Linux: >> Linux Kernel >> 2.6.27.25 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
net: fix use-after-free in tw_timer_handler
A real world panic issue was found as follow in Linux 5.4.
BUG: unable to handle page fault for address: ffffde49a863de28
PGD 7e6fe62067 P4D 7e6fe62067 PUD 7e6fe63067 PMD f51e064067 PTE 0
RIP: 0010:tw_timer_handler+0x20/0x40
Call Trace:
<IRQ>
call_timer_fn+0x2b/0x120
run_timer_softirq+0x1ef/0x450
__do_softirq+0x10d/0x2b8
irq_exit+0xc7/0xd0
smp_apic_timer_interrupt+0x68/0x120
apic_timer_interrupt+0xf/0x20
This issue was also reported since 2017 in the thread [1],
unfortunately, the issue was still can be reproduced after fixing
DCCP.
The ipv4_mib_exit_net is called before tcp_sk_exit_batch when a net
namespace is destroyed since tcp_sk_ops is registered befrore
ipv4_mib_ops, which means tcp_sk_ops is in the front of ipv4_mib_ops
in the list of pernet_list. There will be a use-after-free on
net->mib.net_statistics in tw_timer_handler after ipv4_mib_exit_net
if there are some inflight time-wait timers.
This bug is not introduced by commit f2bf415cfed7 ("mib: add net to
NET_ADD_STATS_BH") since the net_statistics is a global variable
instead of dynamic allocation and freeing. Actually, commit
61a7e26028b9 ("mib: put net statistics on struct net") introduces
the bug since it put net statistics on struct net and free it when
net namespace is destroyed.
Moving init_ipv4_mibs() to the front of tcp_init() to fix this bug
and replace pr_crit() with panic() since continuing is meaningless
when init_ipv4_mibs() fails.
[1] https://groups.google.com/g/syzkaller/c/p1tn-_Kc6l4/m/smuL_FMAAgAJ?pli=1
CVSS Score
7.8
EPSS Score
0.0
Published
2024-02-27
In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: intel-sdw-acpi: harden detection of controller
The existing code currently sets a pointer to an ACPI handle before
checking that it's actually a SoundWire controller. This can lead to
issues where the graph walk continues and eventually fails, but the
pointer was set already.
This patch changes the logic so that the information provided to
the caller is set when a controller is found.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-27
In the Linux kernel, the following vulnerability has been resolved:
parisc: Clear stale IIR value on instruction access rights trap
When a trap 7 (Instruction access rights) occurs, this means the CPU
couldn't execute an instruction due to missing execute permissions on
the memory region. In this case it seems the CPU didn't even fetched
the instruction from memory and thus did not store it in the cr19 (IIR)
register before calling the trap handler. So, the trap handler will find
some random old stale value in cr19.
This patch simply overwrites the stale IIR value with a constant magic
"bad food" value (0xbaadf00d), in the hope people don't start to try to
understand the various random IIR values in trap 7 dumps.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-27
In the Linux kernel, the following vulnerability has been resolved:
Input: appletouch - initialize work before device registration
Syzbot has reported warning in __flush_work(). This warning is caused by
work->func == NULL, which means missing work initialization.
This may happen, since input_dev->close() calls
cancel_work_sync(&dev->work), but dev->work initalization happens _after_
input_register_device() call.
So this patch moves dev->work initialization before registering input
device
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-27
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid potential deadlock
Using f2fs_trylock_op() in f2fs_write_compressed_pages() to avoid potential
deadlock like we did in f2fs_write_single_data_page().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-26
In the Linux kernel, the following vulnerability has been resolved:
HID: usbhid: fix info leak in hid_submit_ctrl
In hid_submit_ctrl(), the way of calculating the report length doesn't
take into account that report->size can be zero. When running the
syzkaller reproducer, a report of size 0 causes hid_submit_ctrl) to
calculate transfer_buffer_length as 16384. When this urb is passed to
the usb core layer, KMSAN reports an info leak of 16384 bytes.
To fix this, first modify hid_report_len() to account for the zero
report size case by using DIV_ROUND_UP for the division. Then, call it
from hid_submit_ctrl().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-26
In the Linux kernel, the following vulnerability has been resolved:
netlabel: fix out-of-bounds memory accesses
There are two array out-of-bounds memory accesses, one in
cipso_v4_map_lvl_valid(), the other in netlbl_bitmap_walk(). Both
errors are embarassingly simple, and the fixes are straightforward.
As a FYI for anyone backporting this patch to kernels prior to v4.8,
you'll want to apply the netlbl_bitmap_walk() patch to
cipso_v4_bitmap_walk() as netlbl_bitmap_walk() doesn't exist before
Linux v4.8.
CVSS Score
7.1
EPSS Score
0.0
Published
2024-02-26
In the Linux kernel, the following vulnerability has been resolved:
ext4: regenerate buddy after block freeing failed if under fc replay
This mostly reverts commit 6bd97bf273bd ("ext4: remove redundant
mb_regenerate_buddy()") and reintroduces mb_regenerate_buddy(). Based on
code in mb_free_blocks(), fast commit replay can end up marking as free
blocks that are already marked as such. This causes corruption of the
buddy bitmap so we need to regenerate it in that case.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-26
In the Linux kernel, the following vulnerability has been resolved:
net: hso: fix null-ptr-deref during tty device unregistration
Multiple ttys try to claim the same the minor number causing a double
unregistration of the same device. The first unregistration succeeds
but the next one results in a null-ptr-deref.
The get_free_serial_index() function returns an available minor number
but doesn't assign it immediately. The assignment is done by the caller
later. But before this assignment, calls to get_free_serial_index()
would return the same minor number.
Fix this by modifying get_free_serial_index to assign the minor number
immediately after one is found to be and rename it to obtain_minor()
to better reflect what it does. Similary, rename set_serial_by_index()
to release_minor() and modify it to free up the minor number of the
given hso_serial. Every obtain_minor() should have corresponding
release_minor() call.
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-26
In the Linux kernel, the following vulnerability has been resolved:
net: hso: fix NULL-deref on disconnect regression
Commit 8a12f8836145 ("net: hso: fix null-ptr-deref during tty device
unregistration") fixed the racy minor allocation reported by syzbot, but
introduced an unconditional NULL-pointer dereference on every disconnect
instead.
Specifically, the serial device table must no longer be accessed after
the minor has been released by hso_serial_tty_unregister().
CVSS Score
5.5
EPSS Score
0.0
Published
2024-02-26