lkml.org 
[lkml]   [2018]   [Jul]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.17 099/101] bpf: enforce correct alignment for instructions
Date
4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Eric Dumazet <edumazet@google.com>

commit 9262478220eac908ae6e168c3df2c453c87e2da3 upstream.

After commit 9facc336876f ("bpf: reject any prog that failed read-only lock")
offsetof(struct bpf_binary_header, image) became 3 instead of 4,
breaking powerpc BPF badly, since instructions need to be word aligned.

Fixes: 9facc336876f ("bpf: reject any prog that failed read-only lock")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
include/linux/filter.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -455,7 +455,9 @@ struct sock_fprog_kern {
struct bpf_binary_header {
u16 pages;
u16 locked:1;
- u8 image[];
+
+ /* Some arches need word alignment for their instructions */
+ u8 image[] __aligned(4);
};

struct bpf_prog {

\
 
 \ /
  Last update: 2018-07-20 14:49    [W:0.275 / U:0.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site