In the Linux kernel, the following vulnerability has been resolved:
usb: renesas_usbhs: Flush the notify_hotplug_work
When performing continuous unbind/bind operations on the USB drivers
available on the Renesas RZ/G2L SoC, a kernel crash with the message
"Unable to handle kernel NULL pointer dereference at virtual address"
may occur. This issue points to the usbhsc_notify_hotplug() function.
Flush the delayed work to avoid its execution when driver resources are
unavailable.
In the Linux kernel, the following vulnerability has been resolved:
usb: typec: ucsi: Fix NULL pointer access
Resources should be released only after all threads that utilize them
have been destroyed.
This commit ensures that resources are not released prematurely by waiting
for the associated workqueue to complete before deallocating them.
In the Linux kernel, the following vulnerability has been resolved:
sched/fair: Fix potential memory corruption in child_cfs_rq_on_list
child_cfs_rq_on_list attempts to convert a 'prev' pointer to a cfs_rq.
This 'prev' pointer can originate from struct rq's leaf_cfs_rq_list,
making the conversion invalid and potentially leading to memory
corruption. Depending on the relative positions of leaf_cfs_rq_list and
the task group (tg) pointer within the struct, this can cause a memory
fault or access garbage data.
The issue arises in list_add_leaf_cfs_rq, where both
cfs_rq->leaf_cfs_rq_list and rq->leaf_cfs_rq_list are added to the same
leaf list. Also, rq->tmp_alone_branch can be set to rq->leaf_cfs_rq_list.
This adds a check `if (prev == &rq->leaf_cfs_rq_list)` after the main
conditional in child_cfs_rq_on_list. This ensures that the container_of
operation will convert a correct cfs_rq struct.
This check is sufficient because only cfs_rqs on the same CPU are added
to the list, so verifying the 'prev' pointer against the current rq's list
head is enough.
Fixes a potential memory corruption issue that due to current struct
layout might not be manifesting as a crash but could lead to unpredictable
behavior when the layout changes.
In the Linux kernel, the following vulnerability has been resolved:
vlan: enforce underlying device type
Currently, VLAN devices can be created on top of non-ethernet devices.
Besides the fact that it doesn't make much sense, this also causes a
bug which leaks the address of a kernel function to usermode.
When creating a VLAN device, we initialize GARP (garp_init_applicant)
and MRP (mrp_init_applicant) for the underlying device.
As part of the initialization process, we add the multicast address of
each applicant to the underlying device, by calling dev_mc_add.
__dev_mc_add uses dev->addr_len to determine the length of the new
multicast address.
This causes an out-of-bounds read if dev->addr_len is greater than 6,
since the multicast addresses provided by GARP and MRP are only 6
bytes long.
This behaviour can be reproduced using the following commands:
ip tunnel add gretest mode ip6gre local ::1 remote ::2 dev lo
ip l set up dev gretest
ip link add link gretest name vlantest type vlan id 100
Then, the following command will display the address of garp_pdu_rcv:
ip maddr show | grep 01:80:c2:00:00:21
Fix the bug by enforcing the type of the underlying device during VLAN
device initialization.
In the Linux kernel, the following vulnerability has been resolved:
ppp: Fix KMSAN uninit-value warning with bpf
Syzbot caught an "KMSAN: uninit-value" warning [1], which is caused by the
ppp driver not initializing a 2-byte header when using socket filter.
The following code can generate a PPP filter BPF program:
'''
struct bpf_program fp;
pcap_t *handle;
handle = pcap_open_dead(DLT_PPP_PPPD, 65535);
pcap_compile(handle, &fp, "ip and outbound", 0, 0);
bpf_dump(&fp, 1);
'''
Its output is:
'''
(000) ldh [2]
(001) jeq #0x21 jt 2 jf 5
(002) ldb [0]
(003) jeq #0x1 jt 4 jf 5
(004) ret #65535
(005) ret #0
'''
Wen can find similar code at the following link:
https://github.com/ppp-project/ppp/blob/master/pppd/options.c#L1680
The maintainer of this code repository is also the original maintainer
of the ppp driver.
