s390/bpf: Fix JMP_JGE_X (A > X) and JMP_JGT_X (A >= X)

Currently the signed COMPARE (cr) instruction is used to compare "A"
with "X". This is not correct because "A" and "X" are both unsigned.
To fix this use the unsigned COMPARE LOGICAL (clr) instruction instead.

Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 8bc474fb52fd086348ba0fccb3b73f50a1793348..524496d47ef506d0ca888356df21fd4bb7e25053 100644 (file)
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -502,8 +502,8 @@ branch:             if (filter->jt == filter->jf) {
 xbranch:       /* Emit compare if the branch targets are different */
                if (filter->jt != filter->jf) {
                        jit->seen |= SEEN_XREG;
-                       /* cr %r5,%r12 */
-                       EMIT2(0x195c);
+                       /* clr %r5,%r12 */
+                       EMIT2(0x155c);
                }
                goto branch;
        case BPF_JMP | BPF_JSET | BPF_X: /* ip += (A & X) ? jt : jf */