Linux: >> Linux Kernel >> 6.6.63 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
vsock: prevent null-ptr-deref in vsock_*[has_data|has_space]
Recent reports have shown how we sometimes call vsock_*_has_data()
when a vsock socket has been de-assigned from a transport (see attached
links), but we shouldn't.
Previous commits should have solved the real problems, but we may have
more in the future, so to avoid null-ptr-deref, we can return 0
(no space, no data available) but with a warning.
This way the code should continue to run in a nearly consistent state
and have a warning that allows us to debug future problems.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-01-31
In the Linux kernel, the following vulnerability has been resolved:
iomap: avoid avoid truncating 64-bit offset to 32 bits
on 32-bit kernels, iomap_write_delalloc_scan() was inadvertently using a
32-bit position due to folio_next_index() returning an unsigned long.
This could lead to an infinite loop when writing to an xfs filesystem.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-31
In the Linux kernel, the following vulnerability has been resolved:
pmdomain: imx8mp-blk-ctrl: add missing loop break condition
Currently imx8mp_blk_ctrl_remove() will continue the for loop
until an out-of-bounds exception occurs.
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : dev_pm_domain_detach+0x8/0x48
lr : imx8mp_blk_ctrl_shutdown+0x58/0x90
sp : ffffffc084f8bbf0
x29: ffffffc084f8bbf0 x28: ffffff80daf32ac0 x27: 0000000000000000
x26: ffffffc081658d78 x25: 0000000000000001 x24: ffffffc08201b028
x23: ffffff80d0db9490 x22: ffffffc082340a78 x21: 00000000000005b0
x20: ffffff80d19bc180 x19: 000000000000000a x18: ffffffffffffffff
x17: ffffffc080a39e08 x16: ffffffc080a39c98 x15: 4f435f464f006c72
x14: 0000000000000004 x13: ffffff80d0172110 x12: 0000000000000000
x11: ffffff80d0537740 x10: ffffff80d05376c0 x9 : ffffffc0808ed2d8
x8 : ffffffc084f8bab0 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffffff80d19b9420 x4 : fffffffe03466e60 x3 : 0000000080800077
x2 : 0000000000000000 x1 : 0000000000000001 x0 : 0000000000000000
Call trace:
dev_pm_domain_detach+0x8/0x48
platform_shutdown+0x2c/0x48
device_shutdown+0x158/0x268
kernel_restart_prepare+0x40/0x58
kernel_kexec+0x58/0xe8
__do_sys_reboot+0x198/0x258
__arm64_sys_reboot+0x2c/0x40
invoke_syscall+0x5c/0x138
el0_svc_common.constprop.0+0x48/0xf0
do_el0_svc+0x24/0x38
el0_svc+0x38/0xc8
el0t_64_sync_handler+0x120/0x130
el0t_64_sync+0x190/0x198
Code: 8128c2d0 ffffffc0 aa1e03e9 d503201f
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-31
In the Linux kernel, the following vulnerability has been resolved:
dm thin: make get_first_thin use rcu-safe list first function
The documentation in rculist.h explains the absence of list_empty_rcu()
and cautions programmers against relying on a list_empty() ->
list_first() sequence in RCU safe code. This is because each of these
functions performs its own READ_ONCE() of the list head. This can lead
to a situation where the list_empty() sees a valid list entry, but the
subsequent list_first() sees a different view of list head state after a
modification.
In the case of dm-thin, this author had a production box crash from a GP
fault in the process_deferred_bios path. This function saw a valid list
head in get_first_thin() but when it subsequently dereferenced that and
turned it into a thin_c, it got the inside of the struct pool, since the
list was now empty and referring to itself. The kernel on which this
occurred printed both a warning about a refcount_t being saturated, and
a UBSAN error for an out-of-bounds cpuid access in the queued spinlock,
prior to the fault itself. When the resulting kdump was examined, it
was possible to see another thread patiently waiting in thin_dtr's
synchronize_rcu.
The thin_dtr call managed to pull the thin_c out of the active thins
list (and have it be the last entry in the active_thins list) at just
the wrong moment which lead to this crash.
Fortunately, the fix here is straight forward. Switch get_first_thin()
function to use list_first_or_null_rcu() which performs just a single
READ_ONCE() and returns NULL if the list is already empty.
This was run against the devicemapper test suite's thin-provisioning
suites for delete and suspend and no regressions were observed.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
riscv: mm: Fix the out of bound issue of vmemmap address
In sparse vmemmap model, the virtual address of vmemmap is calculated as:
((struct page *)VMEMMAP_START - (phys_ram_base >> PAGE_SHIFT)).
And the struct page's va can be calculated with an offset:
(vmemmap + (pfn)).
However, when initializing struct pages, kernel actually starts from the
first page from the same section that phys_ram_base belongs to. If the
first page's physical address is not (phys_ram_base >> PAGE_SHIFT), then
we get an va below VMEMMAP_START when calculating va for it's struct page.
For example, if phys_ram_base starts from 0x82000000 with pfn 0x82000, the
first page in the same section is actually pfn 0x80000. During
init_unavailable_range(), we will initialize struct page for pfn 0x80000
with virtual address ((struct page *)VMEMMAP_START - 0x2000), which is
below VMEMMAP_START as well as PCI_IO_END.
