When BPF programs which consists of multiple executable sections via
iproute2+libbpf (configured with LIBBPF_FORCE=on), we noticed that a
wrong section can be attached to a device. E.g.:
# tc qdisc replace dev lxc_health clsact
# tc filter replace dev lxc_health ingress prio 1 \
handle 1 bpf da obj bpf_lxc.o sec from-container
# tc filter show dev lxc_health ingress filter protocol all
pref 1 bpf chain 0 filter protocol all pref 1 bpf chain 0
handle 0x1 bpf_lxc.o:[__send_drop_notify] <-- WRONG SECTION
direct-action not_in_hw id 38 tag 7d891814eda6809e jited
After taking a closer look into load_bpf_object() in lib/bpf_libbpf.c,
we noticed that the filter used in the program iterator does not check
whether a program section name matches a requested section name
(cfg->section). This can lead to a wrong prog FD being used to attach
the program.
Fixes: 6d61a2b557 ("lib: add libbpf support")
Signed-off-by: Martynas Pumputis <m@lambda.lt>
Acked-by: Hangbin Liu <haliu@redhat.com>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
83d4d61bc9