VMCI: Resource wildcard match fixed

[ Upstream commit 11924ba5e671d6caef1516923e2bd8c72929a3fe ]

When adding a VMCI resource, the check for an existing entry
would ignore that the new entry could be a wildcard. This could
result in multiple resource entries that would match a given
handle. One disastrous outcome of this is that the
refcounting used to ensure that delayed callbacks for VMCI
datagrams have run before the datagram is destroyed can be
wrong, since the refcount could be increased on the duplicate
entry. This in turn leads to a use after free bug. This issue
was discovered by Hangbin Liu using KASAN and syzkaller.

Fixes: bc63dedb7d46 ("VMCI: resource object implementation")
Reported-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/vmw_vmci/vmci_driver.c b/drivers/misc/vmw_vmci/vmci_driver.c
index d7eaf1eb11e7f3e67646dd7da053213a78fd35bd..003bfba407588cdcec306822050eb18b9a86e40b 100644 (file)
--- a/drivers/misc/vmw_vmci/vmci_driver.c
+++ b/drivers/misc/vmw_vmci/vmci_driver.c
@@ -113,5 +113,5 @@ module_exit(vmci_drv_exit);
 
 MODULE_AUTHOR("VMware, Inc.");
 MODULE_DESCRIPTION("VMware Virtual Machine Communication Interface.");
-MODULE_VERSION("1.1.5.0-k");
+MODULE_VERSION("1.1.6.0-k");
 MODULE_LICENSE("GPL v2");

diff --git a/drivers/misc/vmw_vmci/vmci_resource.c b/drivers/misc/vmw_vmci/vmci_resource.c
index 9a53a30de445cfb7b68080dccc6e6474c0f4c52d..f1164602cec1743711673b97a50bee689160b5df 100644 (file)
--- a/drivers/misc/vmw_vmci/vmci_resource.c
+++ b/drivers/misc/vmw_vmci/vmci_resource.c
@@ -56,7 +56,8 @@ static struct vmci_resource *vmci_resource_lookup(struct vmci_handle handle,
 
                if (r->type == type &&
                    rid == handle.resource &&
-                   (cid == handle.context || cid == VMCI_INVALID_ID)) {
+                   (cid == handle.context || cid == VMCI_INVALID_ID ||
+                    handle.context == VMCI_INVALID_ID)) {
                        resource = r;
                        break;
                }