese Revfy <re.emese@gmail.com>
[kees: expanded commit message]
Signed-off-by: Kees Cook <keescook@chromium.org>
Merge updates from Andrew Morton:
- fsnotify updates
- ocfs2 updates
- all of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (127 commits)
console: don't prefer first registered if DT specifies stdout-path
cred: simpler, 1D supplementary groups
CREDITS: update Pavel's information, add GPG key, remove snail mail address
mailmap: add Johan Hovold
.gitattributes: set git diff driver for C source code files
uprobes: remove function declarations from arch/{mips,s390}
spelling.txt: "modeled" is spelt correctly
nmi_backtrace: generate one-line reports for idle cpus
arch/tile: adopt the new nmi_backtrace framework
nmi_backtrace: do a local dump_stack() instead of a self-NMI
nmi_backtrace: add more trigger_*_cpu_backtrace() methods
min/max: remove sparse warnings when they're nested
Documentation/filesystems/proc.txt: add more description for maps/smaps
mm, proc: fix region lost in /proc/self/smaps
proc: fix timerslack_ns CAP_SYS_NICE check when adjusting self
proc: add LSM hook checks to /proc/<tid>/timerslack_ns
proc: relax /proc/<tid>/timerslack_ns capability requirements
meminfo: break apart a very long seq_printf with #ifdefs
seq/proc: modify seq_put_decimal_[u]ll to take a const char *, not char
proc: faster /proc/*/status
...
Pull VFS splice updates from Al Viro:
"There's a bunch of branches this cycle, both mine and from other folks
and I'd rather send pull requests separately.
This one is the conversion of ->splice_read() to ITER_PIPE iov_iter
(and introduction of such). Gets rid of a lot of code in fs/splice.c
and elsewhere; there will be followups, but these are for the next
cycle... Some pipe/splice-related cleanups from Miklos in the same
branch as well"
* 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
pipe: fix comment in pipe_buf_operations
pipe: add pipe_buf_steal() helper
pipe: add pipe_buf_confirm() helper
pipe: add pipe_buf_release() helper
pipe: add pipe_buf_get() helper
relay: simplify relay_file_read()
switch default_file_splice_read() to use of pipe-backed iov_iter
switch generic_file_splice_read() to use of ->read_iter()
new iov_iter flavour: pipe-backed
fuse_dev_splice_read(): switch to add_to_pipe()
skb_splice_bits(): get rid of callback
new helper: add_to_pipe()
splice: lift pipe_lock out of splice_to_pipe()
splice: switch get_iovec_page_array() to iov_iter
splice_to_pipe(): don't open-code wakeup_pipe_readers()
consistent treatment of EFAULT on O_DIRECT read/write
Pull namespace updates from Eric Biederman:
"This set of changes is a number of smaller things that have been
overlooked in other development cycles focused on more fundamental
change. The devpts changes are small things that were a distraction
until we managed to kill off DEVPTS_MULTPLE_INSTANCES. There is an
trivial regression fix to autofs for the unprivileged mount changes
that went in last cycle. A pair of ioctls has been added by Andrey
Vagin making it is possible to discover the relationships between
namespaces when referring to them through file descriptors.
The big user visible change is starting to add simple resource limits
to catch programs that misbehave. With namespaces in general and user
namespaces in particular allowing users to use more kinds of
resources, it has become important to have something to limit errant
programs. Because the purpose of these limits is to catch errant
programs the code needs to be inexpensive to use as it always on, and
the default limits need to be high enough that well behaved programs
on well behaved systems don't encounter them.
To this end, after some review I have implemented per user per user
namespace limits, and use them to limit the number of namespaces. The
limits being per user mean that one user can not exhause the limits of
another user. The limits being per user namespace allow contexts where
the limit is 0 and security conscious folks can remove from their
threat anlysis the code used to manage namespaces (as they have
historically done as it root only). At the same time the limits being
per user namespace allow other parts of the system to use namespaces.
Namespaces are increasingly being used in application sand boxing
scenarios so an all or nothing disable for the entire system for the
security conscious folks makes increasing use of these sandboxes
impossible.
