High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
eventpoll: Fix semi-unbounded recursion
Ensure that epoll instances can never form a graph deeper than
EP_MAX_NESTS+1 links.
Currently, ep_loop_check_proc() ensures that the graph is loop-free and
does some recursion depth checks, but those recursion depth checks don't
limit the depth of the resulting tree for two reasons:
- They don't look upwards in the tree.
- If there are multiple downwards paths of different lengths, only one of
the paths is actually considered for the depth check since commit
28d82dc1c4ed ("epoll: limit paths").
Essentially, the current recursion depth check in ep_loop_check_proc() just
serves to prevent it from recursing too deeply while checking for loops.
A more thorough check is done in reverse_path_check() after the new graph
edge has already been created; this checks, among other things, that no
paths going upwards from any non-epoll file with a length of more than 5
edges exist. However, this check does not apply to non-epoll files.
As a result, it is possible to recurse to a depth of at least roughly 500,
tested on v6.15. (I am unsure if deeper recursion is possible; and this may
have changed with commit 8c44dac8add7 ("eventpoll: Fix priority inversion
problem").)
To fix it:
1. In ep_loop_check_proc(), note the subtree depth of each visited node,
and use subtree depths for the total depth calculation even when a subtree
has already been visited.
2. Add ep_get_upwards_depth_proc() for similarly determining the maximum
depth of an upwards walk.
3. In ep_loop_check(), use these values to limit the total path length
between epoll nodes to EP_MAX_NESTS edges.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.6
In the Linux kernel, the following vulnerability has been resolved:
bpf, ktls: Fix data corruption when using bpf_msg_pop_data() in ktls
When sending plaintext data, we initially calculated the corresponding
ciphertext length. However, if we later reduced the plaintext data length
via socket policy, we failed to recalculate the ciphertext length.
This results in transmitting buffers containing uninitialized data during
ciphertext transmission.
This causes uninitialized bytes to be appended after a complete
"Application Data" packet, leading to errors on the receiving end when
parsing TLS record.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
bpf: handle jset (if a & b ...) as a jump in CFG computation
BPF_JSET is a conditional jump and currently verifier.c:can_jump()
does not know about that. This can lead to incorrect live registers
and SCC computation.
E.g. in the following example:
1: r0 = 1;
2: r2 = 2;
3: if r1 & 0x7 goto +1;
4: exit;
5: r0 = r2;
6: exit;
W/o this fix insn_successors(3) will return only (4), a jump to (5)
would be missed and r2 won't be marked as alive at (3).
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: rtl818x: Kill URBs before clearing tx status queue
In rtl8187_stop() move the call of usb_kill_anchored_urbs() before clearing
b_tx_status.queue. This change prevents callbacks from using already freed
skb due to anchor was not killed before freeing such skb.
BUG: kernel NULL pointer dereference, address: 0000000000000080
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: Oops: 0000 [#1] SMP NOPTI
CPU: 7 UID: 0 PID: 0 Comm: swapper/7 Not tainted 6.15.0 #8 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
RIP: 0010:ieee80211_tx_status_irqsafe+0x21/0xc0 [mac80211]
Call Trace:
<IRQ>
rtl8187_tx_cb+0x116/0x150 [rtl8187]
__usb_hcd_giveback_urb+0x9d/0x120
usb_giveback_urb_bh+0xbb/0x140
process_one_work+0x19b/0x3c0
bh_worker+0x1a7/0x210
tasklet_action+0x10/0x30
handle_softirqs+0xf0/0x340
__irq_exit_rcu+0xcd/0xf0
common_interrupt+0x85/0xa0
</IRQ>
Tested on RTL8187BvE device.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: clear initialized flag for deinit-ed srng lists
In a number of cases we see kernel panics on resume due
to ath11k kernel page fault, which happens under the
following circumstances:
1) First ath11k_hal_dump_srng_stats() call
Last interrupt received for each group:
ath11k_pci 0000:01:00.0: group_id 0 22511ms before
ath11k_pci 0000:01:00.0: group_id 1 14440788ms before
[..]
ath11k_pci 0000:01:00.0: failed to receive control response completion, polling..
ath11k_pci 0000:01:00.0: Service connect timeout
ath11k_pci 0000:01:00.0: failed to connect to HTT: -110
ath11k_pci 0000:01:00.0: failed to start core: -110
ath11k_pci 0000:01:00.0: firmware crashed: MHI_CB_EE_RDDM
ath11k_pci 0000:01:00.0: already resetting count 2
ath11k_pci 0000:01:00.0: failed to wait wlan mode request (mode 4): -110
ath11k_pci 0000:01:00.0: qmi failed to send wlan mode off: -110
ath11k_pci 0000:01:00.0: failed to reconfigure driver on crash recovery
[..]
2) At this point reconfiguration fails (we have 2 resets) and
ath11k_core_reconfigure_on_crash() calls ath11k_hal_srng_deinit()
which destroys srng lists. However, it does not reset per-list
->initialized flag.
3) Second ath11k_hal_dump_srng_stats() call sees stale ->initialized
flag and attempts to dump srng stats:
Last interrupt received for each group:
ath11k_pci 0000:01:00.0: group_id 0 66785ms before
ath11k_pci 0000:01:00.0: group_id 1 14485062ms before
ath11k_pci 0000:01:00.0: group_id 2 14485062ms before
ath11k_pci 0000:01:00.0: group_id 3 14485062ms before
ath11k_pci 0000:01:00.0: group_id 4 14780845ms before
ath11k_pci 0000:01:00.0: group_id 5 14780845ms before
ath11k_pci 0000:01:00.0: group_id 6 14485062ms before
ath11k_pci 0000:01:00.0: group_id 7 66814ms before
ath11k_pci 0000:01:00.0: group_id 8 68997ms before
ath11k_pci 0000:01:00.0: group_id 9 67588ms before
ath11k_pci 0000:01:00.0: group_id 10 69511ms before
BUG: unable to handle page fault for address: ffffa007404eb010
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 100000067 P4D 100000067 PUD 10022d067 PMD 100b01067 PTE 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
RIP: 0010:ath11k_hal_dump_srng_stats+0x2b4/0x3b0 [ath11k]
Call Trace:
<TASK>
? __die_body+0xae/0xb0
? page_fault_oops+0x381/0x3e0
? exc_page_fault+0x69/0xa0
? asm_exc_page_fault+0x22/0x30
? ath11k_hal_dump_srng_stats+0x2b4/0x3b0 [ath11k (HASH:6cea 4)]
ath11k_qmi_driver_event_work+0xbd/0x1050 [ath11k (HASH:6cea 4)]
worker_thread+0x389/0x930
kthread+0x149/0x170
Clear per-list ->initialized flag in ath11k_hal_srng_deinit().
