| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: tear down new links on vif update error path
When ieee80211_vif_update_links() adds new links it allocates a link
container for each and calls ieee80211_link_init() (which registers the
per-link debugfs files with file->private_data pointing into the container)
and ieee80211_link_setup(). If the subsequent drv_change_vif_links() fails,
the error path restores the old pointers and jumps to 'free', which frees
the new containers but never removes their debugfs entries or stops the
links. The debugfs files survive with file->private_data dangling at the
freed container, so a later open()+read() (e.g. link-1/txpower)
dereferences freed memory in ieee80211_if_read_link(), a use-after-free.
The removal path already dismantles links correctly via
ieee80211_tear_down_links(), which removes each link's keys and debugfs
entries and calls ieee80211_link_stop(); the add path on the error branch
does not. Commit be1ba9ed221f ("wifi: mac80211: avoid weird state in error
path") hardened this same error path for the link-removal case
(new_links == 0) but left the newly-added links' teardown unaddressed.
drv_change_vif_links() can fail at runtime on MLO drivers (internal
allocation / queue / firmware command failures).
Remove the new links' debugfs entries and stop them before freeing.
BUG: KASAN: slab-use-after-free in ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)
Read of size 8 at addr ffff888011290000 by task exploit/145
Call Trace:
...
ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)
short_proxy_read (fs/debugfs/file.c:373)
vfs_read (fs/read_write.c:572)
ksys_read (fs/read_write.c:716)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
...
Oops: general protection fault, probably for non-canonical address 0xdffffc000000000a
RIP: 0010:ieee80211_if_read_link (net/mac80211/debugfs_netdev.c:127)
Kernel panic - not syncing: Fatal exception |
| In the Linux kernel, the following vulnerability has been resolved:
ipv4: fib: free fib_alias with kfree_rcu() on insert error path
fib_table_insert() publishes new_fa into the leaf's fa_list with
fib_insert_alias() before calling the fib entry notifiers. When a
notifier fails, the error path removes new_fa with fib_remove_alias()
(hlist_del_rcu) and frees it right away with kmem_cache_free().
fib_table_lookup() walks that list under rcu_read_lock() only, so a
concurrent lookup that already reached new_fa keeps reading it after the
free:
BUG: KASAN: slab-use-after-free in fib_table_lookup (net/ipv4/fib_trie.c:1601)
Read of size 1 at addr ffff88810676d4eb by task exploit/297
Call Trace:
fib_table_lookup (net/ipv4/fib_trie.c:1601)
ip_route_output_key_hash_rcu (net/ipv4/route.c:2814)
ip_route_output_key_hash (net/ipv4/route.c:2705)
__ip4_datagram_connect (net/ipv4/datagram.c:49)
udp_connect (net/ipv4/udp.c:2144)
__sys_connect (net/socket.c:2167)
__x64_sys_connect (net/socket.c:2173)
do_syscall_64
entry_SYSCALL_64_after_hwframe
which belongs to the cache ip_fib_alias of size 56
Triggering the error path needs CAP_NET_ADMIN and a registered fib
notifier that can reject a route; a netdevsim device whose IPv4 FIB
resource is exhausted is enough.
Free new_fa with alias_free_mem_rcu(), as fib_table_delete() already
does for a fib_alias removed from the trie. |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: policy: preallocate inexact bins before xfrm_hash_rebuild reinsert
xfrm_hash_rebuild()'s first loop preallocates the bins/chains the reinsert
loop needs, so the reinsert (after hlist_del_rcu()) cannot allocate or
fail. But its guard is inverted: it skips policies with prefixlen <
threshold and preallocates for the rest.
prefixlen < threshold is exactly when policy_hash_bysel() returns NULL and
the reinsert takes the allocating xfrm_policy_inexact_insert() path. So the
loop preallocates for the exact policies (which never allocate) and skips
the inexact ones, whose bin/node is then allocated GFP_ATOMIC during
reinsert. On failure the error path only WARN_ONCE()s and continues,
leaving a poisoned bydst node; the next rebuild's hlist_del_rcu()
dereferences LIST_POISON2 and takes a GPF. Reachable under memory pressure,
deterministic via failslab.
