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  1. 07 1月, 2013 1 次提交
  3. 05 1月, 2013 5 次提交
  5. 04 1月, 2013 3 次提交
  7. 30 12月, 2012 1 次提交
    • D
      net: filter: return -EINVAL if BPF_S_ANC* operation is not supported · aa1113d9
      由 Daniel Borkmann 提交于 
      Currently, we return -EINVAL for malformed or wrong BPF filters.
However, this is not done for BPF_S_ANC* operations, which makes it
more difficult to detect if it's actually supported or not by the
BPF machine. Therefore, we should also return -EINVAL if K is within
the SKF_AD_OFF universe and the ancillary operation did not match.

Why exactly is it needed? If tools such as libpcap/tcpdump want to
make use of new ancillary operations (like filtering VLAN in kernel
space), there is currently no sane way to test if this feature /
BPF_S_ANC* op is present or not, since no error is returned. This
patch will make life easier for that and allow for a proper usage
for user space applications.

There was concern, if this patch will break userland. Short answer: Yes
and no. Long answer: It will "break" only for code that calls ...

  { BPF_LD | BPF_(W|H|B) | BPF_ABS, 0, 0, <K> },

... where <K> is in [0xfffff000, 0xffffffff] _and_ <K> is *not* an
ancillary. And here comes the BUT: assuming some *old* code will have
such an instruction where <K> is between [0xfffff000, 0xffffffff] and
it doesn't know ancillary operations, then this will give a
non-expected / unwanted behavior as well (since we do not return the
BPF machine with 0 after a failed load_pointer(), which was the case
before introducing ancillary operations, but load sth. into the
accumulator instead, and continue with the next instruction, for
instance). Thus, user space code would already have been broken by
introducing ancillary operations into the BPF machine per se. Code
that does such a direct load, e.g. "load word at packet offset
0xffffffff into accumulator" ("ld [0xffffffff]") is quite broken,
isn't it? The whole assumption of ancillary operations is that no-one
intentionally calls things like "ld [0xffffffff]" and expect this
word to be loaded from such a packet offset. Hence, we can also safely
make use of this feature testing patch and facilitate application
development. Therefore, at least from this patch onwards, we have
*for sure* a check whether current or in future implemented BPF_S_ANC*
ops are supported in the kernel. Patch was tested on x86_64.

(Thanks to Eric for the previous review.)

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Reported-by: NAni Sinha <ani@aristanetworks.com>
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      aa1113d9
  9. 29 12月, 2012 5 次提交
  11. 22 12月, 2012 2 次提交
  13. 15 12月, 2012 1 次提交
    • E
      userns: Require CAP_SYS_ADMIN for most uses of setns. · 5e4a0847
      由 Eric W. Biederman 提交于 
      Andy Lutomirski <luto@amacapital.net> found a nasty little bug in
the permissions of setns.  With unprivileged user namespaces it
became possible to create new namespaces without privilege.

However the setns calls were relaxed to only require CAP_SYS_ADMIN in
the user nameapce of the targed namespace.

Which made the following nasty sequence possible.

pid = clone(CLONE_NEWUSER | CLONE_NEWNS);
if (pid == 0) { /* child */
	system("mount --bind /home/me/passwd /etc/passwd");
}
else if (pid != 0) { /* parent */
	char path[PATH_MAX];
	snprintf(path, sizeof(path), "/proc/%u/ns/mnt");
	fd = open(path, O_RDONLY);
	setns(fd, 0);
	system("su -");
}

Prevent this possibility by requiring CAP_SYS_ADMIN
in the current user namespace when joing all but the user namespace.
Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
      5e4a0847
  15. 12 12月, 2012 3 次提交
  17. 11 12月, 2012 1 次提交
  19. 09 12月, 2012 2 次提交
  21. 08 12月, 2012 2 次提交
  23. 06 12月, 2012 2 次提交
  25. 05 12月, 2012 1 次提交
    • S
      net: dev_change_net_namespace: send a KOBJ_REMOVED/KOBJ_ADD · 4e66ae2e
      由 Serge Hallyn 提交于 
      When a new nic is created in namespace ns1, the kernel sends a KOBJ_ADD uevent
to ns1.  When the nic is moved to ns2, we only send a KOBJ_MOVE to ns2, and
nothing to ns1.