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7925: fix off by one in mt7925_mcu_hw_scan()
The ssid->ssids[] and sreq->ssids[] arrays have MT7925_RNR_SCAN_MAX_BSSIDS
elements so this >= needs to be > to prevent an out of bounds access.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7996: Fix possible OOB access in mt7996_tx()
Fis possible Out-Of-Boundary access in mt7996_tx routine if link_id is
set to IEEE80211_LINK_UNSPECIFIED
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix use-after-free in amdgpu_userq_suspend+0x51a/0x5a0
[ +0.000020] BUG: KASAN: slab-use-after-free in amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu]
[ +0.000817] Read of size 8 at addr ffff88812eec8c58 by task amd_pci_unplug/1733
[ +0.000027] CPU: 10 UID: 0 PID: 1733 Comm: amd_pci_unplug Tainted: G W 6.14.0+ #2
[ +0.000009] Tainted: [W]=WARN
[ +0.000003] Hardware name: ASUS System Product Name/ROG STRIX B550-F GAMING (WI-FI), BIOS 1401 12/03/2020
[ +0.000004] Call Trace:
[ +0.000004] <TASK>
[ +0.000003] dump_stack_lvl+0x76/0xa0
[ +0.000011] print_report+0xce/0x600
[ +0.000009] ? srso_return_thunk+0x5/0x5f
[ +0.000006] ? kasan_complete_mode_report_info+0x76/0x200
[ +0.000007] ? kasan_addr_to_slab+0xd/0xb0
[ +0.000006] ? amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu]
[ +0.000707] kasan_report+0xbe/0x110
[ +0.000006] ? amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu]
[ +0.000541] __asan_report_load8_noabort+0x14/0x30
[ +0.000005] amdgpu_userq_suspend+0x51a/0x5a0 [amdgpu]
[ +0.000535] ? stop_cpsch+0x396/0x600 [amdgpu]
[ +0.000556] ? stop_cpsch+0x429/0x600 [amdgpu]
[ +0.000536] ? __pfx_amdgpu_userq_suspend+0x10/0x10 [amdgpu]
[ +0.000536] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? kgd2kfd_suspend+0x132/0x1d0 [amdgpu]
[ +0.000542] amdgpu_device_fini_hw+0x581/0xe90 [amdgpu]
[ +0.000485] ? down_write+0xbb/0x140
[ +0.000007] ? __mutex_unlock_slowpath.constprop.0+0x317/0x360
[ +0.000005] ? __pfx_amdgpu_device_fini_hw+0x10/0x10 [amdgpu]
[ +0.000482] ? __kasan_check_write+0x14/0x30
[ +0.000004] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? up_write+0x55/0xb0
[ +0.000007] ? srso_return_thunk+0x5/0x5f
[ +0.000005] ? blocking_notifier_chain_unregister+0x6c/0xc0
[ +0.000008] amdgpu_driver_unload_kms+0x69/0x90 [amdgpu]
[ +0.000484] amdgpu_pci_remove+0x93/0x130 [amdgpu]
[ +0.000482] pci_device_remove+0xae/0x1e0
[ +0.000008] device_remove+0xc7/0x180
[ +0.000008] device_release_driver_internal+0x3d4/0x5a0
[ +0.000007] device_release_driver+0x12/0x20
[ +0.000004] pci_stop_bus_device+0x104/0x150
[ +0.000006] pci_stop_and_remove_bus_device_locked+0x1b/0x40
[ +0.000005] remove_store+0xd7/0xf0
[ +0.000005] ? __pfx_remove_store+0x10/0x10
[ +0.000006] ? __pfx__copy_from_iter+0x10/0x10
[ +0.000006] ? __pfx_dev_attr_store+0x10/0x10
[ +0.000006] dev_attr_store+0x3f/0x80
[ +0.000006] sysfs_kf_write+0x125/0x1d0
[ +0.000004] ? srso_return_thunk+0x5/0x5f
[ +0.000005] ? __kasan_check_write+0x14/0x30
[ +0.000005] kernfs_fop_write_iter+0x2ea/0x490
[ +0.000005] ? rw_verify_area+0x70/0x420
[ +0.000005] ? __pfx_kernfs_fop_write_iter+0x10/0x10
[ +0.000006] vfs_write+0x90d/0xe70
[ +0.000005] ? srso_return_thunk+0x5/0x5f
[ +0.000005] ? __pfx_vfs_write+0x10/0x10
[ +0.000004] ? local_clock+0x15/0x30
[ +0.000008] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? __kasan_slab_free+0x5f/0x80
[ +0.000005] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? __kasan_check_read+0x11/0x20
[ +0.000004] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? fdget_pos+0x1d3/0x500
[ +0.000007] ksys_write+0x119/0x220
[ +0.000005] ? putname+0x1c/0x30
[ +0.000006] ? __pfx_ksys_write+0x10/0x10
[ +0.000007] __x64_sys_write+0x72/0xc0
[ +0.000006] x64_sys_call+0x18ab/0x26f0
[ +0.000006] do_syscall_64+0x7c/0x170
[ +0.000004] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? __pfx___x64_sys_openat+0x10/0x10
[ +0.000006] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? __kasan_check_read+0x11/0x20
[ +0.000003] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? fpregs_assert_state_consistent+0x21/0xb0
[ +0.000006] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? syscall_exit_to_user_mode+0x4e/0x240
[ +0.000005] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? do_syscall_64+0x88/0x170
[ +0.000003] ? srso_return_thunk+0x5/0x5f
[ +0.000004] ? irqentry_exit+0x43/0x50
[ +0.000004] ? srso_return_thunk+0x5
---truncated---
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
drm/panthor: Fix UAF in panthor_gem_create_with_handle() debugfs code
The object is potentially already gone after the drm_gem_object_put().
In general the object should be fully constructed before calling
drm_gem_handle_create(), except the debugfs tracking uses a separate
lock and list and separate flag to denotate whether the object is
actually initialized.
Since I'm touching this all anyway simplify this by only adding the
object to the debugfs when it's ready for that, which allows us to
delete that separate flag. panthor_gem_debugfs_bo_rm() already checks
whether we've actually been added to the list or this is some error
path cleanup.
v2: Fix build issues for !CONFIG_DEBUGFS (Adrián)
v3: Add linebreak and remove outdated comment (Liviu)
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
xen: fix UAF in dmabuf_exp_from_pages()
[dma_buf_fd() fixes; no preferences regarding the tree it goes through -
up to xen folks]
As soon as we'd inserted a file reference into descriptor table, another
thread could close it. That's fine for the case when all we are doing is
returning that descriptor to userland (it's a race, but it's a userland
race and there's nothing the kernel can do about it). However, if we
follow fd_install() with any kind of access to objects that would be
destroyed on close (be it the struct file itself or anything destroyed
by its ->release()), we have a UAF.
dma_buf_fd() is a combination of reserving a descriptor and fd_install().
gntdev dmabuf_exp_from_pages() calls it and then proceeds to access the
objects destroyed on close - starting with gntdev_dmabuf itself.
Fix that by doing reserving descriptor before anything else and do
fd_install() only when everything had been set up.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Fix UAF on sva unbind with pending IOPFs
Commit 17fce9d2336d ("iommu/vt-d: Put iopf enablement in domain attach
path") disables IOPF on device by removing the device from its IOMMU's
IOPF queue when the last IOPF-capable domain is detached from the device.
Unfortunately, it did this in a wrong place where there are still pending
IOPFs. As a result, a use-after-free error is potentially triggered and
eventually a kernel panic with a kernel trace similar to the following:
refcount_t: underflow; use-after-free.
WARNING: CPU: 3 PID: 313 at lib/refcount.c:28 refcount_warn_saturate+0xd8/0xe0
Workqueue: iopf_queue/dmar0-iopfq iommu_sva_handle_iopf
Call Trace:
<TASK>
iopf_free_group+0xe/0x20
process_one_work+0x197/0x3d0
worker_thread+0x23a/0x350
? rescuer_thread+0x4a0/0x4a0
kthread+0xf8/0x230
? finish_task_switch.isra.0+0x81/0x260
? kthreads_online_cpu+0x110/0x110
? kthreads_online_cpu+0x110/0x110
ret_from_fork+0x13b/0x170
? kthreads_online_cpu+0x110/0x110
ret_from_fork_asm+0x11/0x20
</TASK>
---[ end trace 0000000000000000 ]---
The intel_pasid_tear_down_entry() function is responsible for blocking
hardware from generating new page faults and flushing all in-flight
ones. Therefore, moving iopf_for_domain_remove() after this function
should resolve this.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sync: fix double free in 'hci_discovery_filter_clear()'
Function 'hci_discovery_filter_clear()' frees 'uuids' array and then
sets it to NULL. There is a tiny chance of the following race:
'hci_cmd_sync_work()'
'update_passive_scan_sync()'
'hci_update_passive_scan_sync()'
'hci_discovery_filter_clear()'
kfree(uuids);
<-------------------------preempted-------------------------------->
'start_service_discovery()'
'hci_discovery_filter_clear()'
kfree(uuids); // DOUBLE FREE
<-------------------------preempted-------------------------------->
uuids = NULL;
To fix it let's add locking around 'kfree()' call and NULL pointer
assignment. Otherwise the following backtrace fires:
[ ] ------------[ cut here ]------------
[ ] kernel BUG at mm/slub.c:547!
[ ] Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
[ ] CPU: 3 UID: 0 PID: 246 Comm: bluetoothd Tainted: G O 6.12.19-kernel #1
[ ] Tainted: [O]=OOT_MODULE
[ ] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ ] pc : __slab_free+0xf8/0x348
[ ] lr : __slab_free+0x48/0x348
...
[ ] Call trace:
[ ] __slab_free+0xf8/0x348
[ ] kfree+0x164/0x27c
[ ] start_service_discovery+0x1d0/0x2c0
[ ] hci_sock_sendmsg+0x518/0x924
[ ] __sock_sendmsg+0x54/0x60
[ ] sock_write_iter+0x98/0xf8
[ ] do_iter_readv_writev+0xe4/0x1c8
[ ] vfs_writev+0x128/0x2b0
[ ] do_writev+0xfc/0x118
[ ] __arm64_sys_writev+0x20/0x2c
[ ] invoke_syscall+0x68/0xf0
[ ] el0_svc_common.constprop.0+0x40/0xe0
[ ] do_el0_svc+0x1c/0x28
[ ] el0_svc+0x30/0xd0
[ ] el0t_64_sync_handler+0x100/0x12c
[ ] el0t_64_sync+0x194/0x198
[ ] Code: 8b0002e6 eb17031f 54fffbe1 d503201f (d4210000)
[ ] ---[ end trace 0000000000000000 ]---
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_devcd_dump: fix out-of-bounds via dev_coredumpv
Currently both dev_coredumpv and skb_put_data in hci_devcd_dump use
hdev->dump.head. However, dev_coredumpv can free the buffer. From
dev_coredumpm_timeout documentation, which is used by dev_coredumpv:
> Creates a new device coredump for the given device. If a previous one hasn't
> been read yet, the new coredump is discarded. The data lifetime is determined
> by the device coredump framework and when it is no longer needed the @free
> function will be called to free the data.
If the data has not been read by the userspace yet, dev_coredumpv will
discard new buffer, freeing hdev->dump.head. This leads to
vmalloc-out-of-bounds error when skb_put_data tries to access
hdev->dump.head.
A crash report from syzbot illustrates this:
==================================================================
BUG: KASAN: vmalloc-out-of-bounds in skb_put_data
include/linux/skbuff.h:2752 [inline]
BUG: KASAN: vmalloc-out-of-bounds in hci_devcd_dump+0x142/0x240
net/bluetooth/coredump.c:258
Read of size 140 at addr ffffc90004ed5000 by task kworker/u9:2/5844
CPU: 1 UID: 0 PID: 5844 Comm: kworker/u9:2 Not tainted
6.14.0-syzkaller-10892-g4e82c87058f4 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 02/12/2025
Workqueue: hci0 hci_devcd_timeout
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
check_region_inline mm/kasan/generic.c:183 [inline]
kasan_check_range+0xef/0x1a0 mm/kasan/generic.c:189
__asan_memcpy+0x23/0x60 mm/kasan/shadow.c:105
skb_put_data include/linux/skbuff.h:2752 [inline]
hci_devcd_dump+0x142/0x240 net/bluetooth/coredump.c:258
hci_devcd_timeout+0xb5/0x2e0 net/bluetooth/coredump.c:413
process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
process_scheduled_works kernel/workqueue.c:3319 [inline]
worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
kthread+0x3c2/0x780 kernel/kthread.c:464
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
The buggy address ffffc90004ed5000 belongs to a vmalloc virtual mapping
Memory state around the buggy address:
ffffc90004ed4f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc90004ed4f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc90004ed5000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
^
ffffc90004ed5080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
ffffc90004ed5100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================
To avoid this issue, reorder dev_coredumpv to be called after
skb_put_data that does not free the data.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Remove skb secpath if xfrm state is not found
Hardware returns a unique identifier for a decrypted packet's xfrm
state, this state is looked up in an xarray. However, the state might
have been freed by the time of this lookup.
Currently, if the state is not found, only a counter is incremented.
The secpath (sp) extension on the skb is not removed, resulting in
sp->len becoming 0.
Subsequently, functions like __xfrm_policy_check() attempt to access
fields such as xfrm_input_state(skb)->xso.type (which dereferences
sp->xvec[sp->len - 1]) without first validating sp->len. This leads to
a crash when dereferencing an invalid state pointer.
This patch prevents the crash by explicitly removing the secpath
extension from the skb if the xfrm state is not found after hardware
decryption. This ensures downstream functions do not operate on a
zero-length secpath.
BUG: unable to handle page fault for address: ffffffff000002c8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 282e067 P4D 282e067 PUD 0
Oops: Oops: 0000 [#1] SMP
CPU: 12 UID: 0 PID: 0 Comm: swapper/12 Not tainted 6.15.0-rc7_for_upstream_min_debug_2025_05_27_22_44 #1 NONE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:__xfrm_policy_check+0x61a/0xa30
Code: b6 77 7f 83 e6 02 74 14 4d 8b af d8 00 00 00 41 0f b6 45 05 c1 e0 03 48 98 49 01 c5 41 8b 45 00 83 e8 01 48 98 49 8b 44 c5 10 <0f> b6 80 c8 02 00 00 83 e0 0c 3c 04 0f 84 0c 02 00 00 31 ff 80 fa
RSP: 0018:ffff88885fb04918 EFLAGS: 00010297
RAX: ffffffff00000000 RBX: 0000000000000002 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffffff8311af80 R08: 0000000000000020 R09: 00000000c2eda353
R10: ffff88812be2bbc8 R11: 000000001faab533 R12: ffff88885fb049c8
R13: ffff88812be2bbc8 R14: 0000000000000000 R15: ffff88811896ae00
FS: 0000000000000000(0000) GS:ffff8888dca82000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffff000002c8 CR3: 0000000243050002 CR4: 0000000000372eb0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
? try_to_wake_up+0x108/0x4c0
? udp4_lib_lookup2+0xbe/0x150
? udp_lib_lport_inuse+0x100/0x100
? __udp4_lib_lookup+0x2b0/0x410
__xfrm_policy_check2.constprop.0+0x11e/0x130
udp_queue_rcv_one_skb+0x1d/0x530
udp_unicast_rcv_skb+0x76/0x90
__udp4_lib_rcv+0xa64/0xe90
ip_protocol_deliver_rcu+0x20/0x130
ip_local_deliver_finish+0x75/0xa0
ip_local_deliver+0xc1/0xd0
? ip_protocol_deliver_rcu+0x130/0x130
ip_sublist_rcv+0x1f9/0x240
? ip_rcv_finish_core+0x430/0x430
ip_list_rcv+0xfc/0x130
__netif_receive_skb_list_core+0x181/0x1e0
netif_receive_skb_list_internal+0x200/0x360
? mlx5e_build_rx_skb+0x1bc/0xda0 [mlx5_core]
gro_receive_skb+0xfd/0x210
mlx5e_handle_rx_cqe_mpwrq+0x141/0x280 [mlx5_core]
mlx5e_poll_rx_cq+0xcc/0x8e0 [mlx5_core]
? mlx5e_handle_rx_dim+0x91/0xd0 [mlx5_core]
mlx5e_napi_poll+0x114/0xab0 [mlx5_core]
__napi_poll+0x25/0x170
net_rx_action+0x32d/0x3a0
? mlx5_eq_comp_int+0x8d/0x280 [mlx5_core]
? notifier_call_chain+0x33/0xa0
handle_softirqs+0xda/0x250
irq_exit_rcu+0x6d/0xc0
common_interrupt+0x81/0xa0
</IRQ>
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
bpf, arm64: Fix fp initialization for exception boundary
In the ARM64 BPF JIT when prog->aux->exception_boundary is set for a BPF
program, find_used_callee_regs() is not called because for a program
acting as exception boundary, all callee saved registers are saved.
find_used_callee_regs() sets `ctx->fp_used = true;` when it sees FP
being used in any of the instructions.
