Re: [PATCH bpf v2] bpftool: Don't crash on missing jited insns or ksyms

From: Martin Lau
Date: Tue Dec 10 2019 - 13:22:05 EST


On Tue, Dec 10, 2019 at 07:14:12PM +0100, Toke Høiland-Jørgensen wrote:
> When the kptr_restrict sysctl is set, the kernel can fail to return
> jited_ksyms or jited_prog_insns, but still have positive values in
> nr_jited_ksyms and jited_prog_len. This causes bpftool to crash when trying
> to dump the program because it only checks the len fields not the actual
> pointers to the instructions and ksyms.
>
> Fix this by adding the missing checks.
Acked-by: Martin KaFai Lau <kafai@xxxxxx>