As you can see the BPF program skips 2 bytes of data and then reads the
'Protocol' field to determine if it's an IP packet. Then it read the first
byte of the first 2 bytes to determine the direction.
The issue is that only the first byte indicating direction is initialized
in current ppp driver code while the second byte is not initialized.
For normal BPF programs generated by libpcap, uninitialized data won't be
used, so it's not a problem. However, for carefully crafted BPF programs,
such as those generated by syzkaller [2], which start reading from offset
0, the uninitialized data will be used and caught by KMSAN.
[1] https://syzkaller.appspot.com/bug?extid=853242d9c9917165d791
[2] https://syzkaller.appspot.com/text?tag=ReproC&x=11994913980000
In the Linux kernel, the following vulnerability has been resolved:
mm: memory-failure: update ttu flag inside unmap_poisoned_folio
Patch series "mm: memory_failure: unmap poisoned folio during migrate
properly", v3.
Fix two bugs during folio migration if the folio is poisoned.
This patch (of 3):
Commit 6da6b1d4a7df ("mm/hwpoison: convert TTU_IGNORE_HWPOISON to
TTU_HWPOISON") introduce TTU_HWPOISON to replace TTU_IGNORE_HWPOISON in
order to stop send SIGBUS signal when accessing an error page after a
memory error on a clean folio. However during page migration, anon folio
must be set with TTU_HWPOISON during unmap_*(). For pagecache we need
some policy just like the one in hwpoison_user_mappings to set this flag.
So move this policy from hwpoison_user_mappings to unmap_poisoned_folio to
handle this warning properly.
Warning will be produced during unamp poison folio with the following log:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 365 at mm/rmap.c:1847 try_to_unmap_one+0x8fc/0xd3c
Modules linked in:
CPU: 1 UID: 0 PID: 365 Comm: bash Tainted: G W 6.13.0-rc1-00018-gacdb4bbda7ab #42
Tainted: [W]=WARN
Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : try_to_unmap_one+0x8fc/0xd3c
lr : try_to_unmap_one+0x3dc/0xd3c
Call trace:
try_to_unmap_one+0x8fc/0xd3c (P)
try_to_unmap_one+0x3dc/0xd3c (L)
rmap_walk_anon+0xdc/0x1f8
rmap_walk+0x3c/0x58
try_to_unmap+0x88/0x90
unmap_poisoned_folio+0x30/0xa8
do_migrate_range+0x4a0/0x568
offline_pages+0x5a4/0x670
memory_block_action+0x17c/0x374
memory_subsys_offline+0x3c/0x78
device_offline+0xa4/0xd0
state_store+0x8c/0xf0
dev_attr_store+0x18/0x2c
sysfs_kf_write+0x44/0x54
kernfs_fop_write_iter+0x118/0x1a8
vfs_write+0x3a8/0x4bc
ksys_write+0x6c/0xf8
__arm64_sys_write+0x1c/0x28
invoke_syscall+0x44/0x100
el0_svc_common.constprop.0+0x40/0xe0
do_el0_svc+0x1c/0x28
el0_svc+0x30/0xd0
el0t_64_sync_handler+0xc8/0xcc
el0t_64_sync+0x198/0x19c
---[ end trace 0000000000000000 ]---
[mawupeng1@huawei.com: unmap_poisoned_folio(): remove shadowed local `mapping', per Miaohe]
In the Linux kernel, the following vulnerability has been resolved:
wifi: nl80211: reject cooked mode if it is set along with other flags
It is possible to set both MONITOR_FLAG_COOK_FRAMES and MONITOR_FLAG_ACTIVE
flags simultaneously on the same monitor interface from the userspace. This
causes a sub-interface to be created with no IEEE80211_SDATA_IN_DRIVER bit
set because the monitor interface is in the cooked state and it takes
precedence over all other states. When the interface is then being deleted
the kernel calls WARN_ONCE() from check_sdata_in_driver() because of missing
that bit.
Fix this by rejecting MONITOR_FLAG_COOK_FRAMES if it is set along with
other flags.
