| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix UAF in smc_cdc_rx_handler() by pinning the socket
smc_cdc_rx_handler() looks up the connection by token under the link
group's conns_lock, drops the lock, and then dereferences conn and the
smc_sock derived from it, ending in sock_hold(&smc->sk) inside
smc_cdc_msg_recv(). No reference is held across the lock release.
The only reference pinning the socket while the connection is
discoverable in the link group is taken in smc_lgr_register_conn()
(sock_hold) and dropped in __smc_lgr_unregister_conn() (sock_put), both
under conns_lock. Once the handler drops conns_lock, a concurrent
close() -> smc_release() -> smc_conn_free() -> smc_lgr_unregister_conn()
can drop that reference and free the smc_sock, so the handler's later
sock_hold() runs on freed memory:
WARNING: lib/refcount.c:25 at refcount_warn_saturate
Workqueue: rxe_wq do_work
refcount_warn_saturate (lib/refcount.c:25)
smc_cdc_msg_recv (net/smc/smc_cdc.c:430)
smc_cdc_rx_handler (net/smc/smc_cdc.c:502)
smc_wr_rx_tasklet_fn (net/smc/smc_wr.c:445)
tasklet_action_common (kernel/softirq.c:938)
handle_softirqs (kernel/softirq.c:622)
Kernel panic - not syncing: panic_on_warn set
Only SMC-R is affected. The SMC-D receive tasklet is stopped by
tasklet_kill(&conn->rx_tsklet) in smc_conn_free() before the connection
is unregistered, so it cannot run concurrently with the free.
Take the socket reference while still holding conns_lock, so the
registration reference can no longer be the last one, and drop it once
the handler is done. |
| In the Linux kernel, the following vulnerability has been resolved:
rpmsg: core: fix race in driver_override_show() and use core helper
The driver_override_show function reads the driver_override string
without holding the device_lock. However, the store function modifies
and frees the string while holding the device_lock. This creates a race
condition where the string can be freed by the store function while
being read by the show function, leading to a use-after-free.
To fix this, replace the rpmsg_string_attr macro with explicit show and
store functions. The new driver_override_store uses the standard
driver_set_override helper. Since the introduction of
driver_set_override, the comments in include/linux/rpmsg.h have stated
that this helper must be used to set or clear driver_override, but the
implementation was not updated until now.
Because driver_set_override modifies and frees the string while holding
the device_lock, the new driver_override_show now correctly holds the
device_lock during the read operation to prevent the race.
Additionally, since rpmsg_string_attr has only ever been used for
driver_override, removing the macro simplifies the code. |
| In the Linux kernel, the following vulnerability has been resolved:
HID: appleir: fix UAF on pending key_up_timer in remove()
appleir_remove() runs hid_hw_stop() before timer_delete_sync().
hid_hw_stop() synchronously unregisters the HID input device via
hid_disconnect() -> hidinput_disconnect() -> input_unregister_device(),
which drops the last reference and frees the underlying input_dev when
no userspace handle holds it open.
key_up_tick() reads appleir->input_dev and calls input_report_key() /
input_sync() on it. The timer is armed from appleir_raw_event() with
a HZ/8 (~125 ms) timeout on every keydown and key-repeat report. If a
key was pressed shortly before the device is disconnected, the timer
can fire after hid_hw_stop() has freed input_dev but before the
teardown drains it.
A simple reorder is not sufficient. Putting the timer drain first
still leaves a window where a USB URB completion (raw_event) running
during hid_hw_stop() can call mod_timer() and re-arm the timer, which
then fires after hidinput_disconnect() has freed input_dev. The same
URB-completion window also lets raw_event() reach key_up(), key_down()
and battery_flat() directly, all of which dereference
appleir->input_dev.
Introduce a 'removing' flag on struct appleir, gated by the existing
spinlock. appleir_remove() sets the flag under the lock and then
shuts down the timer with timer_shutdown_sync(), which both drains any
in-flight callback and permanently disables further mod_timer() calls.
appleir_raw_event() and key_up_tick() bail out early if the flag is
set, so no path can arm or run the timer, or dereference
appleir->input_dev, after remove() has started tearing down.
