Commit graph

766102 commits

Author SHA1 Message Date
David Sterba
010a47bde9 btrfs: add proper safety check before resuming dev-replace
The device replace is paused by unmount or read only remount, and
resumed on next mount or write remount.

The exclusive status should be checked properly as it's a global
invariant and we must not allow 2 operations run. In this case, the
balance can be also paused and resumed under same conditions. It's
always checked first so dev-replace could see the EXCL_OP already taken,
BUT, the ioctl would never let start both at the same time.

Replace the WARN_ON with message and return 0, indicating no error as
this is purely theoretical and the user will be informed. Resolving that
manually should be possible by waiting for the other operation to finish
or cancel the paused state.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
a17c95df4c btrfs: move clearing of EXCL_OP out of __cancel_balance
Make the clearning visible in the callers so we can pair it with the
test_and_set part.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
72b81abf95 btrfs: move volume_mutex to callers of btrfs_rm_device
Move locking and unlocking next to the BTRFS_FS_EXCL_OP bit manipulation
so it's obvious that the two happen at the same time.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
d48f39d5a5 btrfs: move btrfs_init_dev_replace_tgtdev to dev-replace.c and make static
The function logically belongs there and there's only a single caller,
no need to export it. No code changes.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:24 +02:00
David Sterba
a425f9d475 btrfs: export and rename free_device
The function will be used outside of volumes.c, the allocation
btrfs_alloc_device is also exported.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:23 +02:00
David Sterba
6fc4749d25 btrfs: make success path out of btrfs_init_dev_replace_tgtdev more clear
This is a preparatory cleanup that will make clear that the only
successful way out of btrfs_init_dev_replace_tgtdev will also set the
device_out to a valid pointer. With this guarantee, the callers can be
simplified.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:23 +02:00
David Sterba
00251a527a btrfs: squeeze btrfs_dev_replace_continue_on_mount to its caller
The function is called once and is fairly small, we can merge it with
the caller.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:22 +02:00
Anand Jain
b518519713 btrfs: cleanup btrfs_rm_device() promote fs_devices pointer
This function uses fs_info::fs_devices number of time, however we
declare and use it only at the end, instead do it in the beginning of
the function and use it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:22 +02:00
Anand Jain
636d2c9d63 btrfs: cleanup find_device() drop list_head pointer
find_device() declares struct list_head *head pointer and used only once,
instead just use it directly.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:22 +02:00
Anand Jain
897fb5734a btrfs: rename __btrfs_open_devices to open_fs_devices
__btrfs_open_devices() is un-exported drop __ prefix and rename it to
open_fs_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Anand Jain
0226e0eb65 btrfs: rename __btrfs_close_devices to close_fs_devices
__btrfs_close_devices() is un-exported, drop the __ prefix and rename it
to close_fs_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Anand Jain
f117e290e8 btrfs: cleanup __btrfs_open_devices() drop head pointer
__btrfs_open_devices() declares struct list_head *head, however head is
used only once, instead use btrfs_fs_devices::devices directly.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Anand Jain
c4babc5e38 btrfs: rename struct btrfs_fs_devices::list
btrfs_fs_devices::list is the list of BTRFS fsid in the kernel, a generic
name 'list' makes it's search very difficult, rename it to fs_list.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:21 +02:00
Nikolay Borisov
be97f133b3 btrfs: Drop fs_info parameter from btrfs_merge_delayed_refs
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
f033798d12 btrfs: Drop fs_info parameter from add_delayed_data_ref
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
1acda0c289 btrfs: Drop add_delayed_ref_head fs_info parameter
It's provided by the transaction handle.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
40012f96b6 btrfs: Remove btrfs_wait_and_free_delalloc_work
This function is called from only 1 place and is effectively a wrapper
over wait_completion/kfree. It doesn't really bring any value having
those two calls in a separate function. Just open code it and remove it.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
8ae225a8a4 btrfs: Remove tree argument from extent_writepages
It can be directly referenced from the passed address_space so do that.
No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:20 +02:00
Nikolay Borisov
81f1d39035 btrfs: Use list_empty instead of list_empty_careful
list_empty_careful usually is a signal of something tricky going on. Its
usage in btrfs is actually not needed since both lists it's used on are
local to a function and cannot be modified concurrently. So switch to
plain list_empty. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Nikolay Borisov
2a3ff0adc9 btrfs: Remove redundant tree argument from extent_readpages
This function is called only from btrfs_readpage and is already passed
the mapping. Simplify its signature by moving the code obtaining
reference to the extent tree in the function. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Nikolay Borisov
29c68b2de9 btrfs: Remove map argument from try_release_extent_state
It's not used in the function so just remove it. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Nikolay Borisov
477a30ba5f btrfs: Sink extent_tree arguments in try_release_extent_mapping
This function already gets the page from which the two extent trees
are referenced. Simplify its signature by moving the code getting the
trees inside the function. No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:19 +02:00
Misono Tomohiro
a79a464d56 btrfs: Allow rmdir(2) to delete an empty subvolume
Change the behavior of rmdir(2) and allow it to delete an empty
subvolume by using btrfs_delete_subvolume() which is used by
btrfs_ioctl_snap_destroy().

