Le 01/07/2021 à 17:08, Naveen N. Rao a écrit :
Commit 91c960b0056672 ("bpf: Rename BPF_XADD and prepare to encode other
atomics in .imm") converted BPF_XADD to BPF_ATOMIC and updated all JIT
implementations to reject JIT'ing instructions with an immediate value
different from BPF_ADD. However, ppc32 BPF JIT was implemented around
the same time and didn't include the same change. Update the ppc32 JIT
accordingly.
Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Shouldn't it also include a Fixes tag and stable Cc as PPC32 eBPF was added in 5.13 ?
Fixes: 51c66ad849a7 ("powerpc/bpf: Implement extended BPF on PPC32")
Cc: stable@xxxxxxxxxxxxxxx
---
arch/powerpc/net/bpf_jit_comp32.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c
index cbe5b399ed869d..91c990335a16c9 100644
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -773,9 +773,17 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
break;
/*
- * BPF_STX XADD (atomic_add)
+ * BPF_STX ATOMIC (atomic ops)
*/
- case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ if (imm != BPF_ADD) {
+ pr_err_ratelimited(
+ "eBPF filter atomic op code %02x (@%d) unsupported\n", code, i);
+ return -ENOTSUPP;
+ }
+
+ /* *(u32 *)(dst + off) += src */
+
bpf_set_seen_register(ctx, tmp_reg);
/* Get offset into TMP_REG */
EMIT(PPC_RAW_LI(tmp_reg, off));
@@ -789,7 +797,7 @@ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *
PPC_BCC_SHORT(COND_NE, (ctx->idx - 3) * 4);
break;
- case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */
+ case BPF_STX | BPF_ATOMIC | BPF_DW: /* *(u64 *)(dst + off) += src */
return -EOPNOTSUPP;
/*
