netdev - [PATCH v3 bpf 6/9] libbpf: enforce 64-bitness of BTF for BPF object files

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Date:   Thu, 13 Aug 2020 13:49:42 -0700
From:   Andrii Nakryiko <andriin@...com>
To:     <bpf@...r.kernel.org>, <netdev@...r.kernel.org>, <ast@...com>,
        <daniel@...earbox.net>
CC:     <andrii.nakryiko@...il.com>, <kernel-team@...com>,
        Andrii Nakryiko <andriin@...com>
Subject: [PATCH v3 bpf 6/9] libbpf: enforce 64-bitness of BTF for BPF object files

BPF object files are always targeting 64-bit BPF target architecture, so
enforce that at BTF level as well.

Signed-off-by: Andrii Nakryiko <andriin@...com>
---
 tools/lib/bpf/libbpf.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4a8524b2dda1..738579c338a5 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -2434,6 +2434,8 @@ static int bpf_object__init_btf(struct bpf_object *obj,
 				BTF_ELF_SEC, err);
 			goto out;
 		}
+		/* enforce 8-byte pointers for BPF-targeted BTFs */
+		btf__set_pointer_size(obj->btf, 8);
 		err = 0;
 	}
 	if (btf_ext_data) {
@@ -2542,6 +2544,8 @@ static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj)
 		if (IS_ERR(kern_btf))
 			return PTR_ERR(kern_btf);
 
+		/* enforce 8-byte pointers for BPF-targeted BTFs */
+		btf__set_pointer_size(obj->btf, 8);
 		bpf_object__sanitize_btf(obj, kern_btf);
 	}
 
-- 
2.24.1