From: Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com
commit 8bbc9d822421d9ac8ff9ed26a3713c9afc69d6c8 upstream.
Only ignore the operation if dividing by 1.
Fixes: 156d0e290e969c ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF") Signed-off-by: Naveen N. Rao naveen.n.rao@linux.vnet.ibm.com Tested-by: Johan Almbladh johan.almbladh@anyfinetworks.com Reviewed-by: Christophe Leroy christophe.leroy@csgroup.eu Acked-by: Song Liu songliubraving@fb.com Acked-by: Johan Almbladh johan.almbladh@anyfinetworks.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Link: https://lore.kernel.org/r/c674ca18c3046885602caebb326213731c675d06.163346414... Signed-off-by: Thadeu Lima de Souza Cascardo cascardo@canonical.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/powerpc/net/bpf_jit_comp64.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
--- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -415,8 +415,14 @@ static int bpf_jit_build_body(struct bpf case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */ if (imm == 0) return -EINVAL; - else if (imm == 1) - goto bpf_alu32_trunc; + if (imm == 1) { + if (BPF_OP(code) == BPF_DIV) { + goto bpf_alu32_trunc; + } else { + EMIT(PPC_RAW_LI(dst_reg, 0)); + break; + } + }
PPC_LI32(b2p[TMP_REG_1], imm); switch (BPF_CLASS(code)) {