This patch changes that behavior so that when moving a nic from ns1 to ns2, we
send a KOBJ_REMOVED to ns1 and KOBJ_ADD to ns2.  (The KOBJ_MOVE is still
sent to ns2).

The effects of this can be seen when starting and stopping containers in
an upstart based host.  Lxc will create a pair of veth nics, the kernel
sends KOBJ_ADD, and upstart starts network-instance jobs for each.  When
one nic is moved to the container, because no KOBJ_REMOVED event is
received, the network-instance job for that veth never goes away.  This
was reported at https://bugs.launchpad.net/ubuntu/+source/lxc/+bug/1065589
With this patch the networ-instance jobs properly go away.

The other oddness solved here is that if a nic is passed into a running
upstart-based container, without this patch no network-instance job is
started in the container.  But when the container creates a new nic
itself (ip link add new type veth) then network-interface jobs are
created.  With this patch, behavior comes in line with a regular host.

v2: also send KOBJ_ADD to new netns.  There will then be a
_MOVE event from the device_rename() call, but that should
be innocuous.
Signed-off-by: NSerge Hallyn <serge.hallyn@canonical.com>
Acked-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: NDaniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      4e66ae2e
  27. 01 12月, 2012 1 次提交
    • R
      rtnelink: remove unused parameter from rtnl_create_link(). · c0713563
      由 Rami Rosen 提交于 
      This patch removes an unused parameter (src_net) from rtnl_create_link()
method and from the method single invocation, in veth.
This parameter was used in the past when calling
ops->get_tx_queues(src_net, tb) in rtnl_create_link().
The get_tx_queues() member of rtnl_link_ops was replaced by two methods,
get_num_tx_queues() and get_num_rx_queues(), which do not get any
parameter. This was done in commit d40156aa by
Jiri Pirko ("rtnl: allow to specify different num for rx and tx queue count").
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c0713563
  29. 30 11月, 2012 1 次提交
  31. 27 11月, 2012 1 次提交
    • B
      sockopt: Change getsockopt() of SO_BINDTODEVICE to return an interface name · c91f6df2
      由 Brian Haley 提交于 
      Instead of having the getsockopt() of SO_BINDTODEVICE return an index, which
will then require another call like if_indextoname() to get the actual interface
name, have it return the name directly.

This also matches the existing man page description on socket(7) which mentions
the argument being an interface name.

If the value has not been set, zero is returned and optlen will be set to zero
to indicate there is no interface name present.

Added a seqlock to protect this code path, and dev_ifname(), from someone
changing the device name via dev_change_name().

v2: Added seqlock protection while copying device name.

v3: Fixed word wrap in patch.
Signed-off-by: NBrian Haley <brian.haley@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c91f6df2
  33. 22 11月, 2012 6 次提交
  35. 21 11月, 2012 1 次提交
  37. 20 11月, 2012 1 次提交
    • E
      proc: Usable inode numbers for the namespace file descriptors. · 98f842e6
      由 Eric W. Biederman 提交于 
      Assign a unique proc inode to each namespace, and use that
inode number to ensure we only allocate at most one proc
inode for every namespace in proc.

A single proc inode per namespace allows userspace to test
to see if two processes are in the same namespace.

This has been a long requested feature and only blocked because
a naive implementation would put the id in a global space and
would ultimately require having a namespace for the names of
namespaces, making migration and certain virtualization tricks
impossible.

We still don't have per superblock inode numbers for proc, which
appears necessary for application unaware checkpoint/restart and
migrations (if the application is using namespace file descriptors)
but that is now allowd by the design if it becomes important.

I have preallocated the ipc and uts initial proc inode numbers so
their structures can be statically initialized.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      98f842e6