Merge branch 'bpf-jit-fixes'

Daniel Borkmann says:

====================
Two fixes that deal with buggy usage of bpf_helper_changes_pkt_data()
in the sense that they also reload cached skb data when there's no
skb context but xdp one, for example. A fix where skb meta data is
reloaded out of the wrong register on helper call, rest is test cases
and making sure on verifier side that there's always the guarantee
that ctx sits in r1. Thanks!
====================

Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d4593571c404..e39b01317b6f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1674,7 +1674,13 @@ static int check_call(struct bpf_verifier_env *env, int func_id, int insn_idx)
 		return -EINVAL;
 	}
 
+	/* With LD_ABS/IND some JITs save/restore skb from r1. */
 	changes_data = bpf_helper_changes_pkt_data(fn->func);
+	if (changes_data && fn->arg1_type != ARG_PTR_TO_CTX) {
+		verbose(env, "kernel subsystem misconfigured func %s#%d: r1 != ctx\n",
+			func_id_name(func_id), func_id);
+		return -EINVAL;
+	}
 
 	memset(&meta, 0, sizeof(meta));
 	meta.pkt_access = fn->pkt_access;