[PATCH 5.14 137/151] powerpc/bpf ppc32: Do not emit zero extend instruction for 64-bit BPF_END

Greg Kroah-Hartman
2021-10-11T14:12:40Z

From: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>

[ Upstream commit 48164fccdff6d5cc11308126c050bd25a329df25 ]

Suppress emitting zero extend instruction for 64-bit BPF_END_FROM_[L|B]E
operation.

Fixes: 51c66ad849a703 ("powerpc/bpf: Implement extended BPF on PPC32")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b4e3c3546121315a8e2059b19a1bda84971816e4.1633464148.git.naveen.n.rao@linux.vnet.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/net/bpf_jit_comp32.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c
index ae3a31cb7b7e..c48de048c8ce 100644
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -1103,7 +1103,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
return -EOPNOTSUPP;
}
if (BPF_CLASS(code) == BPF_ALU && !fp->aux->verifier_zext &&
- !insn_is_zext(&insn[i + 1]))
+ !insn_is_zext(&insn[i + 1]) && !(BPF_OP(code) == BPF_END && imm == 64))
EMIT(PPC_RAW_LI(dst_reg_h, 0));
}

--
2.33.0