There is also added a limit on the maximum number of mounts present in
a single mount namespace. It is nontrivial to guess what a reasonable
system wide limit on the number of mount structure in the kernel would
be, especially as it various based on how a system is using
containers. A limit on the number of mounts in a mount namespace
however is much easier to understand and set. In most cases in
practice only about 1000 mounts are used. Given that some autofs
scenarious have the potential to be 30,000 to 50,000 mounts I have set
the default limit for the number of mounts at 100,000 which is well
above every known set of users but low enough that the mount hash
tables don't degrade unreaonsably.
These limits are a start. I expect this estabilishes a pattern that
other limits for resources that namespaces use will follow. There has
been interest in making inotify event limits per user per user
namespace as well as interest expressed in making details about what
is going on in the kernel more visible"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (28 commits)
autofs: Fix automounts by using current_real_cred()->uid
mnt: Add a per mount namespace limit on the number of mounts
netns: move {inc,dec}_net_namespaces into #ifdef
nsfs: Simplify __ns_get_path
tools/testing: add a test to check nsfs ioctl-s
nsfs: add ioctl to get a parent namespace
nsfs: add ioctl to get an owning user namespace for ns file descriptor
kernel: add a helper to get an owning user namespace for a namespace
devpts: Change the owner of /dev/pts/ptmx to the mounter of /dev/pts
devpts: Remove sync_filesystems
devpts: Make devpts_kill_sb safe if fsi is NULL
devpts: Simplify devpts_mount by using mount_nodev
devpts: Move the creation of /dev/pts/ptmx into fill_super
devpts: Move parse_mount_options into fill_super
userns: When the per user per user namespace limit is reached return ENOSPC
userns; Document per user per user namespace limits.
mntns: Add a limit on the number of mount namespaces.
netns: Add a limit on the number of net namespaces
cgroupns: Add a limit on the number of cgroup namespaces
ipcns: Add a limit on the number of ipc namespaces
...
This is a respin of a patch to fix a relatively easily reproducible kernel
panic related to the all_adj_list handling for netdevs in recent kernels.
The following sequence of commands will reproduce the issue:
ip link add link eth0 name eth0.100 type vlan id 100
ip link add link eth0 name eth0.200 type vlan id 200
ip link add name testbr type bridge
ip link set eth0.100 master testbr
ip link set eth0.200 master testbr
ip link add link testbr mac0 type macvlan
ip link delete dev testbr
This creates an upper/lower tree of (excuse the poor ASCII art):
/---eth0.100-eth0
mac0-testbr-
\---eth0.200-eth0
When testbr is deleted, the all_adj_lists are walked, and eth0 is deleted twice from
the mac0 list. Unfortunately, during setup in __netdev_upper_dev_link, only one
reference to eth0 is added, so this results in a panic.
This change adds reference count propagation so things are handled properly.
Matthias Schiffer reported a similar crash in batman-adv:
https://github.com/freifunk-gluon/gluon/issues/680https://www.open-mesh.org/issues/247
which this patch also seems to resolve.
Signed-off-by: Andrew Collins <acollins@cradlepoint.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_vlan_pop/push were too generic, trying to support the cases where
skb->data is at mac header, and cases where skb->data is arbitrarily
elsewhere.
Supporting an arbitrary skb->data was complex and bogus:
- It failed to unwind skb->data to its original location post actual
pop/push.
(Also, semantic is not well defined for unwinding: If data was into
the eth header, need to use same offset from start; But if data was
at network header or beyond, need to adjust the original offset
according to the push/pull)
- It mangled the rcsum post actual push/pop, without taking into account
that the eth bytes might already have been pulled out of the csum.
Most callers (ovs, bpf) already had their skb->data at mac_header upon
invoking skb_vlan_pop/push.
Last caller that failed to do so (act_vlan) has been recently fixed.
Therefore, to simplify things, no longer support arbitrary skb->data
inputs for skb_vlan_pop/push().
skb->data is expected to be exactly at mac_header; WARN otherwise.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Pravin Shelar <pshelar@ovn.org>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
since pipe_lock is the outermost now, we don't need to drop/regain
socket locks around the call of splice_to_pipe() from skb_splice_bits(),
which kills the need to have a socket-specific callback; we can just
call splice_to_pipe() and be done with that.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
With the newly added support for IFLA_VF_VLAN_LIST netlink messages,
we get a warning about potential uninitialized variable use in
the parsing of the user input when enabling the -Wmaybe-uninitialized
warning:
net/core/rtnetlink.c: In function 'do_setvfinfo':
net/core/rtnetlink.c:1756:9: error: 'ivvl$' may be used uninitialized in this function [-Werror=maybe-uninitialized]
I have not been able to prove whether it is possible to arrive in
this code with an empty IFLA_VF_VLAN_LIST block, but if we do,
then ndo_set_vf_vlan gets called with uninitialized arguments.
