| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: hold sk properly in iso_conn_ready
sk deref in iso_conn_ready must be done either under conn->lock, or
holding a refcount, to avoid concurrent close. conn->sk is currently
accessed without either:
[Task 1] [Task 2]
iso_sock_release
iso_conn_ready
sk = conn->sk
lock_sock(sk)
conn->sk = NULL
lock_sock(sk)
release_sock(sk)
iso_sock_kill(sk)
UAF on sk deref
Fix possible UAF by holding sk refcount in iso_conn_ready(). Also
recheck after lock_sock that the socket is still valid. Adjust locking
so conn->sk is cleared only under lock_sock. |
| In the Linux kernel, the following vulnerability has been resolved:
dlm: fix add msg handle in send_queue ordered
In a benchmark scenario triggering a lot of requests that triggers a lot
of DLM messages on the network it can be that the mh->seq is not ordered
according the oldest seq number. This ordering is required by
dlm_receive_ack as "before(mh->seq, seq)" will stop to check for older
sequence numbers that are ordered in the tail of "node->send_queue".
The side effects of not having it correct ordered regarding
"before(mh->seq, seq)" are refcounting issues and use-after free.
I only was able to reproduce this issue in a experimental DLM branch
and a user space DLM benchmark that uses io_uring. After changing this I
don't experienced any refcounting with the sending buffer issues anymore. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: seq: oss: Fix UAF at handling events with embedded SysEx data
The OSS sequencer processes the input MIDI bytes into a sequencer
event to be dispatched later (in snd_seq_oss_midi_putc() called from
snd_seq_oss_process_event()). When it's a SysEx data, the event
record contains data.ext.ptr pointer to the original SysEx bytes, and
the referred data is copied into the pool afterwards at dispatching.
The problem is that, if the sequencer port gets closed concurrently
before the dispatch, the OSS sequencer core also releases the
resources (in snd_seq_oss_midi_check_exit_port()), while the pending
event may hold a stale pointer, eventually leading to a UAF at a later
dispatch.
Fortunately, there is already a refcounting mechanism (snd_use_lock_t)
for the OSS MIDI device access, and for addressing the issue above, we
just need to extend the refcount until the event gets dispatched.
This patch extends snd_seq_oss_process_event() to give back the
refcount object, which is in turn released after calling the sequencer
dispatcher with the given event in the caller side.
According to the original report, KASAN report as below:
KASAN slab-use-after-free in snd_seq_event_dup+0x40c/0x470
RIP: 0033:0x7f2cb66a6340
Read of size 6
Call trace:
dump_stack_lvl+0x73/0xb0 (?:?)
print_report+0xd1/0x650 (?:?)
srso_alias_return_thunk+0x5/0xfbef5 (?:?)
__virt_addr_valid+0x1a7/0x340 (?:?)
kasan_complete_mode_report_info+0x64/0x200 (?:?)
kasan_report+0xf7/0x130 (?:?)
snd_seq_event_dup+0x40c/0x470 (?:?)
kasan_check_range+0x10c/0x1c0 (?:?)
__asan_memcpy+0x27/0x70 (?:?)
snd_seq_event_dup+0x9/0x470 (?:?)
snd_seq_client_enqueue_event+0x139/0x240 (?:?)
_raw_spin_unlock_irqrestore+0x4b/0x60 (?:?)
snd_seq_kernel_client_enqueue+0x102/0x120 (?:?)
snd_seq_oss_write+0x416/0x4e0 (?:?)
apparmor_file_permission+0x20/0x30 (?:?)
odev_write+0x3b/0x60 (?:?)
vfs_write+0x1ce/0x850 (?:?)
lock_release+0xc8/0x2a0 (?:?)
__kasan_check_write+0x18/0x20 (?:?)
__mutex_unlock_slowpath+0x129/0x510 (?:?)
ksys_write+0xe1/0x180 (?:?)
mutex_unlock+0x16/0x20 (?:?)
odev_ioctl+0x65/0xc0 (?:?)
