| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix UAF in tipc_l2_send_msg()
Syzbot reported a slab-use-after-free in ipvlan_hard_header() when
called from tipc_l2_send_msg().
The root cause is that tipc_disable_l2_media() calls synchronize_net()
while b->media_ptr is still valid. This allows concurrent RCU readers
to obtain the device pointer after synchronize_net() has finished.
The pointer is cleared later in bearer_disable(), but without any
subsequent synchronization, allowing the device to be freed while
still in use by readers.
Fix this by clearing b->media_ptr in tipc_disable_l2_media() before
calling synchronize_net().
This is safe to do now because the call order in bearer_disable()
was reversed in 0d051bf93c06 ("tipc: make bearer packet filtering generic")
to call tipc_node_delete_links() (which needs the pointer) before
disable_media().
https: //lore.kernel.org/netdev/6a2c1007.428ffe26.258b27.015d.GAE@google.com/T/#u |
| In the Linux kernel, the following vulnerability has been resolved:
dmaengine: Fix possible use after free
In dma_release_channel(), check chan->device->privatecnt after call
dma_chan_put(). However, dma_chan_put() call dma_device_put() which could
release the last reference of the device if the DMA provider is already
gone and hence free it.
Fixes it by moving dma_chan_put() after the check. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: fix order of kfree_rcu() and rcu_assign_pointer()
Sashiko pointed out that kfree_rcu() was called before
rcu_assign_pointer() in handling the comment extension.
Fix the order so that rcu_assign_pointer() called first. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: sch_teql: Introduce slaves_lock to avoid race condition and UAF
The teql master->slaves singly linked list is not protected against
multiple writes. It can be mod'ed concurently from teql_master_xmit(),
teql_dequeue(), teql_init() and teql_destroy() without holding any list
lock or RCU protection.
zdi-disclosures@trendmicro.com has demonstrated that the qdisc is freed
after an RCU grace period, but teql_master_xmit() running on another
CPU can still hold a stale pointer into the list, resulting in a
slab-use-after-free:
BUG: KASAN: slab-use-after-free in teql_master_xmit+0xf0f/0x16b0
Read of size 8 at addr ffff888013fb0440 by task poc/332
Freed 512-byte region [ffff888013fb0400, ffff888013fb0600) (kmalloc-512)
The fix?
Add a per-master slaves_lock spinlock that serializes all mutations of
master->slaves and the NEXT_SLAVE() links in teql_destroy() and
teql_qdisc_init(). teql_master_xmit() also takes the same slaves_lock
around those updates.
Annotate master->slaves and the per-slave ->next pointer with __rcu and
use the appropriate RCU accessors everywhere they are touched:
rcu_assign_pointer() on the writer side (under slaves_lock),
rcu_dereference_protected() for the writer-side loads (also under
slaves_lock), rcu_dereference_bh() for the loads in teql_master_xmit() and
rtnl_dereference() for the loads in teql_master_open()/teql_master_mtu(),
which run under RTNL.
Pair this with rcu_read_lock_bh()/rcu_read_unlock_bh() around the list
traversal in teql_master_xmit(), so that readers either observe a fully
linked list or are deferred until the in-flight mutation completes. The two
early-return paths in teql_master_xmit() are updated to release the RCU-bh
read-side critical section before returning, since leaving it held would
disable BH on that CPU for good. |
| In the Linux kernel, the following vulnerability has been resolved:
bridge: stp: Fix a potential use-after-free when deleting a bridge
The three STP timers are not supposed to be armed while the bridge is
administratively down. They are synchronously deactivated when the
bridge is put administratively down and the various call sites check for
'IFF_UP' before arming them.
This check is missing from br_topology_change_detection() and it is
possible to engineer a situation in which the topology change timer is
armed while the bridge is administratively down, resulting in a
use-after-free [1] when the bridge is deleted.
Fix by adding the missing check and for good measures synchronously
shutdown the three timers when the bridge is deleted.
[1]
ODEBUG: free active (active state 0) object: ffff88811662b9b0 object type: timer_list hint: br_topology_change_timer_expired (net/bridge/br_stp_timer.c:120)
WARNING: lib/debugobjects.c:629 at debug_print_object+0x1bc/0x450, CPU#9: ip/359 |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: Fix adv monitor add failure cleanup
hci_add_adv_monitor() publishes a new adv_monitor in
hdev->adv_monitors_idr before the powered MSFT setup step. The MSFT
offload add path can then fail either locally before the controller add
command completes, or in the MSFT add callback. In the current queued
management add flow, hci_cmd_sync_work() still invokes
mgmt_add_adv_patterns_monitor_complete() with the original pending command
after msft_add_monitor_pattern() returns.
