diff mbox series

[5/9] powerpc/bpf: Fix BPF_MOD when imm == 1

Message ID 8cb6a1725cf3c38ca90ed7f195f78a5b5a83bb25.1633104510.git.naveen.n.rao@linux.vnet.ibm.com (mailing list archive)
State Superseded
Headers show
Series powerpc/bpf: Various fixes | expand
Related show

Commit Message

Naveen N. Rao Oct. 1, 2021, 9:14 p.m. UTC 
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>
---
 arch/powerpc/net/bpf_jit_comp64.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

Comments

Song Liu Oct. 1, 2021, 9:55 p.m. UTC | #1 
On Fri, Oct 1, 2021 at 2:16 PM Naveen N. Rao
<naveen.n.rao@linux.vnet.ibm.com> wrote:
>
> 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>

Acked-by: Song Liu <songliubraving@fb.com>

> ---
>  arch/powerpc/net/bpf_jit_comp64.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
> index 3351a866ef6207..ffb7a2877a8469 100644
> --- a/arch/powerpc/net/bpf_jit_comp64.c
> +++ b/arch/powerpc/net/bpf_jit_comp64.c
> @@ -391,8 +391,14 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
>                 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)) {
> --
> 2.33.0
>
Johan Almbladh Oct. 2, 2021, 5:32 p.m. UTC | #2 
On Fri, Oct 1, 2021 at 11:15 PM Naveen N. Rao
<naveen.n.rao@linux.vnet.ibm.com> wrote:
>
> 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>

Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>

> ---
>  arch/powerpc/net/bpf_jit_comp64.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
> index 3351a866ef6207..ffb7a2877a8469 100644
> --- a/arch/powerpc/net/bpf_jit_comp64.c
> +++ b/arch/powerpc/net/bpf_jit_comp64.c
> @@ -391,8 +391,14 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
>                 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)) {
> --
> 2.33.0
>
diff mbox series

Patch

diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index 3351a866ef6207..ffb7a2877a8469 100644
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -391,8 +391,14 @@  int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
 		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)) {