This is a change in behaviour and has been requested by users. Deleting
the subvolume by ioctl requires root permissions while the rmdir way
does works with standard tools and syscalls for all users that can
access the subvolume.

The main usecase is to allow 'rm -rf /path/with/subvols' to simply work.
We were not able to find any nasty usability surprises, the intention is
to do the destructive rm. Without allowing rmdir, this would have to be
followed by the ioctl subvolume deletion, which is more of an annoyance.

Implementation details:

The required lock for @dir and inode of @dentry is already acquired in
vfs layer.

We need some check before deleting a subvolume. Permission check is done
in vfs layer, emptiness check is in btrfs_rmdir() and additional check
(i.e. neither the subvolume is a default subvolume nor send is in progress)
is in btrfs_delete_subvolume().

Note that in btrfs_ioctl_snap_destroy(), d_delete() is called after
btrfs_delete_subvolume(). For rmdir(2), d_delete() is called in vfs
layer later.

Tested-by: Goffredo Baroncelli <kreijack@inwind.it>
Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Misono Tomohiro
f60a2364a4 btrfs: Factor out the main deletion process from btrfs_ioctl_snap_destroy()
Factor out the second half of btrfs_ioctl_snap_destroy() as
btrfs_delete_subvolume(), which performs some subvolume specific checks
before deletion:

1. send is not in progress
2. the subvolume is not the default subvolume
3. the subvolume does not contain other subvolumes

and actual deletion process. btrfs_delete_subvolume() requires
inode_lock for both @dir and inode of @dentry. The remaining part of
btrfs_ioctl_snap_destroy() is mainly permission checks.

Note that call of d_delete() is not included in btrfs_delete_subvolume()
as this function will also be used by btrfs_rmdir() to delete an empty
subvolume and in that case d_delete() is called in VFS layer.

As a result, btrfs_unlink_subvol() and may_destroy_subvol()
become static functions. No functional changes.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Misono Tomohiro
ec42f16734 btrfs: Move may_destroy_subvol() from ioctl.c to inode.c
This is a preparation work to refactor btrfs_ioctl_snap_destroy()
and to allow rmdir(2) to delete an empty subvolume.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor update of the function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Howard McLauchlan
3b079a919a btrfs: remove unused le_test_bit()
With commit b18253ec57c0 ("btrfs: optimize free space tree bitmap
conversion"), there are no more callers to le_test_bit(). This patch
removes le_test_bit().

Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Howard McLauchlan
a565971ff3 btrfs: optimize free space tree bitmap conversion
Presently, convert_free_space_to_extents() does a linear scan of the
bitmap. We can speed this up with find_next_{bit,zero_bit}_le().

This patch replaces the linear scan with find_next_{bit,zero_bit}_le().
Testing shows a 20-33% decrease in execution time for
convert_free_space_to_extents().

Since we change bitmap to be unsigned long, we have to do some casting
for the bitmap cursor. In le_bitmap_set() it makes sense to use u8, as
we are doing bit operations. Everywhere else, we're just using it for
pointer arithmetic and not directly accessing it, so char seems more
appropriate.

Suggested-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
Howard McLauchlan
6faa8f475e btrfs: clean up le_bitmap_{set, clear}()
le_bitmap_set() is only used by free-space-tree, so move it there and
make it static. le_bitmap_clear() is not used, so remove it.

Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:18 +02:00
David Sterba
f46b24c945 btrfs: use fs_info for btrfs_handle_em_exist tracepoint
We really want to know to which filesystem the extent map events belong,
but as it cannot be reached from the extent_map pointers, we need to
pass it down the callchain.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:17 +02:00
David Sterba
0e08eb9b1c btrfs: tests: pass fs_info to extent_map tests
Preparatory work to pass fs_info to btrfs_add_extent_mapping so we can
get a better tracepoint message. Extent maps do not need fs_info for
anything so we only add a dummy one without any other initialization.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:17 +02:00
David Sterba
2e63e62d98 btrfs: tracepoints, use extended format with UUID where possible
Most of the strings are prefixed by the UUID of the filesystem that
generates the message, however there are a few events that still
opencode the macro magic and can be converted to the common macros.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:17 +02:00
David Sterba
79bcb71a5b btrfs: tracepoints, fix whitespace in strings
The preferred style is to avoid spaces between key and value and no
commas between key=values.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:17 +02:00
David Sterba
8eec846308 btrfs: tracepoints, drop unnecessary ULL casts
The (unsigned long long) casts are not necessary since long ago.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
David Sterba
5439c7f54c btrfs: tracepoints, use %llu instead of %Lu
For consistency, use the %llu form.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
David Sterba
f8f8e18951 btrfs: tracepoints, use correct type for inode number
The size of ino_t depends on 32/64bit architecture type. Btrfs stores
the full 64bit inode anyway so we should use it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
Nikolay Borisov
57f1642ec3 btrfs: Consolidate error checking for btrfs_alloc_chunk
The second if is really a subcase of ret being less than 0. So
introduce a generic if (ret < 0) check, and inside have another if
which explicitly handles the -ENOSPC and any other errors. No
functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
Nikolay Borisov
1e7a14211b btrfs: Fix lock release order
Locks should generally be released in the oppposite order they are
acquired. Generally lock acquisiton ordering is used to ensure
deadlocks don't happen. However, as becomes more complicated it's
best to also maintain proper unlock order so as to avoid possible dead
locks. This was found by code inspection and doesn't necessarily lead
to a deadlock scenario.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:16 +02:00
Nikolay Borisov
b25f0d0012 btrfs: Use while loop instead of labels in __endio_write_update_ordered
Currently __endio_write_update_ordered uses labels to implement
what is essentially a simple while loop. This makes the code more
cumbersome to follow than it actually has to be. No functional
changes. No xfstest regressions were found during testing.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:15 +02:00
Anand Jain
89595e80de btrfs: add comment about BTRFS_FS_EXCL_OP
Adds comments about BTRFS_FS_EXCL_OP to existing comments
about the device locks.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor updates ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-05-28 18:07:15 +02:00
Daniel Borkmann
f198222f05 Merge branch 'bpf-sendmsg-hook'
Andrey Ignatov says:

====================
v3 -> v4:
* handle static key correctly for CONFIG_CGROUP_BPF=n.

v2 -> v3:
* place BPF logic under static key in udp_sendmsg, udpv6_sendmsg;
* rebase.

v1 -> v2:
* return ENOTSUPP if bpf_prog rewrote IPv6-only with IPv4-mapped IPv6;
* add test for IPv4-mapped IPv6 use-case;
* fix build for CONFIG_CGROUP_BPF=n;
* rebase.

This path set adds BPF hooks for sys_sendmsg similar to existing hooks for
sys_bind and sys_connect.

Hooks allow to override source IP (including the case when it's set via
cmsg(3)) and destination IP:port for unconnected UDP (slow path). TCP and
connected UDP (fast path) are not affected. This makes UDP support
complete: connected UDP is handled by sys_connect hooks, unconnected by
sys_sendmsg ones.

Similar to sys_connect hooks, sys_sendmsg ones can be used to make system
calls such as sendmsg(2) and sendto(2) return EPERM.

Please see patch 0002 for more details.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:43:32 +02:00
Andrey Ignatov
04b6ab7312 selftests/bpf: Selftest for sys_sendmsg hooks
Add selftest for BPF_CGROUP_UDP4_SENDMSG and BPF_CGROUP_UDP6_SENDMSG
attach types.

Try to sendmsg(2) to specific IP:port and test that:
* source IP is overridden as expected.
* remote IP:port pair is overridden as expected;

Both UDPv4 and UDPv6 are tested.

