Security Vulnerabilities
- CVEs Published In May 2024
In the Linux kernel, the following vulnerability has been resolved:
arch_topology: Avoid use-after-free for scale_freq_data
Currently topology_scale_freq_tick() (which gets called from
scheduler_tick()) may end up using a pointer to "struct
scale_freq_data", which was previously cleared by
topology_clear_scale_freq_source(), as there is no protection in place
here. The users of topology_clear_scale_freq_source() though needs a
guarantee that the previously cleared scale_freq_data isn't used
anymore, so they can free the related resources.
Since topology_scale_freq_tick() is called from scheduler tick, we don't
want to add locking in there. Use the RCU update mechanism instead
(which is already used by the scheduler's utilization update path) to
guarantee race free updates here.
synchronize_rcu() makes sure that all RCU critical sections that started
before it is called, will finish before it returns. And so the callers
of topology_clear_scale_freq_source() don't need to worry about their
callback getting called anymore.
In the Linux kernel, the following vulnerability has been resolved:
virtio-blk: Fix memory leak among suspend/resume procedure
The vblk->vqs should be freed before we call init_vqs()
in virtblk_restore().
In the Linux kernel, the following vulnerability has been resolved:
nfs: fix acl memory leak of posix_acl_create()
When looking into another nfs xfstests report, I found acl and
default_acl in nfs3_proc_create() and nfs3_proc_mknod() error
paths are possibly leaked. Fix them in advance.
In the Linux kernel, the following vulnerability has been resolved:
watchdog: Fix possible use-after-free by calling del_timer_sync()
This driver's remove path calls del_timer(). However, that function
does not wait until the timer handler finishes. This means that the
timer handler may still be running after the driver's remove function
has finished, which would result in a use-after-free.
Fix by calling del_timer_sync(), which makes sure the timer handler
has finished, and unable to re-schedule itself.
In the Linux kernel, the following vulnerability has been resolved:
NFSv4: Fix an Oops in pnfs_mark_request_commit() when doing O_DIRECT
Fix an Oopsable condition in pnfs_mark_request_commit() when we're
putting a set of writes on the commit list to reschedule them after a
failed pNFS attempt.
In the Linux kernel, the following vulnerability has been resolved:
watchdog: sc520_wdt: Fix possible use-after-free in wdt_turnoff()
This module's remove path calls del_timer(). However, that function
does not wait until the timer handler finishes. This means that the
timer handler may still be running after the driver's remove function
has finished, which would result in a use-after-free.
Fix by calling del_timer_sync(), which makes sure the timer handler
has finished, and unable to re-schedule itself.
In the Linux kernel, the following vulnerability has been resolved:
watchdog: Fix possible use-after-free in wdt_startup()
This module's remove path calls del_timer(). However, that function
does not wait until the timer handler finishes. This means that the
timer handler may still be running after the driver's remove function
has finished, which would result in a use-after-free.
Fix by calling del_timer_sync(), which makes sure the timer handler
has finished, and unable to re-schedule itself.
In the Linux kernel, the following vulnerability has been resolved:
iommu/arm-smmu: Fix arm_smmu_device refcount leak in address translation
The reference counting issue happens in several exception handling paths
of arm_smmu_iova_to_phys_hard(). When those error scenarios occur, the
function forgets to decrease the refcount of "smmu" increased by
arm_smmu_rpm_get(), causing a refcount leak.
Fix this issue by jumping to "out" label when those error scenarios
occur.
In the Linux kernel, the following vulnerability has been resolved:
iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails
arm_smmu_rpm_get() invokes pm_runtime_get_sync(), which increases the
refcount of the "smmu" even though the return value is less than 0.
The reference counting issue happens in some error handling paths of
arm_smmu_rpm_get() in its caller functions. When arm_smmu_rpm_get()
fails, the caller functions forget to decrease the refcount of "smmu"
increased by arm_smmu_rpm_get(), causing a refcount leak.
Fix this issue by calling pm_runtime_resume_and_get() instead of
pm_runtime_get_sync() in arm_smmu_rpm_get(), which can keep the refcount
balanced in case of failure.
In the Linux kernel, the following vulnerability has been resolved:
scsi: iscsi: Fix conn use after free during resets
If we haven't done a unbind target call we can race where
iscsi_conn_teardown wakes up the EH thread and then frees the conn while
those threads are still accessing the conn ehwait.
We can only do one TMF per session so this just moves the TMF fields from
the conn to the session. We can then rely on the
iscsi_session_teardown->iscsi_remove_session->__iscsi_unbind_session call
to remove the target and it's devices, and know after that point there is
no device or scsi-ml callout trying to access the session.