Invert the guard so preallocation covers exactly the reinserted policies;
the reinsert then allocates nothing and cannot fail.
Crash:
Oops: general protection fault, probably for non-canonical address
0xfbd59c0000000024: 0000 [#1] SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0xdead...]
...
Workqueue: events xfrm_hash_rebuild
RIP: 0010:xfrm_hash_rebuild+0x5b3/0x1190
RAX: dead000000000122 (LIST_POISON2 + offset)
...
Call Trace:
hlist_del_rcu (include/linux/rculist.h:599)
xfrm_hash_rebuild (net/xfrm/xfrm_policy.c:1365)
process_one_work (kernel/workqueue.c:3322)
worker_thread (kernel/workqueue.c:3486)
kthread (kernel/kthread.c:436)
ret_from_fork (arch/x86/kernel/process.c:158)
ret_from_fork_asm (arch/x86/entry/entry_64.S:245)
...
Kernel panic - not syncing: Fatal exception in interrupt |
| In the Linux kernel, the following vulnerability has been resolved:
platform/x86: intel-hid: Protect ACPI notify handler against recursion
Since commit e2ffcda16290 ("ACPI: OSL: Allow Notify () handlers to run on
all CPUs") ACPI notify handlers like the intel-hid notify_handler() may
run on multiple CPU cores racing with themselves.
On convertibles and detachables (matched by DMI chassis-type 31 and 32 in
dmi_auto_add_switch[]) the SW_TABLET_MODE input device is registered
lazily from notify_handler() on the first tablet-mode event, via
intel_hid_switches_setup(). When two such events race on different CPUs
both can pass the !priv->switches check and register the priv->switches
input device twice, resulting in a duplicate sysfs entry and a subsequent
NULL pointer dereference.
This is the same class of bug fixed by commit e075c3b13a0a ("platform/x86:
intel-vbtn: Protect ACPI notify handler against recursion") for the
sibling intel-vbtn driver.
Protect intel-hid notify_handler() from racing with itself with a mutex
to fix this. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: hid-lenovo-go: cancel cfg_setup work in hid_go_cfg_remove()
hid_go_cfg_probe() initialises drvdata.go_cfg_setup and schedules it
to run 2 ms later:
INIT_DELAYED_WORK(&drvdata.go_cfg_setup, &cfg_setup);
schedule_delayed_work(&drvdata.go_cfg_setup, msecs_to_jiffies(2));
cfg_setup() dereferences drvdata.hdev to issue MCU command requests.
hid_go_cfg_remove() tears down sysfs and stops the HID device, but
never drains the delayed work. If the device is unbound within the
2 ms scheduling delay (a probe failure rolling back via remove, or a
fast rmmod after probe), the work fires after hid_destroy_device()
has dropped its reference and released the underlying hdev struct,
leaving cfg_setup() with a stale drvdata.hdev pointer.
Mirror the sibling driver hid-lenovo-go-s.c, whose hid_gos_cfg_remove()
already calls cancel_delayed_work_sync() on its analogous work, and
drain go_cfg_setup at the top of hid_go_cfg_remove(). The cancel
must come before guard(mutex)(&drvdata.cfg_mutex) because cfg_setup()
acquires that mutex; reversing the order would deadlock. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: drain bus_reset work on device removal
brcmf_fw_crashed() and the debugfs "reset" entry both schedule
drvr->bus_reset, whose callback recovers drvr through container_of()
and dereferences it. The removal path frees drvr (brcmf_free ->
wiphy_free) without draining the work, so a bus_reset callback pending
or running during removal can outlive drvr.