The keyrepeat and flatbattery branches of appleir_raw_event()
previously called into the input layer without holding the spinlock;
take it now so the flag check is well-defined. This incidentally
closes a pre-existing read-side race on appleir->current_key in the
keyrepeat branch.
This bug is structurally a sibling of commit 4db2af929279 ("HID:
appletb-kbd: fix UAF in inactivity-timer cleanup path") and has been
present since the driver was introduced. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_api: use RCU with deferred freeing for action lifecycle
When NEWTFILTER and DELFILTER are run concurrently it is possible to create a
race with an associated action.
Let's illustrate with CPU0 running NEWTFILTER and CPU1 running DELFILTER:
0: mutex_lock() <-- holds the idr lock
0: rcu_read_lock()
0: p = idr_find(idr, index) <-- action p is valid (RCU protects IDR)
0: mutex_unlock() <-- releases the idr lock
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index) <-- Action removed from IDR
1: mutex_unlock() <-- mutex released allowing us to delete the action
1: tcf_action_cleanup(p); kfree(p) <-- Kfrees p immediately, no deferral
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- ouch, UAF p points to freed memory
This patch fixes the race condition between NEWTFILTER and DELFILTER by
adding struct rcu_head to tc_action used in the deferral and introducing a
call_rcu() in the delete path to defer the final kfree().
Note: this is a revert of commit d7fb60b9cafb ("net_sched: get rid of tcfa_rcu")
but also modernization/simplification to directly use kfree_rcu().
Let's illustrate the new restored code path:
0: rcu_read_lock()
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index)
1: mutex_unlock()
1: call_rcu(&p->tcfa_rcu, tcf_action_rcu_free) <-- defer kfree after grace period
0: p = idr_find(idr, index)
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- fails, refcnt already 0
1: rcu_read_unlock() <-- release so freeing can run after grace period
After CPU1 calls idr_remove(), the object is no longer reachable through the IDR.
CPU0's subsequent idr_find() will return NULL, and even if it still held a
stale pointer, the immediate kfree() is now deferred until after the RCU grace
period, so no UAF can occur. |
| In the Linux kernel, the following vulnerability has been resolved:
mm: shrinker: fix shrinker_info teardown race with expansion
expand_shrinker_info() iterates all visible memcgs under shrinker_mutex,
including memcgs that have not finished ->css_online() yet.
Once pn->shrinker_info has been published, teardown must stay serialized
with expand_shrinker_info() until that memcg is either fully online or no
longer visible to iteration. Today alloc_shrinker_info() breaks that rule
by dropping shrinker_mutex before freeing a partially initialized
shrinker_info array, which may cause the following race:
CPU0 CPU1
==== ====
css_create
--> list_add_tail_rcu(&css->sibling, &parent_css->children);
online_css
--> mem_cgroup_css_online
--> alloc_shrinker_info
--> alloc node0 info
rcu_assign_pointer(C->node0->shrinker_info, old0)
alloc node1 info -> FAIL -> goto err
mutex_unlock(shrinker_mutex)
shrinker_alloc()
--> shrinker_memcg_alloc
--> mutex_lock(shrinker_mutex)
expand_shrinker_info
--> mem_cgroup_iter see the memcg
expand_one_shrinker_info
--> old0 = C->node0->shrinker_info
memcpy(new->unit, old0->unit, ...);
free_shrinker_info
--> kvfree(old0);
/* double free !! */
kvfree_rcu(old0, rcu);
The same problem exists later in mem_cgroup_css_online(). If
alloc_shrinker_info() succeeds but a subsequent objcg allocation fails,
the free_objcg -> free_shrinker_info() unwind path tears down the already
published pn->shrinker_info arrays without shrinker_mutex. The
expand_one_shrinker_info() can race with that teardown in the same way,
leading to use-after-free or double-free of the old shrinker_info.
