[PATCH] bpf: Fix build in minimal configurations, again

Arnd Bergmann
2019-12-10T20:36:18Z

Building with -Werror showed another failure:

kernel/bpf/btf.c: In function 'btf_get_prog_ctx_type.isra.31':
kernel/bpf/btf.c:3508:63: error: array subscript 0 is above array bounds of 'u8[0]' {aka 'unsigned char[0]'} [-Werror=array-bounds]
ctx_type = btf_type_member(conv_struct) + bpf_ctx_convert_map[prog_type] * 2;

I don't actually understand why the array is empty, but a similar
fix has addressed a related problem, so I suppose we can do the
same thing here.

Fixes: ce27709b8162 ("bpf: Fix build in minimal configurations")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
kernel/bpf/btf.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c
index 7d40da240891..ed2075884724 100644
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -3470,6 +3470,7 @@ static u8 bpf_ctx_convert_map[] = {
[_id] = __ctx_convert##_id,
#include <linux/bpf_types.h>
#undef BPF_PROG_TYPE
+ 0, /* avoid empty array */
};
#undef BPF_MAP_TYPE

--
2.20.0