Cancellation cannot live in brcmf_detach() or brcmf_free(): the work
callback reaches teardown through the bus .reset op (PCIe
brcmf_pcie_reset -> brcmf_detach; SDIO brcmf_sdio_bus_reset ->
brcmf_sdiod_remove -> brcmf_free), so cancelling there would wait for
the running work and deadlock.
Add a per-bus mutex (bus_reset_lock) and route all arming through
brcmf_bus_schedule_reset(), which under the lock skips when the bus is
marked removing. Each bus remove entry calls
brcmf_bus_cancel_reset_work(), which under the same lock sets removing
and cancels the work. Holding the mutex across cancel_work_sync() makes
the set-removing + drain step atomic. Every producer reaches the arming
path from process context -- the PCIe firmware-halt notification runs in
the threaded IRQ handler (brcmf_pcie_isr_thread) and the SDIO hostmail
path runs from the data workqueue -- so the mutex is taken only in
sleepable contexts. Where applicable the remove entry first stops the
firmware-crash producer: on PCIe mask the mailbox and synchronize_irq;
on SDIO unregister the bus interrupt and cancel the data worker, which
also reports firmware halts through brcmf_fw_crashed(). The mutex is
initialized at bus allocation. The SDIO suspend power-off path frees
drvr through the same brcmf_sdiod_remove() and takes the same lock;
resume re-allows the work only on a successful re-probe.
Also guard brcmf_fw_crashed() against a NULL bus_if/drvr: it can fire
before brcmf_attach() wires up drvr, and it dereferences drvr
(bphy_err/brcmf_dev_coredump) before reaching the arming gate.
The bus_reset work is shared across buses, so the drain is applied to
every remove path: PCIe (the .reset op introduced by the Fixes commit),
SDIO (arms the same work through brcmf_fw_crashed()), and USB (via the
debugfs "reset" entry). cancel_work_sync() drains a running or pending
bus_reset work item before removal frees drvr, and patch 1/2 makes the
scratch-buffer release safe when reset teardown has already released
those DMA buffers.
This patch fixes the lifetime of the bus_reset work item itself. It does
not attempt to address the separate, pre-existing lifetime of the
asynchronous firmware completion started by the PCIe reset path. That
callback needs its own lifetime/ownership protocol and is being tracked
separately.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: arc: emac: quiesce interrupts before requesting IRQ
Normal RX/TX interrupts are enabled later, in arc_emac_open(), so probe
should not see interrupt delivery in the usual case. However, hardware may
still present stale or latched interrupt status left by firmware or the
bootloader.
If probe later unwinds after devm_request_irq() has installed the handler,
such a stale interrupt can still reach arc_emac_intr() during teardown and
race with release of the associated net_device.
Avoid that window by putting the device into a known quiescent state before
requesting the IRQ: disable all EMAC interrupt sources and clear any
pending EMAC interrupt status bits. This keeps the change hardware-focused
and minimal, while preventing spurious IRQ delivery from leftover state. |
| In the Linux kernel, the following vulnerability has been resolved:
dma-buf/udmabuf: skip redundant cpu sync to fix cacheline EEXIST warning
When CONFIG_DMA_API_DEBUG_SG is enabled, importing a udmabuf into a DRM
driver (e.g. amdgpu for video playback in GNOME Videos / Showtime)
triggers a spurious warning:
DMA-API: amdgpu 0000:03:00.0: cacheline tracking EEXIST, \
overlapping mappings aren't supported
WARNING: kernel/dma/debug.c:619 at add_dma_entry+0x473/0x5f0
The call chain is:
amdgpu_cs_ioctl
-> amdgpu_ttm_backend_bind
-> dma_buf_map_attachment
-> [udmabuf] map_udmabuf -> get_sg_table
-> dma_map_sgtable(dev, sg, direction, 0) // attrs=0
-> debug_dma_map_sg -> add_dma_entry -> EEXIST
This happens because udmabuf builds a per-page scatter-gather list via
sg_set_folio(). When begin_cpu_udmabuf() has already created an sg
table mapped for the misc device, and an importer such as amdgpu maps
the same pages for its own device via map_udmabuf(), the DMA debug
infrastructure sees two active mappings whose physical addresses share
cacheline boundaries and warns about the overlap.
