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[v2,03/10] powerpc/bpf: Fix BPF_MOD when imm == 1

Message ID c674ca18c3046885602caebb326213731c675d06.1633464148.git.naveen.n.rao@linux.vnet.ibm.com (mailing list archive)
State Accepted
Headers show
Series powerpc/bpf: Various fixes | expand
Related show

Commit Message

Naveen N. Rao Oct. 5, 2021, 8:25 p.m. UTC 
Only ignore the operation if dividing by 1.

Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
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

Christophe Leroy Oct. 6, 2021, 4:52 a.m. UTC | #1 
Le 05/10/2021 à 22:25, Naveen N. Rao a écrit :
> Only ignore the operation if dividing by 1.
> 
> Acked-by: Song Liu <songliubraving@fb.com>
> Acked-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
> Tested-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
> Fixes: 156d0e290e969c ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF")
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>

Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>

> ---
>   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 f06c62089b1457..d67f6d62e2e1ff 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)) {
>
diff mbox series

Patch

diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
index f06c62089b1457..d67f6d62e2e1ff 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)) {