The buggy scenario involves two paths, with each column showing the order
within that path:
MSFT add handling MGMT completion
1. insert monitor and handle 1. receive sync error
2. send MSFT add command 2. call add-monitor completion
3. callback sees bad response 3. load cmd->user_data
4. callback frees monitor 4. read monitor->handle
Local MSFT setup failures have the other half of the same ownership bug:
they return an error after the IDR insertion, but no later code removes the
failed monitor from the IDR.
Keep ownership with the pending management command until its completion.
For normal management adds, the MSFT add callback now records successful
controller state and returns errors to its caller. The management
completion frees the monitor on non-success after copying the response
handle, while resume/reregister callback-error cleanup remains in the
MSFT callback. The success path keeps the existing bookkeeping.
Validation reproduced this kernel report:
BUG: KASAN: slab-use-after-free in mgmt_add_adv_patterns_monitor_complete+0xfb/0x260 [bluetooth]
Call Trace:
<TASK>
dump_stack_lvl+0x66/0xa0
print_report+0xce/0x5f0
? mgmt_add_adv_patterns_monitor_complete+0xfb/0x260 [bluetooth]
? srso_alias_return_thunk+0x5/0xfbef5
? __virt_addr_valid+0x19f/0x330
? mgmt_add_adv_patterns_monitor_complete+0xfb/0x260 [bluetooth]
kasan_report+0xe0/0x110
? mgmt_add_adv_patterns_monitor_complete+0xfb/0x260 [bluetooth]
mgmt_add_adv_patterns_monitor_complete+0xfb/0x260 [bluetooth]
? srso_alias_return_thunk+0x5/0xfbef5
? 0xffffffffc00d00da
? __pfx_mgmt_add_adv_patterns_monitor_complete+0x10/0x10 [bluetooth]
? __pfx_mgmt_add_adv_patterns_monitor_complete+0x10/0x10 [bluetooth]
? hci_cmd_sync_work+0x1ab/0x210 [bluetooth]
hci_cmd_sync_work+0x1c0/0x210 [bluetooth]
? __pfx_mgmt_add_adv_patterns_monitor_complete+0x10/0x10 [bluetooth]
process_one_work+0x4fd/0xbc0
? __pfx_process_one_work+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? srso_alias_return_thunk+0x5/0xfbef5
? __list_add_valid_or_report+0x37/0xf0
? __pfx_hci_cmd_sync_work+0x10/0x10 [bluetooth]
? srso_alias_return_thunk+0x5/0xfbef5
worker_thread+0x2d8/0x570
? __pfx_worker_thread+0x10/0x10
kthread+0x1ad/0x1f0
? __pfx_kthread+0x10/0x10
ret_from_fork+0x3c9/0x540
? __pfx_ret_from_fork+0x10/0x10
? srso_alias_return_thunk+0x5/0xfbef5
? __switch_to+0x2e9/0x730
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
Allocated by task 471 on cpu 3 at 285.205389s:
kasan_save_stack+0x33/0x60
kasan_save_track+0x17/0x60
__kasan_kmalloc+0xaa/0xb0
add_adv_patterns_monitor_rssi+0xd5/0x230 [bluetooth]
hci_sock_sendmsg+0x96b/0xf80 [bluetooth]
__sys_sendto+0x2bc/0x2d0
__x64_sys_sendto+0x76/0x90
do_syscall_64+0x115/0x6a0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 454 on cpu 2 at 285.217112s:
kasan_save_stack+0x33/0x60
kasan_save_track+0x17/0x60
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x5f/0x80
kfree+0x313/0x590
msft_add_monitor_sync+0x54a/0x570 [bluetooth]
hci_add_adv_monitor+0x133/0x180 [bluetooth]
hci_cmd_sync_work+0x187/0x210 [bluetooth]
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:
ipv4: igmp: Fix potential UAF in igmp_gq_start_timer()
A race condition exists between device teardown (inetdev_destroy) and
incoming IGMP query processing (igmp_rcv), leading to a Use-After-Free
in the IGMP timer callback.
During device destruction, inetdev_destroy() drops the primary reference
to in_device, which can drop its refcount to 0. The actual freeing of
in_device memory is deferred via RCU (using call_rcu()).
