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. Add 31-bit pad after gpl_compatible to restore alignment of following fields. Thanks to Dmitry V. Levin his analysis of this bug history. Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Baruch Siach <baruch@xxxxxxxxxx> --- v3: Use alignment pad as Alexei Starovoitov suggested v2: Use anonymous union with pad to make it less likely to break again in the future. --- include/uapi/linux/bpf.h | 1 + tools/include/uapi/linux/bpf.h | 1 + 2 files changed, 2 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index a8b823c30b43..29a5bc3d5c66 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -3143,6 +3143,7 @@ struct bpf_prog_info { char name[BPF_OBJ_NAME_LEN]; __u32 ifindex; __u32 gpl_compatible:1; + __u32 :31; /* alignment pad */ __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 a8b823c30b43..29a5bc3d5c66 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3143,6 +3143,7 @@ struct bpf_prog_info { char name[BPF_OBJ_NAME_LEN]; __u32 ifindex; __u32 gpl_compatible:1; + __u32 :31; /* alignment pad */ __u64 netns_dev; __u64 netns_ino; __u32 nr_jited_ksyms; -- 2.20.1