From: Daniel Borkmann daniel@iogearbox.net
[ Upstream commit 9601148392520e2e134936e76788fc2a6371e7be ]
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: 2c78ee898d8f ("bpf: Implement CAP_BPF") Signed-off-by: Daniel Borkmann daniel@iogearbox.net Reviewed-by: John Fastabend john.fastabend@gmail.com Acked-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/bpf/verifier.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 36b81975d9cd..b654174619e5 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5578,7 +5578,7 @@ 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;