diff options
| author | Daniel Borkmann <daniel@iogearbox.net> | 2017-04-24 22:14:35 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-04-24 16:18:10 -0400 |
| commit | e390b55d5aefe2b51569068b2a505d19d72afbf1 (patch) | |
| tree | a3f9dcb6e95ede17e39fa54bcc37f23044d95f72 | |
| parent | 91ec701a553cb3de470fd471c6fefe3ad1125455 (diff) | |
| download | linux-e390b55d5aefe2b51569068b2a505d19d72afbf1.tar.bz2 | |
bpf: make bpf_xdp_adjust_head support mandatory
Now that also the last in-tree user of the xdp_adjust_head bit has
been removed, we can remove the flag from struct bpf_prog altogether.
This, at the same time, also makes sure that any future driver for
XDP comes with bpf_xdp_adjust_head() support right away.
A rejection based on this flag would also mean that tail calls
couldn't be used with such driver as per c2002f983767 ("bpf: fix
checking xdp_adjust_head on tail calls") fix, thus lets not allow
for it in the first place.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/filter.h | 3 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 3 |
2 files changed, 1 insertions, 5 deletions
diff --git a/include/linux/filter.h b/include/linux/filter.h index 511fe910bf1d..9a7786db14fa 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -413,8 +413,7 @@ struct bpf_prog { locked:1, /* Program image locked? */ gpl_compatible:1, /* Is filter GPL compatible? */ cb_access:1, /* Is control block accessed? */ - dst_needed:1, /* Do we need dst entry? */ - xdp_adjust_head:1; /* Adjusting pkt head? */ + dst_needed:1; /* Do we need dst entry? */ kmemcheck_bitfield_end(meta); enum bpf_prog_type type; /* Type of BPF program */ u32 len; /* Number of filter blocks */ diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index ca15cf2b85bb..6f8b6ed690be 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3346,8 +3346,6 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) prog->dst_needed = 1; if (insn->imm == BPF_FUNC_get_prandom_u32) bpf_user_rnd_init_once(); - if (insn->imm == BPF_FUNC_xdp_adjust_head) - prog->xdp_adjust_head = 1; if (insn->imm == BPF_FUNC_tail_call) { /* If we tail call into other programs, we * cannot make any assumptions since they can @@ -3355,7 +3353,6 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) * the program array. */ prog->cb_access = 1; - prog->xdp_adjust_head = 1; /* mark bpf_tail_call as different opcode to avoid * conditional branch in the interpeter for every normal |