In the Linux kernel, the following vulnerability has been resolved:
cassini: Fix a memory leak in the error handling path of cas_init_one()
cas_saturn_firmware_init() allocates some memory using vmalloc(). This
memory is freed in the .remove() function but not it the error handling
path of the probe.
Add the missing vfree() to avoid a memory leak, should an error occur.
In the Linux kernel, the following vulnerability has been resolved:
media: uvcvideo: Handle cameras with invalid descriptors
If the source entity does not contain any pads, do not create a link.
In the Linux kernel, the following vulnerability has been resolved:
x86/MCE: Always save CS register on AMD Zen IF Poison errors
The Instruction Fetch (IF) units on current AMD Zen-based systems do not
guarantee a synchronous #MC is delivered for poison consumption errors.
Therefore, MCG_STATUS[EIPV|RIPV] will not be set. However, the
microarchitecture does guarantee that the exception is delivered within
the same context. In other words, the exact rIP is not known, but the
context is known to not have changed.
There is no architecturally-defined method to determine this behavior.
The Code Segment (CS) register is always valid on such IF unit poison
errors regardless of the value of MCG_STATUS[EIPV|RIPV].
Add a quirk to save the CS register for poison consumption from the IF
unit banks.
This is needed to properly determine the context of the error.
Otherwise, the severity grading function will assume the context is
IN_KERNEL due to the m->cs value being 0 (the initialized value). This
leads to unnecessary kernel panics on data poison errors due to the
kernel believing the poison consumption occurred in kernel context.
In the Linux kernel, the following vulnerability has been resolved:
media: platform: mediatek: vpu: fix NULL ptr dereference
If pdev is NULL, then it is still dereferenced.
This fixes this smatch warning:
drivers/media/platform/mediatek/vpu/mtk_vpu.c:570 vpu_load_firmware() warn: address of NULL pointer 'pdev'
In the Linux kernel, the following vulnerability has been resolved:
btrfs: don't check PageError in __extent_writepage
__extent_writepage currenly sets PageError whenever any error happens,
and the also checks for PageError to decide if to call error handling.
This leads to very unclear responsibility for cleaning up on errors.
In the VM and generic writeback helpers the basic idea is that once
I/O is fired off all error handling responsibility is delegated to the
end I/O handler. But if that end I/O handler sets the PageError bit,
and the submitter checks it, the bit could in some cases leak into the
submission context for fast enough I/O.
Fix this by simply not checking PageError and just using the local
ret variable to check for submission errors. This also fundamentally
solves the long problem documented in a comment in __extent_writepage
by never leaking the error bit into the submission context.
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sysfs: Fix attempting to call device_add multiple times
device_add shall not be called multiple times as stated in its
documentation:
'Do not call this routine or device_register() more than once for
any device structure'
Syzkaller reports a bug as follows [1]:
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:33!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[...]
Call Trace:
<TASK>
__list_add include/linux/list.h:69 [inline]
list_add_tail include/linux/list.h:102 [inline]
kobj_kset_join lib/kobject.c:164 [inline]
kobject_add_internal+0x18f/0x8f0 lib/kobject.c:214
kobject_add_varg lib/kobject.c:358 [inline]
kobject_add+0x150/0x1c0 lib/kobject.c:410
device_add+0x368/0x1e90 drivers/base/core.c:3452
hci_conn_add_sysfs+0x9b/0x1b0 net/bluetooth/hci_sysfs.c:53
hci_le_cis_estabilished_evt+0x57c/0xae0 net/bluetooth/hci_event.c:6799
hci_le_meta_evt+0x2b8/0x510 net/bluetooth/hci_event.c:7110
hci_event_func net/bluetooth/hci_event.c:7440 [inline]
hci_event_packet+0x63d/0xfd0 net/bluetooth/hci_event.c:7495
hci_rx_work+0xae7/0x1230 net/bluetooth/hci_core.c:4007
process_one_work+0x991/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
rcu: Protect rcu_print_task_exp_stall() ->exp_tasks access
For kernels built with CONFIG_PREEMPT_RCU=y, the following scenario can
result in a NULL-pointer dereference:
CPU1 CPU2
rcu_preempt_deferred_qs_irqrestore rcu_print_task_exp_stall
if (special.b.blocked) READ_ONCE(rnp->exp_tasks) != NULL
raw_spin_lock_rcu_node
np = rcu_next_node_entry(t, rnp)
if (&t->rcu_node_entry == rnp->exp_tasks)
WRITE_ONCE(rnp->exp_tasks, np)
....
raw_spin_unlock_irqrestore_rcu_node
raw_spin_lock_irqsave_rcu_node
t = list_entry(rnp->exp_tasks->prev,
struct task_struct, rcu_node_entry)
(if rnp->exp_tasks is NULL, this
will dereference a NULL pointer)
The problem is that CPU2 accesses the rcu_node structure's->exp_tasks
field without holding the rcu_node structure's ->lock and CPU2 did
not observe CPU1's change to rcu_node structure's ->exp_tasks in time.
Therefore, if CPU1 sets rcu_node structure's->exp_tasks pointer to NULL,
then CPU2 might dereference that NULL pointer.
This commit therefore holds the rcu_node structure's ->lock while
accessing that structure's->exp_tasks field.
[ paulmck: Apply Frederic Weisbecker feedback. ]
In the Linux kernel, the following vulnerability has been resolved:
NFSD: Protect against send buffer overflow in NFSv2 READ
Since before the git era, NFSD has conserved the number of pages
held by each nfsd thread by combining the RPC receive and send
buffers into a single array of pages. This works because there are
no cases where an operation needs a large RPC Call message and a
large RPC Reply at the same time.
Once an RPC Call has been received, svc_process() updates
svc_rqst::rq_res to describe the part of rq_pages that can be
used for constructing the Reply. This means that the send buffer
(rq_res) shrinks when the received RPC record containing the RPC
Call is large.
A client can force this shrinkage on TCP by sending a correctly-
formed RPC Call header contained in an RPC record that is
excessively large. The full maximum payload size cannot be
constructed in that case.