[PATCH bpf-next v2 2/5] bpf/verifier: improve XOR and OR range computation

[Cupertino Miranda <cupertino.miranda@oracle.com>]

Range for XOR and OR operators would not be attempted unless src_reg
would resolve to a single value, i.e. a known constant value.
This condition is unnecessary, and the following XOR/OR operator
handling could compute a possible better range.

Signed-off-by: Cupertino Miranda <cupertino.miranda@oracle.com
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: David Faust <david.faust@oracle.com>
Cc: Jose Marchesi <jose.marchesi@oracle.com
Cc: Elena Zannoni <elena.zannoni@oracle.com>
---
 kernel/bpf/verifier.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 0aa6580af7a2..f410eb027e25 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -13453,12 +13453,12 @@ static int is_safe_to_compute_dst_reg_range(struct bpf_insn *insn,
 	case BPF_ADD:
 	case BPF_SUB:
 	case BPF_AND:
+	case BPF_XOR:
+	case BPF_OR:
 		return COMPUTABLE_RANGE;
 
 	/* Compute range for the following only if the src_reg is known.
 	 */
-	case BPF_XOR:
-	case BPF_OR:
 	case BPF_MUL:
 		return src_known ? COMPUTABLE_RANGE : UNCOMPUTABLE_RANGE;
 
-- 
2.39.2