For programs acting as exception boundary, ctx->fp_used remains false
even if frame pointer is used by the program and therefore, FP is not
set-up for such programs in the prologue. This can cause the kernel to
crash due to a pagefault.
Fix it by setting ctx->fp_used = true for exception boundary programs as
fp is always saved in such programs.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7
In the Linux kernel, the following vulnerability has been resolved:
padata: Fix pd UAF once and for all
There is a race condition/UAF in padata_reorder that goes back
to the initial commit. A reference count is taken at the start
of the process in padata_do_parallel, and released at the end in
padata_serial_worker.
This reference count is (and only is) required for padata_replace
to function correctly. If padata_replace is never called then
there is no issue.
In the function padata_reorder which serves as the core of padata,
as soon as padata is added to queue->serial.list, and the associated
spin lock released, that padata may be processed and the reference
count on pd would go away.
Fix this by getting the next padata before the squeue->serial lock
is released.
In order to make this possible, simplify padata_reorder by only
calling it once the next padata arrives.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
RDMA/hns: Fix double destruction of rsv_qp
rsv_qp may be double destroyed in error flow, first in free_mr_init(),
and then in hns_roce_exit(). Fix it by moving the free_mr_init() call
into hns_roce_v2_init().
list_del corruption, ffff589732eb9b50->next is LIST_POISON1 (dead000000000100)
WARNING: CPU: 8 PID: 1047115 at lib/list_debug.c:53 __list_del_entry_valid+0x148/0x240
...
Call trace:
__list_del_entry_valid+0x148/0x240
hns_roce_qp_remove+0x4c/0x3f0 [hns_roce_hw_v2]
hns_roce_v2_destroy_qp_common+0x1dc/0x5f4 [hns_roce_hw_v2]
hns_roce_v2_destroy_qp+0x22c/0x46c [hns_roce_hw_v2]
free_mr_exit+0x6c/0x120 [hns_roce_hw_v2]
hns_roce_v2_exit+0x170/0x200 [hns_roce_hw_v2]
hns_roce_exit+0x118/0x350 [hns_roce_hw_v2]
__hns_roce_hw_v2_init_instance+0x1c8/0x304 [hns_roce_hw_v2]
hns_roce_hw_v2_reset_notify_init+0x170/0x21c [hns_roce_hw_v2]
hns_roce_hw_v2_reset_notify+0x6c/0x190 [hns_roce_hw_v2]
hclge_notify_roce_client+0x6c/0x160 [hclge]
hclge_reset_rebuild+0x150/0x5c0 [hclge]
hclge_reset+0x10c/0x140 [hclge]
hclge_reset_subtask+0x80/0x104 [hclge]
hclge_reset_service_task+0x168/0x3ac [hclge]
hclge_service_task+0x50/0x100 [hclge]
process_one_work+0x250/0x9a0
worker_thread+0x324/0x990
kthread+0x190/0x210
ret_from_fork+0x10/0x18
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix inode use after free in ext4_end_io_rsv_work()
In ext4_io_end_defer_completion(), check if io_end->list_vec is empty to
avoid adding an io_end that requires no conversion to the
i_rsv_conversion_list, which in turn prevents starting an unnecessary
worker. An ext4_emergency_state() check is also added to avoid attempting
to abort the journal in an emergency state.
Additionally, ext4_put_io_end_defer() is refactored to call
ext4_io_end_defer_completion() directly instead of being open-coded.
This also prevents starting an unnecessary worker when EXT4_IO_END_FAILED
is set but data_err=abort is not enabled.
This ensures that the check in ext4_put_io_end_defer() is consistent with
the check in ext4_end_bio(). Otherwise, we might add an io_end to the
i_rsv_conversion_list and then call ext4_finish_bio(), after which the
inode could be freed before ext4_end_io_rsv_work() is called, triggering
a use-after-free issue.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix KMSAN uninit-value in extent_info usage
KMSAN reported a use of uninitialized value in `__is_extent_mergeable()`
and `__is_back_mergeable()` via the read extent tree path.
The root cause is that `get_read_extent_info()` only initializes three
fields (`fofs`, `blk`, `len`) of `struct extent_info`, leaving the
remaining fields uninitialized. This leads to undefined behavior
when those fields are accessed later, especially during
extent merging.
Fix it by zero-initializing the `extent_info` struct before population.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid UAF in f2fs_sync_inode_meta()
syzbot reported an UAF issue as below: [1] [2]
[1] https://syzkaller.appspot.com/text?tag=CrashReport&x=16594c60580000
==================================================================
BUG: KASAN: use-after-free in __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
Read of size 8 at addr ffff888100567dc8 by task kworker/u4:0/8
CPU: 1 PID: 8 Comm: kworker/u4:0 Tainted: G W 6.1.129-syzkaller-00017-g642656a36791 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x151/0x1b7 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0x158/0x4e0 mm/kasan/report.c:427
kasan_report+0x13c/0x170 mm/kasan/report.c:531
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
__list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
__list_del_entry include/linux/list.h:134 [inline]
list_del_init include/linux/list.h:206 [inline]
f2fs_inode_synced+0x100/0x2e0 fs/f2fs/super.c:1553
f2fs_update_inode+0x72/0x1c40 fs/f2fs/inode.c:588
f2fs_update_inode_page+0x135/0x170 fs/f2fs/inode.c:706
f2fs_write_inode+0x416/0x790 fs/f2fs/inode.c:734
write_inode fs/fs-writeback.c:1460 [inline]
__writeback_single_inode+0x4cf/0xb80 fs/fs-writeback.c:1677
writeback_sb_inodes+0xb32/0x1910 fs/fs-writeback.c:1903
__writeback_inodes_wb+0x118/0x3f0 fs/fs-writeback.c:1974
wb_writeback+0x3da/0xa00 fs/fs-writeback.c:2081
wb_check_background_flush fs/fs-writeback.c:2151 [inline]
wb_do_writeback fs/fs-writeback.c:2239 [inline]
wb_workfn+0xbba/0x1030 fs/fs-writeback.c:2266
process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299
worker_thread+0xa60/0x1260 kernel/workqueue.c:2446
kthread+0x26d/0x300 kernel/kthread.c:386
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Allocated by task 298:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:333
kasan_slab_alloc include/linux/kasan.h:202 [inline]
slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:768
slab_alloc_node mm/slub.c:3421 [inline]
slab_alloc mm/slub.c:3431 [inline]
__kmem_cache_alloc_lru mm/slub.c:3438 [inline]
kmem_cache_alloc_lru+0x102/0x270 mm/slub.c:3454
alloc_inode_sb include/linux/fs.h:3255 [inline]
f2fs_alloc_inode+0x2d/0x350 fs/f2fs/super.c:1437
alloc_inode fs/inode.c:261 [inline]
iget_locked+0x18c/0x7e0 fs/inode.c:1373
f2fs_iget+0x55/0x4ca0 fs/f2fs/inode.c:486
f2fs_lookup+0x3c1/0xb50 fs/f2fs/namei.c:484
__lookup_slow+0x2b9/0x3e0 fs/namei.c:1689
lookup_slow+0x5a/0x80 fs/namei.c:1706
walk_component+0x2e7/0x410 fs/namei.c:1997
lookup_last fs/namei.c:2454 [inline]
path_lookupat+0x16d/0x450 fs/namei.c:2478
filename_lookup+0x251/0x600 fs/namei.c:2507
vfs_statx+0x107/0x4b0 fs/stat.c:229
vfs_fstatat fs/stat.c:267 [inline]
vfs_lstat include/linux/fs.h:3434 [inline]
__do_sys_newlstat fs/stat.c:423 [inline]
__se_sys_newlstat+0xda/0x7c0 fs/stat.c:417
__x64_sys_newlstat+0x5b/0x70 fs/stat.c:417
x64_sys_call+0x52/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:7
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
Freed by task 0:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
____kasan_slab_free+0x131/0x180 mm/kasan/common.c:241
__kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
kasan_slab_free include/linux/kasan.h:178 [inline]
slab_free_hook mm/slub.c:1745 [inline]
slab_free_freelist_hook mm/slub.c:1771 [inline]
slab_free mm/slub.c:3686 [inline]
kmem_cache_free+0x
---truncated---
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid panic in f2fs_evict_inode
As syzbot [1] reported as below:
R10: 0000000000000100 R11: 0000000000000206 R12: 00007ffe17473450
R13: 00007f28b1c10854 R14: 000000000000dae5 R15: 00007ffe17474520
</TASK>
---[ end trace 0000000000000000 ]---
==================================================================
BUG: KASAN: use-after-free in __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
Read of size 8 at addr ffff88812d962278 by task syz-executor/564
CPU: 1 PID: 564 Comm: syz-executor Tainted: G W 6.1.129-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack+0x21/0x24 lib/dump_stack.c:88
dump_stack_lvl+0xee/0x158 lib/dump_stack.c:106
print_address_description+0x71/0x210 mm/kasan/report.c:316
print_report+0x4a/0x60 mm/kasan/report.c:427
kasan_report+0x122/0x150 mm/kasan/report.c:531
__asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
__list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
__list_del_entry include/linux/list.h:134 [inline]
list_del_init include/linux/list.h:206 [inline]
f2fs_inode_synced+0xf7/0x2e0 fs/f2fs/super.c:1531
f2fs_update_inode+0x74/0x1c40 fs/f2fs/inode.c:585
f2fs_update_inode_page+0x137/0x170 fs/f2fs/inode.c:703
f2fs_write_inode+0x4ec/0x770 fs/f2fs/inode.c:731
write_inode fs/fs-writeback.c:1460 [inline]
__writeback_single_inode+0x4a0/0xab0 fs/fs-writeback.c:1677
writeback_single_inode+0x221/0x8b0 fs/fs-writeback.c:1733
sync_inode_metadata+0xb6/0x110 fs/fs-writeback.c:2789
f2fs_sync_inode_meta+0x16d/0x2a0 fs/f2fs/checkpoint.c:1159
block_operations fs/f2fs/checkpoint.c:1269 [inline]
f2fs_write_checkpoint+0xca3/0x2100 fs/f2fs/checkpoint.c:1658
kill_f2fs_super+0x231/0x390 fs/f2fs/super.c:4668
deactivate_locked_super+0x98/0x100 fs/super.c:332
deactivate_super+0xaf/0xe0 fs/super.c:363
cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1186
__cleanup_mnt+0x19/0x20 fs/namespace.c:1193
task_work_run+0x1c6/0x230 kernel/task_work.c:203
exit_task_work include/linux/task_work.h:39 [inline]
do_exit+0x9fb/0x2410 kernel/exit.c:871
do_group_exit+0x210/0x2d0 kernel/exit.c:1021
__do_sys_exit_group kernel/exit.c:1032 [inline]
__se_sys_exit_group kernel/exit.c:1030 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1030
x64_sys_call+0x7b4/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:232
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f28b1b8e169
Code: Unable to access opcode bytes at 0x7f28b1b8e13f.
RSP: 002b:00007ffe174710a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f28b1c10879 RCX: 00007f28b1b8e169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000002 R08: 00007ffe1746ee47 R09: 00007ffe17472360
R10: 0000000000000009 R11: 0000000000000246 R12: 00007ffe17472360
R13: 00007f28b1c10854 R14: 000000000000dae5 R15: 00007ffe17474520
</TASK>
Allocated by task 569:
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
__kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook+0x4f/0x2c0 mm/slab.h:737
slab_alloc_node mm/slub.c:3398 [inline]
slab_alloc mm/slub.c:3406 [inline]
__kmem_cache_alloc_lru mm/slub.c:3413 [inline]
kmem_cache_alloc_lru+0x104/0x220 mm/slub.c:3429
alloc_inode_sb include/linux/fs.h:3245 [inline]
f2fs_alloc_inode+0x2d/0x340 fs/f2fs/super.c:1419
alloc_inode fs/inode.c:261 [inline]
iget_locked+0x186/0x880 fs/inode.c:1373
f2fs_iget+0x55/0x4c60 fs/f2fs/inode.c:483
f2fs_lookup+0x366/0xab0 fs/f2fs/namei.c:487
__lookup_slow+0x2a3/0x3d0 fs/namei.c:1690
lookup_slow+0x57/0x70 fs/namei.c:1707
walk_component+0x2e6/0x410 fs/namei
---truncated---
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.6
In the Linux kernel, the following vulnerability has been resolved:
pptp: ensure minimal skb length in pptp_xmit()
Commit aabc6596ffb3 ("net: ppp: Add bound checking for skb data
on ppp_sync_txmung") fixed ppp_sync_txmunge()
We need a similar fix in pptp_xmit(), otherwise we might
read uninit data as reported by syzbot.
BUG: KMSAN: uninit-value in pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193
pptp_xmit+0xc34/0x2720 drivers/net/ppp/pptp.c:193
ppp_channel_bridge_input drivers/net/ppp/ppp_generic.c:2290 [inline]
ppp_input+0x1d6/0xe60 drivers/net/ppp/ppp_generic.c:2314
pppoe_rcv_core+0x1e8/0x760 drivers/net/ppp/pppoe.c:379
sk_backlog_rcv+0x142/0x420 include/net/sock.h:1148
__release_sock+0x1d3/0x330 net/core/sock.c:3213
release_sock+0x6b/0x270 net/core/sock.c:3767
pppoe_sendmsg+0x15d/0xcb0 drivers/net/ppp/pppoe.c:904
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg+0x330/0x3d0 net/socket.c:727
____sys_sendmsg+0x893/0xd80 net/socket.c:2566
___sys_sendmsg+0x271/0x3b0 net/socket.c:2620
__sys_sendmmsg+0x2d9/0x7c0 net/socket.c:2709
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.3
In the Linux kernel, the following vulnerability has been resolved:
spi: cs42l43: Property entry should be a null-terminated array
The software node does not specify a count of property entries, so the
array must be null-terminated.
When unterminated, this can lead to a fault in the downstream cs35l56
amplifier driver, because the node parse walks off the end of the
array into unknown memory.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
ipv6: reject malicious packets in ipv6_gso_segment()
syzbot was able to craft a packet with very long IPv6 extension headers
leading to an overflow of skb->transport_header.
This 16bit field has a limited range.
Add skb_reset_transport_header_careful() helper and use it
from ipv6_gso_segment()
WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 skb_reset_transport_header include/linux/skbuff.h:3032 [inline]
WARNING: CPU: 0 PID: 5871 at ./include/linux/skbuff.h:3032 ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151
Modules linked in:
CPU: 0 UID: 0 PID: 5871 Comm: syz-executor211 Not tainted 6.16.0-rc6-syzkaller-g7abc678e3084 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:skb_reset_transport_header include/linux/skbuff.h:3032 [inline]
RIP: 0010:ipv6_gso_segment+0x15e2/0x21e0 net/ipv6/ip6_offload.c:151
Call Trace:
<TASK>
skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53
nsh_gso_segment+0x54a/0xe10 net/nsh/nsh.c:110
skb_mac_gso_segment+0x31c/0x640 net/core/gso.c:53
__skb_gso_segment+0x342/0x510 net/core/gso.c:124
skb_gso_segment include/net/gso.h:83 [inline]
validate_xmit_skb+0x857/0x11b0 net/core/dev.c:3950
validate_xmit_skb_list+0x84/0x120 net/core/dev.c:4000
sch_direct_xmit+0xd3/0x4b0 net/sched/sch_generic.c:329
__dev_xmit_skb net/core/dev.c:4102 [inline]
__dev_queue_xmit+0x17b6/0x3a70 net/core/dev.c:4679
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 8.2
In the Linux kernel, the following vulnerability has been resolved:
sunrpc: fix client side handling of tls alerts
A security exploit was discovered in NFS over TLS in tls_alert_recv
due to its assumption that there is valid data in the msghdr's
iterator's kvec.