Fix this by serializing shrinker_info teardown with shrinker_mutex, and by
keeping alloc_shrinker_info() error cleanup inside the locked section. |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: llcp: Fix use-after-free race in nfc_llcp_recv_cc()
A race condition exists in the NFC LLCP connection state machine where
the connection acceptance packet (CC) can be processed concurrently with
socket release. This can lead to a use-after-free of the socket object.
When nfc_llcp_recv_cc() moves the socket from the connecting_sockets
list to the sockets list, it does so without holding the socket lock.
If llcp_sock_release() is executing concurrently, it might have already
unlinked the socket and dropped its references, which can result in
nfc_llcp_recv_cc() linking a freed socket into the live list.
Fix this by holding lock_sock() during the state transition and list
movement in nfc_llcp_recv_cc(). After acquiring the lock, check if
the socket is still hashed to ensure it hasn't already been unlinked
and marked for destruction by the release path. This aligns the locking
pattern with recv_hdlc() and recv_disc(). |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: seq: Serialize UMP output teardown with event_input
seq_ump_process_event() borrows client->out_rfile.output without
synchronizing with the first-open and last-close transition in
seq_ump_client_open() and seq_ump_client_close().
The last output unuse can therefore drop opened[STR_OUT] to zero and
release the rawmidi file while an in-flight event_input callback is still
inside snd_rawmidi_kernel_write(). That leaves the rawmidi substream
runtime exposed to teardown before the write path has taken its own
buffer reference.
Add a per-client rwlock for the event_input-visible output file. Publish
a newly opened output file under the write side, and hold the read side
from the output lookup through snd_rawmidi_kernel_write(). The last
output close copies and clears the visible output file under the write
side, then drops the lock and releases the saved rawmidi file. Use
IRQ-safe rwlock guards because event_input can also be reached from
atomic sequencer delivery.
The buggy scenario involves two paths, with each column showing the
order within that path:
path A label: event_input path path B label: last unuse path
1. seq_ump_process_event() reads 1. seq_ump_client_close()
client->out_rfile.output. drops opened[STR_OUT] to zero.
2. snd_rawmidi_kernel_write1() 2. snd_rawmidi_kernel_release()
has not yet pinned runtime. closes the output file.
3. The writer continues using 3. close_substream() frees
the borrowed substream. substream->runtime.
This keeps the output substream and runtime alive for the full
event_input write while keeping rawmidi release outside the rwlock.
KASAN reproduced this as a slab-use-after-free in
snd_rawmidi_kernel_write1(), with allocation through
seq_ump_use()/snd_seq_port_connect() and free through
seq_ump_unuse()/snd_seq_port_disconnect().
Validation reproduced this kernel report:
KASAN slab-use-after-free in snd_rawmidi_kernel_write1+0x9d/0x400
RIP: 0033:0x7f5528af837f
Read of size 8
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_rawmidi_kernel_write1+0x9d/0x400 (?:?)
__asan_load8+0x82/0xb0 (?:?)
update_stack_state+0x1ef/0x2d0 (?:?)
snd_rawmidi_kernel_write+0x1a/0x20 (?:?)
seq_ump_process_event+0xd4/0x120 (sound/core/seq/seq_ump_client.c:82)
__snd_seq_deliver_single_event+0x8a/0xe0 (?:?)
snd_seq_deliver_from_ump+0x2b2/0xd60 (?:?)
lock_acquire+0x14e/0x2e0 (?:?)
find_held_lock+0x31/0x90 (?:?)
snd_seq_port_use_ptr+0xa6/0xe0 (?:?)
__kasan_check_write+0x18/0x20 (?:?)
do_raw_read_unlock+0x32/0xa0 (?:?)
_raw_read_unlock+0x26/0x50 (?:?)
snd_seq_deliver_single_event+0x45c/0x4b0 (?:?)
snd_seq_deliver_event+0x10d/0x1b0 (?:?)
snd_seq_client_enqueue_event+0x192/0x240 (?:?)
snd_seq_write+0x2cd/0x450 (?:?)
apparmor_file_permission+0x20/0x30 (?:?)
security_file_permission+0x51/0x60 (?:?)
vfs_write+0x1ce/0x850 (?:?)