Concurrently, igmp_rcv() runs under RCU read lock and obtains the
in_device pointer. Because the memory is RCU-protected, CPU-0 can safely
dereference in_device even if its refcount has hit 0.
However, if CPU-0 calls igmp_gq_start_timer() and re-arms the timer, it
attempts to acquire a reference using in_dev_hold(). This increments the
refcount from 0 to 1, triggering a "refcount_t: addition on 0" warning.
Since the in_device memory is still scheduled to be freed after the RCU
grace period (as the free callback does not check the refcount again),
the device is freed while the timer is still armed. When the timer
expires, it accesses the freed memory, causing a kernel panic.
Fix this by using refcount_inc_not_zero() (via a new helper
in_dev_hold_safe()) to prevent acquiring a reference if the device is
already being destroyed. If the refcount is 0, we do not arm the timer.
A similar issue in IPv6 MLD is fixed in a subsequent patch. |
| In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: pin upper rpc_clnt across the TLS connect_worker
The TLS connect path has a use-after-free: nothing pins the
upper rpc_clnt across the delayed connect_worker. xs_connect()
stores task->tk_client in sock_xprt::clnt as a raw pointer
and queues the worker; for TLS-secured transports that worker
is xs_tcp_tls_setup_socket(), which reads several fields out
of the saved pointer (cl_timeout, cl_program, cl_prog,
cl_vers, cl_cred, cl_stats) to construct the args for the
inner handshake rpc_clnt.
The xprt does not reference the rpc_clnt; the rpc_clnt
references the xprt. xs_destroy() does cancel the
connect_worker, but it runs only when the xprt's refcount
drops to zero, which cannot happen until the rpc_clnt
releases its cl_xprt reference in rpc_free_client_work().
When a TLS handshake fails fatally (for example, an mTLS
mount whose client cert does not match the server), the
connecting task is woken with -EACCES and exits, the mount
caller invokes rpc_shutdown_client(), and the upper rpc_clnt
is freed before the queued connect_worker fires.
xs_tcp_tls_setup_socket() then dereferences the freed clnt,
producing the refcount_t underflow Michael Nemanov reported.
Take a reference on the upper rpc_clnt in xs_connect() for
TLS transports via a new rpc_hold_client() helper, and drop
it in the connect_worker's exit path with rpc_release_client().
The xprt_lock_connect() / xprt_unlock_connect() pairing
already serialises xs_connect() with xs_tcp_tls_setup_socket(),
so the take and release are balanced one-for-one.
The non-TLS connect worker (xs_tcp_setup_socket) never reads
sock_xprt::clnt, so leave that path alone and avoid the
clnt-holds-xprt-holds-clnt cycle that would otherwise prevent
xprt destruction. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: restrict socket queue dumps in enqueue tracepoints
tipc_sk_enqueue() runs with sk->sk_lock.slock held while the socket is
owned by user context. The spinlock protects the backlog queue in this
path, but it does not serialize against the socket owner consuming or
purging sk_receive_queue.
KASAN reported:
CPU: 14 UID: 0 PID: 1050 Comm: tipc3 Not tainted 7.1.0-rc6+ #126 PREEMPT(lazy)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x76/0xa0 lib/dump_stack.c:123
print_report+0xce/0x5b0 mm/kasan/report.c:482
kasan_report+0xc6/0x100 mm/kasan/report.c:597
__asan_report_load4_noabort+0x14/0x30 mm/kasan/report_generic.c:380
tipc_skb_dump+0x1327/0x16f0 net/tipc/trace.c:73
tipc_list_dump+0x208/0x2e0 net/tipc/trace.c:187
tipc_sk_dump+0xaf6/0xd60 net/tipc/socket.c:3996
trace_event_raw_event_tipc_sk_class+0x312/0x5a0 net/tipc/trace.h:188
tipc_sk_rcv+0xb1d/0x1d50 net/tipc/socket.c:2497
tipc_node_xmit+0x1c3/0x1440 net/tipc/node.c:1689
__tipc_sendmsg+0x97a/0x1440 net/tipc/socket.c:1512
tipc_sendmsg+0x52/0x80 net/tipc/socket.c:1400
sock_sendmsg+0x2f6/0x3e0 net/socket.c:825
splice_to_socket+0x7f9/0x1010 fs/splice.c:884
do_splice+0xe21/0x2330 fs/splice.c:936
__do_splice+0x153/0x260 fs/splice.c:1431
__x64_sys_splice+0x150/0x230 fs/splice.c:1616
x64_sys_call+0xeb5/0x2790 arch/x86/entry/syscall_64.c:41
do_syscall_64+0xf3/0x620 arch/x86/entry/syscall_64.c:63
entry_SYSCALL_64_after_hwframe+0x76/0x7e arch/x86/entry/entry_64.S:130
RIP: 0033:0x71624e8aafe2
Code: 08 0f 85 71 3a ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 66 2e 0f 1f 84 00 00 00 00 00 66
RSP: 002b:0000716157ffed68 EFLAGS: 00000246 ORIG_RAX: 0000000000000113
RAX: ffffffffffffffda RBX: 0000716157fff6c0 RCX: 000071624e8aafe2
RDX: 000000000000005f RSI: 0000000000000000 RDI: 0000000000000066
RBP: 0000716157ffed90 R08: 0000000000008000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffff00
R13: 0000000000000021 R14: 0000000000000000 R15: 00007fff89799c40
</TASK>
The TIPC_DUMP_ALL tracepoints in tipc_sk_enqueue() also dump
sk_receive_queue and can therefore dereference skbs that the socket
owner has already dequeued or freed. Restrict these dumps to
TIPC_DUMP_SK_BKLGQ, which matches the queue protected by the held
spinlock.