__x64_sys_write+0x46/0x60 (?:?)
x64_sys_call+0x7d/0x20d0 (?:?)
do_syscall_64+0xc1/0x360 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f (?:?) |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/siw: Fix endpoint/socket association handling
Disassociating a socket from an endpoint via siw_socket_disassoc() may
release the last reference on that endpoint and free it. Therefore, don't
clear the endpoints socket pointer after calling that function, but
within.
This fixes a:
BUG: KASAN: slab-use-after-free in siw_cm_work_handler (drivers/infiniband/sw/siw/siw_cm.c:1053 drivers/infiniband/sw/siw/siw_cm.c:1075)
which occurred after processing a malformed MPA request during connection
establishment, causing the new endpoint to be closed. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: seq: Clear variable event pointer on read
snd_seq_read() copies a queued variable-length event header to userspace
before expanding the payload. Queued variable-length events use
SNDRV_SEQ_EXT_CHAINED internally, and data.ext.ptr points at the first
extension cell.
The read side strips SNDRV_SEQ_EXT_* bits from data.ext.len before the
copy, but it leaves data.ext.ptr untouched. A userspace sequencer client
can therefore write a direct variable event to itself and read back the
extension-cell kernel address from the returned header.
Clear the temporary header pointer before copy_to_user(). The original
queued event remains unchanged and is still passed to
snd_seq_expand_var_event(), so payload expansion keeps using the
internal chain. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_core: Fix UAF in hci_unregister_dev()
hci_unregister_dev() does not disable cmd_timer and ncmd_timer
before the hci_dev structure is freed. If a timeout fires
during device teardown, the callback dereferences freed memory
(including the hdev->reset function pointer), leading to a
use-after-free.
Add disable_delayed_work_sync() calls alongside the existing
disable_work_sync() calls to ensure both timers are fully
quiesced before teardown proceeds. |
| In the Linux kernel, the following vulnerability has been resolved:
net: watchdog: fix refcount tracking races
Blamed commit converted the untracked dev_hold()/dev_put() calls
in the watchdog code to use the tracked dev_hold_track()/dev_put_track()
(which were later renamed/interfaced to netdev_hold() and netdev_put()).
By introducing dev->watchdog_dev_tracker to store the
reference tracking information without adding synchronization
between netdev_watchdog_up() and dev_watchdog(), it enabled the
race condition where this pointer could be overwritten or freed
concurrently, leading to the list corruption crash syzbot reported:
list_del corruption, ffff888114a18c00->next is NULL
kernel BUG at lib/list_debug.c:52 !
Oops: invalid opcode: 0000 [#1] SMP KASAN PTI
CPU: 1 UID: 0 PID: 91 Comm: kworker/u8:5 Not tainted syzkaller #0 PREEMPT(lazy)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound linkwatch_event
RIP: 0010:__list_del_entry_valid_or_report.cold+0x22/0x2a lib/list_debug.c:52
Call Trace:
<TASK>
__list_del_entry_valid include/linux/list.h:132 [inline]
__list_del_entry include/linux/list.h:246 [inline]
list_move_tail include/linux/list.h:341 [inline]
ref_tracker_free+0x1a7/0x6c0 lib/ref_tracker.c:329
netdev_tracker_free include/linux/netdevice.h:4491 [inline]
netdev_put include/linux/netdevice.h:4508 [inline]
netdev_put include/linux/netdevice.h:4504 [inline]
netdev_watchdog_down net/sched/sch_generic.c:600 [inline]
dev_deactivate_many+0x28c/0xfe0 net/sched/sch_generic.c:1363
dev_deactivate+0x109/0x1d0 net/sched/sch_generic.c:1397
linkwatch_do_dev net/core/link_watch.c:184 [inline]
linkwatch_do_dev+0xd3/0x120 net/core/link_watch.c:166
__linkwatch_run_queue+0x3a5/0x810 net/core/link_watch.c:240
linkwatch_event+0x8f/0xc0 net/core/link_watch.c:314
process_one_work+0xa0e/0x1980 kernel/workqueue.c:3314
process_scheduled_works kernel/workqueue.c:3397 [inline]
worker_thread+0x5ef/0xe50 kernel/workqueue.c:3478
kthread+0x370/0x450 kernel/kthread.c:436
ret_from_fork+0x69a/0xc80 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
This patch has three coordinated parts:
1) Add dev->watchdog_lock and dev->watchdog_ref_held to serialize watchdog operations.