__fget_files+0x12b/0x220 (?:?)
lock_release+0xc8/0x2a0 (?:?)
__rcu_read_unlock+0x74/0x2d0 (?:?)
__fget_files+0x135/0x220 (?:?)
ksys_write+0x15a/0x180 (?:?)
rcu_is_watching+0x24/0x60 (?:?)
__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:
Bluetooth: hci_sync: fix UAF in hci_le_create_cis_sync
hci_le_create_cis_sync() dereferences conn->conn_timeout after releasing
both rcu_read_lock() and hci_dev_lock(hdev). The conn pointer was
obtained from an RCU-protected iteration over hdev->conn_hash.list and
is not valid once these locks are dropped. A concurrent disconnect can
free the hci_conn between the unlock and the dereference, causing a
use-after-free read.
The cancellation mechanism in hci_conn_del() cannot prevent this because
hci_le_create_cis_pending() queues hci_create_cis_sync with data=NULL:
hci_cmd_sync_queue(hdev, hci_create_cis_sync, NULL, NULL);
While hci_conn_del() dequeues with data=conn:
hci_cmd_sync_dequeue(hdev, NULL, conn, NULL);
Since NULL != conn, the lookup in _hci_cmd_sync_lookup_entry() never
matches, and the pending work item is not cancelled.
Fix this by saving conn->conn_timeout into a local variable while the
locks are still held, so the stale conn pointer is never dereferenced
after unlock.
This is the same class of bug as the one fixed by commit 035c25007c9e
("Bluetooth: hci_sync: Fix UAF on le_read_features_complete") which
addressed the identical pattern in a different function.
This vulnerability was identified using 0sec.ai, an open-source
automated security auditing platform (https://github.com/0sec-labs). |
| In the Linux kernel, the following vulnerability has been resolved:
irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT
On PREEMPT_RT, non-HARD irq_work runs in per-CPU kthreads via
run_irq_workd(), so irq_work_sync() uses rcuwait() to wait for BUSY==0.
After irq_work_single() clears BUSY via atomic_cmpxchg(), it still
dereferences @work for irq_work_is_hard() and rcuwait_wake_up().
An irq_work_sync() caller on another CPU that enters after BUSY is cleared
can observe BUSY==0 immediately, return, and free the work before those
accesses complete — causing a use-after-free.
Fix this by wrapping run_irq_workd() in guard(rcu)() so that the entire
irq_work_single() execution is within an RCU read-side critical
section. Then add synchronize_rcu() in irq_work_sync() after
rcuwait_wait_event() to ensure the caller waits for the RCU grace period
before returning, preventing premature frees. |
| In the Linux kernel, the following vulnerability has been resolved:
ovpn: tcp - use cached peer pointer in ovpn_tcp_close()
ovpn_tcp_close() loads the ovpn_socket via rcu_dereference_sk_user_data()
under rcu_read_lock(), takes a reference on sock->peer, caches the peer
pointer in a local, and drops the read lock. It then passes sock->peer
(rather than the cached local) to ovpn_peer_del(), re-dereferencing the
ovpn_socket after the RCU read section has ended.
Unlike ovpn_tcp_sendmsg(), which uses the same "load under RCU, use
after unlock" pattern but is protected by lock_sock() held across the
function, ovpn_tcp_close() runs without the socket lock: inet_release()
invokes sk_prot->close() without taking lock_sock first.
ovpn_socket_release() can therefore complete its kref_put -> detach ->
synchronize_rcu -> kfree(sock) sequence concurrently, in the window
after ovpn_tcp_close() drops rcu_read_lock() but before it dereferences
sock->peer. The synchronize_rcu() in ovpn_socket_release() protects
readers that use the dereferenced pointer inside the RCU read section,
not those that escape the pointer to a local and use it afterwards.
A reproducer follows the pattern of commit 94560267d6c4 ("ovpn: tcp -
don't deref NULL sk_socket member after tcp_close()"): trigger a peer
removal (keepalive expiration or netlink OVPN_CMD_DEL_PEER) at the same
moment userspace closes the TCP fd. That commit fixed the detach-side
of the same race window; this one fixes the close-side at a different
victim.
