Linux: >> Linux Kernel >> 5.6.19 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
tty: goldfish: Use tty_port_destroy() to destroy port
In goldfish_tty_probe(), the port initialized through tty_port_init()
should be destroyed in error paths.In goldfish_tty_remove(), qtty->port
also should be destroyed or else might leak resources.
Fix the above by calling tty_port_destroy().
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
ftrace: Clean up hash direct_functions on register failures
We see the following GPF when register_ftrace_direct fails:
[ ] general protection fault, probably for non-canonical address \
0x200000000000010: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC PTI
[...]
[ ] RIP: 0010:ftrace_find_rec_direct+0x53/0x70
[ ] Code: 48 c1 e0 03 48 03 42 08 48 8b 10 31 c0 48 85 d2 74 [...]
[ ] RSP: 0018:ffffc9000138bc10 EFLAGS: 00010206
[ ] RAX: 0000000000000000 RBX: ffffffff813e0df0 RCX: 000000000000003b
[ ] RDX: 0200000000000000 RSI: 000000000000000c RDI: ffffffff813e0df0
[ ] RBP: ffffffffa00a3000 R08: ffffffff81180ce0 R09: 0000000000000001
[ ] R10: ffffc9000138bc18 R11: 0000000000000001 R12: ffffffff813e0df0
[ ] R13: ffffffff813e0df0 R14: ffff888171b56400 R15: 0000000000000000
[ ] FS: 00007fa9420c7780(0000) GS:ffff888ff6a00000(0000) knlGS:000000000
[ ] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ ] CR2: 000000000770d000 CR3: 0000000107d50003 CR4: 0000000000370ee0
[ ] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ ] Call Trace:
[ ] <TASK>
[ ] register_ftrace_direct+0x54/0x290
[ ] ? render_sigset_t+0xa0/0xa0
[ ] bpf_trampoline_update+0x3f5/0x4a0
[ ] ? 0xffffffffa00a3000
[ ] bpf_trampoline_link_prog+0xa9/0x140
[ ] bpf_tracing_prog_attach+0x1dc/0x450
[ ] bpf_raw_tracepoint_open+0x9a/0x1e0
[ ] ? find_held_lock+0x2d/0x90
[ ] ? lock_release+0x150/0x430
[ ] __sys_bpf+0xbd6/0x2700
[ ] ? lock_is_held_type+0xd8/0x130
[ ] __x64_sys_bpf+0x1c/0x20
[ ] do_syscall_64+0x3a/0x80
[ ] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ ] RIP: 0033:0x7fa9421defa9
[ ] Code: 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 9 f8 [...]
[ ] RSP: 002b:00007ffed743bd78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
[ ] RAX: ffffffffffffffda RBX: 00000000069d2480 RCX: 00007fa9421defa9
[ ] RDX: 0000000000000078 RSI: 00007ffed743bd80 RDI: 0000000000000011
[ ] RBP: 00007ffed743be00 R08: 0000000000bb7270 R09: 0000000000000000
[ ] R10: 00000000069da210 R11: 0000000000000246 R12: 0000000000000001
[ ] R13: 00007ffed743c4b0 R14: 00000000069d2480 R15: 0000000000000001
[ ] </TASK>
[ ] Modules linked in: klp_vm(OK)
[ ] ---[ end trace 0000000000000000 ]---
One way to trigger this is:
1. load a livepatch that patches kernel function xxx;
2. run bpftrace -e 'kfunc:xxx {}', this will fail (expected for now);
3. repeat #2 => gpf.
This is because the entry is added to direct_functions, but not removed.
Fix this by remove the entry from direct_functions when
register_ftrace_direct fails.
Also remove the last trailing space from ftrace.c, so we don't have to
worry about it anymore.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
RDMA/hfi1: Fix potential integer multiplication overflow errors
When multiplying of different types, an overflow is possible even when
storing the result in a larger type. This is because the conversion is
done after the multiplication. So arithmetic overflow and thus in
incorrect value is possible.
