Message ID | 202003281643.02SGhPH7029961@sdf.org |
---|---|
State | Not Applicable |
Delegated to: | David Miller |
Headers | show |
Series | None | expand |
On Sat, Mar 28, 2020 at 9:46 AM George Spelvin <lkml@sdf.org> wrote: > > Smaller, faster, and a smidge more uniform than %. > > Signed-off-by: George Spelvin <lkml@sdf.org> > Cc: Daniel Borkmann <daniel@iogearbox.net> > Cc: Alexei Starovoitov <ast@kernel.org> > Cc: Martin KaFai Lau <kafai@fb.com> > Cc: Song Liu <songliubraving@fb.com> > Cc: Yonghong Song <yhs@fb.com> > Cc: Andrii Nakryiko <andriin@fb.com> > Cc: bpf@vger.kernel.org > Cc: netdev@vger.kernel.org If Linus is going to pick up the whole set at once: Acked-by: Alexei Starovoitov <ast@kernel.org>
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index af6b738cf435c..61713a7f73d85 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -874,7 +874,7 @@ bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, hdr->pages = pages; hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)), PAGE_SIZE - sizeof(*hdr)); - start = (get_random_int() % hole) & ~(alignment - 1); + start = get_random_max32(hole) & ~(alignment - 1); /* Leave a random number of instructions before BPF code. */ *image_ptr = &hdr->image[start]; @@ -947,7 +947,7 @@ static int bpf_jit_blind_insn(const struct bpf_insn *from, bool emit_zext) { struct bpf_insn *to = to_buff; - u32 imm_rnd = get_random_int(); + u32 imm_rnd = get_random_u32(); s16 off; BUILD_BUG_ON(BPF_REG_AX + 1 != MAX_BPF_JIT_REG);
Smaller, faster, and a smidge more uniform than %. Signed-off-by: George Spelvin <lkml@sdf.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Martin KaFai Lau <kafai@fb.com> Cc: Song Liu <songliubraving@fb.com> Cc: Yonghong Song <yhs@fb.com> Cc: Andrii Nakryiko <andriin@fb.com> Cc: bpf@vger.kernel.org Cc: netdev@vger.kernel.org --- kernel/bpf/core.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)