Linux: >> Linux Kernel >> 4.10.5 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
mmmremap.c: avoid pointless invalidate_range_start/end on mremap(old_size=0)
If an mremap() syscall with old_size=0 ends up in move_page_tables(), it
will call invalidate_range_start()/invalidate_range_end() unnecessarily,
i.e. with an empty range.
This causes a WARN in KVM's mmu_notifier. In the past, empty ranges
have been diagnosed to be off-by-one bugs, hence the WARNing. Given the
low (so far) number of unique reports, the benefits of detecting more
buggy callers seem to outweigh the cost of having to fix cases such as
this one, where userspace is doing something silly. In this particular
case, an early return from move_page_tables() is enough to fix the
issue.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
mm/mempolicy: fix mpol_new leak in shared_policy_replace
If mpol_new is allocated but not used in restart loop, mpol_new will be
freed via mpol_put before returning to the caller. But refcnt is not
initialized yet, so mpol_put could not do the right things and might
leak the unused mpol_new. This would happen if mempolicy was updated on
the shared shmem file while the sp->lock has been dropped during the
memory allocation.
This issue could be triggered easily with the below code snippet if
there are many processes doing the below work at the same time:
shmid = shmget((key_t)5566, 1024 * PAGE_SIZE, 0666|IPC_CREAT);
shm = shmat(shmid, 0, 0);
loop many times {
mbind(shm, 1024 * PAGE_SIZE, MPOL_LOCAL, mask, maxnode, 0);
mbind(shm + 128 * PAGE_SIZE, 128 * PAGE_SIZE, MPOL_DEFAULT, mask,
maxnode, 0);
}
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
drbd: Fix five use after free bugs in get_initial_state
In get_initial_state, it calls notify_initial_state_done(skb,..) if
cb->args[5]==1. If genlmsg_put() failed in notify_initial_state_done(),
the skb will be freed by nlmsg_free(skb).
Then get_initial_state will goto out and the freed skb will be used by
return value skb->len, which is a uaf bug.
What's worse, the same problem goes even further: skb can also be
freed in the notify_*_state_change -> notify_*_state calls below.
Thus 4 additional uaf bugs happened.
My patch lets the problem callee functions: notify_initial_state_done
and notify_*_state_change return an error code if errors happen.
So that the error codes could be propagated and the uaf bugs can be avoid.
v2 reports a compilation warning. This v3 fixed this warning and built
successfully in my local environment with no additional warnings.
v2: https://lore.kernel.org/patchwork/patch/1435218/
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: fix leak of nested actions
While parsing user-provided actions, openvswitch module may dynamically
allocate memory and store pointers in the internal copy of the actions.
So this memory has to be freed while destroying the actions.
Currently there are only two such actions: ct() and set(). However,
there are many actions that can hold nested lists of actions and
ovs_nla_free_flow_actions() just jumps over them leaking the memory.
For example, removal of the flow with the following actions will lead
to a leak of the memory allocated by nf_ct_tmpl_alloc():
actions:clone(ct(commit),0)
Non-freed set() action may also leak the 'dst' structure for the
tunnel info including device references.
Under certain conditions with a high rate of flow rotation that may
cause significant memory leak problem (2MB per second in reporter's
case). The problem is also hard to mitigate, because the user doesn't
have direct control over the datapath flows generated by OVS.
Fix that by iterating over all the nested actions and freeing
everything that needs to be freed recursively.
New build time assertion should protect us from this problem if new
actions will be added in the future.
Unfortunately, openvswitch module doesn't use NLA_F_NESTED, so all
attributes has to be explicitly checked. sample() and clone() actions
are mixing extra attributes into the user-provided action list. That
prevents some code generalization too.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
gpio: Restrict usage of GPIO chip irq members before initialization
GPIO chip irq members are exposed before they could be completely
initialized and this leads to race conditions.
One such issue was observed for the gc->irq.domain variable which
was accessed through the I2C interface in gpiochip_to_irq() before
it could be initialized by gpiochip_add_irqchip(). This resulted in
Kernel NULL pointer dereference.
