Commit Graph

13 Commits

Author SHA1 Message Date
Daniel Borkmann 0631b6583f bpf, mips: remove unused function
The ool_skb_header_pointer() and size_to_len() is unused same as
tmp_offset, therefore remove all of them.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-14 19:11:45 -07:00
Daniel Borkmann 4db25cc988 bpf, mips64: remove ld_abs/ld_ind
Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from mips64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 16:49:20 -07:00
Daniel Borkmann e472d5d8af bpf, mips64: remove unneeded zero check from div/mod with k
The verifier in both cBPF and eBPF reject div/mod by 0 imm,
so this can never load. Remove emitting such test and reject
it from being JITed instead (the latter is actually also not
needed, but given practice in sparc64, ppc64 today, so
doesn't hurt to add it here either).

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Daney <david.daney@cavium.com>
Reviewed-by: David Daney <david.daney@cavium.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-26 16:42:06 -08:00
Daniel Borkmann 1fb5c9c622 bpf, mips64: remove obsolete exception handling from div/mod
Since we've changed div/mod exception handling for src_reg in
eBPF verifier itself, remove the leftovers from mips64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Daney <david.daney@cavium.com>
Reviewed-by: David Daney <david.daney@cavium.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-26 16:42:06 -08:00
Daniel Borkmann fa9dd599b4 bpf: get rid of pure_initcall dependency to enable jits
Having a pure_initcall() callback just to permanently enable BPF
JITs under CONFIG_BPF_JIT_ALWAYS_ON is unnecessary and could leave
a small race window in future where JIT is still disabled on boot.
Since we know about the setting at compilation time anyway, just
initialize it properly there. Also consolidate all the individual
bpf_jit_enable variables into a single one and move them under one
location. Moreover, don't allow for setting unspecified garbage
values on them.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-19 18:37:00 -08:00
Alexei Starovoitov 60b58afc96 bpf: fix net.core.bpf_jit_enable race
global bpf_jit_enable variable is tested multiple times in JITs,
blinding and verifier core. The malicious root can try to toggle
it while loading the programs. This race condition was accounted
for and there should be no issues, but it's safer to avoid
this race condition.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2017-12-17 20:34:36 +01:00
Wei Yongjun 6a2932a463 MIPS: bpf: Fix a typo in build_one_insn()
Fix a typo in build_one_insn().

Fixes: b6bd53f9c4 ("MIPS: Add missing file for eBPF JIT.")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Cc: <stable@vger.kernel.org> # 4.13+
Patchwork: https://patchwork.linux-mips.org/patch/17491/
Signed-off-by: James Hogan <jhogan@kernel.org>
2017-11-01 00:09:17 +00:00
Matt Redfearn 94c3390ab8 MIPS: bpf: Fix uninitialised target compiler error
Compiling ebpf_jit.c with gcc 4.9 results in a (likely spurious)
compiler warning, as gcc has detected that the variable "target" may be
used uninitialised. Since -Werror is active, this is treated as an error
and causes a kernel build failure whenever CONFIG_MIPS_EBPF_JIT is
enabled.

arch/mips/net/ebpf_jit.c: In function 'build_one_insn':
arch/mips/net/ebpf_jit.c:1118:80: error: 'target' may be used
uninitialized in this function [-Werror=maybe-uninitialized]
    emit_instr(ctx, j, target);
                                                                                ^
cc1: all warnings being treated as errors

Fix this by initialising "target" to 0. If it really is used
uninitialised this would result in a jump to 0 and a detectable run time
failure.

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Fixes: b6bd53f9c4 ("MIPS: Add missing file for eBPF JIT.")
Cc: James Hogan <james.hogan@imgtec.com>
Cc: David Daney <david.daney@cavium.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # v4.13+
Patchwork: https://patchwork.linux-mips.org/patch/17375/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2017-10-09 14:53:38 +02:00
Colin Ian King 4a00aa0577 MIPS,bpf: fix missing break in switch statement
There is a missing break causing a fall-through and setting
ctx.use_bbit_insns to the wrong value. Fix this by adding the
missing break.

Detected with cppcheck:
"Variable 'ctx.use_bbit_insns' is reassigned a value before the old
one has been used. 'break;' missing?"

Fixes: 8d8d18c328 ("MIPS,bpf: Fix using smp_processor_id() in preemptible splat.")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 16:18:00 -07:00
David Daney 6035b3faf3 MIPS,bpf: Cache value of BPF_OP(insn->code) in eBPF JIT.
The code looks a little cleaner if we replace BPF_OP(insn->code) with
the local variable bpf_op.  Caching the value this way also saves 300
bytes (about 1%) in the code size of the JIT.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-21 10:31:34 -07:00
David Daney a67b375fdc MIPS, bpf: Implement JLT, JLE, JSLT and JSLE ops in the eBPF JIT.
Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-21 10:31:34 -07:00
David Daney 8d8d18c328 MIPS,bpf: Fix using smp_processor_id() in preemptible splat.
If the kernel is configured with preemption enabled we were getting
warning stack traces for use of current_cpu_type().

Fix by moving the test between preempt_disable()/preempt_enable() and
caching the results of the CPU type tests for use during code
generation.

Signed-off-by: David Daney <david.daney@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-21 10:31:34 -07:00
David Daney b6bd53f9c4 MIPS: Add missing file for eBPF JIT.
Inexplicably, commit f381bf6d82 ("MIPS: Add support for eBPF JIT.")
lost a file somewhere on its path to Linus' tree.  Add back the
missing ebpf_jit.c so that we can build with CONFIG_BPF_JIT selected.

This version of ebpf_jit.c is identical to the original except for two
minor change need to resolve conflicts with changes merged from the
BPF branch:

A) Set prog->jited_len = image_size;
B) Use BPF_TAIL_CALL instead of BPF_CALL | BPF_X

Fixes: f381bf6d82 ("MIPS: Add support for eBPF JIT.")
Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-04 11:23:58 -07:00