The DMA_ATTR_SKIP_CPU_SYNC flag suppresses this check in
add_dma_entry() because it signals that no CPU cache maintenance is
performed at map/unmap time, making the cacheline overlap harmless.
All other major dma-buf exporters already pass this flag:
- drm_gem_map_dma_buf() passes DMA_ATTR_SKIP_CPU_SYNC
- amdgpu_dma_buf_map() passes DMA_ATTR_SKIP_CPU_SYNC
The CPU sync at map/unmap time is also redundant for udmabuf:
begin_cpu_udmabuf() and end_cpu_udmabuf() already perform explicit
cache synchronization via dma_sync_sgtable_for_cpu/device() when CPU
access is requested through the dma-buf interface.
Pass DMA_ATTR_SKIP_CPU_SYNC to dma_map_sgtable() and
dma_unmap_sgtable() in udmabuf to suppress the spurious warning and
skip the redundant sync. |
| In the Linux kernel, the following vulnerability has been resolved:
iommu/vt-d: Avoid WARNING in sva unbind path
The Intel IOMMU driver allows SVA on devices even if they do not support
PCI/PRI. Commit 39c20c4e83b9 ("iommu/vt-d: Only handle IOPF for SVA when
PRI is supported") modified the SVA bind path to allow this configuration
by skipping IOPF enablement when PRI is missing. However, it failed to
update the unbind path.
This creates an imbalance: the unbind path attempts to disable IOPF for
a device that never had it enabled, triggering a WARNING in
intel_iommu_disable_iopf():
WARNING: drivers/iommu/intel/iommu.c:3475 at intel_iommu_disable_iopf+0x4f/0x90d
Call Trace:
<TASK>
blocking_domain_set_dev_pasid+0x50/0x70
iommu_detach_device_pasid+0x89/0xc0
iommu_sva_unbind_device+0x73/0x150
xe_vm_close_and_put+0x4d2/0x1200 [xe]
Fix this by bypassing IOPF operations for SVA domains on non-PRI hardware
in both the bind and unbind paths. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: us144mkii: capture_urb_complete: redundant usb_anchor_urb corrupts anchor list on each resubmission
In capture_urb_complete(), usb_anchor_urb() is called on every
completion callback, but the URB is already anchored from the
initial submission in tascam_trigger_start(). Each redundant call
corrupts the anchor's doubly-linked list and inflates the URB
refcount. When usb_kill_anchored_urbs() traverses the list during
stream stop / suspend / disconnect, the corrupted list leads to
use-after-free.
Remove the redundant usb_anchor_urb() from the resubmit path. |
| In the Linux kernel, the following vulnerability has been resolved:
fuse-uring: fix data races on ring->ready
On weakly-ordered architectures, the store to fiq->ops can be
reordered past the store to ring->ready, allowing a CPU that sees
ring->ready == true via fuse_uring_ready() to dispatch requests
through a stale fiq->ops pointer. Upgrade the store to
smp_store_release() and the load in fuse_uring_ready() to
smp_load_acquire() so that the preceding WRITE_ONCE(fiq->ops, ...)
is visible to any CPU that observes ring->ready == true.
Additionally, fuse_uring_do_register() publishes ring->ready with
WRITE_ONCE() but the fast-path check reads it with a plain load.
This is a marked-vs-unmarked access that KCSAN will flag. Wrap it in
READ_ONCE() to mark it without adding unnecessary ordering.
Also wrap the fc->ring load in fuse_uring_ready() in READ_ONCE() to
prevent the compiler from reloading it between the NULL check and the
dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
smb/client: Fix error code in smb2_aead_req_alloc()
The "*num_sgs" variable is a u32 so "ERR_PTR(*num_sgs)" doesn't work.
