[PATCH 4.9 25/59] bpf: change back to orig prog on too many passes

[Greg Kroah-Hartman]

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

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

From: Daniel Borkmann <daniel@xxxxxxxxxxxxx>


[ Upstream commit 9d5ecb09d525469abd1a10c096cb5a17206523f2 ]

If after too many passes still no image could be emitted, then
swap back to the original program as we do in all other cases
and don't use the one with blinding.

Fixes: 959a75791603 ("bpf, x86: add support for constant blinding")
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/net/bpf_jit_comp.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -1172,6 +1172,8 @@ struct bpf_prog *bpf_int_jit_compile(str
 		set_memory_ro((unsigned long)header, header->pages);
 		prog->bpf_func = (void *)image;
 		prog->jited = 1;
+	} else {
+		prog = orig_prog;
 	}
 
 out_addrs: