In the Linux kernel, the following vulnerability has been resolved:
ftrace: Avoid potential division by zero in function_stat_show()
Check whether denominator expression x * (x - 1) * 1000 mod {2^32, 2^64}
produce zero and skip stddev computation in that case.
For now don't care about rec->counter * rec->counter overflow because
rec->time * rec->time overflow will likely happen earlier.
In the Linux kernel, the following vulnerability has been resolved:
tracing: Fix bad hist from corrupting named_triggers list
The following commands causes a crash:
~# cd /sys/kernel/tracing/events/rcu/rcu_callback
~# echo 'hist:name=bad:keys=common_pid:onmax(bogus).save(common_pid)' > trigger
bash: echo: write error: Invalid argument
~# echo 'hist:name=bad:keys=common_pid' > trigger
Because the following occurs:
event_trigger_write() {
trigger_process_regex() {
event_hist_trigger_parse() {
data = event_trigger_alloc(..);
event_trigger_register(.., data) {
cmd_ops->reg(.., data, ..) [hist_register_trigger()] {
data->ops->init() [event_hist_trigger_init()] {
save_named_trigger(name, data) {
list_add(&data->named_list, &named_triggers);
}
}
}
}
ret = create_actions(); (return -EINVAL)
if (ret)
goto out_unreg;
[..]
ret = hist_trigger_enable(data, ...) {
list_add_tail_rcu(&data->list, &file->triggers); <<<---- SKIPPED!!! (this is important!)
[..]
out_unreg:
event_hist_unregister(.., data) {
cmd_ops->unreg(.., data, ..) [hist_unregister_trigger()] {
list_for_each_entry(iter, &file->triggers, list) {
if (!hist_trigger_match(data, iter, named_data, false)) <- never matches
continue;
[..]
test = iter;
}
if (test && test->ops->free) <<<-- test is NULL
test->ops->free(test) [event_hist_trigger_free()] {
[..]
if (data->name)
del_named_trigger(data) {
list_del(&data->named_list); <<<<-- NEVER gets removed!
}
}
}
}
[..]
kfree(data); <<<-- frees item but it is still on list
The next time a hist with name is registered, it causes an u-a-f bug and
the kernel can crash.
Move the code around such that if event_trigger_register() succeeds, the
next thing called is hist_trigger_enable() which adds it to the list.
A bunch of actions is called if get_named_trigger_data() returns false.
But that doesn't need to be called after event_trigger_register(), so it
can be moved up, allowing event_trigger_register() to be called just
before hist_trigger_enable() keeping them together and allowing the
file->triggers to be properly populated.
In the Linux kernel, the following vulnerability has been resolved:
caif_virtio: fix wrong pointer check in cfv_probe()
del_vqs() frees virtqueues, therefore cfv->vq_tx pointer should be checked
for NULL before calling it, not cfv->vdev. Also the current implementation
is redundant because the pointer cfv->vdev is dereferenced before it is
checked for NULL.
Fix this by checking cfv->vq_tx for NULL instead of cfv->vdev before
calling del_vqs().
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: limit printed string from FW file
There's no guarantee here that the file is always with a
NUL-termination, so reading the string may read beyond the
end of the TLV. If that's the last TLV in the file, it can
perhaps even read beyond the end of the file buffer.
Fix that by limiting the print format to the size of the
buffer we have.
In the Linux kernel, the following vulnerability has been resolved:
net: enetc: VFs do not support HWTSTAMP_TX_ONESTEP_SYNC
Actually ENETC VFs do not support HWTSTAMP_TX_ONESTEP_SYNC because only
ENETC PF can access PMa_SINGLE_STEP registers. And there will be a crash
if VFs are used to test one-step timestamp, the crash log as follows.
