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| author | Song Liu <song@kernel.org> | 2022-09-26 11:47:38 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2022-09-26 20:40:43 -0700 |
| commit | 19c02415da2345d0dda2b5c4495bc17cc14b18b5 (patch) | |
| tree | 64cebe945349bf772b0d4cdb212ee1fc55d38215 /arch/x86/net | |
| parent | 30b8fdbbe31b2422f46fcd6d3960e563affe76d7 (diff) | |
| download | linux-19c02415da2345d0dda2b5c4495bc17cc14b18b5.tar.bz2 | |
bpf: use bpf_prog_pack for bpf_dispatcher
Allocate bpf_dispatcher with bpf_prog_pack_alloc so that bpf_dispatcher
can share pages with bpf programs.
arch_prepare_bpf_dispatcher() is updated to provide a RW buffer as working
area for arch code to write to.
This also fixes CPA W^X warnning like:
CPA refuse W^X violation: 8000000000000163 -> 0000000000000163 range: ...
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20220926184739.3512547-2-song@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'arch/x86/net')
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index d4a6183197e9..35796db58116 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -2242,7 +2242,7 @@ cleanup: return ret; } -static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) +static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs, u8 *image, u8 *buf) { u8 *jg_reloc, *prog = *pprog; int pivot, err, jg_bytes = 1; @@ -2258,12 +2258,12 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3), progs[a]); err = emit_cond_near_jump(&prog, /* je func */ - (void *)progs[a], prog, + (void *)progs[a], image + (prog - buf), X86_JE); if (err) return err; - emit_indirect_jump(&prog, 2 /* rdx */, prog); + emit_indirect_jump(&prog, 2 /* rdx */, image + (prog - buf)); *pprog = prog; return 0; @@ -2288,7 +2288,7 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) jg_reloc = prog; err = emit_bpf_dispatcher(&prog, a, a + pivot, /* emit lower_part */ - progs); + progs, image, buf); if (err) return err; @@ -2302,7 +2302,7 @@ static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs) emit_code(jg_reloc - jg_bytes, jg_offset, jg_bytes); err = emit_bpf_dispatcher(&prog, a + pivot + 1, /* emit upper_part */ - b, progs); + b, progs, image, buf); if (err) return err; @@ -2322,12 +2322,12 @@ static int cmp_ips(const void *a, const void *b) return 0; } -int arch_prepare_bpf_dispatcher(void *image, s64 *funcs, int num_funcs) +int arch_prepare_bpf_dispatcher(void *image, void *buf, s64 *funcs, int num_funcs) { - u8 *prog = image; + u8 *prog = buf; sort(funcs, num_funcs, sizeof(funcs[0]), cmp_ips, NULL); - return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs); + return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs, image, buf); } struct x64_jit_data { |