This commit fixes this bug by introducing a new variable
'vmemmap_start_pfn' which is aligned with memory section size and using
it to calculate vmemmap address instead of phys_ram_base.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
virtio-blk: don't keep queue frozen during system suspend
Commit 4ce6e2db00de ("virtio-blk: Ensure no requests in virtqueues before
deleting vqs.") replaces queue quiesce with queue freeze in virtio-blk's
PM callbacks. And the motivation is to drain inflight IOs before suspending.
block layer's queue freeze looks very handy, but it is also easy to cause
deadlock, such as, any attempt to call into bio_queue_enter() may run into
deadlock if the queue is frozen in current context. There are all kinds
of ->suspend() called in suspend context, so keeping queue frozen in the
whole suspend context isn't one good idea. And Marek reported lockdep
warning[1] caused by virtio-blk's freeze queue in virtblk_freeze().
[1] https://lore.kernel.org/linux-block/ca16370e-d646-4eee-b9cc-87277c89c43c@samsung.com/
Given the motivation is to drain in-flight IOs, it can be done by calling
freeze & unfreeze, meantime restore to previous behavior by keeping queue
quiesced during suspend.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (drivetemp) Fix driver producing garbage data when SCSI errors occur
scsi_execute_cmd() function can return both negative (linux codes) and
positive (scsi_cmnd result field) error codes.
Currently the driver just passes error codes of scsi_execute_cmd() to
hwmon core, which is incorrect because hwmon only checks for negative
error codes. This leads to hwmon reporting uninitialized data to
userspace in case of SCSI errors (for example if the disk drive was
disconnected).
This patch checks scsi_execute_cmd() output and returns -EIO if it's
error code is positive.
[groeck: Avoid inline variable declaration for portability]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
btrfs: avoid NULL pointer dereference if no valid extent tree
[BUG]
Syzbot reported a crash with the following call trace:
BTRFS info (device loop0): scrub: started on devid 1
BUG: kernel NULL pointer dereference, address: 0000000000000208
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206
Tainted: [O]=OOT_MODULE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022
RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]
Call Trace:
<TASK>
scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]
scrub_simple_mirror+0x175/0x260 [btrfs]
scrub_stripe+0x5d4/0x6c0 [btrfs]
scrub_chunk+0xbb/0x170 [btrfs]
scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]
btrfs_scrub_dev+0x240/0x600 [btrfs]
btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]
? do_sys_openat2+0xa5/0xf0
__x64_sys_ioctl+0x97/0xc0
do_syscall_64+0x4f/0x120
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK>
[CAUSE]
The reproducer is using a corrupted image where extent tree root is
corrupted, thus forcing to use "rescue=all,ro" mount option to mount the
image.
Then it triggered a scrub, but since scrub relies on extent tree to find
where the data/metadata extents are, scrub_find_fill_first_stripe()
relies on an non-empty extent root.
But unfortunately scrub_find_fill_first_stripe() doesn't really expect
an NULL pointer for extent root, it use extent_root to grab fs_info and
triggered a NULL pointer dereference.
[FIX]
Add an extra check for a valid extent root at the beginning of
scrub_find_fill_first_stripe().
The new error path is introduced by 42437a6386ff ("btrfs: introduce
mount option rescue=ignorebadroots"), but that's pretty old, and later
commit b979547513ff ("btrfs: scrub: introduce helper to find and fill
sector info for a scrub_stripe") changed how we do scrub.
So for kernels older than 6.6, the fix will need manual backport.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix unexpectedly changed path in ksmbd_vfs_kern_path_locked
When `ksmbd_vfs_kern_path_locked` met an error and it is not the last
entry, it will exit without restoring changed path buffer. But later this
buffer may be used as the filename for creation.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Fix variable not being completed when function returns
When cmd_alloc_index(), fails cmd_work_handler() needs
to complete ent->slotted before returning early.
Otherwise the task which issued the command may hang:
mlx5_core 0000:01:00.0: cmd_work_handler:877:(pid 3880418): failed to allocate command entry
INFO: task kworker/13:2:4055883 blocked for more than 120 seconds.
Not tainted 4.19.90-25.44.v2101.ky10.aarch64 #1
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/13:2 D 0 4055883 2 0x00000228
Workqueue: events mlx5e_tx_dim_work [mlx5_core]
Call trace:
__switch_to+0xe8/0x150
__schedule+0x2a8/0x9b8
schedule+0x2c/0x88
schedule_timeout+0x204/0x478
wait_for_common+0x154/0x250
wait_for_completion+0x28/0x38
cmd_exec+0x7a0/0xa00 [mlx5_core]
mlx5_cmd_exec+0x54/0x80 [mlx5_core]
mlx5_core_modify_cq+0x6c/0x80 [mlx5_core]
mlx5_core_modify_cq_moderation+0xa0/0xb8 [mlx5_core]
mlx5e_tx_dim_work+0x54/0x68 [mlx5_core]
process_one_work+0x1b0/0x448
worker_thread+0x54/0x468
kthread+0x134/0x138
ret_from_fork+0x10/0x18
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21