From: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
commit f9320c49993ca3c0ec0f9a7026b313735306bb8b upstream.
These instructions are updated after the initial JIT, so redo codegen
during the extra pass. Rename bpf_jit_fixup_subprog_calls() to clarify
that this is more than just subprog calls.
Fixes: 69c087ba6225b5 ("bpf: Add bpf_for_each_map_elem() helper")
Cc: stable@xxxxxxxxxxxxxxx # v5.15
Signed-off-by: Naveen N. Rao <naveen.n.rao@xxxxxxxxxxxxxxxxxx>
Tested-by: Jiri Olsa <jolsa@xxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/7cc162af77ba918eb3ecd26ec9e7824bc44b1fae.1641468127.git.naveen.n.rao@xxxxxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/powerpc/net/bpf_jit_comp.c | 29 +++++++++++++++++++++++------
arch/powerpc/net/bpf_jit_comp32.c | 6 ++++++
arch/powerpc/net/bpf_jit_comp64.c | 7 ++++++-
3 files changed, 35 insertions(+), 7 deletions(-)
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -23,15 +23,15 @@ static void bpf_jit_fill_ill_insns(void
memset32(area, BREAKPOINT_INSTRUCTION, size / 4);
}
-/* Fix the branch target addresses for subprog calls */
-static int bpf_jit_fixup_subprog_calls(struct bpf_prog *fp, u32 *image,
- struct codegen_context *ctx, u32 *addrs)
+/* Fix updated addresses (for subprog calls, ldimm64, et al) during extra pass */
+static int bpf_jit_fixup_addresses(struct bpf_prog *fp, u32 *image,
+ struct codegen_context *ctx, u32 *addrs)
{
const struct bpf_insn *insn = fp->insnsi;
bool func_addr_fixed;
u64 func_addr;
u32 tmp_idx;
- int i, ret;
+ int i, j, ret;
for (i = 0; i < fp->len; i++) {
/*
@@ -66,6 +66,23 @@ static int bpf_jit_fixup_subprog_calls(s
* of the JITed sequence remains unchanged.
*/
ctx->idx = tmp_idx;
+ } else if (insn[i].code == (BPF_LD | BPF_IMM | BPF_DW)) {
+ tmp_idx = ctx->idx;
+ ctx->idx = addrs[i] / 4;
+#ifdef CONFIG_PPC32
+ PPC_LI32(ctx->b2p[insn[i].dst_reg] - 1, (u32)insn[i + 1].imm);
+ PPC_LI32(ctx->b2p[insn[i].dst_reg], (u32)insn[i].imm);
+ for (j = ctx->idx - addrs[i] / 4; j < 4; j++)
+ EMIT(PPC_RAW_NOP());
+#else
+ func_addr = ((u64)(u32)insn[i].imm) | (((u64)(u32)insn[i + 1].imm) << 32);
+ PPC_LI64(b2p[insn[i].dst_reg], func_addr);
+ /* overwrite rest with nops */
+ for (j = ctx->idx - addrs[i] / 4; j < 5; j++)
+ EMIT(PPC_RAW_NOP());
+#endif
+ ctx->idx = tmp_idx;
+ i++;
}
}
@@ -193,13 +210,13 @@ skip_init_ctx:
/*
* Do not touch the prologue and epilogue as they will remain
* unchanged. Only fix the branch target address for subprog
- * calls in the body.
+ * calls in the body, and ldimm64 instructions.
*
* This does not change the offsets and lengths of the subprog
* call instruction sequences and hence, the size of the JITed
* image as well.
*/
- bpf_jit_fixup_subprog_calls(fp, code_base, &cgctx, addrs);
+ bpf_jit_fixup_addresses(fp, code_base, &cgctx, addrs);
/* There is no need to perform the usual passes. */
goto skip_codegen_passes;
--- a/arch/powerpc/net/bpf_jit_comp32.c
+++ b/arch/powerpc/net/bpf_jit_comp32.c
@@ -292,6 +292,8 @@ int bpf_jit_build_body(struct bpf_prog *
bool func_addr_fixed;
u64 func_addr;
u32 true_cond;
+ u32 tmp_idx;
+ int j;
/*
* addrs[] maps a BPF bytecode address into a real offset from
@@ -839,8 +841,12 @@ int bpf_jit_build_body(struct bpf_prog *
* 16 byte instruction that uses two 'struct bpf_insn'
*/
case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
+ tmp_idx = ctx->idx;
PPC_LI32(dst_reg_h, (u32)insn[i + 1].imm);
PPC_LI32(dst_reg, (u32)insn[i].imm);
+ /* padding to allow full 4 instructions for later patching */
+ for (j = ctx->idx - tmp_idx; j < 4; j++)
+ EMIT(PPC_RAW_NOP());
/* Adjust for two bpf instructions */
addrs[++i] = ctx->idx * 4;
break;
--- a/arch/powerpc/net/bpf_jit_comp64.c
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -318,6 +318,7 @@ int bpf_jit_build_body(struct bpf_prog *
u64 imm64;
u32 true_cond;
u32 tmp_idx;
+ int j;
/*
* addrs[] maps a BPF bytecode address into a real offset from
@@ -806,9 +807,13 @@ emit_clear:
case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
imm64 = ((u64)(u32) insn[i].imm) |
(((u64)(u32) insn[i+1].imm) << 32);
+ tmp_idx = ctx->idx;
+ PPC_LI64(dst_reg, imm64);
+ /* padding to allow full 5 instructions for later patching */
+ for (j = ctx->idx - tmp_idx; j < 5; j++)
+ EMIT(PPC_RAW_NOP());
/* Adjust for two bpf instructions */
addrs[++i] = ctx->idx * 4;
- PPC_LI64(dst_reg, imm64);
break;
/*