2) Remove netdev_watchdog_up() call from netif_carrier_on():
This ensures netdev_watchdog_up() is only called from process/BH context
(via linkwatch workqueue dev_activate()), allowing us to use
spin_lock_bh() for synchronization.
3) Synchronize watchdog up and watchdog timer:
Protect netdev_watchdog_up() with tx_global_lock and watchdog_lock.
Only allocate a new tracker in netdev_watchdog_up() if one is
not already present.
In dev_watchdog(), ensure we don't release the tracker if the
timer was rescheduled either by dev_watchdog() itself or concurrently
by netdev_watchdog_up(). |
| In the Linux kernel, the following vulnerability has been resolved:
nfs: use nfsi->rwsem to protect traversal of the file lock list
Lingfeng identified a bug and suggested two solutions, but both appear
to have issues.
Generally, we cannot release flc_lock while iterating over the file lock
list to avoid use-after-free (UAF) problems with file locks. However,
functions like nfs_delegation_claim_locks and nfs4_reclaim_locks cannot
adhere to this rule because recover_lock or nfs4_lock_delegation_recall
may take a long time. To resolve this, NFS switches to using nfsi->rwsem
for the same protection, and nfs_reclaim_locks follows this approach.
Although nfs_delegation_claim_locks uses so_delegreturn_mutex instead,
this is inadequate since a single inode can have multiple nfs4_state
instances. Therefore, the fix is to also use nfsi->rwsem in this case.
Furthermore, after commit c69899a17ca4 ("NFSv4: Update of VFS byte range
lock must be atomic with the stateid update"), the functions
nfs4_locku_done and nfs4_lock_done also break this rule because they
call locks_lock_inode_wait without holding nfsi->rwsem. Simply adding
this protection could cause many deadlocks, so instead, the call to
locks_lock_inode_wait is moved into _nfs4_proc_setlk. Regarding the bug
fixed by commit c69899a17ca4 ("NFSv4: Update of VFS byte range
lock must be atomic with the stateid update"), it has been resolved
after commit 0460253913e5 ("NFSv4: nfs4_do_open() is incorrectly triggering
state recovery") because all slots are drained before calling
nfs4_do_reclaim, which prevents concurrent stateid changes along this path.
Also, nfs_delegation_claim_locks does not cause this concurrency either
since when _nfs4_proc_setlk is called with NFS_DELEGATED_STATE, no RPC is
sent, so nfs4_lock_done is not called. Therefore,
nfs4_lock_delegation_recall from nfs_delegation_claim_locks is the first
time the stateid is set. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix UAF in cleanup_bearer() due to premature dst_cache_destroy()
TIPC UDP media bearer teardown calls dst_cache_destroy() on its
replicast caches before calling synchronize_net() to wait for
concurrent RCU readers (transmitters) to finish:
static void cleanup_bearer(struct work_struct *work)
{
...
list_for_each_entry_safe(rcast, tmp, &ub->rcast.list, list) {
dst_cache_destroy(&rcast->dst_cache);
list_del_rcu(&rcast->list);
kfree_rcu(rcast, rcu);
}
...
dst_cache_destroy(&ub->rcast.dst_cache);
udp_tunnel_sock_release(ub->sk);
synchronize_net();
...
