[5/6] vhost: fix potential memory space leak

Message ID 20200518131704.715877-6-ferruh.yigit@intel.com (mailing list archive)
State Accepted, archived
Delegated to: David Marchand
Headers
Series Fix vhost security issues |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK

Commit Message

Ferruh Yigit May 18, 2020, 1:17 p.m. UTC
  From: Xiaolong Ye <xiaolong.ye@intel.com>

A malicious container which has direct access to the vhost-user socket
can keep sending VHOST_USER_GET_INFLIGHT_FD messages which may cause
leaking resources until resulting a DOS. Fix it by unmapping the
dev->inflight_info->addr before assigning new mapped addr to it.

CVE-2020-10726
Fixes: d87f1a1cb7b6 ("vhost: support inflight info sharing")
Cc: stable@dpdk.org

Signed-off-by: Xiaolong Ye <xiaolong.ye@intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_vhost/vhost_user.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)
  

Patch

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index e51a8a6b77..0424e49cb8 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -1433,6 +1433,11 @@  vhost_user_get_inflight_fd(struct virtio_net **pdev,
 	}
 	memset(addr, 0, mmap_size);
 
+	if (dev->inflight_info->addr) {
+		munmap(dev->inflight_info->addr, dev->inflight_info->size);
+		dev->inflight_info->addr = NULL;
+	}
+
 	dev->inflight_info->addr = addr;
 	dev->inflight_info->size = msg->payload.inflight.mmap_size = mmap_size;
 	dev->inflight_info->fd = msg->fds[0] = fd;
@@ -1517,8 +1522,10 @@  vhost_user_set_inflight_fd(struct virtio_net **pdev, VhostUserMsg *msg,
 		}
 	}
 
-	if (dev->inflight_info->addr)
+	if (dev->inflight_info->addr) {
 		munmap(dev->inflight_info->addr, dev->inflight_info->size);
+		dev->inflight_info->addr = NULL;
+	}
 
 	addr = mmap(0, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED,
 		    fd, mmap_offset);