Keep the change limited to the enqueue path, where the unsafe queue dump
is reachable while the socket is owned by user context. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst
The br_netfilter fake rtable is embedded in struct net_bridge and is
attached to bridged packets with skb_dst_set_noref(). If such a packet is
queued to NFQUEUE, __nf_queue() upgrades that fake dst with
skb_dst_force().
At that point the queued skb can hold a real dst reference after bridge
teardown has started. The problem is not that every bridged packet needs
its own dst reference. The problem is that NFQUEUE can keep the bridge
private fake dst alive after unregister begins.
Fix this by keeping the bridge fake dst model unchanged and pinning the
bridge master device only while the packet sits in NFQUEUE. Record the
bridge device in nf_queue_entry when the queued skb carries a bridge fake
dst, take a device reference for the queue lifetime, and drop it when the
queue entry is freed.
Also make sure queued entries are reaped when that bridge device goes
down, and drop the redundant nf_bridge_info_exists() test from the fake
dst detection.
This keeps netdev_priv(br->dev) alive until verdict completion, so the
embedded fake rtable and its metrics backing storage cannot be freed out
from under dst_release(). It also avoids the constant refcount bump and
avoids using ipv4-specific dst helpers for IPv6 bridge traffic. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_nat_sip: reload possible stale data pointer
quoting sashiko:
------------------------------------------------------------------------
[..] noticed a potential memory bug and header corruption involving the
SIP NAT helper.
In net/netfilter/nf_nat_sip.c:nf_nat_sip():
if (skb_ensure_writable(skb, skb->len)) {
nf_ct_helper_log(skb, ct, "cannot mangle packet");
return NF_DROP;
}
uh = (void *)skb->data + protoff;
uh->dest = ct_sip_info->forced_dport;
if (!nf_nat_mangle_udp_packet(skb, ct, ctinfo, protoff,
0, 0, NULL, 0)) {
If a cloned or fragmented SKB is reallocated by skb_ensure_writable(), the
old data buffer is freed. However, nf_nat_sip() fails to update *dptr to
point to the new buffer.
It also appears to use nf_nat_mangle_udp_packet() on what could be a TCP
packet, which would overwrite the sequence number with a checksum update.
------------------------------------------------------------------------
nf_conntrack_sip linerizes skbs, hence no fragmented skb can be seen.
But clones are possible, so rebuild dptr.
Disable nf_nat_mangle_udp_packet() branch for TCP streams.
It doesn't look like this can ever happen, else we should have received
bug reports about this, so just check the conntrack is UDP and drop
otherwise.
The calling conntrack_sip set ->forced_dport for SIP_HDR_VIA_UDP messages,
so I don't think this is ever expected to be true for a TCP stream. |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: retrieve ethhdr after potential skb realloc on RX
pskb_may_pull() in batadv_interface_rx() could reallocate the buffer behind
the skb. Variables which were pointing to the old buffer need to be
reassigned to avoid an use-after-free.
This was done correctly for the VLAN header but missed for the ethernet
header which is later used for the TT and AP isolation handling. |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: access unicast_ttvn skb->data only after skb realloc
The pskb_may_pull() called by batadv_get_vid() could reallocate the buffer
behind the skb. Variables which were pointing to the old buffer need to be
reassigned to avoid an use-after-free.
