The bpf mirror of the in-kernel sk_buff and xdp_buff data structures are __sk_buff and xdp_md. Currently, when we pass in the program ctx to a kfunc where the program ctx is a skb or xdp buffer, we reject the program if the in-kernel definition is sk_buff/xdp_buff instead of __sk_buff/xdp_md. This change allows "sk_buff <--> __sk_buff" and "xdp_buff <--> xdp_md" to be recognized as valid matches. The user program may pass in their program ctx as a __sk_buff or xdp_md, and the in-kernel definition of the kfunc may define this arg as a sk_buff or xdp_buff. Signed-off-by: Joanne Koong <joannelkoong@xxxxxxxxx> --- kernel/bpf/btf.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index 6582735ef1fc..ae321c358699 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -5675,6 +5675,10 @@ btf_get_prog_ctx_type(struct bpf_verifier_log *log, const struct btf *btf, bpf_log(log, "Please fix kernel include/linux/bpf_types.h\n"); return NULL; } + if (strcmp(ctx_tname, "__sk_buff") == 0 && strcmp(tname, "sk_buff") == 0) + return ctx_type; + if (strcmp(ctx_tname, "xdp_md") == 0 && strcmp(tname, "xdp_buff") == 0) + return ctx_type; /* only compare that prog's ctx type name is the same as * kernel expects. No need to compare field by field. * It's ok for bpf prog to do: -- 2.30.2
