From: Joanne Koong Date: Wed, 1 Mar 2023 15:49:44 +0000 (-0800) Subject: bpf: Support "sk_buff" and "xdp_buff" as valid kfunc arg types X-Git-Tag: v6.6.17~4755^2~413^2~31^2~9 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2f46439346700a2b41cf0fa9432f110f42fd8821;p=platform%2Fkernel%2Flinux-rpi.git bpf: Support "sk_buff" and "xdp_buff" as valid kfunc arg types 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 Link: https://lore.kernel.org/r/20230301154953.641654-2-joannelkoong@gmail.com Signed-off-by: Alexei Starovoitov --- diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index fa22ec7..84cca84 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -5683,6 +5683,10 @@ again: * int socket_filter_bpf_prog(struct __sk_buff *skb) * { // no fields of skb are ever used } */ + 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; if (strcmp(ctx_tname, tname)) { /* bpf_user_pt_regs_t is a typedef, so resolve it to * underlying struct and check name again