This was done correctly for the ethernet header but missed for the
unicast_packet pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
batman-adv: bla: reacquire gw address after skb realloc
The pskb_may_pull() called by batadv_bla_is_backbone_gw() could reallocate
the buffer behind the skb. Variables which were pointing to the old buffer
need to be reassigned to avoid an use-after-free. |
| In the Linux kernel, the following vulnerability has been resolved:
sunrpc: pin svc_xprt across the asynchronous TLS handshake callback
svc_tcp_handshake() stores the raw svc_xprt pointer in
tls_handshake_args.ta_data and submits the request through
tls_server_hello_x509(). The handshake core takes only
sock_hold(req->hr_sk); nothing references the embedding struct
svc_sock that svc_tcp_handshake_done() reaches via container_of().
Two close races leave the in-flight callback writing through a freed
svc_sock. svc_sock_free() calls tls_handshake_cancel() and discards
its return value: a false return means handshake_complete() has
already set HANDSHAKE_F_REQ_COMPLETED but hp_done() may not have
finished, yet svc_sock_free() proceeds to kfree(svsk). The
cancel-loser fall-through inside svc_tcp_handshake() itself produces
the same window: when wait_for_completion_interruptible_timeout()
returns <= 0 (timeout or signal) and tls_handshake_cancel() returns
false, the function does not drain, returns, and svc_handle_xprt()
calls svc_xprt_received(), which clears XPT_BUSY and can drop the
last reference. A concurrent close then runs svc_sock_free() while
svc_tcp_handshake_done() is still updating xpt_flags and walking
svsk->sk_handshake_done.
The corruption surfaces as set_bit/clear_bit RMW into the freed
xpt_flags slab slot and as complete_all() walking and writing the
freed wait_queue_head_t list embedded in sk_handshake_done -- a
slab-corruption primitive, not a benign read. The path is reachable
on any TLS-enabled NFS server whenever a connection close overlaps
the tlshd downcall delivery window; the interruptible wait means
signal delivery suffices, not just SVC_HANDSHAKE_TO expiry.
Take svc_xprt_get(xprt) immediately before tls_server_hello_x509()
so the in-flight callback owns its own reference. Release it on the
two edges where the callback is guaranteed not to fire -- submission
failure from tls_server_hello_x509() and a successful
tls_handshake_cancel() -- and at the tail of
svc_tcp_handshake_done() after complete_all().
[cel: rewrote commit message to describe the actual change] |
| In the Linux kernel, the following vulnerability has been resolved:
can: isotp: fix use-after-free race with concurrent NETDEV_UNREGISTER
isotp_release() looked up the bound network device via dev_get_by_index()
using the stored ifindex. During device unregistration the device is
unlisted from the ifindex hash before the NETDEV_UNREGISTER notifier
chain runs, so a concurrent isotp_release() could find no device, skip
can_rx_unregister() entirely, and still proceed to free the socket.
Since isotp_release() had already removed itself from the isotp
notifier list at that point, isotp_notify() would never get a chance to
clean up either, leaving a stale CAN filter that keeps pointing at the
freed socket.
Fix this the same way raw.c already does: hold a tracked reference to
the bound net_device in the socket (so->dev/so->dev_tracker) from
bind() onward instead of re-resolving it from the ifindex, and
serialize bind()/release() with rtnl_lock() so that so->dev is always
consistent with what the NETDEV_UNREGISTER notifier sees. so->dev
stays valid regardless of ifindex-hash unlisting, and is only ever
cleared by whichever of isotp_release()/isotp_notify() gets there
first, so the filter is always removed exactly once.
isotp_bind() now rejects a (re)bind with -EAGAIN while so->[tx|rx].state
isn't ISOTP_IDLE yet, so a timer left running by a prior
NETDEV_UNREGISTER can't act on a newly bound so->ifindex. Both checks
share the same lock_sock() section, so there is no window in which a
concurrent isotp_notify() clearing so->bound could be missed. |
| In the Linux kernel, the following vulnerability has been resolved:
can: bcm: add missing device refcount for CAN filter removal
sashiko-bot remarked a problem with a concurrent device unregistration
in isotp.c which also is present in the bcm.c code. A former fix for raw.c
commit c275a176e4b6 ("can: raw: add missing refcount for memory leak fix")
introduced a netdevice_tracker which solves the issue for bcm.c too.
bcm_release(), bcm_delete_rx_op() and bcm_notifier() relied on
dev_get_by_index(ifindex) to re-find the device for an rx_op before
unregistering its filter. If a concurrent NETDEV_UNREGISTER has already
unlisted the device from the ifindex table, that lookup fails and
can_rx_unregister() is silently skipped, leaving a stale CAN filter
pointing at the soon-to-be-freed bcm_op/socket.
