bpf: Use correct permission flag for mixed signed bounds arithmetic

stable inclusion
from stable-5.10.32
commit 4f3ff11204eac0ee23acf64deecb3bad7b0db0c6
bugzilla: 51796

--------------------------------

[ Upstream commit 96011483 ]

We forbid adding unknown scalars with mixed signed bounds due to the
spectre v1 masking mitigation. Hence this also needs bypass_spec_v1
flag instead of allow_ptr_leaks.

Fixes: 2c78ee89 ("bpf: Implement CAP_BPF")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: NJohn Fastabend <john.fastabend@gmail.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

kernel/bpf/verifier.c

@@ -5522,7 +5522,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env,
 			dst, reg_type_str[ptr_reg->type]);
 		return -EACCES;
 	case PTR_TO_MAP_VALUE:
-		if (!env->allow_ptr_leaks && !known && (smin_val < 0) != (smax_val < 0)) {
+		if (!env->env->bypass_spec_v1 && !known && (smin_val < 0) != (smax_val < 0)) {
 			verbose(env, "R%d has unknown scalar with mixed signed bounds, pointer arithmetic with it prohibited for !root\n",
 				off_reg == dst_reg ? dst : src);
 			return -EACCES;