Instead, this patch proposes the rework how control messages are
setup and used by sock_recvmsg().
If no control message structure is setup, kTLS layer will read and
process TLS data record types. As soon as it encounters a TLS control
message, it would return an error. At that point, NFS can setup a kvec
backed control buffer and read in the control message such as a TLS
alert. Scott found that a msg iterator can advance the kvec pointer
as a part of the copy process thus we need to revert the iterator
before calling into the tls_alert_recv.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
eth: fbnic: unlink NAPIs from queues on error to open
CI hit a UaF in fbnic in the AF_XDP portion of the queues.py test.
The UaF is in the __sk_mark_napi_id_once() call in xsk_bind(),
NAPI has been freed. Looks like the device failed to open earlier,
and we lack clearing the NAPI pointer from the queue.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
net/sched: mqprio: fix stack out-of-bounds write in tc entry parsing
TCA_MQPRIO_TC_ENTRY_INDEX is validated using
NLA_POLICY_MAX(NLA_U32, TC_QOPT_MAX_QUEUE), which allows the value
TC_QOPT_MAX_QUEUE (16). This leads to a 4-byte out-of-bounds stack
write in the fp[] array, which only has room for 16 elements (0–15).
Fix this by changing the policy to allow only up to TC_QOPT_MAX_QUEUE - 1.
Published Aug 19, 2025 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
sunrpc: fix handling of server side tls alerts
Scott Mayhew discovered a security exploit in NFS over TLS in
tls_alert_recv() due to its assumption it can read data from
the msg iterator's kvec..
kTLS implementation splits TLS non-data record payload between
the control message buffer (which includes the type such as TLS
aler or TLS cipher change) and the rest of the payload (say TLS
alert's level/description) which goes into the msg payload buffer.
This patch proposes to rework how control messages are setup and
used by sock_recvmsg().
If no control message structure is setup, kTLS layer will read and
process TLS data record types. As soon as it encounters a TLS control
message, it would return an error. At that point, NFS can setup a
kvec backed msg buffer and read in the control message such as a
TLS alert. Msg iterator can advance the kvec pointer as a part of
the copy process thus we need to revert the iterator before calling
into the tls_alert_recv.
Published Aug 19, 2025 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix Preauh_HashValue race condition
If client send multiple session setup requests to ksmbd,
Preauh_HashValue race condition could happen.
There is no need to free sess->Preauh_HashValue at session setup phase.
It can be freed together with session at connection termination phase.
Published Aug 19, 2025 · Updated Aug 5, 2026
Critical · CVSS 9.3
In the Linux kernel, the following vulnerability has been resolved:
x86/sev: Evict cache lines during SNP memory validation
An SNP cache coherency vulnerability requires a cache line eviction
mitigation when validating memory after a page state change to private.
The specific mitigation is to touch the first and last byte of each 4K
page that is being validated. There is no need to perform the mitigation
when performing a page state change to shared and rescinding validation.
CPUID bit Fn8000001F_EBX[31] defines the COHERENCY_SFW_NO CPUID bit
that, when set, indicates that the software mitigation for this
vulnerability is not needed.
Implement the mitigation and invoke it when validating memory (making it
private) and the COHERENCY_SFW_NO bit is not set, indicating the SNP
guest is vulnerable.
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget : fix use-after-free in composite_dev_cleanup()
1. In func configfs_composite_bind() -> composite_os_desc_req_prepare():
if kmalloc fails, the pointer cdev->os_desc_req will be freed but not
set to NULL. Then it will return a failure to the upper-level function.
2. in func configfs_composite_bind() -> composite_dev_cleanup():
it will checks whether cdev->os_desc_req is NULL. If it is not NULL, it
will attempt to use it.This will lead to a use-after-free issue.
BUG: KASAN: use-after-free in composite_dev_cleanup+0xf4/0x2c0
Read of size 8 at addr 0000004827837a00 by task init/1
CPU: 10 PID: 1 Comm: init Tainted: G O 5.10.97-oh #1
kasan_report+0x188/0x1cc
__asan_load8+0xb4/0xbc
composite_dev_cleanup+0xf4/0x2c0
configfs_composite_bind+0x210/0x7ac
udc_bind_to_driver+0xb4/0x1ec
usb_gadget_probe_driver+0xec/0x21c
gadget_dev_desc_UDC_store+0x264/0x27c
Published Aug 19, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
mm: fix a UAF when vma->mm is freed after vma->vm_refcnt got dropped
By inducing delays in the right places, Jann Horn created a reproducer for
a hard to hit UAF issue that became possible after VMAs were allowed to be
recycled by adding SLAB_TYPESAFE_BY_RCU to their cache.
Race description is borrowed from Jann's discovery report:
lock_vma_under_rcu() looks up a VMA locklessly with mas_walk() under
rcu_read_lock(). At that point, the VMA may be concurrently freed, and it
can be recycled by another process. vma_start_read() then increments the
vma->vm_refcnt (if it is in an acceptable range), and if this succeeds,
vma_start_read() can return a recycled VMA.
In this scenario where the VMA has been recycled, lock_vma_under_rcu()
will then detect the mismatching ->vm_mm pointer and drop the VMA through
vma_end_read(), which calls vma_refcount_put(). vma_refcount_put() drops
the refcount and then calls rcuwait_wake_up() using a copy of vma->vm_mm.
This is wrong: It implicitly assumes that the caller is keeping the VMA's
mm alive, but in this scenario the caller has no relation to the VMA's mm,
so the rcuwait_wake_up() can cause UAF.
The diagram depicting the race:
T1 T2 T3
== == ==
lock_vma_under_rcu
mas_walk
<VMA gets removed from mm>
mmap
<the same VMA is reallocated>
vma_start_read
__refcount_inc_not_zero_limited_acquire
munmap
__vma_enter_locked
refcount_add_not_zero
vma_end_read
vma_refcount_put
__refcount_dec_and_test
rcuwait_wait_event
<finish operation>
rcuwait_wake_up [UAF]
Note that rcuwait_wait_event() in T3 does not block because refcount was
already dropped by T1. At this point T3 can exit and free the mm causing
UAF in T1.
To avoid this we move vma->vm_mm verification into vma_start_read() and
grab vma->vm_mm to stabilize it before vma_refcount_put() operation.
[surenb@google.com: v3]
Published Aug 19, 2025 · Updated Aug 5, 2026
Critical · CVSS 9.4
In the Linux kernel, the following vulnerability has been resolved:
mptcp: plug races between subflow fail and subflow creation
We have races similar to the one addressed by the previous patch between
subflow failing and additional subflow creation. They are just harder to
trigger.
The solution is similar. Use a separate flag to track the condition
'socket state prevent any additional subflow creation' protected by the
fallback lock.
The socket fallback makes such flag true, and also receiving or sending
an MP_FAIL option.
The field 'allow_infinite_fallback' is now always touched under the
relevant lock, we can drop the ONCE annotation on write.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: Delay put pmc->idev in mld_del_delrec()
pmc->idev is still used in ip6_mc_clear_src(), so as mld_clear_delrec()
does, the reference should be put after ip6_mc_clear_src() return.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.3
In the Linux kernel, the following vulnerability has been resolved:
iio: adc: axp20x_adc: Add missing sentinel to AXP717 ADC channel maps
The AXP717 ADC channel maps is missing a sentinel entry at the end. This
causes a KASAN warning.
Add the missing sentinel entry.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: ti: am65-cpsw-nuss: Fix skb size by accounting for skb_shared_info
While transitioning from netdev_alloc_ip_align() to build_skb(), memory
for the "skb_shared_info" member of an "skb" was not allocated. Fix this
by allocating "PAGE_SIZE" as the skb length, accounting for the packet
length, headroom and tailroom, thereby including the required memory space
for skb_shared_info.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
net: appletalk: Fix device refcount leak in atrtr_create()
When updating an existing route entry in atrtr_create(), the old device
reference was not being released before assigning the new device,
leading to a device refcount leak. Fix this by calling dev_put() to
release the old device reference before holding the new one.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
tracing: Add down_write(trace_event_sem) when adding trace event
When a module is loaded, it adds trace events defined by the module. It
may also need to modify the modules trace printk formats to replace enum
names with their values.