[ 129.110909] Unable to handle kernel paging request at virtual address 00000000000080c0
[ 129.287769] Call trace:
[ 129.290219] enetc_port_mac_wr+0x30/0xec (P)
[ 129.294504] enetc_start_xmit+0xda4/0xe74
[ 129.298525] enetc_xmit+0x70/0xec
[ 129.301848] dev_hard_start_xmit+0x98/0x118
In the Linux kernel, the following vulnerability has been resolved:
thermal: core: call put_device() only after device_register() fails
put_device() shouldn't be called before a prior call to
device_register(). __thermal_cooling_device_register() doesn't follow
that properly and needs fixing. Also
thermal_cooling_device_destroy_sysfs() is getting called unnecessarily
on few error paths.
Fix all this by placing the calls at the right place.
Based on initial work done by Caleb Connolly.
In the Linux kernel, the following vulnerability has been resolved:
net: fix UaF in netns ops registration error path
If net_assign_generic() fails, the current error path in ops_init() tries
to clear the gen pointer slot. Anyway, in such error path, the gen pointer
itself has not been modified yet, and the existing and accessed one is
smaller than the accessed index, causing an out-of-bounds error:
BUG: KASAN: slab-out-of-bounds in ops_init+0x2de/0x320
Write of size 8 at addr ffff888109124978 by task modprobe/1018
CPU: 2 PID: 1018 Comm: modprobe Not tainted 6.2.0-rc2.mptcp_ae5ac65fbed5+ #1641
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.1-2.fc37 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x6a/0x9f
print_address_description.constprop.0+0x86/0x2b5
print_report+0x11b/0x1fb
kasan_report+0x87/0xc0
ops_init+0x2de/0x320
register_pernet_operations+0x2e4/0x750
register_pernet_subsys+0x24/0x40
tcf_register_action+0x9f/0x560
do_one_initcall+0xf9/0x570
do_init_module+0x190/0x650
load_module+0x1fa5/0x23c0
__do_sys_finit_module+0x10d/0x1b0
do_syscall_64+0x58/0x80
entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f42518f778d
Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48
89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 73 01 c3 48 8b 0d cb 56 2c 00 f7 d8 64 89 01 48
RSP: 002b:00007fff96869688 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 00005568ef7f7c90 RCX: 00007f42518f778d
RDX: 0000000000000000 RSI: 00005568ef41d796 RDI: 0000000000000003
RBP: 00005568ef41d796 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000
R13: 00005568ef7f7d30 R14: 0000000000040000 R15: 0000000000000000
</TASK>
This change addresses the issue by skipping the gen pointer
de-reference in the mentioned error-path.
Found by code inspection and verified with explicit error injection
on a kasan-enabled kernel.
In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: ipc4-mtrace: prevent underflow in sof_ipc4_priority_mask_dfs_write()
The "id" comes from the user. Change the type to unsigned to prevent
an array underflow.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda/via: Avoid potential array out-of-bound in add_secret_dac_path()
snd_hda_get_connections() can return a negative error code.
It may lead to accessing 'conn' array at a negative index.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
firewire: fix memory leak for payload of request subaction to IEC 61883-1 FCP region
This patch is fix for Linux kernel v2.6.33 or later.
For request subaction to IEC 61883-1 FCP region, Linux FireWire subsystem
have had an issue of use-after-free. The subsystem allows multiple
user space listeners to the region, while data of the payload was likely
released before the listeners execute read(2) to access to it for copying
to user space.
The issue was fixed by a commit 281e20323ab7 ("firewire: core: fix
use-after-free regression in FCP handler"). The object of payload is
duplicated in kernel space for each listener. When the listener executes
ioctl(2) with FW_CDEV_IOC_SEND_RESPONSE request, the object is going to
be released.
However, it causes memory leak since the commit relies on call of
release_request() in drivers/firewire/core-cdev.c. Against the
expectation, the function is never called due to the design of
release_client_resource(). The function delegates release task
to caller when called with non-NULL fourth argument. The implementation
of ioctl_send_response() is the case. It should release the object
explicitly.
This commit fixes the bug.