Security Vulnerabilities - CVEs Published In June 2024
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix potential hang in nilfs_detach_log_writer()
Syzbot has reported a potential hang in nilfs_detach_log_writer() called
during nilfs2 unmount.
Analysis revealed that this is because nilfs_segctor_sync(), which
synchronizes with the log writer thread, can be called after
nilfs_segctor_destroy() terminates that thread, as shown in the call trace
below:
nilfs_detach_log_writer
nilfs_segctor_destroy
nilfs_segctor_kill_thread --> Shut down log writer thread
flush_work
nilfs_iput_work_func
nilfs_dispose_list
iput
nilfs_evict_inode
nilfs_transaction_commit
nilfs_construct_segment (if inode needs sync)
nilfs_segctor_sync --> Attempt to synchronize with
log writer thread
*** DEADLOCK ***
Fix this issue by changing nilfs_segctor_sync() so that the log writer
thread returns normally without synchronizing after it terminates, and by
forcing tasks that are already waiting to complete once after the thread
terminates.
The skipped inode metadata flushout will then be processed together in the
subsequent cleanup work in nilfs_segctor_destroy().
CVSS Score
5.3
EPSS Score
0.001
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix use-after-free of timer for log writer thread
Patch series "nilfs2: fix log writer related issues".
This bug fix series covers three nilfs2 log writer-related issues,
including a timer use-after-free issue and potential deadlock issue on
unmount, and a potential freeze issue in event synchronization found
during their analysis. Details are described in each commit log.
This patch (of 3):
A use-after-free issue has been reported regarding the timer sc_timer on
the nilfs_sc_info structure.
The problem is that even though it is used to wake up a sleeping log
writer thread, sc_timer is not shut down until the nilfs_sc_info structure
is about to be freed, and is used regardless of the thread's lifetime.
Fix this issue by limiting the use of sc_timer only while the log writer
thread is alive.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
net: ti: icssg_prueth: Fix NULL pointer dereference in prueth_probe()
In the prueth_probe() function, if one of the calls to emac_phy_connect()
fails due to of_phy_connect() returning NULL, then the subsequent call to
phy_attached_info() will dereference a NULL pointer.
Check the return code of emac_phy_connect and fail cleanly if there is an
error.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
speakup: Fix sizeof() vs ARRAY_SIZE() bug
The "buf" pointer is an array of u16 values. This code should be
using ARRAY_SIZE() (which is 256) instead of sizeof() (which is 512),
otherwise it can the still got out of bounds.
CVSS Score
5.3
EPSS Score
0.001
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
ftrace: Fix possible use-after-free issue in ftrace_location()
KASAN reports a bug:
BUG: KASAN: use-after-free in ftrace_location+0x90/0x120
Read of size 8 at addr ffff888141d40010 by task insmod/424
CPU: 8 PID: 424 Comm: insmod Tainted: G W 6.9.0-rc2+
[...]
Call Trace:
<TASK>
dump_stack_lvl+0x68/0xa0
print_report+0xcf/0x610
kasan_report+0xb5/0xe0
ftrace_location+0x90/0x120
register_kprobe+0x14b/0xa40
kprobe_init+0x2d/0xff0 [kprobe_example]
do_one_initcall+0x8f/0x2d0
do_init_module+0x13a/0x3c0
load_module+0x3082/0x33d0
init_module_from_file+0xd2/0x130
__x64_sys_finit_module+0x306/0x440
do_syscall_64+0x68/0x140
entry_SYSCALL_64_after_hwframe+0x71/0x79
The root cause is that, in lookup_rec(), ftrace record of some address
is being searched in ftrace pages of some module, but those ftrace pages
at the same time is being freed in ftrace_release_mod() as the
corresponding module is being deleted:
CPU1 | CPU2
register_kprobes() { | delete_module() {
check_kprobe_address_safe() { |
arch_check_ftrace_location() { |
ftrace_location() { |
lookup_rec() // USE! | ftrace_release_mod() // Free!
To fix this issue:
1. Hold rcu lock as accessing ftrace pages in ftrace_location_range();
2. Use ftrace_location_range() instead of lookup_rec() in
ftrace_location();
3. Call synchronize_rcu() before freeing any ftrace pages both in
ftrace_process_locs()/ftrace_release_mod()/ftrace_free_mem().
CVSS Score
7.8
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
drivers/perf: hisi_pcie: Fix out-of-bound access when valid event group
The perf tool allows users to create event groups through following
cmd [1], but the driver does not check whether the array index is out of
bounds when writing data to the event_group array. If the number of events
in an event_group is greater than HISI_PCIE_MAX_COUNTERS, the memory write
overflow of event_group array occurs.
Add array index check to fix the possible array out of bounds violation,
and return directly when write new events are written to array bounds.
There are 9 different events in an event_group.
[1] perf stat -e '{pmu/event1/, ... ,pmu/event9/}'
CVSS Score
7.8
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix potential glock use-after-free on unmount
When a DLM lockspace is released and there ares still locks in that
lockspace, DLM will unlock those locks automatically. Commit
fb6791d100d1b started exploiting this behavior to speed up filesystem
unmount: gfs2 would simply free glocks it didn't want to unlock and then
release the lockspace. This didn't take the bast callbacks for
asynchronous lock contention notifications into account, which remain
active until until a lock is unlocked or its lockspace is released.
To prevent those callbacks from accessing deallocated objects, put the
glocks that should not be unlocked on the sd_dead_glocks list, release
the lockspace, and only then free those glocks.
As an additional measure, ignore unexpected ast and bast callbacks if
the receiving glock is dead.
CVSS Score
7.8
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
thermal/drivers/tsens: Fix null pointer dereference
compute_intercept_slope() is called from calibrate_8960() (in tsens-8960.c)
as compute_intercept_slope(priv, p1, NULL, ONE_PT_CALIB) which lead to null
pointer dereference (if DEBUG or DYNAMIC_DEBUG set).
Fix this bug by adding null pointer check.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
cppc_cpufreq: Fix possible null pointer dereference
cppc_cpufreq_get_rate() and hisi_cppc_cpufreq_get_rate() can be called from
different places with various parameters. So cpufreq_cpu_get() can return
null as 'policy' in some circumstances.
Fix this bug by adding null return check.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
7.5
EPSS Score
0.0
Published
2024-06-19
In the Linux kernel, the following vulnerability has been resolved:
libbpf: Prevent null-pointer dereference when prog to load has no BTF
In bpf_objec_load_prog(), there's no guarantee that obj->btf is non-NULL
when passing it to btf__fd(), and this function does not perform any
check before dereferencing its argument (as bpf_object__btf_fd() used to
do). As a consequence, we get segmentation fault errors in bpftool (for
example) when trying to load programs that come without BTF information.
v2: Keep btf__fd() in the fix instead of reverting to bpf_object__btf_fd().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-06-19