We would have to do something similar to the previous line where it's
cast to int and then long. However, it's simpler to store the return in
an int ret variable.
This bug would eventually result in a crash when dereference the invalid
error pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
iio: adc: spear: Initialize completion before requesting IRQ
In the report from Jaeyoung Chung:
"spear_adc_probe() in drivers/iio/adc/spear_adc.c registers its
interrupt handler with devm_request_irq() before it initializes
st->completion with init_completion(). If an interrupt arrives after
devm_request_irq() and before init_completion(), the handler calls
complete() on an uninitialized completion, causing a kernel panic.
The probe path, in spear_adc_probe():
iodev = devm_iio_device_alloc(&pdev->dev, sizeof(*st)); /* st kzalloc-zeroed */
...
retval = devm_request_irq(&pdev->dev, irq, spear_adc_isr, 0,
LPC32XXAD_NAME, st); /* register handler */
...
init_completion(&st->completion); /* initialize completion */
spear_adc_isr() calls complete():
complete(&st->completion);
If the device raises an interrupt before init_completion() runs,
complete() acquires the uninitialized wait.lock and walks the zeroed
task_list in swake_up_locked(). The zeroed task_list makes list_empty()
return false, so swake_up_locked() dereferences a NULL list entry,
triggering a KASAN wild-memory-access."
Fix the chance of a spurious IRQ causing an uninitialized pointer
dereference by moving init_completion() above devm_request_irq(). |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Grab vmcs12 on CR8 interception update iff vCPU is in guest mode
When updating CR8 intercepts, get vmcs12 if and only if the vCPU is in
guest mode so that a future change can have update CR8 intercepts during
vCPU creation, without running afoul of get_vmcs12()'s lockdep assertion.
------------[ cut here ]------------
debug_locks && !(lock_is_held(&(&vcpu->mutex)->dep_map) || !refcount_read(&vcpu->kvm->users_count))
WARNING: arch/x86/kvm/vmx/nested.h:61 at get_vmcs12 arch/x86/kvm/vmx/nested.h:60 [inline], CPU#0: syz.2.19/5879
WARNING: arch/x86/kvm/vmx/nested.h:61 at vmx_update_cr8_intercept+0x3de/0x4e0 arch/x86/kvm/vmx/vmx.c:6879, CPU#0: syz.2.19/5879
Modules linked in:
CPU: 0 UID: 0 PID: 5879 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:get_vmcs12 arch/x86/kvm/vmx/nested.h:60 [inline]
RIP: 0010:vmx_update_cr8_intercept+0x3de/0x4e0 arch/x86/kvm/vmx/vmx.c:6879
Call Trace:
<TASK>
apic_update_ppr arch/x86/kvm/lapic.c:984 [inline]
kvm_lapic_reset+0x1c24/0x2980 arch/x86/kvm/lapic.c:3023
kvm_vcpu_reset+0x44c/0x1bf0 arch/x86/kvm/x86.c:12986
kvm_arch_vcpu_create+0x746/0x8b0 arch/x86/kvm/x86.c:12847
kvm_vm_ioctl_create_vcpu+0x428/0x930 virt/kvm/kvm_main.c:4201
kvm_vm_ioctl+0x893/0xd50 virt/kvm/kvm_main.c:5159
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
No functional change intended. |
| In the Linux kernel, the following vulnerability has been resolved:
can: esd_usb: kill anchored URBs before freeing netdevs
esd_usb_disconnect() frees each CAN netdev with free_candev() inside
its per-netdev loop and only calls unlink_all_urbs(dev) afterwards.
The per-netdev private data (struct esd_usb_net_priv) is embedded in
the net_device allocation returned by alloc_candev(), so once
free_candev() has run, dev->nets[i] points to freed memory.
unlink_all_urbs() then dereferences the freed dev->nets[i] to kill the
per-netdev TX anchor (usb_kill_anchored_urbs(&priv->tx_submitted)),
clear active_tx_jobs, and reset priv->tx_contexts[].
Reorder the teardown so the anchored URBs are killed before the netdevs
are freed, matching other CAN/USB drivers in the same directory such as
ems_usb, usb_8dev and mcba_usb, which unregister, then unlink, then
free: unregister the netdevs first (which stops their TX queues), call
unlink_all_urbs(dev) once, then free the netdevs.
This issue was found by an in-house static analysis tool. |
| In the Linux kernel, the following vulnerability has been resolved:
riscv: mm: Unconditionally sfence.vma for spurious fault
Svvptc does not guarantee that it's safe to just return here. Since we
have already cleared our bit, if, theoretically, the bounded timeframe
for the accessed page to become valid still hasn't happened after sret,
we could fault again and actually crash.
Hopefully, these spurious faults should be rare enough that this is an
acceptable slowdown. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: do not trim a device which is not writeable
[BUG]
There is a bug report that btrfs/242 can randomly fail with the
following NULL pointer dereference:
run fstests btrfs/242 at 2026-06-01 10:25:08
BTRFS: device fsid d4d7f234-487c-4787-88e4-47a8b68c9874 devid 1 transid 9 /dev/sdc (8:32) scanned by mount (122609)
BTRFS info (device sdc): first mount of filesystem d4d7f234-487c-4787-88e4-47a8b68c9874
BTRFS info (device sdc): using crc32c checksum algorithm
BTRFS warning (device sdc): devid 2 uuid fbe72d72-3272-482d-80fb-ab88ed398192 is missing
BTRFS warning (device sdc): devid 2 uuid fbe72d72-3272-482d-80fb-ab88ed398192 is missing
BTRFS info (device sdc): allowing degraded mounts
BTRFS info (device sdc): turning on async discard
BTRFS info (device sdc): enabling free space tree
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018
user pgtable: 4k pages, 48-bit VAs, pgdp=000000013fd6b000
CPU: 4 UID: 0 PID: 122625 Comm: fstrim Not tainted 7.0.10-2-default #1 PREEMPT(full) openSUSE Tumbleweed e9a5f6b24978fba3bf015a992f865837fdfff3dd
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20250812-19.fc42 08/12/2025
pstate: 01400005 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : btrfs_trim_fs+0x34c/0xa00 [btrfs]
lr : btrfs_trim_fs+0x1f0/0xa00 [btrfs]
Call trace:
btrfs_trim_fs+0x34c/0xa00 [btrfs f02c1d570ceea621c69d302ba75dd61868083840] (P)
btrfs_ioctl_fitrim+0xe8/0x178 [btrfs f02c1d570ceea621c69d302ba75dd61868083840]
btrfs_ioctl+0xdd4/0x2bd8 [btrfs f02c1d570ceea621c69d302ba75dd61868083840]
__arm64_sys_ioctl+0xac/0x108
invoke_syscall.constprop.0+0x5c/0xd0
el0_svc_common.constprop.0+0x40/0xf0
do_el0_svc+0x24/0x40
el0_svc+0x40/0x1d0
el0t_64_sync_handler+0xa0/0xe8
el0t_64_sync+0x1b0/0x1b8
Code: 17ffff83 f94017e0 f9002be0 f9402ea0 (f9400c00)
---[ end trace 0000000000000000 ]---
Also the reporter is very kind to test the following ASSERT() added to
btrfs_trim_free_extents_throttle():
ASSERT(device->bdev,
"devid=%llu path=%s dev_state=0x%lx\n",
device->devid, btrfs_dev_name(device), device->dev_state);
And it shows the following output:
assertion failed: device->bdev, in extent-tree.c:6630 (devid=2 path=/dev/sdd dev_state=0x82)
Which means the device->bdev is NULL, and the dev_state is
BTRFS_DEV_STATE_IN_FS_METADATA | BTRFS_DEV_STATE_ITEM_FOUND, without
BTRFS_DEV_STATE_WRITEABLE flag set.
