Linux: >> Linux Kernel >> 6.1.124 Security Vulnerabilities
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:
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
0.0
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
In the Linux kernel, the following vulnerability has been resolved:
exfat: fix the infinite loop in exfat_readdir()
If the file system is corrupted so that a cluster is linked to
itself in the cluster chain, and there is an unused directory
entry in the cluster, 'dentry' will not be incremented, causing
condition 'dentry < max_dentries' unable to prevent an infinite
loop.
This infinite loop causes s_lock not to be released, and other
tasks will hang, such as exfat_sync_fs().
This commit stops traversing the cluster chain when there is unused
directory entry in the cluster to avoid this infinite loop.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
riscv: Fix sleeping in invalid context in die()
die() can be called in exception handler, and therefore cannot sleep.
However, die() takes spinlock_t which can sleep with PREEMPT_RT enabled.
That causes the following warning:
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 285, name: mutex
preempt_count: 110001, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 UID: 0 PID: 285 Comm: mutex Not tainted 6.12.0-rc7-00022-ge19049cf7d56-dirty #234
Hardware name: riscv-virtio,qemu (DT)
Call Trace:
dump_backtrace+0x1c/0x24
show_stack+0x2c/0x38
dump_stack_lvl+0x5a/0x72
dump_stack+0x14/0x1c
__might_resched+0x130/0x13a
rt_spin_lock+0x2a/0x5c
die+0x24/0x112
do_trap_insn_illegal+0xa0/0xea
_new_vmalloc_restore_context_a0+0xcc/0xd8
Oops - illegal instruction [#1]
Switch to use raw_spinlock_t, which does not sleep even with PREEMPT_RT
enabled.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
io_uring/eventfd: ensure io_eventfd_signal() defers another RCU period
io_eventfd_do_signal() is invoked from an RCU callback, but when
dropping the reference to the io_ev_fd, it calls io_eventfd_free()
directly if the refcount drops to zero. This isn't correct, as any
potential freeing of the io_ev_fd should be deferred another RCU grace
period.
Just call io_eventfd_put() rather than open-code the dec-and-test and
free, which will correctly defer it another RCU grace period.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-01-20
In the Linux kernel, the following vulnerability has been resolved:
dm array: fix releasing a faulty array block twice in dm_array_cursor_end
When dm_bm_read_lock() fails due to locking or checksum errors, it
releases the faulty block implicitly while leaving an invalid output
pointer behind. The caller of dm_bm_read_lock() should not operate on
this invalid dm_block pointer, or it will lead to undefined result.
For example, the dm_array_cursor incorrectly caches the invalid pointer
on reading a faulty array block, causing a double release in
dm_array_cursor_end(), then hitting the BUG_ON in dm-bufio cache_put().
Reproduce steps:
1. initialize a cache device
dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc $262144"
dd if=/dev/zero of=/dev/mapper/cmeta bs=4k count=1
dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"
2. wipe the second array block offline
dmsteup remove cache cmeta cdata corig
mapping_root=$(dd if=/dev/sdc bs=1c count=8 skip=192 \
2>/dev/null | hexdump -e '1/8 "%u\n"')
ablock=$(dd if=/dev/sdc bs=1c count=8 skip=$((4096*mapping_root+2056)) \
2>/dev/null | hexdump -e '1/8 "%u\n"')
dd if=/dev/zero of=/dev/sdc bs=4k count=1 seek=$ablock
3. try reopen the cache device
dmsetup create cmeta --table "0 8192 linear /dev/sdc 0"
dmsetup create cdata --table "0 65536 linear /dev/sdc 8192"
dmsetup create corig --table "0 524288 linear /dev/sdc $262144"
dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \
/dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0"
Kernel logs:
(snip)
device-mapper: array: array_block_check failed: blocknr 0 != wanted 10
device-mapper: block manager: array validator check failed for block 10
device-mapper: array: get_ablock failed
device-mapper: cache metadata: dm_array_cursor_next for mapping failed
------------[ cut here ]------------
kernel BUG at drivers/md/dm-bufio.c:638!
Fix by setting the cached block pointer to NULL on errors.
In addition to the reproducer described above, this fix can be
verified using the "array_cursor/damaged" test in dm-unit:
dm-unit run /pdata/array_cursor/damaged --kernel-dir <KERNEL_DIR>
CVSS Score
7.1
EPSS Score
0.0
Published
2025-01-19
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/display: Add check for granularity in dml ceil/floor helpers
[Why]
Wrapper functions for dcn_bw_ceil2() and dcn_bw_floor2()
should check for granularity is non zero to avoid assert and
divide-by-zero error in dcn_bw_ functions.
[How]
Add check for granularity 0.
(cherry picked from commit f6e09701c3eb2ccb8cb0518e0b67f1c69742a4ec)
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-19