svn commit: r362168 - stable/10/sys/dev/usb/net

[Hans Petter Selasky]

Author: hselasky
Date: Sun Jun 14 05:33:25 2020
New Revision: 362168
URL: https://svnweb.freebsd.org/changeset/base/362168

Log:
  MFC r362056:
  Add missing range checks when receiving USB ethernet packets.
  
  Found by:	Ilja Van Sprundel, IOActive
  Sponsored by:	Mellanox Technologies

Modified:
  stable/10/sys/dev/usb/net/if_smsc.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/dev/usb/net/if_smsc.c
==============================================================================
--- stable/10/sys/dev/usb/net/if_smsc.c	Sun Jun 14 05:27:37 2020	(r362167)
+++ stable/10/sys/dev/usb/net/if_smsc.c	Sun Jun 14 05:33:25 2020	(r362168)
@@ -949,7 +949,7 @@ smsc_bulk_read_callback(struct usb_xfer *xfer, usb_err
 	struct mbuf *m;
 	struct usb_page_cache *pc;
 	uint32_t rxhdr;
-	uint16_t pktlen;
+	int pktlen;
 	int off;
 	int actlen;
 
@@ -975,6 +975,9 @@ smsc_bulk_read_callback(struct usb_xfer *xfer, usb_err
 			/* The frame header is always aligned on a 4 byte boundary */
 			off = ((off + 0x3) & ~0x3);
 
+			if ((off + sizeof(rxhdr)) > actlen)
+				goto tr_setup;
+
 			usbd_copy_out(pc, off, &rxhdr, sizeof(rxhdr));
 			off += (sizeof(rxhdr) + ETHER_ALIGN);
 			rxhdr = le32toh(rxhdr);
@@ -1003,7 +1006,13 @@ smsc_bulk_read_callback(struct usb_xfer *xfer, usb_err
 					ifp->if_iqdrops++;
 					goto tr_setup;
 				}
-				
+				if (pktlen > m->m_len) {
+					smsc_dbg_printf(sc, "buffer too small %d vs %d bytes",
+					    pktlen, m->m_len);
+					if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
+					m_freem(m);
+					goto tr_setup;
+				}
 				usbd_copy_out(pc, off, mtod(m, uint8_t *), pktlen);
 
 				/* Check if RX TCP/UDP checksumming is being offloaded */