If two modules are loaded at the same time, the adding of the event to the
ftrace_events list can corrupt the walking of the list in the code that is
modifying the printk format strings and crash the kernel.
The addition of the event should take the trace_event_sem for write while
it adds the new event.
Also add a lockdep_assert_held() on that semaphore in
__trace_add_event_dirs() as it iterates the list.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
net: airoha: fix potential use-after-free in airoha_npu_get()
np->name was being used after calling of_node_put(np), which
releases the node and can lead to a use-after-free bug.
Previously, of_node_put(np) was called unconditionally after
of_find_device_by_node(np), which could result in a use-after-free if
pdev is NULL.
This patch moves of_node_put(np) after the error check to ensure
the node is only released after both the error and success cases
are handled appropriately, preventing potential resource issues.
Published Aug 16, 2025 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
net: libwx: fix the using of Rx buffer DMA
The wx_rx_buffer structure contained two DMA address fields: 'dma' and
'page_dma'. However, only 'page_dma' was actually initialized and used
to program the Rx descriptor. But 'dma' was uninitialized and used in
some paths.
This could lead to undefined behavior, including DMA errors or
use-after-free, if the uninitialized 'dma' was used. Althrough such
error has not yet occurred, it is worth fixing in the code.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.8
In the Linux kernel, the following vulnerability has been resolved:
net: libwx: properly reset Rx ring descriptor
When device reset is triggered by feature changes such as toggling Rx
VLAN offload, wx->do_reset() is called to reinitialize Rx rings. The
hardware descriptor ring may retain stale values from previous sessions.
And only set the length to 0 in rx_desc[0] would result in building
malformed SKBs. Fix it to ensure a clean slate after device reset.
[ 549.186435] [ C16] ------------[ cut here ]------------
[ 549.186457] [ C16] kernel BUG at net/core/skbuff.c:2814!
[ 549.186468] [ C16] Oops: invalid opcode: 0000 [#1] SMP NOPTI
[ 549.186472] [ C16] CPU: 16 UID: 0 PID: 0 Comm: swapper/16 Kdump: loaded Not tainted 6.16.0-rc4+ #23 PREEMPT(voluntary)
[ 549.186476] [ C16] Hardware name: Micro-Star International Co., Ltd. MS-7E16/X670E GAMING PLUS WIFI (MS-7E16), BIOS 1.90 12/31/2024
[ 549.186478] [ C16] RIP: 0010:__pskb_pull_tail+0x3ff/0x510
[ 549.186484] [ C16] Code: 06 f0 ff 4f 34 74 7b 4d 8b 8c 24 c8 00 00 00 45 8b 84 24 c0 00 00 00 e9 c8 fd ff ff 48 c7 44 24 08 00 00 00 00 e9 5e fe ff ff <0f> 0b 31 c0 e9 23 90 5b ff 41 f7 c6 ff 0f 00 00 75 bf 49 8b 06 a8
[ 549.186487] [ C16] RSP: 0018:ffffb391c0640d70 EFLAGS: 00010282
[ 549.186490] [ C16] RAX: 00000000fffffff2 RBX: ffff8fe7e4d40200 RCX: 00000000fffffff2
[ 549.186492] [ C16] RDX: ffff8fe7c3a4bf8e RSI: 0000000000000180 RDI: ffff8fe7c3a4bf40
[ 549.186494] [ C16] RBP: ffffb391c0640da8 R08: ffff8fe7c3a4c0c0 R09: 000000000000000e
[ 549.186496] [ C16] R10: ffffb391c0640d88 R11: 000000000000000e R12: ffff8fe7e4d40200
[ 549.186497] [ C16] R13: 00000000fffffff2 R14: ffff8fe7fa01a000 R15: 00000000fffffff2
[ 549.186499] [ C16] FS: 0000000000000000(0000) GS:ffff8fef5ae40000(0000) knlGS:0000000000000000
[ 549.186502] [ C16] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 549.186503] [ C16] CR2: 00007f77d81d6000 CR3: 000000051a032000 CR4: 0000000000750ef0
[ 549.186505] [ C16] PKRU: 55555554
[ 549.186507] [ C16] Call Trace:
[ 549.186510] [ C16] <IRQ>
[ 549.186513] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186517] [ C16] __skb_pad+0xc7/0xf0
[ 549.186523] [ C16] wx_clean_rx_irq+0x355/0x3b0 [libwx]
[ 549.186533] [ C16] wx_poll+0x92/0x120 [libwx]
[ 549.186540] [ C16] __napi_poll+0x28/0x190
[ 549.186544] [ C16] net_rx_action+0x301/0x3f0
[ 549.186548] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186551] [ C16] ? __raw_spin_lock_irqsave+0x1e/0x50
[ 549.186554] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186557] [ C16] ? wake_up_nohz_cpu+0x35/0x160
[ 549.186559] [ C16] ? srso_alias_return_thunk+0x5/0xfbef5
[ 549.186563] [ C16] handle_softirqs+0xf9/0x2c0
[ 549.186568] [ C16] __irq_exit_rcu+0xc7/0x130
[ 549.186572] [ C16] common_interrupt+0xb8/0xd0
[ 549.186576] [ C16] </IRQ>
[ 549.186577] [ C16] <TASK>
[ 549.186579] [ C16] asm_common_interrupt+0x22/0x40
[ 549.186582] [ C16] RIP: 0010:cpuidle_enter_state+0xc2/0x420
[ 549.186585] [ C16] Code: 00 00 e8 11 0e 5e ff e8 ac f0 ff ff 49 89 c5 0f 1f 44 00 00 31 ff e8 0d ed 5c ff 45 84 ff 0f 85 40 02 00 00 fb 0f 1f 44 00 00 <45> 85 f6 0f 88 84 01 00 00 49 63 d6 48 8d 04 52 48 8d 04 82 49 8d
[ 549.186587] [ C16] RSP: 0018:ffffb391c0277e78 EFLAGS: 00000246
[ 549.186590] [ C16] RAX: ffff8fef5ae40000 RBX: 0000000000000003 RCX: 0000000000000000
[ 549.186591] [ C16] RDX: 0000007fde0faac5 RSI: ffffffff826e53f6 RDI: ffffffff826fa9b3
[ 549.186593] [ C16] RBP: ffff8fe7c3a20800 R08: 0000000000000002 R09: 0000000000000000
[ 549.186595] [ C16] R10: 0000000000000000 R11: 000000000000ffff R12: ffffffff82ed7a40
[ 549.186596] [ C16] R13: 0000007fde0faac5 R14: 0000000000000003 R15: 0000000000000000
[ 549.186601] [ C16] ? cpuidle_enter_state+0xb3/0x420
[ 549.186605] [ C16] cpuidle_en
---truncated---
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.1
In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject %p% format string in bprintf-like helpers
static const char fmt[] = "%p%";
bpf_trace_printk(fmt, sizeof(fmt));
The above BPF program isn't rejected and causes a kernel warning at
runtime:
Please remove unsupported %\x00 in format string
WARNING: CPU: 1 PID: 7244 at lib/vsprintf.c:2680 format_decode+0x49c/0x5d0
This happens because bpf_bprintf_prepare skips over the second %,
detected as punctuation, while processing %p. This patch fixes it by
not skipping over punctuation. %\x00 is then processed in the next
iteration and rejected.