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
In the Linux kernel, the following vulnerability has been resolved:
wifi: cfg80211: regulatory: improve invalid hints checking
Syzbot keeps reporting an issue [1] that occurs when erroneous symbols
sent from userspace get through into user_alpha2[] via
regulatory_hint_user() call. Such invalid regulatory hints should be
rejected.
While a sanity check from commit 47caf685a685 ("cfg80211: regulatory:
reject invalid hints") looks to be enough to deter these very cases,
there is a way to get around it due to 2 reasons.
1) The way isalpha() works, symbols other than latin lower and
upper letters may be used to determine a country/domain.
For instance, greek letters will also be considered upper/lower
letters and for such characters isalpha() will return true as well.
However, ISO-3166-1 alpha2 codes should only hold latin
characters.
2) While processing a user regulatory request, between
reg_process_hint_user() and regulatory_hint_user() there happens to
be a call to queue_regulatory_request() which modifies letters in
request->alpha2[] with toupper(). This works fine for latin symbols,
less so for weird letter characters from the second part of _ctype[].
Syzbot triggers a warning in is_user_regdom_saved() by first sending
over an unexpected non-latin letter that gets malformed by toupper()
into a character that ends up failing isalpha() check.
Prevent this by enhancing is_an_alpha2() to ensure that incoming
symbols are latin letters and nothing else.
[1] Syzbot report:
------------[ cut here ]------------
Unexpected user alpha2: A�
WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 is_user_regdom_saved net/wireless/reg.c:440 [inline]
WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 restore_alpha2 net/wireless/reg.c:3424 [inline]
WARNING: CPU: 1 PID: 964 at net/wireless/reg.c:442 restore_regulatory_settings+0x3c0/0x1e50 net/wireless/reg.c:3516
Modules linked in:
CPU: 1 UID: 0 PID: 964 Comm: kworker/1:2 Not tainted 6.12.0-rc5-syzkaller-00044-gc1e939a21eb1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_power_efficient crda_timeout_work
RIP: 0010:is_user_regdom_saved net/wireless/reg.c:440 [inline]
RIP: 0010:restore_alpha2 net/wireless/reg.c:3424 [inline]
RIP: 0010:restore_regulatory_settings+0x3c0/0x1e50 net/wireless/reg.c:3516
...
Call Trace:
<TASK>
crda_timeout_work+0x27/0x50 net/wireless/reg.c:542
process_one_work kernel/workqueue.c:3229 [inline]
process_scheduled_works+0xa65/0x1850 kernel/workqueue.c:3310
worker_thread+0x870/0xd30 kernel/workqueue.c:3391
kthread+0x2f2/0x390 kernel/kthread.c:389
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
x86/amd_nb: Use rdmsr_safe() in amd_get_mmconfig_range()
Xen doesn't offer MSR_FAM10H_MMIO_CONF_BASE to all guests. This results
in the following warning:
unchecked MSR access error: RDMSR from 0xc0010058 at rIP: 0xffffffff8101d19f (xen_do_read_msr+0x7f/0xa0)
Call Trace:
xen_read_msr+0x1e/0x30
amd_get_mmconfig_range+0x2b/0x80
quirk_amd_mmconfig_area+0x28/0x100
pnp_fixup_device+0x39/0x50
__pnp_add_device+0xf/0x150
pnp_add_device+0x3d/0x100
pnpacpi_add_device_handler+0x1f9/0x280
acpi_ns_get_device_callback+0x104/0x1c0
acpi_ns_walk_namespace+0x1d0/0x260
acpi_get_devices+0x8a/0xb0
pnpacpi_init+0x50/0x80
do_one_initcall+0x46/0x2e0
kernel_init_freeable+0x1da/0x2f0
kernel_init+0x16/0x1b0
ret_from_fork+0x30/0x50
ret_from_fork_asm+0x1b/0x30
based on quirks for a "PNP0c01" device. Treating MMCFG as disabled is the
right course of action, so no change is needed there.
This was most likely exposed by fixing the Xen MSR accessors to not be
silently-safe.