Commit 0472301a authored Jun 28, 2019 by Baruch Siach Committed by Daniel Borkmann Jun 29, 2019

bpf: fix uapi bpf_prog_info fields alignment

Merge commit 1c8c5a9d ("Merge
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next"

) undid the
fix from commit 36f9814a ("bpf: fix uapi hole for 32 bit compat
applications") by taking the gpl_compatible 1-bit field definition from
commit b85fab0e ("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.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

parent 75672dda

include/uapi/linux/bpf.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -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;

tools/include/uapi/linux/bpf.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -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;

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