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

From: Jakub Kicinski
Date: Tue Dec 10 2019 - 15:55:02 EST

On Tue, 10 Dec 2019 19:14:12 +0100, Toke HÃiland-JÃrgensen 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.
> Signed-off-by: Toke HÃiland-JÃrgensen <toke@xxxxxxxxxx>

Fixes: 71bb428fe2c1 ("tools: bpf: add bpftool")


Fixes: f84192ee00b7 ("tools: bpftool: resolve calls without using imm field")