Linux: >> Linux Kernel >> 6.1.52 Security Vulnerabilities
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:
net/sctp: Prevent autoclose integer overflow in sctp_association_init()
While by default max_autoclose equals to INT_MAX / HZ, one may set
net.sctp.max_autoclose to UINT_MAX. There is code in
sctp_association_init() that can consequently trigger overflow.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-21
In the Linux kernel, the following vulnerability has been resolved:
selinux: ignore unknown extended permissions
When evaluating extended permissions, ignore unknown permissions instead
of calling BUG(). This commit ensures that future permissions can be
added without interfering with older kernels.
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:
netfilter: nf_tables: adapt set backend to use GC transaction API
Use the GC transaction API to replace the old and buggy gc API and the
busy mark approach.
No set elements are removed from async garbage collection anymore,
instead the _DEAD bit is set on so the set element is not visible from
lookup path anymore. Async GC enqueues transaction work that might be
aborted and retried later.
rbtree and pipapo set backends does not set on the _DEAD bit from the
sync GC path since this runs in control plane path where mutex is held.
In this case, set elements are deactivated, removed and then released
via RCU callback, sync GC never fails.
CVSS Score
5.5
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
In the Linux kernel, the following vulnerability has been resolved:
fs: relax assertions on failure to encode file handles
Encoding file handles is usually performed by a filesystem >encode_fh()
method that may fail for various reasons.
The legacy users of exportfs_encode_fh(), namely, nfsd and
name_to_handle_at(2) syscall are ready to cope with the possibility
of failure to encode a file handle.
There are a few other users of exportfs_encode_{fh,fid}() that
currently have a WARN_ON() assertion when ->encode_fh() fails.
Relax those assertions because they are wrong.
The second linked bug report states commit 16aac5ad1fa9 ("ovl: support
encoding non-decodable file handles") in v6.6 as the regressing commit,
but this is not accurate.
The aforementioned commit only increases the chances of the assertion
and allows triggering the assertion with the reproducer using overlayfs,
inotify and drop_caches.
Triggering this assertion was always possible with other filesystems and
other reasons of ->encode_fh() failures and more particularly, it was
also possible with the exact same reproducer using overlayfs that is
mounted with options index=on,nfs_export=on also on kernels < v6.6.
Therefore, I am not listing the aforementioned commit as a Fixes commit.
Backport hint: this patch will have a trivial conflict applying to
v6.6.y, and other trivial conflicts applying to stable kernels < v6.6.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-01-19
In the Linux kernel, the following vulnerability has been resolved:
iio: light: vcnl4035: fix information leak in triggered buffer
The 'buffer' local array is used to push data to userspace from a
triggered buffer, but it does not set an initial value for the single
data element, which is an u16 aligned to 8 bytes. That leaves at least
4 bytes uninitialized even after writing an integer value with
regmap_read().
Initialize the array to zero before using it to avoid pushing
uninitialized information to userspace.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-01-19