Security Vulnerabilities
- CVEs Published In January 2025
In the Linux kernel, the following vulnerability has been resolved:
arm64: ptrace: fix partial SETREGSET for NT_ARM_FPMR
Currently fpmr_set() doesn't initialize the temporary 'fpmr' variable,
and a SETREGSET call with a length of zero will leave this
uninitialized. Consequently an arbitrary value will be written back to
target->thread.uw.fpmr, potentially leaking up to 64 bits of memory from
the kernel stack. The read is limited to a specific slot on the stack,
and the issue does not provide a write mechanism.
Fix this by initializing the temporary value before copying the regset
from userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,
NT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing
contents of FPMR will be retained.
Before this patch:
| # ./fpmr-test
| Attempting to write NT_ARM_FPMR::fpmr = 0x900d900d900d900d
| SETREGSET(nt=0x40e, len=8) wrote 8 bytes
|
| Attempting to read NT_ARM_FPMR::fpmr
| GETREGSET(nt=0x40e, len=8) read 8 bytes
| Read NT_ARM_FPMR::fpmr = 0x900d900d900d900d
|
| Attempting to write NT_ARM_FPMR (zero length)
| SETREGSET(nt=0x40e, len=0) wrote 0 bytes
|
| Attempting to read NT_ARM_FPMR::fpmr
| GETREGSET(nt=0x40e, len=8) read 8 bytes
| Read NT_ARM_FPMR::fpmr = 0xffff800083963d50
After this patch:
| # ./fpmr-test
| Attempting to write NT_ARM_FPMR::fpmr = 0x900d900d900d900d
| SETREGSET(nt=0x40e, len=8) wrote 8 bytes
|
| Attempting to read NT_ARM_FPMR::fpmr
| GETREGSET(nt=0x40e, len=8) read 8 bytes
| Read NT_ARM_FPMR::fpmr = 0x900d900d900d900d
|
| Attempting to write NT_ARM_FPMR (zero length)
| SETREGSET(nt=0x40e, len=0) wrote 0 bytes
|
| Attempting to read NT_ARM_FPMR::fpmr
| GETREGSET(nt=0x40e, len=8) read 8 bytes
| Read NT_ARM_FPMR::fpmr = 0x900d900d900d900d
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: iso: Always release hdev at the end of iso_listen_bis
Since hci_get_route holds the device before returning, the hdev
should be released with hci_dev_put at the end of iso_listen_bis
even if the function returns with an error.
In the Linux kernel, the following vulnerability has been resolved:
ASoC: Intel: sof_sdw: Add space for a terminator into DAIs array
The code uses the initialised member of the asoc_sdw_dailink struct to
determine if a member of the array is in use. However in the case the
array is completely full this will lead to an access 1 past the end of
the array, expand the array by one entry to include a space for a
terminator.
In the Linux kernel, the following vulnerability has been resolved:
Revert "readahead: properly shorten readahead when falling back to do_page_cache_ra()"
This reverts commit 7c877586da3178974a8a94577b6045a48377ff25.
Anders and Philippe have reported that recent kernels occasionally hang
when used with NFS in readahead code. The problem has been bisected to
7c877586da3 ("readahead: properly shorten readahead when falling back to
do_page_cache_ra()"). The cause of the problem is that ra->size can be
shrunk by read_pages() call and subsequently we end up calling
do_page_cache_ra() with negative (read huge positive) number of pages.
Let's revert 7c877586da3 for now until we can find a proper way how the
logic in read_pages() and page_cache_ra_order() can coexist. This can
lead to reduced readahead throughput due to readahead window confusion but
that's better than outright hangs.
In the Linux kernel, the following vulnerability has been resolved:
virtio-net: fix overflow inside virtnet_rq_alloc
When the frag just got a page, then may lead to regression on VM.
Specially if the sysctl net.core.high_order_alloc_disable value is 1,
then the frag always get a page when do refill.
Which could see reliable crashes or scp failure (scp a file 100M in size
to VM).
The issue is that the virtnet_rq_dma takes up 16 bytes at the beginning
of a new frag. When the frag size is larger than PAGE_SIZE,
everything is fine. However, if the frag is only one page and the
total size of the buffer and virtnet_rq_dma is larger than one page, an
overflow may occur.
The commit f9dac92ba908 ("virtio_ring: enable premapped mode whatever
use_dma_api") introduced this problem. And we reverted some commits to
fix this in last linux version. Now we try to enable it and fix this
bug directly.
Here, when the frag size is not enough, we reduce the buffer len to fix
this problem.