Published Aug 16, 2025 · Updated Aug 5, 2026
Critical · CVSS 9.8
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix use-after-free in cifs_oplock_break
A race condition can occur in cifs_oplock_break() leading to a
use-after-free of the cinode structure when unmounting:
cifs_oplock_break()
_cifsFileInfo_put(cfile)
cifsFileInfo_put_final()
cifs_sb_deactive()
[last ref, start releasing sb]
kill_sb()
kill_anon_super()
generic_shutdown_super()
evict_inodes()
dispose_list()
evict()
destroy_inode()
call_rcu(&inode->i_rcu, i_callback)
spin_lock(&cinode->open_file_lock) <- OK
[later] i_callback()
cifs_free_inode()
kmem_cache_free(cinode)
spin_unlock(&cinode->open_file_lock) <- UAF
cifs_done_oplock_break(cinode) <- UAF
The issue occurs when umount has already released its reference to the
superblock. When _cifsFileInfo_put() calls cifs_sb_deactive(), this
releases the last reference, triggering the immediate cleanup of all
inodes under RCU. However, cifs_oplock_break() continues to access the
cinode after this point, resulting in use-after-free.
Fix this by holding an extra reference to the superblock during the
entire oplock break operation. This ensures that the superblock and
its inodes remain valid until the oplock break completes.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
ice: add NULL check in eswitch lag check
The function ice_lag_is_switchdev_running() is being called from outside of
the LAG event handler code. This results in the lag->upper_netdev being
NULL sometimes. To avoid a NULL-pointer dereference, there needs to be a
check before it is dereferenced.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix recv-recv race of completed call
If a call receives an event (such as incoming data), the call gets placed
on the socket's queue and a thread in recvmsg can be awakened to go and
process it. Once the thread has picked up the call off of the queue,
further events will cause it to be requeued, and once the socket lock is
dropped (recvmsg uses call->user_mutex to allow the socket to be used in
parallel), a second thread can come in and its recvmsg can pop the call off
the socket queue again.
In such a case, the first thread will be receiving stuff from the call and
the second thread will be blocked on call->user_mutex. The first thread
can, at this point, process both the event that it picked call for and the
event that the second thread picked the call for and may see the call
terminate - in which case the call will be "released", decoupling the call
from the user call ID assigned to it (RXRPC_USER_CALL_ID in the control
message).
The first thread will return okay, but then the second thread will wake up
holding the user_mutex and, if it sees that the call has been released by
the first thread, it will BUG thusly:
kernel BUG at net/rxrpc/recvmsg.c:474!
Fix this by just dequeuing the call and ignoring it if it is seen to be
already released. We can't tell userspace about it anyway as the user call
ID has become stale.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix the smbd_response slab to allow usercopy
The handling of received data in the smbdirect client code involves using
copy_to_iter() to copy data from the smbd_reponse struct's packet trailer
to a folioq buffer provided by netfslib that encapsulates a chunk of
pagecache.
If, however, CONFIG_HARDENED_USERCOPY=y, this will result in the checks
then performed in copy_to_iter() oopsing with something like the following:
CIFS: Attempting to mount //172.31.9.1/test
CIFS: VFS: RDMA transport established
usercopy: Kernel memory exposure attempt detected from SLUB object 'smbd_response_0000000091e24ea1' (offset 81, size 63)!
------------[ cut here ]------------
kernel BUG at mm/usercopy.c:102!
...
RIP: 0010:usercopy_abort+0x6c/0x80
...
Call Trace:
<TASK>
__check_heap_object+0xe3/0x120
__check_object_size+0x4dc/0x6d0
smbd_recv+0x77f/0xfe0 [cifs]
cifs_readv_from_socket+0x276/0x8f0 [cifs]
cifs_read_from_socket+0xcd/0x120 [cifs]
cifs_demultiplex_thread+0x7e9/0x2d50 [cifs]
kthread+0x396/0x830
ret_from_fork+0x2b8/0x3b0
ret_from_fork_asm+0x1a/0x30
The problem is that the smbd_response slab's packet field isn't marked as
being permitted for usercopy.
Fix this by passing parameters to kmem_slab_create() to indicate that
copy_to_iter() is permitted from the packet region of the smbd_response
slab objects, less the header space.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.5
In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix oops due to non-existence of prealloc backlog struct
If an AF_RXRPC service socket is opened and bound, but calls are
preallocated, then rxrpc_alloc_incoming_call() will oops because the
rxrpc_backlog struct doesn't get allocated until the first preallocation is
made.
Fix this by returning NULL from rxrpc_alloc_incoming_call() if there is no
backlog struct. This will cause the incoming call to be aborted.
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
wifi: prevent A-MSDU attacks in mesh networks
This patch is a mitigation to prevent the A-MSDU spoofing vulnerability
for mesh networks. The initial update to the IEEE 802.11 standard, in
response to the FragAttacks, missed this case (CVE-2025-27558). It can
be considered a variant of CVE-2020-24588 but for mesh networks.
This patch tries to detect if a standard MSDU was turned into an A-MSDU
by an adversary. This is done by parsing a received A-MSDU as a standard
MSDU, calculating the length of the Mesh Control header, and seeing if
the 6 bytes after this header equal the start of an rfc1042 header. If
equal, this is a strong indication of an ongoing attack attempt.
This defense was tested with mac80211_hwsim against a mesh network that
uses an empty Mesh Address Extension field, i.e., when four addresses
are used, and when using a 12-byte Mesh Address Extension field, i.e.,
when six addresses are used. Functionality of normal MSDUs and A-MSDUs
was also tested, and confirmed working, when using both an empty and
12-byte Mesh Address Extension field.
It was also tested with mac80211_hwsim that A-MSDU attacks in non-mesh
networks keep being detected and prevented.
Note that the vulnerability being patched, and the defense being
implemented, was also discussed in the following paper and in the
following IEEE 802.11 presentation:
https://papers.mathyvanhoef.com/wisec2025.pdf
https://mentor.ieee.org/802.11/dcn/25/11-25-0949-00-000m-a-msdu-mesh-spoof-protection.docx
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 8.8
In the Linux kernel, the following vulnerability has been resolved:
drm/xe/pf: Clear all LMTT pages on alloc
Our LMEM buffer objects are not cleared by default on alloc
and during VF provisioning we only setup LMTT PTEs for the
actually provisioned LMEM range. But beyond that valid range
we might leave some stale data that could either point to some
other VFs allocations or even to the PF pages.
Explicitly clear all new LMTT page to avoid the risk that a
malicious VF would try to exploit that gap.
While around add asserts to catch any undesired PTE overwrites
and low-level debug traces to track LMTT PT life-cycle.
(cherry picked from commit 3fae6918a3e27cce20ded2551f863fb05d4bef8d)
Published Aug 16, 2025 · Updated Aug 5, 2026
High · CVSS 7.3
In the Linux kernel, the following vulnerability has been resolved:
x86/sev: Use TSC_FACTOR for Secure TSC frequency calculation
When using Secure TSC, the GUEST_TSC_FREQ MSR reports a frequency based on
the nominal P0 frequency, which deviates slightly (typically ~0.2%) from
the actual mean TSC frequency due to clocking parameters.
Over extended VM uptime, this discrepancy accumulates, causing clock skew
between the hypervisor and a SEV-SNP VM, leading to early timer interrupts as
perceived by the guest.
The guest kernel relies on the reported nominal frequency for TSC-based
timekeeping, while the actual frequency set during SNP_LAUNCH_START may
differ. This mismatch results in inaccurate time calculations, causing the
guest to perceive hrtimers as firing earlier than expected.
Utilize the TSC_FACTOR from the SEV firmware's secrets page (see "Secrets
Page Format" in the SNP Firmware ABI Specification) to calculate the mean
TSC frequency, ensuring accurate timekeeping and mitigating clock skew in
SEV-SNP VMs.
Use early_ioremap_encrypted() to map the secrets page as
ioremap_encrypted() uses kmalloc() which is not available during early TSC
initialization and causes a panic.
[ bp: Drop the silly dummy var:
https://lore.kernel.org/r/20250630192726.GBaGLlHl84xIopx4Pt@fat_crate.local ]
Published Aug 16, 2025 · Updated Aug 5, 2026
