svn commit: r362311 - stable/12/sys/dev/mlx5/mlx5_en

[Hans Petter Selasky]

Author: hselasky
Date: Thu Jun 18 10:38:02 2020
New Revision: 362311
URL: https://svnweb.freebsd.org/changeset/base/362311

Log:
  MFC r362045:
  Make sure packets generated by raw IP code is let through by mlx5en(4).
  
  Allow the TCP header to reside in the mbuf following the IP header.
  Else such packets will get dropped.
  
  Backtrace:
  mlx5e_sq_xmit()
  mlx5e_xmit()
  ether_output_frame()
  ether_output()
  ip_output_send()
  ip_output()
  rip_output()
  sosend_generic()
  sosend()
  kern_sendit()
  sendit()
  sys_sendto()
  amd64_syscall()
  fast_syscall_common()
  
  Sponsored by:	Mellanox Technologies

Modified:
  stable/12/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c
==============================================================================
--- stable/12/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c	Thu Jun 18 10:31:21 2020	(r362310)
+++ stable/12/sys/dev/mlx5/mlx5_en/mlx5_en_tx.c	Thu Jun 18 10:38:02 2020	(r362311)
@@ -281,9 +281,15 @@ mlx5e_get_full_header_size(const struct mbuf *mb)
 	default:
 		return (0);
 	}
-	if (unlikely(mb->m_len < eth_hdr_len + sizeof(*th)))
-		return (0);
-	th = (const struct tcphdr *)(mb->m_data + eth_hdr_len);
+	if (unlikely(mb->m_len < eth_hdr_len + sizeof(*th))) {
+		const struct mbuf *m_th = mb->m_next;
+		if (unlikely(mb->m_len != eth_hdr_len ||
+		    m_th == NULL || m_th->m_len < sizeof(*th)))
+			return (0);
+		th = (const struct tcphdr *)(m_th->m_data);
+	} else {
+		th = (const struct tcphdr *)(mb->m_data + eth_hdr_len);
+	}
 	tcp_hlen = th->th_off << 2;
 	eth_hdr_len += tcp_hlen;
 done: