| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
drop_monitor: use timer_shutdown_sync() to prevent timer rearming during teardown
In drop_monitor teardown paths (net_dm_trace_off_set(),
net_dm_hw_monitor_stop(), and error unwind paths in net_dm_trace_on_set()
and net_dm_hw_monitor_start()), per-CPU timers are stopped using
timer_delete_sync() followed by cancel_work_sync().
However, there is a circular dependency between send_timer and
dm_alert_work:
1) sched_send_work() (timer callback) schedules dm_alert_work.
2) send_dm_alert() / net_dm_hw_summary_work() calls reset_per_cpu_data()
or net_dm_hw_reset_per_cpu_data().
3) If memory allocation fails under memory pressure in the reset
function, it re-arms the timer via mod_timer(&data->send_timer, ...).
If dm_alert_work is running concurrently while timer_delete_sync()
executes on another CPU, an allocation failure in the worker will
re-arm the timer after timer_delete_sync() has already returned.
Once cancel_work_sync() completes and module_put() is called, the timer
remains active in the timer wheel. If the module is then unloaded, the
timer will fire and execute sched_send_work() in freed memory,
triggering a kernel panic / use-after-free.
Switch from timer_delete_sync() to timer_shutdown_sync(). This guarantees
that any in-flight timer handler has finished and prevents subsequent
re-arming attempts from running workers from succeeding. When monitoring
is restarted later, timer_setup() is invoked, which cleanly
re-initializes the timer. |
| In the Linux kernel, the following vulnerability has been resolved:
net: bridge: vlan: fix bugs caused by switchdev deletion errors
Allowing switchdev to prevent vlan deletion and error out in __vlan_del
could cause multiple different issues - inconsistent state, memory leaks
when flushing, NULL pointer dereference on bridge error when flushing.
It doesn't make sense to allow it to stop __vlan_del, so log the error
and continue with software vlan deletion. This is also consistent with
8021q behaviour. |
| In the Linux kernel, the following vulnerability has been resolved:
netlink: do not free nlk->groups while lockless readers can use it
netlink_realloc_groups() uses krealloc() under netlink_table_grab().
Whenever NLGRPSZ(groups) lands in a different kmalloc bucket, the old
bitmap is freed immediately.
Two readers of nlk->groups / nlk->ngroups do not hold the netlink
table lock:
1) sk_diag_dump_groups(). Hashed (bound) sockets are dumped from the
rhashtable walk in __netlink_diag_dump(), which only holds RCU.
Only the mc_list part of the dump takes nl_table_lock.
2) netlink_native_seq_show() (/proc/net/netlink), whose walk has been
lockless since commit 21e4902aea80 ("netlink: Lockless lookup with
RCU grace period in socket release").
Both can read a freed buffer, and sk_diag_dump_groups() can also read
past the end of the old (smaller) buffer if it happens to load the old
@groups pointer together with the new @ngroups value, copying the
result into a NETLINK_DIAG_GROUPS attribute.
This is the same class of bug that commit f773608026ee ("netlink:
access nlk groups safely in netlink bind and getname") fixed for bind()
and getname(); these two readers were missed. Simply grabbing the table
lock in sk_diag_dump_groups() is not an option, because it is also
called with nl_table_lock already held from the mc_list section of the
dump.
Make the lockless readers safe instead:
- Allocate a new bitmap and free the old one after an RCU grace period,
instead of relying on the implicit kfree() done by krealloc().
- Publish @groups before @ngroups, both with release semantics, and have
the lockless readers load @ngroups first. A reader can then never pair
the new (bigger) size with the old (smaller) buffer, and a reader
picking up the new pointer while still seeing the old size is
guaranteed to see the initialized bitmap.
netlink_realloc_groups() is called from process context (bind() and
setsockopt()), so kfree_rcu_mightsleep() can be used, once the table
has been released. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: PPC: Book3S HV: fix use-after-free in kvmhv_emulate_tlbie_all_lpid()
kvmhv_emulate_tlbie_all_lpid() iterates the nested-guest IDR and drops
mmu_lock before calling kvmhv_emulate_tlbie_lpid(), but does not hold a
reference on the kvm_nested_guest pointer obtained from the IDR. A
concurrent vCPU issuing a single-LPID tlbie (is=2, ric=2) can race
through kvmhv_flush_nested() -> kvmhv_remove_nested() -> idr_remove /
--refcnt -> kvmhv_release_nested() -> kfree(gp) in that window, leaving
the iterating vCPU with a dangling pointer. The subsequent
mutex_lock(&gp->tlb_lock) and accesses to gp->shadow_pgtable,
gp->shadow_lpid and gp->l1_host all touch freed memory. The free path
is fully L1-controlled.
Fix this by incrementing gp->refcnt inside the loop before dropping
mmu_lock, mirroring what kvmhv_get_nested() does, and releasing the
reference with kvmhv_put_nested() after the per-guest work completes.
This is the same get/put discipline already used at every other
call site that drops mmu_lock while holding a nested-guest pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/iommu: Fix the overflow validation in iommu_tce_check_ioba
The commit b1af23d836f8 ("KVM: PPC: iommu: Unify TCE checking") unified
IOBA parameter checking across KVM and VFIO into iommu_tce_check_ioba().
While doing so, the passed in argument npages is ignored and constant
value '1' is used leaving out a possible overflow as the callers can
legitimately be using npages > 1 for H_STUFF_TCE or H_PUT_TCE_INDIRECT
cases.
Fix this by accounting for 'npages', checking for arithmetic overflow,
and verifying that the entire requested range (ioba - offset + npages)
does not exceed the table capacity 'size'. |
| In the Linux kernel, the following vulnerability has been resolved:
futex: Also allocate private hash on vfork()
As Jann demonstrated, it is entirely feasible to access the mm through vfork().
Therefore we need to allocate a private hash on vfork() as well as any other
CLONE_VM user.
Specifically, it must be avoided to have (private) futex waiters before
allocating the private hash. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/xe/i2c: Disable IRQ on unbind
Currently, struct xe_i2c is freed before SGUnit IRQ is disabled in unbind
path, leaving a potential UAF in case I2C IRQ is hit during this small
window. Explicitly disable I2C IRQ in xe_i2c_remove() and fix this.
(cherry picked from commit 8ba5c8b8ab3fd362267c11df2cd5a90ee46f6e24) |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: handle lack of space when cleaning up verity items
When enable_verity() hits the qgroup limit, rollback_verity() needs its
own metadata reservation. When the qgroup limit or lack of space refuses
the rollback, the whole filesystem is forced read-only even though the
qgroup limit was for one subvolume only. Also orphan cleanup at the next
mount fails the same way, so the leftover items are never removed: with
-EDQUOT the subvolume stays unreachable, and with -ENOSPC on a full
filesystem the next read-write mount fails.
Start transactions with btrfs_start_transaction_fallback_global_rsv() in
btrfs_orphan_cleanup(), drop_verity_items() and rollback_verity(). Those
calls only delete items and free the space in the end, so they may use
the global reserve and skip the qgroup limit, which avoids -ENOSPC and
-EDQUOT. |
| In the Linux kernel, the following vulnerability has been resolved:
net: remove WARN_ON_ONCE() from the dev_fill_forward_path() loop check
ipip_fill_forward_path() and ip6_tnl_fill_forward_path() look up the
route to the tunnel's remote endpoint and set ctx->dev to its device,
which is the tunnel itself when that route resolves back to the tunnel.
dev_fill_forward_path() then makes no progress and trips
WARN_ON_ONCE(last_dev == ctx->dev) as soon as a flowtable tries to
offload a flow through the tunnel. That routing loop is a configuration
any CAP_NET_ADMIN user can set up, and ip_tunnel_xmit() and
ip6_tnl_xmit() already treat it as a tx error, so remove the warning and
just fail the walk, as commit 008e7a7c293b ("net: remove WARN_ON_ONCE
when accessing forward path array") did for the path stack overflow. |
| In the Linux kernel, the following vulnerability has been resolved:
eth: fbnic: ring the doorbell if a burst ends in a drop
fbnic_tx_map() skips the doorbell write, and the completion request,
for every packet handed to it with xmit_more set, counting on the
packet which ends the burst to publish them all. When that packet is
dropped instead - skb_put_padto(), skb_cow_head() or a DMA mapping
failure - nothing rings. The descriptors of the preceding packets stay
invisible to the HW until the next transmit on that queue, which for a
burst-then-idle workload may never come.
