linux.git/kernel/bpf/devmap.c, branch v4.16.13

bpf: add helper for copying attrs to struct bpf_map

2018-01-14T22:36:29+00:00

All map types reimplement the field-by-field copy of union bpf_attr
members into struct bpf_map.  Add a helper to perform this operation.

Signed-off-by: Jakub Kicinski 
Reviewed-by: Quentin Monnet 
Acked-by: Alexei Starovoitov 
Signed-off-by: Daniel Borkmann

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-10-22T12:39:14+00:00

There were quite a few overlapping sets of changes here.

Daniel's bug fix for off-by-ones in the new BPF branch instructions,
along with the added allowances for "data_end > ptr + x" forms
collided with the metadata additions.

Along with those three changes came veritifer test cases, which in
their final form I tried to group together properly.  If I had just
trimmed GIT's conflict tags as-is, this would have split up the
meta tests unnecessarily.

In the socketmap code, a set of preemption disabling changes
overlapped with the rename of bpf_compute_data_end() to
bpf_compute_data_pointers().

Changes were made to the mv88e6060.c driver set addr method
which got removed in net-next.

The hyperv transport socket layer had a locking change in 'net'
which overlapped with a change of socket state macro usage
in 'net-next'.

Signed-off-by: David S. Miller

bpf: devmap fix arithmetic overflow in bitmap_size calculation

2017-10-21T23:54:09+00:00

An integer overflow is possible in dev_map_bitmap_size() when
calculating the BITS_TO_LONG logic which becomes, after macro
replacement,

	(((n) + (d) - 1)/ (d))

where 'n' is a __u32 and 'd' is (8 * sizeof(long)). To avoid
overflow cast to u64 before arithmetic.

Reported-by: Richard Weinberger 
Acked-by: Daniel Borkmann 
Signed-off-by: John Fastabend 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: Add file mode configuration into bpf maps

2017-10-20T12:32:59+00:00

Introduce the map read/write flags to the eBPF syscalls that returns the
map fd. The flags is used to set up the file mode when construct a new
file descriptor for bpf maps. To not break the backward capability, the
f_flags is set to O_RDWR if the flag passed by syscall is 0. Otherwise
it should be O_RDONLY or O_WRONLY. When the userspace want to modify or
read the map content, it will check the file mode to see if it is
allowed to make the change.

Signed-off-by: Chenbo Feng 
Acked-by: Alexei Starovoitov 
Acked-by: Daniel Borkmann 
Signed-off-by: David S. Miller

bpf: require CAP_NET_ADMIN when using devmap

2017-10-20T12:01:29+00:00

Devmap is used with XDP which requires CAP_NET_ADMIN so lets also
make CAP_NET_ADMIN required to use the map.

Signed-off-by: John Fastabend 
Acked-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: fix splat for illegal devmap percpu allocation

2017-10-19T12:13:50+00:00

It was reported that syzkaller was able to trigger a splat on
devmap percpu allocation due to illegal/unsupported allocation
request size passed to __alloc_percpu():

  [   70.094249] illegal size (32776) or align (8) for percpu allocation
  [   70.094256] ------------[ cut here ]------------
  [   70.094259] WARNING: CPU: 3 PID: 3451 at mm/percpu.c:1365 pcpu_alloc+0x96/0x630
  [...]
  [   70.094325] Call Trace:
  [   70.094328]  __alloc_percpu_gfp+0x12/0x20
  [   70.094330]  dev_map_alloc+0x134/0x1e0
  [   70.094331]  SyS_bpf+0x9bc/0x1610
  [   70.094333]  ? selinux_task_setrlimit+0x5a/0x60
  [   70.094334]  ? security_task_setrlimit+0x43/0x60
  [   70.094336]  entry_SYSCALL_64_fastpath+0x1a/0xa5

This was due to too large max_entries for the map such that we
surpassed the upper limit of PCPU_MIN_UNIT_SIZE. It's fine to
fail naturally here, so switch to __alloc_percpu_gfp() and pass
__GFP_NOWARN instead.

Fixes: 11393cc9b9be ("xdp: Add batching support to redirect map")
Reported-by: Mark Rutland 
Reported-by: Shankara Pailoor 
Reported-by: Richard Weinberger 
Signed-off-by: Daniel Borkmann 
Cc: John Fastabend 
Acked-by: Alexei Starovoitov 
Acked-by: John Fastabend 
Signed-off-by: David S. Miller

bpf: devmap: pass on return value of bpf_map_precharge_memlock

2017-09-18T23:53:30+00:00

If bpf_map_precharge_memlock in dev_map_alloc, -ENOMEM is returned
regardless of the actual error produced by bpf_map_precharge_memlock.
Fix it by passing on the error returned by bpf_map_precharge_memlock.

Also return -EINVAL instead of -ENOMEM if the page count overflow check
fails.

This makes dev_map_alloc match the behavior of other bpf maps' alloc
functions wrt. return values.

Signed-off-by: Tobias Klauser 
Acked-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: devmap, use cond_resched instead of cpu_relax

2017-09-09T04:11:00+00:00

Be a bit more friendly about waiting for flush bits to complete.
Replace the cpu_relax() with a cond_resched().

Suggested-by: Daniel Borkmann 
Acked-by: Daniel Borkmann 
Signed-off-by: John Fastabend 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller

bpf: netdev is never null in __dev_map_flush

2017-08-24T05:43:40+00:00

No need to test for it in fast-path, every dev in bpf_dtab_netdev
is guaranteed to be non-NULL, otherwise dev_map_update_elem() will
fail in the first place.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Acked-by: John Fastabend 
Signed-off-by: David S. Miller

bpf: minor cleanups for dev_map

2017-08-23T04:26:29+00:00

Some minor code cleanups, while going over it I also noticed that
we're accounting the bitmap only for one CPU currently, so fix that
up as well.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: David S. Miller