}
This is highly buggy because dst_cache_destroy() immediately frees the
per-CPU cache memory (free_percpu()) and releases the cached dst
entries without any synchronization.
If a concurrent transmitter (e.g., tipc_udp_xmit()) is running on another
CPU under RCU protection, it can call dst_cache_get() concurrently,
leading to:
1. Use-After-Free on the per-CPU cache pointer itself (crash).
2. "rcuref - imbalanced put()" warning if it attempts to release a
dst that was concurrently released by dst_cache_destroy().
Furthermore, calling kfree(ub) immediately after synchronize_net() without
closing the socket first (or waiting after closing it) leaves a window
where a concurrent receiver (tipc_udp_recv()) could start after
synchronize_net(), access ub, and suffer a UAF when kfree(ub) runs.
To fix this, we must defer dst_cache_destroy() and kfree(ub) until after
we have ensured that no more readers can see the bearer/socket and all
existing readers have finished:
1. Defer rcast entry destruction (both dst_cache_destroy() and kfree())
to an RCU callback using call_rcu_hurry().
Using call_rcu_hurry() ensures the dst entries are released quickly.
2. Release the bearer socket using udp_tunnel_sock_release() (stops
new receive readers).
3. Call synchronize_net() to wait for all outstanding RCU readers
(both transmit and receive) to finish.
4. Now that it is safe, call dst_cache_destroy() on the main bearer
cache, and free ub.
Note: 3) and 4) can be changed later in net-next to also use
call_rcu_hurry() and get rid of the synchronize_net() latency. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: 6lowpan: avoid untracked enable work
lowpan_enable_set() allocates a temporary work item and schedules
do_enable_set() on system_wq, then returns to debugfs. The debugfs active
operation has ended at that point, but the worker still executes module
text and manipulates enable_6lowpan and listen_chan.
bt_6lowpan_exit() removes the debugfs files and immediately closes and
puts listen_chan. It has no pointer to the queued work item, so it cannot
cancel or flush it before tearing down the state that the worker uses.
The buggy scenario involves two paths, with each column showing the order
within that path:
debugfs enable write module exit
1. lowpan_enable_set() allocates 1. bt_6lowpan_exit() removes
set_enable work the debugfs file
2. schedule_work() queues 2. bt_6lowpan_exit() closes
do_enable_set() and puts listen_chan
3. the write operation returns 3. module teardown can continue
4. do_enable_set() later runs
against stale state
Run the enable state transition synchronously in lowpan_enable_set()
instead. The simple debugfs setter can sleep, and this file already handles
the 6LoWPAN control write synchronously under the same set_lock. Once the
setter returns, debugfs removal covers the whole operation and exit can no
longer race with an untracked work item.
Validation reproduced this kernel report:
BUG: KASAN: slab-use-after-free in do_enable_set+0x113/0x2e0
Workqueue: events do_enable_set [bluetooth_6lowpan]
The buggy address belongs to the object at ffff888109cb8000 |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: 6lowpan: hold L2CAP conn across debugfs control
get_l2cap_conn() looks up an LE hci_conn under hdev protection, but
then drops that protection before reading hcon->l2cap_data and before
lowpan_control_write() later dereferences conn->hcon. A disconnect or
device close can tear down the same L2CAP connection in that window.
The buggy scenario involves two paths, with each column showing the order
within that path:
6LoWPAN control write: HCI disconnect/device close:
1. get_l2cap_conn() finds hcon 1. hci_disconn_cfm() dispatches
and hcon->l2cap_data. the L2CAP disconnect callback.
2. get_l2cap_conn() drops hdev 2. l2cap_conn_del() clears
protection and returns conn. hcon->l2cap_data and drops the
L2CAP connection reference.
3. lowpan_control_write() reads 3. hci_conn_del() removes and drops
conn->hcon. the HCI connection.
Take a reference to the L2CAP connection with
l2cap_conn_hold_unless_zero() while hdev is still locked, and drop that
reference after the debugfs command's last use of conn. This mirrors the
existing L2CAP ACL receive-side handoff and keeps the connection
dereferenceable after leaving hdev protection. Export the existing helper
so the bluetooth_6lowpan module can use the same lifetime primitive.
Validation reproduced this kernel report:
BUG: KASAN: slab-use-after-free in lowpan_control_write+0x374/0x520
The buggy address belongs to the object at ffff888111b9d000 which belongs
to the cache kmalloc-1k of size 1024
The buggy address is located 0 bytes inside of freed 1024-byte region
[ffff888111b9d000, ffff888111b9d400)
Read of size 8
Call trace:
dump_stack_lvl+0x66/0xa0
print_report+0xce/0x5f0
lowpan_control_write+0x374/0x520 (net/bluetooth/6lowpan.c:1131)
srso_alias_return_thunk+0x5/0xfbef5
__virt_addr_valid+0x19f/0x330
kasan_report+0xe0/0x110
__debugfs_file_get+0xf7/0x400
full_proxy_write+0x9e/0xd0
vfs_write+0x1b0/0x810
ksys_write+0xd2/0x170
dnotify_flush+0x32/0x220
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Allocated by task stack:
kasan_save_stack+0x33/0x60
kasan_save_track+0x17/0x60
__kasan_kmalloc+0xaa/0xb0
l2cap_conn_add+0x45/0x520
l2cap_chan_connect+0xac6/0xd90
l2cap_sock_connect+0x216/0x350
__sys_connect+0x101/0x130
__x64_sys_connect+0x40/0x50
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task stack:
kasan_save_stack+0x33/0x60
kasan_save_track+0x17/0x60
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x5f/0x80
kfree+0x313/0x590
hci_conn_hash_flush+0xc0/0x140
hci_dev_close_sync+0x41a/0xb00
hci_dev_close+0x12f/0x160
hci_sock_ioctl+0x157/0x570
sock_do_ioctl+0xf7/0x210
sock_ioctl+0x32f/0x490
__x64_sys_ioctl+0xc7/0x110
do_syscall_64+0x115/0x6a0 (arch/x86/entry/syscall_64.c:87)
entry_SYSCALL_64_after_hwframe+0x77/0x7f
kasan_record_aux_stack+0xa7/0xc0
insert_work+0x32/0x100
__queue_work+0x262/0xa60
queue_work_on+0xad/0xb0
l2cap_connect_cfm+0x4ef/0x670
hci_le_remote_feat_complete_evt+0x247/0x430
hci_event_packet+0x360/0x6f0
hci_rx_work+0x2ae/0x7a0
process_one_work+0x4fd/0xbc0
worker_thread+0x2d8/0x570
kthread+0x1ad/0x1f0
ret_from_fork+0x3c9/0x540
ret_from_fork_asm+0x1a/0x30 |
| In the Linux kernel, the following vulnerability has been resolved:
net/liquidio: drop cached VF pci_dev LUT
The PF SR-IOV enable path caches VF pci_dev pointers in
dpiring_to_vfpcidev_lut[] by iterating with pci_get_device(). Those
entries do not own a reference, because the iterator drops the previous
device reference on each step. The cached pointer is then dereferenced
later when handling OCTEON_VF_FLR_REQUEST.
Replace the cached VF mapping with runtime lookup on the mailbox DPI
ring: derive the VF index from q_no, resolve the VF via exported PCI
IOV helpers, validate it with the PF pointer and VF ID, then issue
pcie_flr() and drop the reference with pci_dev_put(). Remove the
unused VF lookup table initialization and cleanup. |
| In the Linux kernel, the following vulnerability has been resolved:
mtd: maps: vmu-flash: fix fault in unaligned fixup
Use kzalloc_obj() / kzalloc_objs() to allocate the memcard structs,
instead of kmalloc_obj() / kmalloc_objs() to prevent access to
uninitialized data.
