summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorPu Lehui <pulehui@huawei.com>2023-08-24 09:49:55 +0000
committerAlexei Starovoitov <ast@kernel.org>2023-08-24 09:13:08 -0700
commit469fb2c3c1bbaa092f541e3a8d3b3554042aa6a5 (patch)
treed5eb570a44e9525e6ca5706b927d3fcc145a1505
parent1b580c9bb63414903cfb414571e92e4fd36d6969 (diff)
riscv, bpf: Fix missing exception handling and redundant zext for LDX_B/H/W
For LDX_B/H/W, when zext has been inserted by verifier, it'll return 1, and no exception handling will continue. Also, when the offset is 12-bit value, the redundant zext inserted by the verifier is not removed. Fix both scenarios by moving down the removal of redundant zext. Signed-off-by: Pu Lehui <pulehui@huawei.com> Link: https://lore.kernel.org/r/20230824095001.3408573-2-pulehui@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
-rw-r--r--arch/riscv/net/bpf_jit_comp64.c9
1 files changed, 3 insertions, 6 deletions
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index 0ca4f5c0097c..f2644e7ea6b5 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -1512,8 +1512,6 @@ out_be:
insns_start = ctx->ninsns;
emit(rv_lbu(rd, 0, RV_REG_T1), ctx);
insn_len = ctx->ninsns - insns_start;
- if (insn_is_zext(&insn[1]))
- return 1;
break;
case BPF_H:
if (is_12b_int(off)) {
@@ -1528,8 +1526,6 @@ out_be:
insns_start = ctx->ninsns;
emit(rv_lhu(rd, 0, RV_REG_T1), ctx);
insn_len = ctx->ninsns - insns_start;
- if (insn_is_zext(&insn[1]))
- return 1;
break;
case BPF_W:
if (is_12b_int(off)) {
@@ -1544,8 +1540,6 @@ out_be:
insns_start = ctx->ninsns;
emit(rv_lwu(rd, 0, RV_REG_T1), ctx);
insn_len = ctx->ninsns - insns_start;
- if (insn_is_zext(&insn[1]))
- return 1;
break;
case BPF_DW:
if (is_12b_int(off)) {
@@ -1566,6 +1560,9 @@ out_be:
ret = add_exception_handler(insn, ctx, rd, insn_len);
if (ret)
return ret;
+
+ if (BPF_SIZE(code) != BPF_DW && insn_is_zext(&insn[1]))
+ return 1;
break;
}
/* speculation barrier */