On 12/18/2017 07:09 PM, Alexei Starovoitov wrote:
> From: Alexei Starovoitov <a...@fb.com>
>
> fix the following issue:
> arch/arm64/net/bpf_jit_comp.c: In function 'bpf_int_jit_compile':
> arch/arm64/net/bpf_jit_comp.c:982:18: error: 'image_size' may be used
> uninitialized in this function [-Werror=maybe-uninitialized]
>
> Fixes: db496944fdaa ("bpf: arm64: add JIT support for multi-function
> programs")
> Reported-by: Arnd Bergmann <a...@arndb.de>
> Signed-off-by: Alexei Starovoitov <a...@kernel.org>
> ---
> arch/arm64/net/bpf_jit_comp.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
> index 396490cf7316..acaa935ed977 100644
> --- a/arch/arm64/net/bpf_jit_comp.c
> +++ b/arch/arm64/net/bpf_jit_comp.c
> @@ -897,6 +897,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog
> *prog)
> image_ptr = jit_data->image;
> header = jit_data->header;
> extra_pass = true;
> + image_size = sizeof(u32) * ctx.idx;
> goto skip_init_ctx;
> }
> memset(&ctx, 0, sizeof(ctx));
>
I don't really mind, but it feels more complex than it needs to be
imho, since in the initial pass you fetch 'image_size' in fake pass
from ctx.idx, then we set ctx.idx to 0 again, do another pass and
use the cached ctx.idx from that second pass instead of the first
one where we set 'image_size' originally, so we definitely need to
take that into consideration in future reviews at least.
Thanks,
Daniel
