Linux: >> Linux Kernel >> 4.3.2 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Protect mgmt_pending list with its own lock
This uses a mutex to protect from concurrent access of mgmt_pending
list which can cause crashes like:
==================================================================
BUG: KASAN: slab-use-after-free in hci_sock_get_channel+0x60/0x68 net/bluetooth/hci_sock.c:91
Read of size 2 at addr ffff0000c48885b2 by task syz.4.334/7318
CPU: 0 UID: 0 PID: 7318 Comm: syz.4.334 Not tainted 6.15.0-rc7-syzkaller-g187899f4124a #0 PREEMPT
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call trace:
show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
__dump_stack+0x30/0x40 lib/dump_stack.c:94
dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
print_address_description+0xa8/0x254 mm/kasan/report.c:408
print_report+0x68/0x84 mm/kasan/report.c:521
kasan_report+0xb0/0x110 mm/kasan/report.c:634
__asan_report_load2_noabort+0x20/0x2c mm/kasan/report_generic.c:379
hci_sock_get_channel+0x60/0x68 net/bluetooth/hci_sock.c:91
mgmt_pending_find+0x7c/0x140 net/bluetooth/mgmt_util.c:223
pending_find net/bluetooth/mgmt.c:947 [inline]
remove_adv_monitor+0x44/0x1a4 net/bluetooth/mgmt.c:5445
hci_mgmt_cmd+0x780/0xc00 net/bluetooth/hci_sock.c:1712
hci_sock_sendmsg+0x544/0xbb0 net/bluetooth/hci_sock.c:1832
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg net/socket.c:727 [inline]
sock_write_iter+0x25c/0x378 net/socket.c:1131
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x62c/0x97c fs/read_write.c:684
ksys_write+0x120/0x210 fs/read_write.c:736
__do_sys_write fs/read_write.c:747 [inline]
__se_sys_write fs/read_write.c:744 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:744
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767
el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Allocated by task 7037:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x40/0x78 mm/kasan/common.c:68
kasan_save_alloc_info+0x44/0x54 mm/kasan/generic.c:562
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x9c/0xb4 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4327 [inline]
__kmalloc_noprof+0x2fc/0x4c8 mm/slub.c:4339
kmalloc_noprof include/linux/slab.h:909 [inline]
sk_prot_alloc+0xc4/0x1f0 net/core/sock.c:2198
sk_alloc+0x44/0x3ac net/core/sock.c:2254
bt_sock_alloc+0x4c/0x300 net/bluetooth/af_bluetooth.c:148
hci_sock_create+0xa8/0x194 net/bluetooth/hci_sock.c:2202
bt_sock_create+0x14c/0x24c net/bluetooth/af_bluetooth.c:132
__sock_create+0x43c/0x91c net/socket.c:1541
sock_create net/socket.c:1599 [inline]
__sys_socket_create net/socket.c:1636 [inline]
__sys_socket+0xd4/0x1c0 net/socket.c:1683
__do_sys_socket net/socket.c:1697 [inline]
__se_sys_socket net/socket.c:1695 [inline]
__arm64_sys_socket+0x7c/0x94 net/socket.c:1695
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
el0_svc+0x58/0x17c arch/arm64/kernel/entry-common.c:767
el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600
Freed by task 6607:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x40/0x78 mm/kasan/common.c:68
kasan_save_free_info+0x58/0x70 mm/kasan/generic.c:576
poison_slab_object mm/kasan/common.c:247 [inline]
__kasan_slab_free+0x68/0x88 mm/kasan/common.c:264
kasan_slab_free include/linux/kasan.h:233 [inline
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
scsi: core: ufs: Fix a hang in the error handler
ufshcd_err_handling_prepare() calls ufshcd_rpm_get_sync(). The latter
function can only succeed if UFSHCD_EH_IN_PROGRESS is not set because
resuming involves submitting a SCSI command and ufshcd_queuecommand()
returns SCSI_MLQUEUE_HOST_BUSY if UFSHCD_EH_IN_PROGRESS is set. Fix this
hang by setting UFSHCD_EH_IN_PROGRESS after ufshcd_rpm_get_sync() has
been called instead of before.