In the Linux kernel, the following vulnerability has been resolved:
s390/cpum_sf: Handle CPU hotplug remove during sampling
CPU hotplug remove handling triggers the following function
call sequence:
CPUHP_AP_PERF_S390_SF_ONLINE --> s390_pmu_sf_offline_cpu()
...
CPUHP_AP_PERF_ONLINE --> perf_event_exit_cpu()
The s390 CPUMF sampling CPU hotplug handler invokes:
s390_pmu_sf_offline_cpu()
+--> cpusf_pmu_setup()
+--> setup_pmc_cpu()
+--> deallocate_buffers()
This function de-allocates all sampling data buffers (SDBs) allocated
for that CPU at event initialization. It also clears the
PMU_F_RESERVED bit. The CPU is gone and can not be sampled.
With the event still being active on the removed CPU, the CPU event
hotplug support in kernel performance subsystem triggers the
following function calls on the removed CPU:
perf_event_exit_cpu()
+--> perf_event_exit_cpu_context()
+--> __perf_event_exit_context()
+--> __perf_remove_from_context()
+--> event_sched_out()
+--> cpumsf_pmu_del()
+--> cpumsf_pmu_stop()
+--> hw_perf_event_update()
to stop and remove the event. During removal of the event, the
sampling device driver tries to read out the remaining samples from
the sample data buffers (SDBs). But they have already been freed
(and may have been re-assigned). This may lead to a use after free
situation in which case the samples are most likely invalid. In the
best case the memory has not been reassigned and still contains
valid data.
Remedy this situation and check if the CPU is still in reserved
state (bit PMU_F_RESERVED set). In this case the SDBs have not been
released an contain valid data. This is always the case when
the event is removed (and no CPU hotplug off occured).
If the PMU_F_RESERVED bit is not set, the SDB buffers are gone.
In the Linux kernel, the following vulnerability has been resolved:
jffs2: Prevent rtime decompress memory corruption
The rtime decompression routine does not fully check bounds during the
entirety of the decompression pass and can corrupt memory outside the
decompression buffer if the compressed data is corrupted. This adds the
required check to prevent this failure mode.
In the Linux kernel, the following vulnerability has been resolved:
scsi: ufs: pltfrm: Dellocate HBA during ufshcd_pltfrm_remove()
This will ensure that the scsi host is cleaned up properly using
scsi_host_dev_release(). Otherwise, it may lead to memory leaks.
In the Linux kernel, the following vulnerability has been resolved:
arm64: ptrace: fix partial SETREGSET for NT_ARM_TAGGED_ADDR_CTRL
Currently tagged_addr_ctrl_set() doesn't initialize the temporary 'ctrl'
variable, and a SETREGSET call with a length of zero will leave this
uninitialized. Consequently tagged_addr_ctrl_set() will consume an
arbitrary value, potentially leaking up to 64 bits of memory from the
kernel stack. The read is limited to a specific slot on the stack, and
the issue does not provide a write mechanism.
As set_tagged_addr_ctrl() only accepts values where bits [63:4] zero and
rejects other values, a partial SETREGSET attempt will randomly succeed
or fail depending on the value of the uninitialized value, and the
exposure is significantly limited.
Fix this by initializing the temporary value before copying the regset
from userspace, as for other regsets (e.g. NT_PRSTATUS, NT_PRFPREG,
NT_ARM_SYSTEM_CALL). In the case of a zero-length write, the existing
value of the tagged address ctrl will be retained.
The NT_ARM_TAGGED_ADDR_CTRL regset is only visible in the
user_aarch64_view used by a native AArch64 task to manipulate another
native AArch64 task. As get_tagged_addr_ctrl() only returns an error
value when called for a compat task, tagged_addr_ctrl_get() and
tagged_addr_ctrl_set() should never observe an error value from
get_tagged_addr_ctrl(). Add a WARN_ON_ONCE() to both to indicate that
such an error would be unexpected, and error handlnig is not missing in
either case.
In the Linux kernel, the following vulnerability has been resolved:
block: RCU protect disk->conv_zones_bitmap
Ensure that a disk revalidation changing the conventional zones bitmap
of a disk does not cause invalid memory references when using the
disk_zone_is_conv() helper by RCU protecting the disk->conv_zones_bitmap
pointer.
disk_zone_is_conv() is modified to operate under the RCU read lock and
the function disk_set_conv_zones_bitmap() is added to update a disk
conv_zones_bitmap pointer using rcu_replace_pointer() with the disk
zone_wplugs_lock spinlock held.
disk_free_zone_resources() is modified to call
disk_update_zone_resources() with a NULL bitmap pointer to free the disk
conv_zones_bitmap. disk_set_conv_zones_bitmap() is also used in
disk_update_zone_resources() to set the new (revalidated) bitmap and
free the old one.