Correct an instance of this in the inter packet delay calculation. Fix by
ensuring one of the operands is u64 which will promote the other to u64 as
well ensuring no overflow.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
driver: base: fix UAF when driver_attach failed
When driver_attach(drv); failed, the driver_private will be freed.
But it has been added to the bus, which caused a UAF.
To fix it, we need to delete it from the bus when failed.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
ubi: ubi_create_volume: Fix use-after-free when volume creation failed
There is an use-after-free problem for 'eba_tbl' in ubi_create_volume()'s
error handling path:
ubi_eba_replace_table(vol, eba_tbl)
vol->eba_tbl = tbl
out_mapping:
ubi_eba_destroy_table(eba_tbl) // Free 'eba_tbl'
out_unlock:
put_device(&vol->dev)
vol_release
kfree(tbl->entries) // UAF
Fix it by removing redundant 'eba_tbl' releasing.
Fetch a reproducer in [Link].
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
usb: usbip: fix a refcount leak in stub_probe()
usb_get_dev() is called in stub_device_alloc(). When stub_probe() fails
after that, usb_put_dev() needs to be called to release the reference.
Fix this by moving usb_put_dev() to sdev_free error path handling.
Find this by code review.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
macsec: fix UAF bug for real_dev
Create a new macsec device but not get reference to real_dev. That can
not ensure that real_dev is freed after macsec. That will trigger the
UAF bug for real_dev as following:
==================================================================
BUG: KASAN: use-after-free in macsec_get_iflink+0x5f/0x70 drivers/net/macsec.c:3662
Call Trace:
...
macsec_get_iflink+0x5f/0x70 drivers/net/macsec.c:3662
dev_get_iflink+0x73/0xe0 net/core/dev.c:637
default_operstate net/core/link_watch.c:42 [inline]
rfc2863_policy+0x233/0x2d0 net/core/link_watch.c:54
linkwatch_do_dev+0x2a/0x150 net/core/link_watch.c:161
Allocated by task 22209:
...
alloc_netdev_mqs+0x98/0x1100 net/core/dev.c:10549
rtnl_create_link+0x9d7/0xc00 net/core/rtnetlink.c:3235
veth_newlink+0x20e/0xa90 drivers/net/veth.c:1748
Freed by task 8:
...
kfree+0xd6/0x4d0 mm/slub.c:4552
kvfree+0x42/0x50 mm/util.c:615
device_release+0x9f/0x240 drivers/base/core.c:2229
kobject_cleanup lib/kobject.c:673 [inline]
kobject_release lib/kobject.c:704 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1c8/0x540 lib/kobject.c:721
netdev_run_todo+0x72e/0x10b0 net/core/dev.c:10327
After commit faab39f63c1f ("net: allow out-of-order netdev unregistration")
and commit e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"), we
can add dev_hold_track() in macsec_dev_init() and dev_put_track() in
macsec_free_netdev() to fix the problem.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
blk-iolatency: Fix inflight count imbalances and IO hangs on offline
iolatency needs to track the number of inflight IOs per cgroup. As this
tracking can be expensive, it is disabled when no cgroup has iolatency
configured for the device. To ensure that the inflight counters stay
balanced, iolatency_set_limit() freezes the request_queue while manipulating
the enabled counter, which ensures that no IO is in flight and thus all
counters are zero.
Unfortunately, iolatency_set_limit() isn't the only place where the enabled
counter is manipulated. iolatency_pd_offline() can also dec the counter and
trigger disabling. As this disabling happens without freezing the q, this
can easily happen while some IOs are in flight and thus leak the counts.
This can be easily demonstrated by turning on iolatency on an one empty
cgroup while IOs are in flight in other cgroups and then removing the
cgroup. Note that iolatency shouldn't have been enabled elsewhere in the
system to ensure that removing the cgroup disables iolatency for the whole
device.
