In the Linux kernel, the following vulnerability has been resolved:
Drivers: hv: vmbus: Don't free ring buffers that couldn't be re-encrypted
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
The VMBus ring buffer code could free decrypted/shared pages if
set_memory_decrypted() fails. Check the decrypted field in the struct
vmbus_gpadl for the ring buffers to decide whether to free the memory.
In the Linux kernel, the following vulnerability has been resolved:
uio_hv_generic: Don't free decrypted memory
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
The VMBus device UIO driver could free decrypted/shared pages if
set_memory_decrypted() fails. Check the decrypted field in the gpadl
to decide whether to free the memory.
In the Linux kernel, the following vulnerability has been resolved:
hv_netvsc: Don't free decrypted memory
In CoCo VMs it is possible for the untrusted host to cause
set_memory_encrypted() or set_memory_decrypted() to fail such that an
error is returned and the resulting memory is shared. Callers need to
take care to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional or security
issues.
The netvsc driver could free decrypted/shared pages if
set_memory_decrypted() fails. Check the decrypted field in the gpadl
to decide whether to free the memory.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Atom Integrated System Info v2_2 for DCN35
New request from KMD/VBIOS in order to support new UMA carveout
model. This fixes a null dereference from accessing
Ctx->dc_bios->integrated_info while it was NULL.
DAL parses through the BIOS and extracts the necessary
integrated_info but was missing a case for the new BIOS
version 2.3.
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: tcpm: Check for port partner validity before consuming it
typec_register_partner() does not guarantee partner registration
to always succeed. In the event of failure, port->partner is set
to the error value or NULL. Given that port->partner validity is
not checked, this results in the following crash:
Unable to handle kernel NULL pointer dereference at virtual address xx
pc : run_state_machine+0x1bc8/0x1c08
lr : run_state_machine+0x1b90/0x1c08
..
Call trace:
run_state_machine+0x1bc8/0x1c08
tcpm_state_machine_work+0x94/0xe4
kthread_worker_fn+0x118/0x328
kthread+0x1d0/0x23c
ret_from_fork+0x10/0x20
To prevent the crash, check for port->partner validity before
derefencing it in all the call sites.
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_fs: Fix race between aio_cancel() and AIO request complete
FFS based applications can utilize the aio_cancel() callback to dequeue
pending USB requests submitted to the UDC. There is a scenario where the
FFS application issues an AIO cancel call, while the UDC is handling a
soft disconnect. For a DWC3 based implementation, the callstack looks
like the following:
DWC3 Gadget FFS Application
dwc3_gadget_soft_disconnect() ...
--> dwc3_stop_active_transfers()
--> dwc3_gadget_giveback(-ESHUTDOWN)
--> ffs_epfile_async_io_complete() ffs_aio_cancel()
--> usb_ep_free_request() --> usb_ep_dequeue()
There is currently no locking implemented between the AIO completion
handler and AIO cancel, so the issue occurs if the completion routine is
running in parallel to an AIO cancel call coming from the FFS application.
As the completion call frees the USB request (io_data->req) the FFS
application is also referencing it for the usb_ep_dequeue() call. This can
lead to accessing a stale/hanging pointer.
commit b566d38857fc ("usb: gadget: f_fs: use io_data->status consistently")
relocated the usb_ep_free_request() into ffs_epfile_async_io_complete().
However, in order to properly implement locking to mitigate this issue, the
spinlock can't be added to ffs_epfile_async_io_complete(), as
usb_ep_dequeue() (if successfully dequeuing a USB request) will call the
function driver's completion handler in the same context. Hence, leading
into a deadlock.
Fix this issue by moving the usb_ep_free_request() back to
ffs_user_copy_worker(), and ensuring that it explicitly sets io_data->req
to NULL after freeing it within the ffs->eps_lock. This resolves the race
condition above, as the ffs_aio_cancel() routine will not continue
attempting to dequeue a request that has already been freed, or the
ffs_user_copy_work() not freeing the USB request until the AIO cancel is
done referencing it.
This fix depends on
commit b566d38857fc ("usb: gadget: f_fs: use io_data->status
consistently")
In the Linux kernel, the following vulnerability has been resolved:
net: fix out-of-bounds access in ops_init
net_alloc_generic is called by net_alloc, which is called without any
locking. It reads max_gen_ptrs, which is changed under pernet_ops_rwsem. It
is read twice, first to allocate an array, then to set s.len, which is
later used to limit the bounds of the array access.
It is possible that the array is allocated and another thread is
registering a new pernet ops, increments max_gen_ptrs, which is then used
to set s.len with a larger than allocated length for the variable array.
Fix it by reading max_gen_ptrs only once in net_alloc_generic. If
max_gen_ptrs is later incremented, it will be caught in net_assign_generic.