Linux: >> Linux Kernel >> 5.4.43 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: don't delete error page from pagecache
This change is very similar to the change that was made for shmem [1], and
it solves the same problem but for HugeTLBFS instead.
Currently, when poison is found in a HugeTLB page, the page is removed
from the page cache. That means that attempting to map or read that
hugepage in the future will result in a new hugepage being allocated
instead of notifying the user that the page was poisoned. As [1] states,
this is effectively memory corruption.
The fix is to leave the page in the page cache. If the user attempts to
use a poisoned HugeTLB page with a syscall, the syscall will fail with
EIO, the same error code that shmem uses. For attempts to map the page,
the thread will get a BUS_MCEERR_AR SIGBUS.
[1]: commit a76054266661 ("mm: shmem: don't truncate page if memory failure happens")
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
drm/scheduler: fix fence ref counting
We leaked dependency fences when processes were beeing killed.
Additional to that grab a reference to the last scheduled fence.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
btrfs: zoned: initialize device's zone info for seeding
When performing seeding on a zoned filesystem it is necessary to
initialize each zoned device's btrfs_zoned_device_info structure,
otherwise mounting the filesystem will cause a NULL pointer dereference.
This was uncovered by fstests' testcase btrfs/163.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
pinctrl: devicetree: fix null pointer dereferencing in pinctrl_dt_to_map
Here is the BUG report by KASAN about null pointer dereference:
BUG: KASAN: null-ptr-deref in strcmp+0x2e/0x50
Read of size 1 at addr 0000000000000000 by task python3/2640
Call Trace:
strcmp
__of_find_property
of_find_property
pinctrl_dt_to_map
kasprintf() would return NULL pointer when kmalloc() fail to allocate.
So directly return ENOMEM, if kasprintf() return NULL pointer.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix use-after-free bug of ns_writer on remount
If a nilfs2 filesystem is downgraded to read-only due to metadata
corruption on disk and is remounted read/write, or if emergency read-only
remount is performed, detaching a log writer and synchronizing the
filesystem can be done at the same time.
In these cases, use-after-free of the log writer (hereinafter
nilfs->ns_writer) can happen as shown in the scenario below:
Task1 Task2
-------------------------------- ------------------------------
nilfs_construct_segment
nilfs_segctor_sync
init_wait
init_waitqueue_entry
add_wait_queue
schedule
nilfs_remount (R/W remount case)
nilfs_attach_log_writer
nilfs_detach_log_writer
nilfs_segctor_destroy
kfree
finish_wait
_raw_spin_lock_irqsave
__raw_spin_lock_irqsave
do_raw_spin_lock
debug_spin_lock_before <-- use-after-free
While Task1 is sleeping, nilfs->ns_writer is freed by Task2. After Task1
waked up, Task1 accesses nilfs->ns_writer which is already freed. This
scenario diagram is based on the Shigeru Yoshida's post [1].
This patch fixes the issue by not detaching nilfs->ns_writer on remount so
that this UAF race doesn't happen. Along with this change, this patch
also inserts a few necessary read-only checks with superblock instance
where only the ns_writer pointer was used to check if the filesystem is
read-only.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: fix potential memleak in 'add_widget_node'
As 'kobject_add' may allocated memory for 'kobject->name' when return error.
And in this function, if call 'kobject_add' failed didn't free kobject.
So call 'kobject_put' to recycling resources.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
mISDN: fix possible memory leak in mISDN_dsp_element_register()
Afer commit 1fa5ae857bb1 ("driver core: get rid of struct device's
bus_id string array"), the name of device is allocated dynamically,
use put_device() to give up the reference, so that the name can be
freed in kobject_cleanup() when the refcount is 0.
The 'entry' is going to be freed in mISDN_dsp_dev_release(), so the
kfree() is removed. list_del() is called in mISDN_dsp_dev_release(),
so it need be initialized.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix connections leak when tlink setup failed
If the tlink setup failed, lost to put the connections, then
the module refcnt leak since the cifsd kthread not exit.
Also leak the fscache info, and for next mount with fsc, it will
print the follow errors:
CIFS: Cache volume key already in use (cifs,127.0.0.1:445,TEST)
Let's check the result of tlink setup, and do some cleanup.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ata: libata-transport: fix error handling in ata_tdev_add()
In ata_tdev_add(), the return value of transport_add_device() is
not checked. As a result, it causes null-ptr-deref while removing
the module, because transport_remove_device() is called to remove
the device that was not added.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 13 PID: 13603 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #36
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x3a0
lr : device_del+0x44/0x3a0
Call trace:
device_del+0x48/0x3a0
attribute_container_class_device_del+0x28/0x40
transport_remove_classdev+0x60/0x7c
attribute_container_device_trigger+0x118/0x120
transport_remove_device+0x20/0x30
ata_tdev_delete+0x24/0x50 [libata]
ata_tlink_delete+0x40/0xa0 [libata]
ata_tport_delete+0x2c/0x60 [libata]
ata_port_detach+0x148/0x1b0 [libata]
ata_pci_remove_one+0x50/0x80 [libata]
ahci_remove_one+0x4c/0x8c [ahci]
Fix this by checking and handling return value of transport_add_device()
in ata_tdev_add(). In the error path, device_del() is called to delete
the device which was added earlier in this function, and ata_tdev_free()
is called to free ata_dev.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ata: libata-transport: fix error handling in ata_tlink_add()
In ata_tlink_add(), the return value of transport_add_device() is
not checked. As a result, it causes null-ptr-deref while removing
the module, because transport_remove_device() is called to remove
the device that was not added.
Unable to handle kernel NULL pointer dereference at virtual address 00000000000000d0
CPU: 33 PID: 13850 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc3+ #12
pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x48/0x39c
lr : device_del+0x44/0x39c
Call trace:
device_del+0x48/0x39c
attribute_container_class_device_del+0x28/0x40
transport_remove_classdev+0x60/0x7c
attribute_container_device_trigger+0x118/0x120
transport_remove_device+0x20/0x30
ata_tlink_delete+0x88/0xb0 [libata]
ata_tport_delete+0x2c/0x60 [libata]
ata_port_detach+0x148/0x1b0 [libata]
ata_pci_remove_one+0x50/0x80 [libata]
ahci_remove_one+0x4c/0x8c [ahci]
Fix this by checking and handling return value of transport_add_device()
in ata_tlink_add().
CVSS Score
5.5
EPSS Score
0.001
Published
2025-05-01