[CAUSE]
The pc points to the following call chain:
btrfs_trim_fs()
|- btrfs_trim_free_extents()
|- btrfs_trim_free_extents_throttle()
|- bdev_max_discard_sectors(device->bdev)
So the NULL pointer dereference is caused by device->bdev being NULL.
This looks impossible by a quick glance, as just before calling
btrfs_trim_free_extents_throttle(), we have skipped any device that has
BTRFS_DEV_STATE_MISSING flag set.
However in this particular case, there is a window where the missing
device is later re-scanned, causing btrfs to remove the
BTRFS_DEV_STATE_MISSING flag:
btrfs_control_ioctl()
|- btrfs_scan_one_device()
|- device_list_add()
|- rcu_assign_pointer(device->name, name);
| This updates the missing device's path to the new good path.
|
|- clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state)
This removes the BTRFS_DEV_STATE_MISSING flag.
This allows the missing device to re-appear and clear the
BTRFS_DEV_STATE_MISSING flag. However the device still does not have
the BTRFS_DEV_STATE_WRITEABLE flag set, nor is its bdev pointer updated.
The bdev pointer remains NULL, triggering the crash later.
[FIX]
This is a big de-synchronization between BTRFS_DEV_STATE_MISSING and
device->bdev pointer, and shows a gap in btrfs's re-appearing-device
handling.
The proper handling of re-appearing device will need quite some extra
work, which is out of the context of this small
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_fs: initialize reset_work at allocation time
ffs_fs_kill_sb() unconditionally calls cancel_work_sync() on
ffs->reset_work when a functionfs instance is unmounted:
ffs_data_reset(ffs);
cancel_work_sync(&ffs->reset_work);
However ffs->reset_work is only ever initialized via INIT_WORK() in
ffs_func_set_alt() and ffs_func_disable(), and only on the
FFS_DEACTIVATED path. That state is reached solely by ffs_data_closed()
when the instance is mounted with the "no_disconnect" option, so for the
common case (no "no_disconnect", or mounted and unmounted without ever
being deactivated) reset_work is never initialized.
ffs_data_new() allocates the ffs_data with kzalloc_obj() and does not
initialize reset_work, and ffs_data_reset()/ffs_data_clear() do not touch
it either, so reset_work.func is left NULL. cancel_work_sync() on such a
work then trips the WARN_ON(!work->func) guard in __flush_work():
WARNING: kernel/workqueue.c:4301 at __flush_work+0x330/0x360, CPU#3: umount
Call trace:
__flush_work
cancel_work_sync
ffs_fs_kill_sb [usb_f_fs]
deactivate_locked_super
deactivate_super
cleanup_mnt
__cleanup_mnt
task_work_run
exit_to_user_mode_loop
el0_svc
On older kernels cancel_work_sync() on a zero-initialized work struct was
a silent no-op, which hid the missing initialization.
Initialize reset_work once in ffs_data_new() so it is always valid for
the lifetime of the ffs_data, and drop the now-redundant INIT_WORK()
calls from the two deactivation paths. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix double-free in SMB2_close() replay
A response-bearing attempt can return a replayable error and free its
response buffer. If SMB2_close_init() fails before the next send, cleanup
retains the previous buffer type and frees that response again.
Reset response bookkeeping before each attempt to prevent the stale free. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: amlogic - avoid double cleanup in meson_crypto_probe()
When meson_allocate_chanlist() fails after a partial allocation, it already
unwinds the allocated chanlist state through its local error path.
meson_crypto_probe() then jump to error_flow and calls
meson_free_chanlist() again, causing the same per-flow resources to be torn
down twice. In the reproduced failure path, the second teardown
re-entered crypto_engine_exit() on an already destroyed worker and KASAN
reported a slab-use-after-free in kthread_destroy_worker().