Following are the logs for reference :-
kernel: Call Trace:
kernel: gpiod_to_irq+0x53/0x70
kernel: acpi_dev_gpio_irq_get_by+0x113/0x1f0
kernel: i2c_acpi_get_irq+0xc0/0xd0
kernel: i2c_device_probe+0x28a/0x2a0
kernel: really_probe+0xf2/0x460
kernel: RIP: 0010:gpiochip_to_irq+0x47/0xc0
To avoid such scenarios, restrict usage of GPIO chip irq members before
they are completely initialized.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
irqchip/gic-v3: Fix GICR_CTLR.RWP polling
It turns out that our polling of RWP is totally wrong when checking
for it in the redistributors, as we test the *distributor* bit index,
whereas it is a different bit number in the RDs... Oopsie boo.
This is embarassing. Not only because it is wrong, but also because
it took *8 years* to notice the blunder...
Just fix the damn thing.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix qgroup reserve overflow the qgroup limit
We use extent_changeset->bytes_changed in qgroup_reserve_data() to record
how many bytes we set for EXTENT_QGROUP_RESERVED state. Currently the
bytes_changed is set as "unsigned int", and it will overflow if we try to
fallocate a range larger than 4GiB. The result is we reserve less bytes
and eventually break the qgroup limit.
Unlike regular buffered/direct write, which we use one changeset for
each ordered extent, which can never be larger than 256M. For
fallocate, we use one changeset for the whole range, thus it no longer
respects the 256M per extent limit, and caused the problem.
The following example test script reproduces the problem:
$ cat qgroup-overflow.sh
#!/bin/bash
DEV=/dev/sdj
MNT=/mnt/sdj
mkfs.btrfs -f $DEV
mount $DEV $MNT
# Set qgroup limit to 2GiB.
btrfs quota enable $MNT
btrfs qgroup limit 2G $MNT
# Try to fallocate a 3GiB file. This should fail.
echo
echo "Try to fallocate a 3GiB file..."
fallocate -l 3G $MNT/3G.file
# Try to fallocate a 5GiB file.
echo
echo "Try to fallocate a 5GiB file..."
fallocate -l 5G $MNT/5G.file
# See we break the qgroup limit.
echo
sync
btrfs qgroup show -r $MNT
umount $MNT
When running the test:
$ ./qgroup-overflow.sh
(...)
Try to fallocate a 3GiB file...
fallocate: fallocate failed: Disk quota exceeded
Try to fallocate a 5GiB file...
qgroupid rfer excl max_rfer
-------- ---- ---- --------
0/5 5.00GiB 5.00GiB 2.00GiB
Since we have no control of how bytes_changed is used, it's better to
set it to u64.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
cifs: potential buffer overflow in handling symlinks
Smatch printed a warning:
arch/x86/crypto/poly1305_glue.c:198 poly1305_update_arch() error:
__memcpy() 'dctx->buf' too small (16 vs u32max)
It's caused because Smatch marks 'link_len' as untrusted since it comes
from sscanf(). Add a check to ensure that 'link_len' is not larger than
the size of the 'link_str' buffer.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
nfc: nci: add flush_workqueue to prevent uaf
Our detector found a concurrent use-after-free bug when detaching an
NCI device. The main reason for this bug is the unexpected scheduling
between the used delayed mechanism (timer and workqueue).
The race can be demonstrated below:
Thread-1 Thread-2
| nci_dev_up()
| nci_open_device()
| __nci_request(nci_reset_req)
| nci_send_cmd
| queue_work(cmd_work)
nci_unregister_device() |
nci_close_device() | ...
del_timer_sync(cmd_timer)[1] |
... | Worker
nci_free_device() | nci_cmd_work()
kfree(ndev)[3] | mod_timer(cmd_timer)[2]
In short, the cleanup routine thought that the cmd_timer has already
been detached by [1] but the mod_timer can re-attach the timer [2], even
it is already released [3], resulting in UAF.
