[PATCH] bpf: fix uapi bpf_prog_info fields alignment

[Baruch Siach]

Merge commit 1c8c5a9d38f60 ("Merge
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next") undid the
fix from commit 36f9814a494 ("bpf: fix uapi hole for 32 bit compat
applications") by taking the gpl_compatible 1-bit field definition from
commit b85fab0e67b162 ("bpf: Add gpl_compatible flag to struct
bpf_prog_info") as is. That breaks architectures with 16-bit alignment
like m68k. Widen gpl_compatible to 32-bit to restore alignment of the
following fields.

Thanks to Dmitry V. Levin his analysis of this bug history.

Cc: Jiri Olsa <jo...@kernel.org>
Cc: Daniel Borkmann <dan...@iogearbox.net>
Cc: Geert Uytterhoeven <ge...@linux-m68k.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Signed-off-by: Baruch Siach <bar...@tkos.co.il>
---
 include/uapi/linux/bpf.h       | 2 +-
 tools/include/uapi/linux/bpf.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 63e0cf66f01a..fe73829b5b1c 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -3140,7 +3140,7 @@ struct bpf_prog_info {
        __aligned_u64 map_ids;
        char name[BPF_OBJ_NAME_LEN];
        __u32 ifindex;
-       __u32 gpl_compatible:1;
+       __u32 gpl_compatible;
        __u64 netns_dev;
        __u64 netns_ino;
        __u32 nr_jited_ksyms;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 63e0cf66f01a..fe73829b5b1c 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -3140,7 +3140,7 @@ struct bpf_prog_info {
        __aligned_u64 map_ids;
        char name[BPF_OBJ_NAME_LEN];
        __u32 ifindex;
-       __u32 gpl_compatible:1;
+       __u32 gpl_compatible;
        __u64 netns_dev;
        __u64 netns_ino;
        __u32 nr_jited_ksyms;
-- 
2.20.1