X-Git-Url: https://git.tcpdump.org/libpcap/blobdiff_plain/4d6e12cd183cda6eade8cac4244089cee0048c7e..71abe040fa49dfcb8ba3e08e5f21896b0c7cc6e8:/gencode.c

diff --git a/gencode.c b/gencode.c
index 15cb9347..09f72d43 100644
--- a/gencode.c
+++ b/gencode.c
@@ -7466,7 +7466,13 @@ gen_arth(compiler_state_t *cstate, int code, struct arth *a0,
 		if (a1->s->s.code == (BPF_LD|BPF_IMM) && a1->s->s.k == 0)
 			bpf_error(cstate, "modulus by zero");
 	} else if (code == BPF_LSH || code == BPF_RSH) {
-		if (a1->s->s.code == (BPF_LD|BPF_IMM) && a1->s->s.k > 31)
+		/*
+		 * XXX - we need to make up our minds as to what integers
+		 * are signed and what integers are unsigned in BPF programs
+		 * and in our IR.
+		 */
+		if (a1->s->s.code == (BPF_LD|BPF_IMM) &&
+		    (a1->s->s.k < 0 || a1->s->s.k > 31))
 			bpf_error(cstate, "shift by more than 31 bits");
 	}
 	s0 = xfer_to_x(cstate, a1);
@@ -8568,7 +8574,7 @@ gen_vlan(compiler_state_t *cstate, int vlan_num)
  * support for MPLS
  */
 struct block *
-gen_mpls(compiler_state_t *cstate, int label_num)
+gen_mpls(compiler_state_t *cstate, bpf_u_int32 label_num, int has_label_num)
 {
 	struct	block	*b0, *b1;
 
@@ -8606,7 +8612,11 @@ gen_mpls(compiler_state_t *cstate, int label_num)
         }
 
 	/* If a specific MPLS label is requested, check it */
-	if (label_num >= 0) {
+	if (has_label_num) {
+		if (label_num > 0xFFFFF) {
+			bpf_error(cstate, "MPLS label %u greater than maximum %u",
+			    label_num, 0xFFFFF);
+		}
 		label_num = label_num << 12; /* label is shifted 12 bits on the wire */
 		b1 = gen_mcmp(cstate, OR_LINKPL, 0, BPF_W, (bpf_int32)label_num,
 		    0xfffff000); /* only compare the first 20 bits */