Hold a netdev_hold()/netdev_put() tracked reference on op->rx_reg_dev
from the moment the rx filter is registered in bcm_rx_setup() until it
is unregistered in bcm_rx_unreg(), and use that reference directly in
bcm_release() and bcm_delete_rx_op() instead of re-looking the device
up by ifindex. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf,fork: wipe ->bpf_storage before bailouts that access it
Currently, copy_process() can bail out to free_task() before p->bpf_storage
has been initialized, with this call graph (shown here for the
!CONFIG_MEMCG case):
copy_process
dup_task_struct
arch_dup_task_struct
[copies the entire task_struct, including ->bpf_storage member]
[RLIMIT_NPROC check fails]
delayed_free_task
free_task
bpf_task_storage_free
rcu_dereference(task->bpf_storage)
bpf_local_storage_destroy
In this case, the nascent task's ->bpf_storage member that
bpf_local_storage_destroy() operates on is a plain copy of the parent's
->bpf_storage pointer, not a real initialized pointer.
This leads to badness (kernel hangs, UAF).
This is reachable as long as the process calling fork() has been inserted
into a task storage map. |
| In the Linux kernel, the following vulnerability has been resolved:
6lowpan: fix NHC entry use-after-free on error path
lowpan_nhc_do_uncompression() looks up an NHC descriptor while holding
lowpan_nhc_lock. If the descriptor has no uncompress callback, the error
path drops the lock before printing nhc->name.
lowpan_nhc_del() removes descriptors under the same lock and then relies
on synchronize_net() before the owning module can be unloaded. That only
waits for net RX RCU readers. lowpan_header_decompress() is also exported
and can be reached from callers that are not necessarily covered by the net
core RX critical section, for example the Bluetooth 6LoWPAN L2CAP receive
path.
This leaves a race where one task drops lowpan_nhc_lock in the error path,
another task unregisters and frees the matching descriptor after
synchronize_net() returns, and the first task then dereferences nhc->name
for the warning.
With the post-unlock window widened, KASAN reports:
BUG: KASAN: slab-use-after-free in lowpan_nhc_do_uncompression+0x1f4/0x220
Read of size 8
lowpan_nhc_do_uncompression
lowpan_header_decompress
Fix this by printing the warning before dropping lowpan_nhc_lock, so the
descriptor name is read while unregister is still excluded. The malformed
packet is still rejected with -ENOTSUPP. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: qat - fix VF2PF work teardown race in adf_disable_sriov()
The VF2PF interrupt handler queues PF-side response work that stores a
raw pointer to per-VF state (struct adf_accel_vf_info). Currently,
adf_disable_sriov() destroys per-VF mutexes and frees vf_info without
stopping new VF2PF work or waiting for in-flight workers to complete. A
concurrently scheduled or already queued worker can then dereference
freed memory.
This manifests as a use-after-free when KASAN is enabled:
BUG: KASAN: null-ptr-deref in mutex_lock+0x76/0xe0
Write of size 8 at addr 0000000000000260 by task kworker/24:2/...
Workqueue: qat_pf2vf_resp_wq adf_iov_send_resp [intel_qat]
Call Trace:
kasan_report+0x119/0x140
mutex_lock+0x76/0xe0
adf_gen4_pfvf_send+0xd4/0x1f0 [intel_qat]
adf_recv_and_handle_vf2pf_msg+0x290/0x360 [intel_qat]
adf_iov_send_resp+0x8c/0xe0 [intel_qat]
process_one_work+0x6ac/0xfd0
worker_thread+0x4dd/0xd30
kthread+0x326/0x410
ret_from_fork+0x33b/0x670
Add a PF-local flag, vf2pf_disabled, that gates work queueing, worker
processing, and interrupt re-enabling during teardown. Set this flag
atomically with the hardware interrupt mask inside
adf_disable_all_vf2pf_interrupts(). After masking, synchronize the AE
cluster MSI-X interrupt and flush the PF response workqueue before
tearing down per-VF locks and state so all in-flight work completes
before vf_info is destroyed.
Introduce adf_enable_all_vf2pf_interrupts() to clear the flag and
unmask all VF2PF interrupts under the same lock when SR-IOV is
re-enabled. This ensures the software flag and hardware state transition
atomically on both the enable and disable paths. |