Output:
  # test_sock_addr.sh 2>/dev/null
  Wait for testing IPv4/IPv6 to become available ... OK
  ... pre-existing test-cases skipped ...
  Test case: sendmsg4: load prog with wrong expected attach type .. [PASS]
  Test case: sendmsg4: attach prog with wrong attach type .. [PASS]
  Test case: sendmsg4: rewrite IP & port (asm) .. [PASS]
  Test case: sendmsg4: rewrite IP & port (C) .. [PASS]
  Test case: sendmsg4: deny call .. [PASS]
  Test case: sendmsg6: load prog with wrong expected attach type .. [PASS]
  Test case: sendmsg6: attach prog with wrong attach type .. [PASS]
  Test case: sendmsg6: rewrite IP & port (asm) .. [PASS]
  Test case: sendmsg6: rewrite IP & port (C) .. [PASS]
  Test case: sendmsg6: IPv4-mapped IPv6 .. [PASS]
  Test case: sendmsg6: deny call .. [PASS]
  Summary: 27 PASSED, 0 FAILED

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:05 +02:00
Andrey Ignatov
9be71aa6e5 selftests/bpf: Prepare test_sock_addr for extension
test_sock_addr was not easy to extend since it was focused on sys_bind
and sys_connect quite a bit.

Reorganized it so that it'll be easier to cover new test-cases for
`BPF_PROG_TYPE_CGROUP_SOCK_ADDR`:

- decouple test-cases so that only one BPF prog is tested at a time;

- check programmatically that local IP:port for sys_bind, source IP and
  destination IP:port for sys_connect are rewritten property by tested
  BPF programs.

The output of new version:
  # test_sock_addr.sh 2>/dev/null
  Wait for testing IPv4/IPv6 to become available ... OK
  Test case: bind4: load prog with wrong expected attach type .. [PASS]
  Test case: bind4: attach prog with wrong attach type .. [PASS]
  Test case: bind4: rewrite IP & TCP port in .. [PASS]
  Test case: bind4: rewrite IP & UDP port in .. [PASS]
  Test case: bind6: load prog with wrong expected attach type .. [PASS]
  Test case: bind6: attach prog with wrong attach type .. [PASS]
  Test case: bind6: rewrite IP & TCP port in .. [PASS]
  Test case: bind6: rewrite IP & UDP port in .. [PASS]
  Test case: connect4: load prog with wrong expected attach type .. [PASS]
  Test case: connect4: attach prog with wrong attach type .. [PASS]
  Test case: connect4: rewrite IP & TCP port .. [PASS]
  Test case: connect4: rewrite IP & UDP port .. [PASS]
  Test case: connect6: load prog with wrong expected attach type .. [PASS]
  Test case: connect6: attach prog with wrong attach type .. [PASS]
  Test case: connect6: rewrite IP & TCP port .. [PASS]
  Test case: connect6: rewrite IP & UDP port .. [PASS]
  Summary: 16 PASSED, 0 FAILED

(stderr contains errors from libbpf when testing load/attach with
invalid arguments)

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:04 +02:00
Andrey Ignatov
72481f398c libbpf: Support guessing sendmsg{4,6} progs
libbpf can guess prog type and expected attach type based on section
name. Add hints for "cgroup/sendmsg4" and "cgroup/sendmsg6" section
names.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:03 +02:00
Andrey Ignatov
3024cf8248 bpf: Sync bpf.h to tools/
Sync new `BPF_CGROUP_UDP4_SENDMSG` and `BPF_CGROUP_UDP6_SENDMSG`
attach types to tools/.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:02 +02:00
Andrey Ignatov
1cedee13d2 bpf: Hooks for sys_sendmsg
In addition to already existing BPF hooks for sys_bind and sys_connect,
the patch provides new hooks for sys_sendmsg.

It leverages existing BPF program type `BPF_PROG_TYPE_CGROUP_SOCK_ADDR`
that provides access to socket itlself (properties like family, type,
protocol) and user-passed `struct sockaddr *` so that BPF program can
override destination IP and port for system calls such as sendto(2) or
sendmsg(2) and/or assign source IP to the socket.

The hooks are implemented as two new attach types:
`BPF_CGROUP_UDP4_SENDMSG` and `BPF_CGROUP_UDP6_SENDMSG` for UDPv4 and
UDPv6 correspondingly.

UDPv4 and UDPv6 separate attach types for same reason as sys_bind and
sys_connect hooks, i.e. to prevent reading from / writing to e.g.
user_ip6 fields when user passes sockaddr_in since it'd be out-of-bound.

The difference with already existing hooks is sys_sendmsg are
implemented only for unconnected UDP.

