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

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

From: Alexei Starovoitov <a...@plumgrid.com>

commit fdfaf64e75397567257e1051931f9a3377360665 upstream.

Commit a998d4342337 claimed to introduce negative offset support to x86 jit,
but it couldn't be working, since at the time of the execution
of LD+ABS or LD+IND instructions via call into
bpf_internal_load_pointer_neg_helper() the %edx (3rd argument of this func)
had junk value instead of access size in bytes (1 or 2 or 4).

Store size into %edx instead of %ecx (what original commit intended to do)

Fixes: a998d4342337 ("bpf jit: Let the x86 jit handle negative offsets")
Signed-off-by: Alexei Starovoitov <a...@plumgrid.com>
Cc: Jan Seiffert <kaffeemons...@googlemail.com>
Cc: Eric Dumazet <eduma...@google.com>
Acked-by: Eric Dumazet <eduma...@google.com>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/x86/net/bpf_jit.S |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/net/bpf_jit.S
+++ b/arch/x86/net/bpf_jit.S
@@ -140,7 +140,7 @@ bpf_slow_path_byte_msh:
        push    %r9;                                            \
        push    SKBDATA;                                        \
 /* rsi already has offset */                                   \
-       mov     $SIZE,%ecx;     /* size */                      \
+       mov     $SIZE,%edx;     /* size */                      \
        call    bpf_internal_load_pointer_neg_helper;           \
        test    %rax,%rax;                                      \
        pop     SKBDATA;                                        \


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