Fixes runtime error: Fault in unaligned fixup: 0000 [#1] at
mtd_get_fact_prot_info. |
| In the Linux kernel, the following vulnerability has been resolved:
riscv: probes: save original sp in rethook trampoline
Reading a word from the stack in a kretprobe crashes a risc-v kernel.
$ cd /sys/kernel/tracing/
$ echo 'r n_tty_write $stack0' > dynamic_events
$ echo 1 > events/kprobes/enable
Unable to handle kernel paging request at virtual address 0000000200000128
...
[<ffffffff80016d16>] regs_get_kernel_stack_nth+0x26/0x38
[<ffffffff80177196>] process_fetch_insn+0x3ee/0x760
[<ffffffff80177836>] kretprobe_trace_func+0x116/0x1f0
[<ffffffff8017795a>] kretprobe_dispatcher+0x4a/0x58
[<ffffffff8013572e>] kretprobe_rethook_handler+0x5e/0x90
[<ffffffff80180838>] rethook_trampoline_handler+0x70/0x108
[<ffffffff8001ba32>] arch_rethook_trampoline_callback+0x12/0x1c
[<ffffffff8001ba84>] arch_rethook_trampoline+0x48/0x94
[<ffffffff8067872a>] tty_write+0x1a/0x30
In regs_get_kernel_stack_nth, regs->sp contains an arbitrary value.
arch_rethook_trampoline saves the registers from the probed function in a
struct pt_regs. sp is not saved. Instead, sp is decremented for
arch_rethook_trampoline's local stack.
Fix this crash and save the original sp along with the other registers.
Use a0 as a temporary register, it is overwritten anyway.
[pjw@kernel.org: added Fixes tag; cc'ed stable] |
| In the Linux kernel, the following vulnerability has been resolved:
pmdomain: imx: Fix i.MX8MP VC8000E power up sequence
Per errata[1]:
ERR050531: VPU_NOC power down handshake may hang during VC8000E/VPUMIX
power up/down cycling.
Description: VC8000E reset de-assertion edge and AXI clock may have a
timing issue.
Workaround: Set bit2 (vc8000e_clk_en) of BLK_CLK_EN_CSR to 0 to gate off
both AXI clock and VC8000E clock sent to VC8000E and AXI clock sent to
VPU_NOC m_v_2 interface during VC8000E power up(VC8000E reset is
de-asserted by HW)
Add a bool variable is_errata_err050531 in
'struct imx8m_blk_ctrl_domain_data' to represent whether the workaround
is needed. If is_errata_err050531 is true, first clear the clk before
powering up gpc, then enable the clk after powering up gpc.
[1] https://www.nxp.com/webapp/Download?colCode=IMX8MP_1P33A |
| In the Linux kernel, the following vulnerability has been resolved:
LoongArch: Fix address space mismatch in kexec command line lookup
When searching the loaded segments for the "kexec" command line marker,
the kexec_load(2) path (file_mode == 0) passes the user-space segment
buffer straight to strncmp() through a bogus (char __user *) cast. This
dereferences a user pointer in kernel context, which is wrong and is
flagged by sparse:
arch/loongarch/kernel/machine_kexec.c:84:51: sparse: incorrect type in
argument 2 (different address spaces) @@ expected char const * @@ got
char [noderef] __user *
Here copy the marker-sized prefix of each segment into a small on-stack
buffer with copy_from_user() before comparing, and skip segments that
fault. The subsequent copy_from_user() that stages the full command line
into the safe area is left unchanged. |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: fix stale skb->prev after async crypto steals a GSO segment
skb_gso_segment() leaves the segment list head with ->prev pointing at
the last segment, an invariant validate_xmit_skb_list() relies on when
it sets its tail pointer (tail = skb->prev).
