[PATCH 4.17 100/101] bpf, arm32: fix to use bpf_jit_binary_lock_ro api

From: Greg Kroah-Hartman
Date: Fri Jul 20 2018 - 08:45:03 EST


4.17-stable review patch. If anyone has any objections, please let me know.

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

From: Daniel Borkmann <daniel@xxxxxxxxxxxxx>

commit 18d405af30bf6506bf2fc49056de7691c949812e upstream.

Any eBPF JIT that where its underlying arch supports ARCH_HAS_SET_MEMORY
would need to use bpf_jit_binary_{un,}lock_ro() pair instead of the
set_memory_{ro,rw}() pair directly as otherwise changes to the former
might break. arm32's eBPF conversion missed to change it, so fix this
up here.

Fixes: 39c13c204bb1 ("arm: eBPF JIT compiler")
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/arm/net/bpf_jit_32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/arm/net/bpf_jit_32.c
+++ b/arch/arm/net/bpf_jit_32.c
@@ -1928,7 +1928,7 @@ struct bpf_prog *bpf_int_jit_compile(str
/* there are 2 passes here */
bpf_jit_dump(prog->len, image_size, 2, ctx.target);

- set_memory_ro((unsigned long)header, header->pages);
+ bpf_jit_binary_lock_ro(header);
prog->bpf_func = (void *)ctx.target;
prog->jited = 1;
prog->jited_len = image_size;