The following keeps flipping on and off iolatency on sda:
echo +io > /sys/fs/cgroup/cgroup.subtree_control
while true; do
mkdir -p /sys/fs/cgroup/test
echo '8:0 target=100000' > /sys/fs/cgroup/test/io.latency
sleep 1
rmdir /sys/fs/cgroup/test
sleep 1
done
and there's concurrent fio generating direct rand reads:
fio --name test --filename=/dev/sda --direct=1 --rw=randread \
--runtime=600 --time_based --iodepth=256 --numjobs=4 --bs=4k
while monitoring with the following drgn script:
while True:
for css in css_for_each_descendant_pre(prog['blkcg_root'].css.address_of_()):
for pos in hlist_for_each(container_of(css, 'struct blkcg', 'css').blkg_list):
blkg = container_of(pos, 'struct blkcg_gq', 'blkcg_node')
pd = blkg.pd[prog['blkcg_policy_iolatency'].plid]
if pd.value_() == 0:
continue
iolat = container_of(pd, 'struct iolatency_grp', 'pd')
inflight = iolat.rq_wait.inflight.counter.value_()
if inflight:
print(f'inflight={inflight} {disk_name(blkg.q.disk).decode("utf-8")} '
f'{cgroup_path(css.cgroup).decode("utf-8")}')
time.sleep(1)
The monitoring output looks like the following:
inflight=1 sda /user.slice
inflight=1 sda /user.slice
...
inflight=14 sda /user.slice
inflight=13 sda /user.slice
inflight=17 sda /user.slice
inflight=15 sda /user.slice
inflight=18 sda /user.slice
inflight=17 sda /user.slice
inflight=20 sda /user.slice
inflight=19 sda /user.slice <- fio stopped, inflight stuck at 19
inflight=19 sda /user.slice
inflight=19 sda /user.slice
If a cgroup with stuck inflight ends up getting throttled, the throttled IOs
will never get issued as there's no completion event to wake it up leading
to an indefinite hang.
This patch fixes the bug by unifying enable handling into a work item which
is automatically kicked off from iolatency_set_min_lat_nsec() which is
called from both iolatency_set_limit() and iolatency_pd_offline() paths.
Punting to a work item is necessary as iolatency_pd_offline() is called
under spinlocks while freezing a request_queue requires a sleepable context.
This also simplifies the code reducing LOC sans the comments and avoids the
unnecessary freezes which were happening whenever a cgroup's latency target
is newly set or cleared.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
tipc: check attribute length for bearer name
syzbot reported uninit-value:
=====================================================
BUG: KMSAN: uninit-value in string_nocheck lib/vsprintf.c:644 [inline]
BUG: KMSAN: uninit-value in string+0x4f9/0x6f0 lib/vsprintf.c:725
string_nocheck lib/vsprintf.c:644 [inline]
string+0x4f9/0x6f0 lib/vsprintf.c:725
vsnprintf+0x2222/0x3650 lib/vsprintf.c:2806
vprintk_store+0x537/0x2150 kernel/printk/printk.c:2158
vprintk_emit+0x28b/0xab0 kernel/printk/printk.c:2256
vprintk_default+0x86/0xa0 kernel/printk/printk.c:2283
vprintk+0x15f/0x180 kernel/printk/printk_safe.c:50
_printk+0x18d/0x1cf kernel/printk/printk.c:2293
tipc_enable_bearer net/tipc/bearer.c:371 [inline]
__tipc_nl_bearer_enable+0x2022/0x22a0 net/tipc/bearer.c:1033
tipc_nl_bearer_enable+0x6c/0xb0 net/tipc/bearer.c:1042
genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
- Do sanity check the attribute length for TIPC_NLA_BEARER_NAME.
- Do not use 'illegal name' in printing message.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
rtc: mt6397: check return value after calling platform_get_resource()
It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26