When validate_xmit_xfrm() walks a GSO list and some segments are stolen
by async crypto (->xmit() returns -EINPROGRESS), those segments are
unlinked from the list but the head ->prev is never updated. If the
last segment is the one stolen, the returned head still has ->prev
pointing at it, even though it is now owned by the crypto engine and may
be freed. validate_xmit_skb_list() later does tail->next = skb, writing
through that stale pointer -- a use-after-free.
Repoint skb->prev at the last retained segment before returning. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: defer link RX stats percpu free to RCU
sta_remove_link() frees a removed MLO link's RX stats percpu buffer right
away, but defers only the link container to RCU:
sta_info_free_link(&alloc->info);
kfree_rcu(alloc, rcu_head);
The RX fast path reads link_sta under rcu_read_lock and writes the percpu
stats. A reader that resolved link_sta before the removal keeps the
pointer. The container stays alive from the kfree_rcu, so the read still
works. But the percpu block it points to is already freed. This needs
uses_rss. That is when pcpu_rx_stats exists.
The full STA teardown frees the deflink stats only after
synchronize_net(). The link removal path had no such barrier. The race is
hard to win in practice, but the free should still wait for RCU.
Free the link together with its data from a single RCU callback, so the
percpu block is reclaimed only after readers drain. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix UAF in sock clone early bailouts
Similar to recent commit 9b51a6155d14 ("bpf,fork: wipe ->bpf_storage
before bailouts that access it"), sk_clone() performs an initial
shallow copy of the socket field ->sk_bpf_storage via sock_copy()
for the cloned socket newsk.
If sk_clone() bails out early (e.g. if sk_filter_charge() fails) prior
to calling bpf_sk_storage_clone(), newsk->sk_bpf_storage still points
to the parent socket's BPF local storage. When newsk is subsequently
freed via sk_free(), the deallocation path (__sk_destruct() ->
bpf_sk_storage_free()) destroys the parent socket's BPF local storage,
leading to a use-after-free (UAF) on the parent socket.
Fix this by resetting newsk->sk_bpf_storage to NULL immediately after
sock_copy() in sk_clone(), and remove the now redundant initialization
from bpf_sk_storage_clone(). |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: serialize udp bearer replicast list updates
tipc_udp_rcast_add() and cleanup_bearer() both update ub->rcast.list with
list_add_rcu() / list_del_rcu(), but nothing serializes them. The add runs
from the encap receive softirq (via tipc_udp_rcast_disc()) without
rtnl_lock(), so it can race the cleanup delete and corrupt the list:
list_del corruption. prev->next should be ffff8880298d7ab8,
but was ffff88802449ad38. (prev=ffff888027e3ec98)
kernel BUG at lib/list_debug.c:62!
RIP: __list_del_entry_valid_or_report+0x17a/0x200
Workqueue: events cleanup_bearer
Call Trace:
cleanup_bearer (net/tipc/udp_media.c:811)
process_one_work (kernel/workqueue.c:3302)
worker_thread (kernel/workqueue.c:3466)
The bearer can be enabled from an unprivileged user namespace, as the
TIPCv2 generic-netlink ops carry no GENL_ADMIN_PERM.
Add a spinlock to struct udp_bearer and take it around the list_add_rcu()
in tipc_udp_rcast_add() and the list_del_rcu() loop in cleanup_bearer() so
the two writers can no longer corrupt the list.
Reject a duplicate peer under the same lock before allocating, and remove
tipc_udp_is_known_peer(). The old lockless pre-check in
tipc_udp_rcast_disc() was racy: two softirqs discovering the same peer
could both find it absent and add it twice.
cleanup_bearer() runs from a workqueue after tipc_udp_disable() clears the
bearer's up bit, so an encap softirq can still reach tipc_udp_rcast_add()
and add a peer after cleanup_bearer() has already emptied the list, leaking
that entry when the bearer is freed. Mark the bearer disabled under
rcast_lock once the list is emptied and refuse further additions. |