Tighten the entry block to read sock->peer exactly once into the cached
peer local, and route all subsequent uses (the hold check, the
ovpn_peer_del() call, and the prot->close() invocation) through that
local. sock->peer is only ever written once in ovpn_socket_new() under
lock_sock(), before rcu_assign_sk_user_data() publishes the ovpn_socket,
and is never reassigned afterwards - but the previous multi-read pattern
made that invariant implicit rather than explicit. The same multi-read
shape exists in ovpn_tcp_recvmsg(), ovpn_tcp_sendmsg(),
ovpn_tcp_data_ready() and ovpn_tcp_write_space(); those will be cleaned
up via a dedicated helper in a follow-up net-next series. |
| In the Linux kernel, the following vulnerability has been resolved:
fhandle: fix UAF due to unlocked ->mnt_ns read in may_decode_fh()
may_decode_fh() accesses mount::mnt_ns without holding any locks; that
means the mount can concurrently be unmounted, and the mnt_namespace can
concurrently be freed after an RCU grace period.
This race can happens as follows, assuming that the mount point was
created by open_tree(..., OPEN_TREE_CLONE):
thread 1 thread 2 RCU
__do_sys_open_by_handle_at
do_handle_open
handle_to_path
may_decode_fh
is_mounted
[mount::mnt_ns access]
[mount::mnt_ns access]
__do_sys_close
fput_close_sync
__fput
dissolve_on_fput
umount_tree
class_namespace_excl_destructor
namespace_unlock
free_mnt_ns
mnt_ns_tree_remove
call_rcu(mnt_ns_release_rcu)
mnt_ns_release_rcu
mnt_ns_release
kfree
[mnt_namespace::user_ns access] **UAF**
Fix it by taking rcu_read_lock() around the mount::mnt_ns access, like
in __prepend_path().
Additionally, document the semantics of mount::mnt_ns, and use WRITE_ONCE()
for writers that can race with lockless readers.
This bug is unreachable unless one of the following is set:
- CONFIG_PREEMPTION
- CONFIG_RCU_STRICT_GRACE_PERIOD
because it requires an RCU grace period to happen during a syscall without
an explicit preemption.
This doesn't seem to have interesting security impact; worst-case, it could
leak the result of an integer comparison to userspace (from the level
check in cap_capable()), cause an endless loop, or crash the kernel by
dereferencing an invalid address. |
| FreeRDP before 3.22.0 contains a use-after-free vulnerability in dvcman_channel_close and dvcman_call_on_receive due to improper synchronization of channel_callback access. A malicious RDP server can trigger a race condition by sending DYNVC_DATA and DYNVC_CLOSE messages concurrently, causing heap-use-after-free in the drdynvc client thread and potentially enabling remote code execution or denial of service. |
| Oj (Optimized JSON) is a JSON parser and Object marshaller packaged as a Ruby gem. Prior to 3.17.2, Oj::Doc iterators (each_value, each_child, each_leaf) were vulnerable to a heap use-after-free. When a Ruby block yielded during iteration calls doc.close or d.close, the document's heap memory is freed while the C iterator is still running. When control returns from the block, the iterator reads from the freed region, producing a use-after-free accessible from pure Ruby. This issue has been fixed in version 3.17.2. |
| A vulnerability was found in systemd-coredump. This flaw allows an attacker to force a SUID process to crash and replace it with a non-SUID binary to access the original's privileged process coredump, allowing the attacker to read sensitive data, such as /etc/shadow content, loaded by the original process.
A SUID binary or process has a special type of permission, which allows the process to run with the file owner's permissions, regardless of the user executing the binary. This allows the process to access more restricted data than unprivileged users or processes would be able to. An attacker can leverage this flaw by forcing a SUID process to crash and force the Linux kernel to recycle the process PID before systemd-coredump can analyze the /proc/pid/auxv file. If the attacker wins the race condition, they gain access to the original's SUID process coredump file. They can read sensitive content loaded into memory by the original binary, affecting data confidentiality. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: max77705: Free allocated workqueue and fix removal order
Use devm interface for allocating workqueue to fix two bugs at the same
time:
1. Driver leaks the memory on remove(), because the workqueue is not
destroyed.