This adds an explicit check for an empty list, making it obvious
to the reader and the compiler that this cannot happen.
Fixes: 79aab093a0 ("net: Update API for VF vlan protocol 802.1ad support")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 879c7220e8 ("net: pktgen: Observe needed_headroom
of the device") increased the 'pkt_overhead' field value by
LL_RESERVED_SPACE.
As a side effect the generated packet size, computed as:
/* Eth + IPh + UDPh + mpls */
datalen = pkt_dev->cur_pkt_size - 14 - 20 - 8 -
pkt_dev->pkt_overhead;
is decreased by the same value.
The above changed slightly the behavior of existing pktgen users,
and made the procfs interface somewhat inconsistent.
Fix it by restoring the previous pkt_overhead value and using
LL_RESERVED_SPACE as extralen in skb allocation.
Also, change pktgen_alloc_skb() to only partially reserve
the headroom to allow the caller to prefetch from ll header
start.
v1 -> v2:
- fixed some typos in the comments
Fixes: 879c7220e8 ("net: pktgen: Observe needed_headroom of the device")
Suggested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 900f65d361 ("tcp: move duplicate code from
tcp_v4_init_sock()/tcp_v6_init_sock()") we no longer need
to export sk_stream_write_space()
From: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/netfilter/core.c
net/netfilter/nf_tables_netdev.c
Resolve two conflicts before pull request for David's net-next tree:
1) Between c73c248490 ("netfilter: nf_tables_netdev: remove redundant
ip_hdr assignment") from the net tree and commit ddc8b6027a
("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").
2) Between e8bffe0cf9 ("net: Add _nf_(un)register_hooks symbols") and
Aaron Conole's patches to replace list_head with single linked list.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit ensures that the rcu read-side lock is held while the
ingress hook is called. This ensures that a call to nf_hook_slow (and
ultimately nf_ingress) will be read protected.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Introduce new rtnl UAPI that exposes a list of vlans per VF, giving
the ability for user-space application to specify it for the VF, as an
option to support 802.1ad.
We adjusted IP Link tool to support this option.
For future use cases, the new UAPI supports multiple vlans. For now we
limit the list size to a single vlan in kernel.
Add IFLA_VF_VLAN_LIST in addition to IFLA_VF_VLAN to keep backward
compatibility with older versions of IP Link tool.
Add a vlan protocol parameter to the ndo_set_vf_vlan callback.
We kept 802.1Q as the drivers' default vlan protocol.
Suitable ip link tool command examples:
Set vf vlan protocol 802.1ad:
ip link set eth0 vf 1 vlan 100 proto 802.1ad
Set vf to VST (802.1Q) mode:
ip link set eth0 vf 1 vlan 100 proto 802.1Q
Or by omitting the new parameter
ip link set eth0 vf 1 vlan 100
Signed-off-by: Moshe Shemesh <moshe@mellanox.com>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With the newly enforced limit on the number of namespaces,
we get a build warning if CONFIG_NETNS is disabled:
net/core/net_namespace.c:273:13: error: 'dec_net_namespaces' defined but not used [-Werror=unused-function]
net/core/net_namespace.c:268:24: error: 'inc_net_namespaces' defined but not used [-Werror=unused-function]
This moves the two added functions inside the #ifdef that guards
their callers.
