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. Embed gpl_compatible into an anonymous union with 32-bit pad
member 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>
---
v2:
Use anonymous union with pad to make it less likely to break again in
the future.
---
include/uapi/linux/bpf.h | 5 ++++-
tools/include/uapi/linux/bpf.h | 5 ++++-
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index a8b823c30b43..766eae02d7ae 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -3142,7 +3142,10 @@ struct bpf_prog_info {
__aligned_u64 map_ids;
char name[BPF_OBJ_NAME_LEN];
__u32 ifindex;
- __u32 gpl_compatible:1;
+ union {
+ __u32 gpl_compatible:1;
+ __u32 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..766eae02d7ae 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -3142,7 +3142,10 @@ struct bpf_prog_info {
__aligned_u64 map_ids;
char name[BPF_OBJ_NAME_LEN];
__u32 ifindex;
- __u32 gpl_compatible:1;
+ union {
+ __u32 gpl_compatible:1;
+ __u32 pad;
+ };
__u64 netns_dev;
__u64 netns_ino;
__u32 nr_jited_ksyms;
--
2.20.1