2. Driver allocates workqueue and then registers interrupt handlers
with devm interface. This means that probe error paths will not use a
reversed order, but first destroy the workqueue and then, via devm
release handlers, free the interrupt.
The interrupt handler schedules work on this exact workqueue, thus if
interrupt is hit in this short time window - after destroying
workqueue, but before devm() frees the interrupt - the schedulled
work will lead to use of freed memory.
Change is not equivalent in the workqueue itself: use non-legacy API
which does not set (__WQ_LEGACY | WQ_MEM_RECLAIM). The workqueue is
used to update power supply (power_supply_changed()) status, thus there
is no point to run it for memory reclaim. Note that dev_name() is not
directly used in second argument to prevent possible unlikely parsing
any "%" character in device name as format. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: timer: Fix UAF at snd_timer_user_params()
At releasing a timer object, e.g. when a userspace timer
(CONFIG_SND_UTIMER) gets closed and snd_timer_free() is called, it
tries to detach the timer instances and release the resources.
However, it's still possible that other in-flight tasks are holding
the timer instance where the to-be-deleted timer object is associated,
and this may lead to racy accesses.
Fortunately, most of ioctls dealing with the timer instance list
already have the protection with register_mutex, and this also avoids
such races. But, SNDRV_TIMER_IOCTL_PARAMS isn't protected, hence the
concurrent ioctl may lead to use-after-free.
This patch just adds the guard with register_mutex to protect
snd_timer_user_params() for covering the code path as a quick
workaround. It's no hot-path but rather a rarely issued ioctl, so the
performance penalty doesn't matter. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free from async crypto on Qualcomm crypto engine
ksmbd_crypt_message() sets a NULL completion callback on AEAD requests
and does not handle the -EINPROGRESS return code from async hardware
crypto engines like the Qualcomm Crypto Engine (QCE). When QCE returns
-EINPROGRESS, ksmbd treats it as an error and immediately frees the
request while the hardware DMA operation is still in flight. The DMA
completion callback then dereferences freed memory, causing a NULL
pointer crash:
pc : qce_skcipher_done+0x24/0x174
lr : vchan_complete+0x230/0x27c
...
el1h_64_irq+0x68/0x6c
ksmbd_free_work_struct+0x20/0x118 [ksmbd]
ksmbd_exit_file_cache+0x694/0xa4c [ksmbd]
Use the standard crypto_wait_req() pattern with crypto_req_done() as
the completion callback, matching the approach used by the SMB client
in fs/smb/client/smb2ops.c. This properly handles both synchronous
engines (immediate return) and async engines (-EINPROGRESS followed
by callback notification). |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Free reuseport cBPF prog after RCU grace period.
Eulgyu Kim reported the splat below with a repro. [0]
The repro sets up a UDP reuseport group with a cBPF prog and
replaces it with a new one while another thread is sending
a UDP packet to the group.
The reuseport prog is freed by sk_reuseport_prog_free().
bpf_prog_put() is called for "e"BPF prog to destruct through
multiple stages while cBPF prog is freed immediately by
bpf_release_orig_filter() and bpf_prog_free().
If a reuseport prog is detached from the setsockopt() path
(reuseport_attach_prog() or reuseport_detach_prog()),
sk_reuseport_prog_free() is called without waiting for RCU
readers to complete, resulting in various bugs.
Let's defer freeing the reuseport cBPF prog after one RCU
grace period.
