git: b85c68857da3 - releng/13.0 - bhyve: validate e82545 checksum offset field

The branch releng/13.0 has been updated by emaste:

URL: https://cgit.FreeBSD.org/src/commit/?id=b85c68857da3fdd833c4c146e2f5f49f4c16b0d7

commit b85c68857da3fdd833c4c146e2f5f49f4c16b0d7
Author:     Mark Johnston <markj@FreeBSD.org>
AuthorDate: 2022-04-05 23:26:02 +0000
Commit:     Ed Maste <emaste@FreeBSD.org>
CommitDate: 2022-04-05 23:26:02 +0000

    bhyve: validate e82545 checksum offset field
    
    Reported by:    Mehdi Talbi, Synacktiv
    
    (cherry picked from commit b0aa20bec5db244980a0248e24dd6b8e1e68c4d0)
    (cherry picked from commit 53f72209479885dfa6a7e6ed68cbc82c68464f4b)
    
    Approved by:    so
    Security:       CVE-2022-23087
    Security:       FreeBSD-SA-22:05.bhyve
---
 usr.sbin/bhyve/pci_e82545.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/usr.sbin/bhyve/pci_e82545.c b/usr.sbin/bhyve/pci_e82545.c
index 2d09c024f258..9581e616c76c 100644
--- a/usr.sbin/bhyve/pci_e82545.c
+++ b/usr.sbin/bhyve/pci_e82545.c
@@ -1277,9 +1277,7 @@ e82545_transmit(struct e82545_softc *sc, uint16_t head, uint16_t tail,
 			goto done;
 		}
 		if (sc->esc_txctx.cmd_and_length & E1000_TXD_CMD_TCP) {
-			if (hdrlen < ckinfo[1].ck_start + 14 ||
-			    (ckinfo[1].ck_valid &&
-			    hdrlen < ckinfo[1].ck_off + 2)) {
+			if (hdrlen < ckinfo[1].ck_start + 14) {
 				WPRINTF("TSO hdrlen too small for TCP fields "
 				    "(%d) -- dropped", hdrlen);
 				goto done;
@@ -1291,6 +1289,11 @@ e82545_transmit(struct e82545_softc *sc, uint16_t head, uint16_t tail,
 				goto done;
 			}
 		}
+		if (ckinfo[1].ck_valid && hdrlen < ckinfo[1].ck_off + 2) {
+			WPRINTF("TSO hdrlen too small for TCP/UDP fields "
+			    "(%d) -- dropped", hdrlen);
+			goto done;
+		}
 	}
 
 	/* Allocate, fill and prepend writable header vector. */