diff options
author | Vishnu DASA <vdasa@vmware.com> | 2019-05-24 15:13:10 +0000 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-07-14 08:09:51 +0200 |
commit | 95688f33cb29efe90bb31b61e5d604e60ed35498 (patch) | |
tree | 385949877c7dc2678eb9f66e8a446ebbeee73922 /include | |
parent | 9e0150f694944ce0a60a2a23d8cab8925baeb0a8 (diff) |
VMCI: Fix integer overflow in VMCI handle arrays
commit 1c2eb5b2853c9f513690ba6b71072d8eb65da16a upstream.
The VMCI handle array has an integer overflow in
vmci_handle_arr_append_entry when it tries to expand the array. This can be
triggered from a guest, since the doorbell link hypercall doesn't impose a
limit on the number of doorbell handles that a VM can create in the
hypervisor, and these handles are stored in a handle array.
In this change, we introduce a mandatory max capacity for handle
arrays/lists to avoid excessive memory usage.
Signed-off-by: Vishnu Dasa <vdasa@vmware.com>
Reviewed-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/vmw_vmci_defs.h | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/include/linux/vmw_vmci_defs.h b/include/linux/vmw_vmci_defs.h index eaa1e762bf06..6124b4cebb42 100644 --- a/include/linux/vmw_vmci_defs.h +++ b/include/linux/vmw_vmci_defs.h @@ -69,9 +69,18 @@ enum { /* * A single VMCI device has an upper limit of 128MB on the amount of - * memory that can be used for queue pairs. + * memory that can be used for queue pairs. Since each queue pair + * consists of at least two pages, the memory limit also dictates the + * number of queue pairs a guest can create. */ #define VMCI_MAX_GUEST_QP_MEMORY (128 * 1024 * 1024) +#define VMCI_MAX_GUEST_QP_COUNT (VMCI_MAX_GUEST_QP_MEMORY / PAGE_SIZE / 2) + +/* + * There can be at most PAGE_SIZE doorbells since there is one doorbell + * per byte in the doorbell bitmap page. + */ +#define VMCI_MAX_GUEST_DOORBELL_COUNT PAGE_SIZE /* * Queues with pre-mapped data pages must be small, so that we don't pin |