Note "e"BPF prog is safe as is unless the fast path starts
to touch fields destroyed in bpf_prog_put_deferred() and
__bpf_prog_put_noref().
[0]:
BUG: KASAN: vmalloc-out-of-bounds in reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
Read of size 4 at addr ffffc9000051e004 by task slowme/10208
CPU: 6 UID: 1000 PID: 10208 Comm: slowme Not tainted 7.0.0-geb7ac95ff75e #32 PREEMPT(full)
Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
udp4_lib_lookup2+0x3bc/0x950 net/ipv4/udp.c:495
__udp4_lib_lookup+0x768/0xe20 net/ipv4/udp.c:723
__udp4_lib_lookup_skb+0x297/0x390 net/ipv4/udp.c:752
__udp4_lib_rcv+0x1312/0x2620 net/ipv4/udp.c:2752
ip_protocol_deliver_rcu+0x282/0x440 net/ipv4/ip_input.c:207
ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6181 [inline]
__netif_receive_skb net/core/dev.c:6294 [inline]
process_backlog+0xaa4/0x1960 net/core/dev.c:6645
__napi_poll+0xae/0x340 net/core/dev.c:7709
napi_poll net/core/dev.c:7772 [inline]
net_rx_action+0x5d7/0xf50 net/core/dev.c:7929
handle_softirqs+0x22b/0x870 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
</IRQ>
<TASK>
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x1dd7/0x3710 net/core/dev.c:4890
neigh_output include/net/neighbour.h:556 [inline]
ip_finish_output2+0xca9/0x1070 net/ipv4/ip_output.c:237
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
ip_send_skb+0x45/0xc0 net/ipv4/ip_output.c:1508
udp_send_skb+0xb04/0x1510 net/ipv4/udp.c:1195
udp_sendmsg+0x1a71/0x2350 net/ipv4/udp.c:1485
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x554/0x680 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x160/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x415a2d
Code: b3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6bc31e41e8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f6bc31e4cdc RCX: 0000000000415a2d
RDX: 0000000000000001 RSI: 00007f6bc31e421f RDI: 0000000000000003
RBP: 00007f6bc31e4240 R08: 00007f6bc31e4220 R09: 0000000000000010
R10: 0000000000000000 R11:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()
rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,
but returns the selected listener after dropping that lock without
taking a reference. rfcomm_connect_ind() then locks the listener,
queues a child socket on it, and may notify it after unlocking it.
The buggy scenario involves two paths, with each column showing the
order within that path:
rfcomm_connect_ind(): listener close:
1. Find parent in 1. close() enters
rfcomm_get_sock_by_channel() rfcomm_sock_release().
2. Drop rfcomm_sk_list.lock 2. rfcomm_sock_shutdown()
without pinning parent. closes the listener.
3. Call lock_sock(parent) and 3. rfcomm_sock_kill()
bt_accept_enqueue(parent, unlinks and puts parent.
sk, true).
4. Read parent flags and may 4. parent can be freed.
call sk_state_change().
If close wins the race, parent can be freed before
rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the
deferred-setup callback.
Take a reference on the listener before leaving rfcomm_sk_list.lock.
After lock_sock() succeeds, recheck that it is still in BT_LISTEN
before queueing a child, cache the deferred-setup bit while the parent
is locked, and drop the reference after the last parent use.
KASAN reported a slab-use-after-free in lock_sock_nested() from
rfcomm_connect_ind(), with the freeing stack going through
rfcomm_sock_kill() and rfcomm_sock_release(). |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()
Fix the race by pruning the bin while still holding xfrm_policy_lock,
before dropping it. Use __xfrm_policy_inexact_prune_bin() directly since
the lock is already held. The wrapper xfrm_policy_inexact_prune_bin()
becomes unused and is removed.
Race:
CPU0 (XFRM_MSG_DELPOLICY) CPU1 (XFRM_MSG_NEWSPDINFO)
========================== ==========================
xfrm_policy_bysel_ctx():
spin_lock_bh(xfrm_policy_lock)
bin = xfrm_policy_inexact_lookup()
__xfrm_policy_unlink(pol)
spin_unlock_bh(xfrm_policy_lock)
xfrm_policy_kill(ret)
// wide window, lock not held
xfrm_hash_rebuild():
spin_lock_bh(xfrm_policy_lock)
__xfrm_policy_inexact_flush():
kfree_rcu(bin) // bin freed
spin_unlock_bh(xfrm_policy_lock)
xfrm_policy_inexact_prune_bin(bin)
// UAF: bin is freed |