Fixes: 703286608a ("netns: Add a limit on the number of net namespaces")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Add a small helper that complements 36bbef52c7 ("bpf: direct packet
write and access for helpers for clsact progs") for invalidating the
current skb->hash after mangling on headers via direct packet write.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Same motivation as in commit 80b48c4457 ("bpf: don't use raw processor
id in generic helper"), but this time for XDP typed programs. Thus, allow
for preemption checks when we have DEBUG_PREEMPT enabled, and otherwise
use the raw variant.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We need to use skb_to_full_sk() helper introduced in commit bd5eb35f16
("xfrm: take care of request sockets") as otherwise we miss tcp synack
messages, since ownership is on request socket and therefore it would
miss the sk_fullsock() check. Use skb_to_full_sk() as also done similarly
in the bpf_get_cgroup_classid() helper via 2309236c13 ("cls_cgroup:
get sk_classid only from full sockets") fix to not let this fall through.
Fixes: 4a482f34af ("cgroup: bpf: Add bpf_skb_in_cgroup_proto")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Andrey Vagin <avagin@openvz.org>
Each namespace has an owning user namespace and now there is not way
to discover these relationships.
Pid and user namepaces are hierarchical. There is no way to discover
parent-child relationships too.
Why we may want to know relationships between namespaces?
One use would be visualization, in order to understand the running
system. Another would be to answer the question: what capability does
process X have to perform operations on a resource governed by namespace
Y?
One more use-case (which usually called abnormal) is checkpoint/restart.
In CRIU we are going to dump and restore nested namespaces.
There [1] was a discussion about which interface to choose to determing
relationships between namespaces.
Eric suggested to add two ioctl-s [2]:
> Grumble, Grumble. I think this may actually a case for creating ioctls
> for these two cases. Now that random nsfs file descriptors are bind
> mountable the original reason for using proc files is not as pressing.
>
> One ioctl for the user namespace that owns a file descriptor.
> One ioctl for the parent namespace of a namespace file descriptor.
Here is an implementaions of these ioctl-s.
$ man man7/namespaces.7
...
Since Linux 4.X, the following ioctl(2) calls are supported for
namespace file descriptors. The correct syntax is:
fd = ioctl(ns_fd, ioctl_type);
where ioctl_type is one of the following:
NS_GET_USERNS
Returns a file descriptor that refers to an owning user names‐
pace.
NS_GET_PARENT
Returns a file descriptor that refers to a parent namespace.
This ioctl(2) can be used for pid and user namespaces. For
user namespaces, NS_GET_PARENT and NS_GET_USERNS have the same
meaning.
In addition to generic ioctl(2) errors, the following specific ones
can occur:
EINVAL NS_GET_PARENT was called for a nonhierarchical namespace.
EPERM The requested namespace is outside of the current namespace
scope.
[1] https://lkml.org/lkml/2016/7/6/158
[2] https://lkml.org/lkml/2016/7/9/101
Changes for v2:
* don't return ENOENT for init_user_ns and init_pid_ns. There is nothing
outside of the init namespace, so we can return EPERM in this case too.
> The fewer special cases the easier the code is to get
> correct, and the easier it is to read. // Eric
Changes for v3:
* rename ns->get_owner() to ns->owner(). get_* usually means that it
grabs a reference.
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Cc: "W. Trevor King" <wking@tremily.us>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Serge Hallyn <serge.hallyn@canonical.com>
Return -EPERM if an owning user namespace is outside of a process
current user namespace.
v2: In a first version ns_get_owner returned ENOENT for init_user_ns.
This special cases was removed from this version. There is nothing
outside of init_user_ns, so we can return EPERM.
v3: rename ns->get_owner() to ns->owner(). get_* usually means that it
grabs a reference.
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
The current error codes returned when a the per user per user
namespace limit are hit (EINVAL, EUSERS, and ENFILE) are wrong. I
asked for advice on linux-api and it we made clear that those were
the wrong error code, but a correct effor code was not suggested.
The best general error code I have found for hitting a resource limit
is ENOSPC. It is not perfect but as it is unambiguous it will serve
until someone comes up with a better error code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Fix 'skb_vlan_pop' to use eth_type_vlan instead of directly comparing
skb->protocol to ETH_P_8021Q or ETH_P_8021AD.
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Reviewed-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds
Dan Carpenter
Emese Revfy
Johannes Weiner
Andrew Collins
Shmulik Ladkani
Al Viro
Arnd Bergmann
Paolo Abeni
Eric Dumazet
Pablo Neira Ayuso
Aaron Conole
Moshe Shemesh
Daniel Borkmann
David S. Miller
Eric W. Biederman
Andrey Vagin
Shmulik Ladkani