From: Jorgen Hansen <jhansen@xxxxxxxxxx> [ 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@xxxxxxxxx> Reviewed-by: Adit Ranadive <aditr@xxxxxxxxxx> Reviewed-by: Vishnu Dasa <vdasa@xxxxxxxxxx> Signed-off-by: Jorgen Hansen <jhansen@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/misc/vmw_vmci/vmci_driver.c | 2 +- drivers/misc/vmw_vmci/vmci_resource.c | 3 ++- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/misc/vmw_vmci/vmci_driver.c b/drivers/misc/vmw_vmci/vmci_driver.c index d7eaf1eb11e7..003bfba40758 100644 --- 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 9a53a30de445..f1164602cec1 100644 --- 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; } -- 2.17.1