For TCP it doesn't make sense to change user-provided `struct sockaddr *`
at sendto(2)/sendmsg(2) time since socket either was already connected
and has source/destination set or wasn't connected and call to
sendto(2)/sendmsg(2) would lead to ENOTCONN anyway.

Connected UDP is already handled by sys_connect hooks that can override
source/destination at connect time and use fast-path later, i.e. these
hooks don't affect UDP fast-path.

Rewriting source IP is implemented differently than that in sys_connect
hooks. When sys_sendmsg is used with unconnected UDP it doesn't work to
just bind socket to desired local IP address since source IP can be set
on per-packet basis by using ancillary data (cmsg(3)). So no matter if
socket is bound or not, source IP has to be rewritten on every call to
sys_sendmsg.

To do so two new fields are added to UAPI `struct bpf_sock_addr`;
* `msg_src_ip4` to set source IPv4 for UDPv4;
* `msg_src_ip6` to set source IPv6 for UDPv6.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:02 +02:00
Andrey Ignatov
13193b0f39 bpf: Define cgroup_bpf_enabled for CONFIG_CGROUP_BPF=n
Static key is used to enable/disable cgroup-bpf related code paths at
run time.

Though it's not defined when cgroup-bpf is disabled at compile time,
i.e. CONFIG_CGROUP_BPF=n, and if some code wants to use it, it has to do
this:

	#ifdef CONFIG_CGROUP_BPF
		if (cgroup_bpf_enabled) {
			/* ... some work ... */
		}
	#endif

This code can be simplified by setting cgroup_bpf_enabled to 0 for
CONFIG_CGROUP_BPF=n case:

	if (cgroup_bpf_enabled) {
		/* ... some work ... */
	}

And it aligns well with existing BPF_CGROUP_RUN_PROG_* macros that
defined for both states of CONFIG_CGROUP_BPF.

Signed-off-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:01 +02:00
Mathieu Xhonneux
3b296633ae selftests/bpf: missing headers test_lwt_seg6local
Previous patch "selftests/bpf: test for seg6local End.BPF action" lacks
some UAPI headers in tools/.

clang -I. -I./include/uapi -I../../../include/uapi -idirafter
/usr/local/include -idirafter
/data/users/yhs/work/llvm/build/install/lib/clang/7.0.0/include
-idirafter /usr/include -Wno-compare-distinct-pointer-types \
         -O2 -target bpf -emit-llvm -c test_lwt_seg6local.c -o - |      \
llc -march=bpf -mcpu=generic  -filetype=obj -o
[...]/net-next/tools/testing/selftests/bpf/test_lwt_seg6local.o
test_lwt_seg6local.c:4:10: fatal error: 'linux/seg6_local.h' file not found
         ^~~~~~~~~~~~~~~~~~~~
1 error generated.
make: Leaving directory
`/data/users/yhs/work/net-next/tools/testing/selftests/bpf'

v2: moving the headers to tools/include/uapi/.

Reported-by: Y Song <ys114321@gmail.com>
Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:41:00 +02:00
Arnd Bergmann
dc3b8ae9d2 bpf: avoid -Wmaybe-uninitialized warning
The stack_map_get_build_id_offset() function is too long for gcc to track
whether 'work' may or may not be initialized at the end of it, leading
to a false-positive warning:

kernel/bpf/stackmap.c: In function 'stack_map_get_build_id_offset':
kernel/bpf/stackmap.c:334:13: error: 'work' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This removes the 'in_nmi_ctx' flag and uses the state of that variable
itself to see if it got initialized.

Fixes: bae77c5eb5 ("bpf: enable stackmap with build_id in nmi context")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:40:59 +02:00
Arnd Bergmann
53c8036cb7 bpf: btf: avoid -Wreturn-type warning
gcc warns about a noreturn function possibly returning in
some configurations:

kernel/bpf/btf.c: In function 'env_type_is_resolve_sink':
kernel/bpf/btf.c:729:1: error: control reaches end of non-void function [-Werror=return-type]

Using BUG() instead of BUG_ON() avoids that warning and otherwise
does the exact same thing.

Fixes: eb3f595dab ("bpf: btf: Validate type reference")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-28 17:40:58 +02:00
Takashi Iwai
011ae2bf06 ALSA: usb-audio: Avoid lowlevel device object
Simplify the device management by replacing the lowlevel device object
allocation with the card->private_data.  Nowadays there is almost no
advantage by the lowlevel device, and with card->private_data, the
code becomes cleaner.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
2018-05-28 14:57:30 +02:00