This UAF is easy to trigger, crash trace by POC is like below
[ 66.703713] ==================================================================
[ 66.703974] BUG: KASAN: use-after-free in enqueue_timer+0x448/0x490
[ 66.703974] Write of size 8 at addr ffff888009fb7058 by task kworker/u4:1/33
[ 66.703974]
[ 66.703974] CPU: 1 PID: 33 Comm: kworker/u4:1 Not tainted 5.18.0-rc2 #5
[ 66.703974] Workqueue: nfc2_nci_cmd_wq nci_cmd_work
[ 66.703974] Call Trace:
[ 66.703974] <TASK>
[ 66.703974] dump_stack_lvl+0x57/0x7d
[ 66.703974] print_report.cold+0x5e/0x5db
[ 66.703974] ? enqueue_timer+0x448/0x490
[ 66.703974] kasan_report+0xbe/0x1c0
[ 66.703974] ? enqueue_timer+0x448/0x490
[ 66.703974] enqueue_timer+0x448/0x490
[ 66.703974] __mod_timer+0x5e6/0xb80
[ 66.703974] ? mark_held_locks+0x9e/0xe0
[ 66.703974] ? try_to_del_timer_sync+0xf0/0xf0
[ 66.703974] ? lockdep_hardirqs_on_prepare+0x17b/0x410
[ 66.703974] ? queue_work_on+0x61/0x80
[ 66.703974] ? lockdep_hardirqs_on+0xbf/0x130
[ 66.703974] process_one_work+0x8bb/0x1510
[ 66.703974] ? lockdep_hardirqs_on_prepare+0x410/0x410
[ 66.703974] ? pwq_dec_nr_in_flight+0x230/0x230
[ 66.703974] ? rwlock_bug.part.0+0x90/0x90
[ 66.703974] ? _raw_spin_lock_irq+0x41/0x50
[ 66.703974] worker_thread+0x575/0x1190
[ 66.703974] ? process_one_work+0x1510/0x1510
[ 66.703974] kthread+0x2a0/0x340
[ 66.703974] ? kthread_complete_and_exit+0x20/0x20
[ 66.703974] ret_from_fork+0x22/0x30
[ 66.703974] </TASK>
[ 66.703974]
[ 66.703974] Allocated by task 267:
[ 66.703974] kasan_save_stack+0x1e/0x40
[ 66.703974] __kasan_kmalloc+0x81/0xa0
[ 66.703974] nci_allocate_device+0xd3/0x390
[ 66.703974] nfcmrvl_nci_register_dev+0x183/0x2c0
[ 66.703974] nfcmrvl_nci_uart_open+0xf2/0x1dd
[ 66.703974] nci_uart_tty_ioctl+0x2c3/0x4a0
[ 66.703974] tty_ioctl+0x764/0x1310
[ 66.703974] __x64_sys_ioctl+0x122/0x190
[ 66.703974] do_syscall_64+0x3b/0x90
[ 66.703974] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 66.703974]
[ 66.703974] Freed by task 406:
[ 66.703974] kasan_save_stack+0x1e/0x40
[ 66.703974] kasan_set_track+0x21/0x30
[ 66.703974] kasan_set_free_info+0x20/0x30
[ 66.703974] __kasan_slab_free+0x108/0x170
[ 66.703974] kfree+0xb0/0x330
[ 66.703974] nfcmrvl_nci_unregister_dev+0x90/0xd0
[ 66.703974] nci_uart_tty_close+0xdf/0x180
[ 66.703974] tty_ldisc_kill+0x73/0x110
[ 66.703974] tty_ldisc_hangup+0x281/0x5b0
[ 66.703974] __tty_hangup.part.0+0x431/0x890
[ 66.703974] tty_release+0x3a8/0xc80
[ 66.703974] __fput+0x1f0/0x8c0
[ 66.703974] task_work_run+0xc9/0x170
[ 66.703974] exit_to_user_mode_prepare+0x194/0x1a0
[ 66.703974] syscall_exit_to_user_mode+0x19/0x50
[ 66.703974] do_syscall_64+0x48/0x90
[ 66.703974] entry_SYSCALL_64_after_hwframe+0x44/0x
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-02-26
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: stmmac: fix altr_tse_pcs function when using a fixed-link
When using a fixed-link, the altr_tse_pcs driver crashes
due to null-pointer dereference as no phy_device is provided to
tse_pcs_fix_mac_speed function. Fix this by adding a check for
phy_dev before calling the tse_pcs_fix_mac_speed() function.
Also clean up the tse_pcs_fix_mac_speed function a bit. There is
no need to check for splitter_base and sgmii_adapter_base
because the driver will fail if these 2 variables are not
derived from the device tree.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-02-26