Remember the meta descriptor of the last packet left without a doorbell
and flush it from the error paths. The completion request has to be set
on that descriptor rather than simply writing the tail, otherwise the HW
would transmit the packets but never report a head, and the ring would
fill up and stall for good.
This is very similar to Joe's recent series of fixes for bnxt.
Not seen in real life, reproduced under QEMU with failure injection. |
| In the Linux kernel, the following vulnerability has been resolved:
net: lock the socket in sock_gettstamp()
sk->sk_flags must only be changed while holding the socket lock,
because sock_set_flag() and sock_reset_flag() use non atomic
operations (__set_bit() and __clear_bit()).
sock_gettstamp() is one of the last places where a bit of sk->sk_flags
is changed from a syscall without owning the socket lock, through
sock_enable_timestamp(sk, SOCK_TIMESTAMP).
sk_set_memalloc() and sk_clear_memalloc() also change sk->sk_flags
without the socket lock, but their callers (nbd, iscsi_tcp, nvme-tcp,
sunrpc, wireguard) need a careful audit, this will be addressed in a
separate patch.
Jungwoo Lee and Wongi Lee reported an UDP socket use-after-free
caused by this bug: a SIOCGSTAMPNS_NEW ioctl racing with bind()
can cancel the SOCK_RCU_FREE bit that udp_lib_get_port() just set,
because both threads perform a read-modify-write on the same word.
CPU 0 (bind) CPU 1 (SIOCGSTAMPNS_NEW)
-------------------------------- ----------------------------
read sk_flags = F read sk_flags = F
compute F | BIT(SOCK_RCU_FREE) compute F | BIT(SOCK_TIMESTAMP)
store F | BIT(SOCK_RCU_FREE)
sk_add_node_rcu(sk, ...)
store F | BIT(SOCK_TIMESTAMP)
After the lost update, SOCK_RCU_FREE is clear while the socket is
visible to lockless UDP receive lookups. sk_destruct() then frees
the socket immediately instead of waiting for a RCU grace period,
while the receive path still holds a reference-less pointer to it:
BUG: KASAN: slab-use-after-free in ipv4_pktinfo_prepare+0x30/0x410
Read of size 8 at addr ffff888008806610 by task exploit/207
CPU: 0 UID: 1000 PID: 207 Comm: exploit Not tainted 6.12.95+ #1
ipv4_pktinfo_prepare+0x30/0x410
udp_queue_rcv_one_skb+0x51c/0x1180
udp_unicast_rcv_skb+0x109/0x350
ip_protocol_deliver_rcu+0x14b/0x310
ip_local_deliver_finish+0x29d/0x390
ip_local_deliver+0x24d/0x2a0
Only grab the socket lock when SOCK_TIMESTAMP has to be set,
to keep the common case lockless. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ethernet: cortina: Ack RX overrun interrupt correctly
The RX overrun interrupt is reported in interrupt status register 4, but
gmac_irq() acknowledges it using the RX descriptor error bit from status
register 0. For GMAC0 this writes the GMAC1 overrun bit, while for GMAC1
the shift leaves no bit in the 32-bit register.
Acknowledge the same per-port RX overrun bit that was detected. |
| In the Linux kernel, the following vulnerability has been resolved:
net: psp: avoid conflicts with skb->decrypted and sk_validate_xmit_skb()
PSP conflicts with TLS ULP in its usage of both skb->decrypted and
sk->sk_validate_xmit_skb().
Make PSP mutually exclusive with TLS ULP, the only other user of either
of these. As other users of skb->decrypted come along, they can be added
to sk_has_decrypt_user(). It would make sense to also assert that
sk->sk_validate_xmit_skb() is also NULL in both of these setup paths for
similar future proofing, but the PSP listener/sk_clone() path is still
broken and it could be seen as a regression to not allow rx assoc to run
on a child of a listener socket with PSP tx assoc state.
Include all TCP ULPs in the sk_has_decrypt_user() check, even though TLS
is the only one that conflicts with PSP via the decrypted bit. This is
intentional because PSP was not designed to be used with ULPs. It is
best to close off surface area that may make bugs reachable, until
someone wishes to design and test an actual user of PSP with ULPs. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/kprobes: Fix crash when probing CS CALL instructions
When using eBPF to probe CS CALL instructions within a function,
a crash can be triggered.
The eBPF tool probes offset 257 of the __hrtimer_run_queues()
function:
<__hrtimer_run_queues+249>: nopl 0x0(%rax,%rax,1)
<__hrtimer_run_queues+254>: mov %r14,%rdi
<__hrtimer_run_queues+257>: cs call <__x86_indirect_thunk_r12>
<__hrtimer_run_queues+263>: mov %eax,%r12d
<__hrtimer_run_queues+266>: xchg %ax,%ax
<__hrtimer_run_queues+268>: mov %r13,%rdi
Which triggers this crash:
BUG: unable to handle page fault for address: 00000000000f41c9
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] SMP NOPTI
CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P
RIP: 0010:__hrtimer_run_queues+0x106/0x230
Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is
at the 6th byte of the above CS CALL instruction. Since the CS CALL
instruction occupies 6 bytes, the exception occurred in the middle of that
call instruction.
The root cause is that when using eBPF tools to probe in the middle of a
function, a kprobe with INT3 is used as the underlying implementation.
During single-step emulation of the original CALL instruction,
int3_emulate_call() assumes that the probed CALL instruction is 5 bytes
long. However, the actual CS-prefixed CALL instruction occupies 6 bytes,
so it constructs an incorrect exception return address. When the CPU
returns from the kprobe handler, the next instruction to be executed is at
the address of the last byte of that CS CALL instruction. Coincidentally,
starting from that address, the CPU fetches and decodes a completely
different instruction, which ultimately triggers a kernel crash.
Fix the issue by using the actual instruction length obtained from
the instruction decoder when constructing the exception return
address, rather than relying on the hardcoded CALL_INSN_SIZE macro.
[ mingo: Refined the changelog ] |
| In the Linux kernel, the following vulnerability has been resolved:
net: mvpp2: prevent buffer overflow in page_pool allocation
The per‑processor buffering scheme is supported only if the
number of pools (nrxqs * 2) does not exceed MVPP2_BM_MAX_POOLS (8).
This is already checked in mvpp2_probe() during the initial
activation of percpu_pools.
However, mvpp2_change_mtu() may later call
mvpp2_bm_switch_buffers(priv, true) without this check, which can
lead to an out-of-bounds access in the priv->page_pool array in
mvpp2_bm_init(). The array is sized to hold MVPP2_PORT_MAX_RXQ
entries, and mvpp2_get_nrxqs() may return exactly that value. The
per-CPU scheme then doubles it to nrxqs * 2, exceeding the array
bounds.
Check that the hardware version is MVPP22 or newer and that the
number of pools (nrxqs * 2) does not exceed MVPP2_BM_MAX_POOLS
before switching to per-CPU mode.
Found by Linux Verification Center (linuxtesting.org) with SVACE. |
| In the Linux kernel, the following vulnerability has been resolved:
net: skbuff: do not leave stale header offsets after pskb_carve()
pskb_carve_inside_header() and pskb_carve_inside_nonlinear() remove
the first bytes of a packet and reallocate skb->head.
All the headers that were present before the operation are gone,
but both functions call skb_headers_offset_update(skb, 0), which
is a no-op : skb->mac_header, skb->network_header,
skb->transport_header and skb->csum_start keep their old values and
now describe bytes which are no longer there.
Both helpers size the new head from the old skb_end_offset(), so the
stale offsets still land inside the new allocation. They point past
skb_tail_pointer() though, to bytes that were never initialized.
pskb_carve_inside_nonlinear() is the worst case, because it leaves a
zombie skb with an empty linear part (skb->data ==
skb_tail_pointer(skb), skb_headlen(skb) == 0), while
skb_mac_header_was_set() is still true and skb->mac_header is way
ahead of skb->data.
The only user of pskb_extract() is rds_tcp_data_recv(), and the
carved skb is queued on tinc->ti_skb_list. When the RDS incoming
message is released, rds_tcp_inc_free() calls skb_queue_purge(),
which frees the skbs with SKB_DROP_REASON_QUEUE_PURGE. This is
visible from drop_monitor, which then tries to pull back to the
(bogus) mac header :
skbuff: __skb_pull(len=234)
skb len=6968 data_len=6968 headroom=0 headlen=0 tailroom=0
end-tail=384 mac=(234,14) mac_len=14 net=(248,40) trans=288
shinfo(txflags=0 nr_frags=1 gso(size=1428 type=16 segs=5))
csum(0x100120 start=288 offset=16 ip_summed=3 complete_sw=0 valid=1 level=0)
hash(0x7b446c6c sw=0 l4=1) proto=0x86dd pkttype=0 iif=60
kernel BUG at ./include/linux/skbuff.h:2847!
Add skb_carve_reset_headers() to mark the mac and transport headers
as not set, reset the network header, clear skb->mac_len, and drop
a now meaningless CHECKSUM_PARTIAL (csum_start no longer describes
anything).
Invalidate the inner offsets as well. Unlike mac_header and
transport_header they have no "unset" sentinel, so a leftover
non-zero value still looks like a real header. Zero
skb->inner_mac_header, skb->inner_network_header,
skb->inner_transport_header, skb->inner_protocol and
skb->encapsulation, so that all the header state is invalidated in
one place.
v2: fixed an inaccurate changelog. The stale offsets stay inside the
new skb->head, which is never smaller than the old one, they
simply point past skb_tail_pointer() to bytes that are gone.
Thanks to Xuanqiang Luo for insisting on this.
Also invalidate the inner header state, as suggested by the
netdev AI review :
https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260911114922.621937-1-edumazet%40google.com |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: check ras and obj before dereference
nbio_v7_9_handle_ras_controller_intr_no_bifring() dereferences ras and obj
without checking either for NULL. Both amdgpu_ras_get_context() and
amdgpu_ras_find_obj() can return NULL, e.g. during the window between
adev->nbio.ras being set (early in amdgpu_ras_init(), by design, to
enable the fatal-error interrupt as soon as possible) and the PCIE_BIF
ras object actually being created in RAS late_init. Any interrupt in that
window crashes in hard-IRQ context.
This is analogous to commit d190b459b2a4 ("drm/amdgpu: the warning
dereferencing obj for nbio_v7_4"), which fixed the same issue in the
nbio_v7_4 handler.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
(cherry picked from commit c7071767a50a32ed727cf800ac84372429e3b4b3) |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: abort transaction on failure to update inode for hole punching and reflinking
If we fail to update the inode we error out without aborting the
transaction, which can result in a persistent inconsistency if after
the failure the transaction is committed, as we have dropped file
extent items from a range and either punched a hole or insert a new file
extent item for that range (for reflinks).
So add the missing transaction abort. |
| In the Linux kernel, the following vulnerability has been resolved:
perf: Fix null pointer access in is_include_guest_event()
A typical module unload occurring event when there is an active perf
connection leads to freeing of the pmu pointer. The call log is something
like:
..
__pmu_detach_event
pmu_detach_event
pmu_detach_events
perf_pmu_unregister
..
__pmu_detach_event() sets event->pmu to null. When the perf connection
finally is closed, the following stack trace is observed:
Oops: general protection fault, kernel NULL pointer dereference
...
RIP: 0010:_free_event+0x3e/0x370
...
Call Trace:
...
perf_event_release_kernel+0x260/0x2d0
perf_release+0x12/0x20
A call to mediated_pmu_unaccount_event() inside _free_event() is the root
cause of this crash. Adding a check inside is_include_guest_event() ensures
we don't accidentally access a null pmu ptr. In addition to this, we will
now call mediated_pmu_unaccount_event() before clearing the pmu ptr so that
nr_include_guest_events counts are maintained correctly. |
| In the Linux kernel, the following vulnerability has been resolved:
9p: Fix v9fs_issue_write() to update i_size and remote_i_size
Fix v9fs_issue_write() to update i_size and remote_i_size to the new size
of the server file if we made it larger, using the start fpos and the count
returned by p9_client_write() to calculate the new minimum file size.
This assumes that if the 9P server makes a short write (say it hits
ENOSPC), a reduced count is returned. |