Prevent double-free by handling partial allocation failures locally within
meson_allocate_chanlist() and skipping the outer cleanup path.
The bug was first flagged by an experimental analysis tool we are
developing for kernel memory-management bugs while analyzing
v6.13-rc1. The tool is still under development and is not yet publicly
available.
The bug was reproduced in a QEMU x86_64 guest booted with KASAN on v7.1,
using the reproducer under tools/testing/meson_crypto_probe. The reproducer
forces the second dma_alloc_attrs() call in the gxl-crypto probe path to
return NULL, making meson_allocate_chanlist() fail after partial
initialization. On the unpatched kernel this reliably triggered a
slab-use-after-free. With this fix applied, the same reproducer no longer
emits any KASAN report and the probe fails cleanly with -ENOMEM.
==================================================================
BUG: KASAN: slab-use-after-free in kthread_destroy_worker+0xb2/0xd0
Read of size 8 at addr ff1100010c057a68 by task insmod/265
CPU: 1 UID: 0 PID: 265 Comm: insmod Tainted: G O 7.1.0-rc2-00376-g810af9adc907-dirty #10 PREEMPT(lazy)
Tainted: [O]=OOT_MODULE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x68/0xa0
print_report+0xcb/0x5e0
? __virt_addr_valid+0x21d/0x3f0
? kthread_destroy_worker+0xb2/0xd0
? kthread_destroy_worker+0xb2/0xd0
kasan_report+0xca/0x100
? kthread_destroy_worker+0xb2/0xd0
kthread_destroy_worker+0xb2/0xd0
meson_crypto_probe+0x4d0/0xc10 [amlogic_gxl_crypto]
platform_probe+0x99/0x140
really_probe+0x1c6/0x6a0
? __pfx___device_attach_driver+0x10/0x10
__driver_probe_device+0x248/0x310
? acpi_driver_match_device+0xb0/0x100
driver_probe_device+0x48/0x210
? __pfx___device_attach_driver+0x10/0x10
__device_attach_driver+0x160/0x320
bus_for_each_drv+0x104/0x190
? __pfx_bus_for_each_drv+0x10/0x10
? _raw_spin_unlock_irqrestore+0x2c/0x50
__device_attach+0x19d/0x3b0
? __pfx___device_attach+0x10/0x10
? do_raw_spin_unlock+0x53/0x220
device_initial_probe+0x78/0xa0
bus_probe_device+0x5b/0x130
device_add+0xcfd/0x1430
? __pfx_device_add+0x10/0x10
? insert_resource+0x34/0x50
? lock_release+0xc9/0x290
platform_device_add+0x24e/0x590
? __pfx_meson_crypto_probe_repro_init+0x10/0x10 [meson_crypto_probe_repro]
meson_crypto_probe_repro_init+0x330/0xff0 [meson_crypto_probe_repro]
do_one_initcall+0xc0/0x450
? __pfx_do_one_initcall+0x10/0x10
? _raw_spin_unlock_irqrestore+0x2c/0x50
? __create_object+0x59/0x80
? kasan_unpoison+0x27/0x60
do_init_module+0x27b/0x7d0
? __pfx_do_init_module+0x10/0x10
? kasan_quarantine_put+0x84/0x1d0
? kfree+0x32c/0x510
? load_module+0x561e/0x5ff0
load_module+0x54fe/0x5ff0
? __pfx_load_module+0x10/0x10
? security_file_permission+0x20/0x40
? kernel_read_file+0x23d/0x6e0
? mmap_region+0x235/0x4a0
? __pfx_kernel_read_file+0x10/0x10
? __file_has_perm+0x2c0/0x3e0
init_module_from_file+0x158/0x180
? __pfx_init_module_from_file+0x10/0x10
? __lock_acquire+0x45a/0x1ba0
? idempotent_init_module+0x315/0x610
? lock_release+0xc9/0x290
? lock
---truncated--- |
