Re: [PATCH] bpf: Prevent double bpf_prog_put call from bpf_tracing_prog_attach
From: Toke Høiland-Jørgensen <hidden>
Date: 2021-01-11 20:05:05
Also in:
bpf
Jiri Olsa [off-list ref] writes:
The bpf_tracing_prog_attach error path calls bpf_prog_put
on prog, which causes refcount underflow when it's called
from link_create function.
link_create
prog = bpf_prog_get <-- get
...
tracing_bpf_link_attach(prog..
bpf_tracing_prog_attach(prog..
out_put_prog:
bpf_prog_put(prog); <-- put
if (ret < 0)
bpf_prog_put(prog); <-- put
Removing bpf_prog_put call from bpf_tracing_prog_attach
and making sure its callers call it instead.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>Acked-by: Toke Høiland-Jørgensen <redacted>