Backtrace:
__switch_to+0x174/0x338
__schedule+0x600/0x9e4
schedule+0x7c/0xe8
schedule_timeout+0xa4/0x1c8
io_schedule_timeout+0x48/0x70
wait_for_common_io+0xa8/0x160 //waiting on START_STOP
wait_for_completion_io_timeout+0x10/0x20
blk_execute_rq+0xe4/0x1e4
scsi_execute_cmd+0x108/0x244
ufshcd_set_dev_pwr_mode+0xe8/0x250
__ufshcd_wl_resume+0x94/0x354
ufshcd_wl_runtime_resume+0x3c/0x174
scsi_runtime_resume+0x64/0xa4
rpm_resume+0x15c/0xa1c
__pm_runtime_resume+0x4c/0x90 // Runtime resume ongoing
ufshcd_err_handler+0x1a0/0xd08
process_one_work+0x174/0x808
worker_thread+0x15c/0x490
kthread+0xf4/0x1ec
ret_from_fork+0x10/0x20
[ bvanassche: rewrote patch description ]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Disable SCO support if READ_VOICE_SETTING is unsupported/broken
A SCO connection without the proper voice_setting can cause
the controller to lock up.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
VMCI: fix race between vmci_host_setup_notify and vmci_ctx_unset_notify
During our test, it is found that a warning can be trigger in try_grab_folio
as follow:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 1678 at mm/gup.c:147 try_grab_folio+0x106/0x130
Modules linked in:
CPU: 0 UID: 0 PID: 1678 Comm: syz.3.31 Not tainted 6.15.0-rc5 #163 PREEMPT(undef)
RIP: 0010:try_grab_folio+0x106/0x130
Call Trace:
<TASK>
follow_huge_pmd+0x240/0x8e0
follow_pmd_mask.constprop.0.isra.0+0x40b/0x5c0
follow_pud_mask.constprop.0.isra.0+0x14a/0x170
follow_page_mask+0x1c2/0x1f0
__get_user_pages+0x176/0x950
__gup_longterm_locked+0x15b/0x1060
? gup_fast+0x120/0x1f0
gup_fast_fallback+0x17e/0x230
get_user_pages_fast+0x5f/0x80
vmci_host_unlocked_ioctl+0x21c/0xf80
RIP: 0033:0x54d2cd
---[ end trace 0000000000000000 ]---
Digging into the source, context->notify_page may init by get_user_pages_fast
and can be seen in vmci_ctx_unset_notify which will try to put_page. However
get_user_pages_fast is not finished here and lead to following
try_grab_folio warning. The race condition is shown as follow:
cpu0 cpu1
vmci_host_do_set_notify
vmci_host_setup_notify
get_user_pages_fast(uva, 1, FOLL_WRITE, &context->notify_page);
lockless_pages_from_mm
gup_pgd_range
gup_huge_pmd // update &context->notify_page
vmci_host_do_set_notify
vmci_ctx_unset_notify
notify_page = context->notify_page;
if (notify_page)
put_page(notify_page); // page is freed
__gup_longterm_locked
__get_user_pages
follow_trans_huge_pmd
try_grab_folio // warn here
To slove this, use local variable page to make notify_page can be seen
after finish get_user_pages_fast.
CVSS Score
7.0
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Kill timer properly at removal
The USB-audio MIDI code initializes the timer, but in a rare case, the
driver might be freed without the disconnect call. This leaves the
timer in an active state while the assigned object is released via
snd_usbmidi_free(), which ends up with a kernel warning when the debug
configuration is enabled, as spotted by fuzzer.
For avoiding the problem, put timer_shutdown_sync() at
snd_usbmidi_free(), so that the timer can be killed properly.
While we're at it, replace the existing timer_delete_sync() at the
disconnect callback with timer_shutdown_sync(), too.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
wifi: iwlwifi: don't warn when if there is a FW error
iwl_trans_reclaim is warning if it is called when the FW is not alive.
But if it is called when there is a pending restart, i.e. after a FW
error, there is no need to warn, instead - return silently.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
net: cadence: macb: Fix a possible deadlock in macb_halt_tx.
There is a situation where after THALT is set high, TGO stays high as
well. Because jiffies are never updated, as we are in a context with
interrupts disabled, we never exit that loop and have a deadlock.
That deadlock was noticed on a sama5d4 device that stayed locked for days.
Use retries instead of jiffies so that the timeout really works and we do
not have a deadlock anymore.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-03
In the Linux kernel, the following vulnerability has been resolved:
mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race
huge_pmd_unshare() drops a reference on a page table that may have
previously been shared across processes, potentially turning it into a
normal page table used in another process in which unrelated VMAs can
afterwards be installed.
If this happens in the middle of a concurrent gup_fast(), gup_fast() could
end up walking the page tables of another process. While I don't see any
way in which that immediately leads to kernel memory corruption, it is
really weird and unexpected.
Fix it with an explicit broadcast IPI through tlb_remove_table_sync_one(),
just like we do in khugepaged when removing page tables for a THP
collapse.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-06-28
In the Linux kernel, the following vulnerability has been resolved:
net: ch9200: fix uninitialised access during mii_nway_restart
In mii_nway_restart() the code attempts to call
mii->mdio_read which is ch9200_mdio_read(). ch9200_mdio_read()
utilises a local buffer called "buff", which is initialised
with control_read(). However "buff" is conditionally
initialised inside control_read():
if (err == size) {
memcpy(data, buf, size);
}
If the condition of "err == size" is not met, then
"buff" remains uninitialised. Once this happens the
uninitialised "buff" is accessed and returned during
ch9200_mdio_read():
return (buff[0] | buff[1] << 8);
The problem stems from the fact that ch9200_mdio_read()
ignores the return value of control_read(), leading to
uinit-access of "buff".
To fix this we should check the return value of
control_read() and return early on error.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-06-28
In the Linux kernel, the following vulnerability has been resolved:
mm/hugetlb: unshare page tables during VMA split, not before
Currently, __split_vma() triggers hugetlb page table unsharing through
vm_ops->may_split(). This happens before the VMA lock and rmap locks are
taken - which is too early, it allows racing VMA-locked page faults in our
process and racing rmap walks from other processes to cause page tables to
be shared again before we actually perform the split.
Fix it by explicitly calling into the hugetlb unshare logic from
__split_vma() in the same place where THP splitting also happens. At that
point, both the VMA and the rmap(s) are write-locked.
An annoying detail is that we can now call into the helper
hugetlb_unshare_pmds() from two different locking contexts:
1. from hugetlb_split(), holding:
- mmap lock (exclusively)
- VMA lock
- file rmap lock (exclusively)
2. hugetlb_unshare_all_pmds(), which I think is designed to be able to
call us with only the mmap lock held (in shared mode), but currently
only runs while holding mmap lock (exclusively) and VMA lock
Backporting note:
This commit fixes a racy protection that was introduced in commit
b30c14cd6102 ("hugetlb: unshare some PMDs when splitting VMAs"); that
commit claimed to fix an issue introduced in 5.13, but it should actually
also go all the way back.
[jannh@google.com: v2]
CVSS Score
5.5
EPSS Score
0.0
Published
2025-06-28