[PATCH 4.11 020/115] net/smc: Add warning about remote memory exposure

[Greg Kroah-Hartman]

4.11-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Christoph Hellwig <hch@xxxxxx>


[ Upstream commit 19a0f7e37c0761a0a1cbf550705a6063c9675223 ]

The driver explicitly bypasses APIs to register all memory once a
connection is made, and thus allows remote access to memory.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx>
Acked-by: Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/smc/Kconfig |    4 ++++
 1 file changed, 4 insertions(+)

--- a/net/smc/Kconfig
+++ b/net/smc/Kconfig
@@ -8,6 +8,10 @@ config SMC
 	  The Linux implementation of the SMC-R solution is designed as
 	  a separate socket family SMC.
 
+	  Warning: SMC will expose all memory for remote reads and writes
+	  once a connection is established.  Don't enable this option except
+	  for tightly controlled lab environment.
+
 	  Select this option if you want to run SMC socket applications
 
 config SMC_DIAG