From: He Fengqing <hefengqing@huawei.com> hulk inclusion category: bugfix bugzilla: NA CVE: CVE-2021-3444 ------------------------------------------------- This reverts commit 946dd60de74146a418f62275e5a6f83496f74dcd. Signed-off-by: He Fengqing <hefengqing@huawei.com> Reviewed-by: Kuohai Xu <xukuohai@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- kernel/bpf/verifier.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 962dc7c48430f..61a535eec0a9b 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -6322,7 +6322,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) bool isdiv = BPF_OP(insn->code) == BPF_DIV; struct bpf_insn *patchlet; struct bpf_insn chk_and_div[] = { - /* [R,W]x div 0 -> 0 */ + /* Rx div 0 -> 0 */ BPF_RAW_INSN((is64 ? BPF_JMP : BPF_JMP32) | BPF_JNE | BPF_K, insn->src_reg, 0, 2, 0), @@ -6331,18 +6331,16 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env) *insn, }; struct bpf_insn chk_and_mod[] = { - /* [R,W]x mod 0 -> [R,W]x */ + /* Rx mod 0 -> Rx */ BPF_RAW_INSN((is64 ? BPF_JMP : BPF_JMP32) | BPF_JEQ | BPF_K, insn->src_reg, - 0, 1 + (is64 ? 0 : 1), 0), + 0, 1, 0), *insn, - BPF_JMP_IMM(BPF_JA, 0, 0, 1), - BPF_MOV32_REG(insn->dst_reg, insn->dst_reg), }; patchlet = isdiv ? chk_and_div : chk_and_mod; cnt = isdiv ? ARRAY_SIZE(chk_and_div) : - ARRAY_SIZE(chk_and_mod) - (is64 ? 2 : 0); + ARRAY_SIZE(chk_and_mod); new_prog = bpf_patch_insn_data(env, i + delta, patchlet, cnt); if (!new_prog) -- 2.25.1