| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| A vulnerability was identified in Linux Kernel up to 4.19.316/5.4.278/5.10.220/5.15.161. This impacts the function tcp_getsockopt/tcp_setsockopt of the component TCP Handler. Such manipulation leads to race condition. A high complexity level is associated with this attack. The exploitability is said to be difficult. The vulnerability was introduced in 2.6.12, commit 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2"). Upgrading to version 4.19.317, 5.4.279, 5.10.221, 5.15.162 and 6.1 will fix this issue. The name of the patch is fcd31dd8291b23d713245947ec2b2d99ef07aef2/3b32f265805a49071e2c4568a524398ba22bf93c/d529193eae979a7bf2255cd9fe68b7af7a1c91b3/5bb642cc3355ffd3c8bca0a8bd8e6e65bcc2091c/f49cd2f4d6170d27a2c61f1fecb03d8a70c91f57. The affected component should be upgraded. |
| In the Linux kernel, the following vulnerability has been resolved:
posix-cpu-timers: Prevent UAF caused by non-leader exec() race
Wongi and Jungwoo decoded and reported a non-leader exec() related race
which can result in an UAF:
sys_timer_delete() exec()
posix_cpu_timer_del()
// Observes old leader
p = pid_task(pid, pid_type); de_thread()
switch_leader();
release_task(old_leader)
__exit_signal(old_leader)
sighand = lock(old_leader, sighand);
posix_cpu_timers*_exit();
sighand = lock_task_sighand(p) unhash_task(old_leader);
sh = lock(p, sighand) old_leader->sighand = NULL;
unlock(sighand);
(p->sighand == NULL)
unlock(sh)
return NULL;
// Returns without action
if(!sighand)
return 0;
free_posix_timer();
This is "harmless" unless the deleted timer was armed and enqueued in
p->signal because on exec() a TGID targeted timer is inherited.
As sys_timer_delete() freed the underlying posix timer object
run_posix_cpu_timers() or any timerqueue related add/delete operations on
other timers will access the freed object's timerqueue node, which results
in an UAF.
There is a similar problem vs. posix_cpu_timer_set(). For regular posix
timers it just transiently returns -ESRCH to user space, but for the use
case in do_cpu_nanosleep() it's the same UAF just that the k_itimer is
allocated on the stack.
Also posix_cpu_timer_rearm() fails to rearm the timer, which means it stops
to expire.
While debating solutions Frederic pointed out another problem:
posix_cpu_timer_del(tmr)
__exit_signal(p)
posix_cpu_timers*_exit(p);
unhash_task(p);
p->sighand = NULL;
sh = lock_task_sighand(p)
sighand = p->sighand;
if (!sighand)
return NULL;
lock(sighand);
if (!sh)
WARN_ON_ONCE(timer_queued(tmr));
On weakly ordered architectures it is not guaranteed that
posix_cpu_timer_del() will observe the stores in posix_cpu_timers*_exit()
when p->sighand is observed as NULL, which means the WARN() can be a false
positive.
Solve these issues by:
1) Changing the store in __exit_signal() to smp_store_release().
2) Adding a smp_acquire__after_ctrl_dep() into the !sighand path
of lock_task_sighand().
3) Creating a helper function for looking up the task and locking sighand
which does not return when sighand == NULL. Instead it retries the
task lookup and only if that fails it gives up.
4) Using that helper in the three affected functions.
#1/#2 ensures that the reader side which observes sighand == NULL also
observes all preceeding stores, i.e. the stores in posix_cpu_timers*_exit()
and the ones in unhash_task().
#3 ensures that the above described non-leader exec() situation is handled
gracefully. When the task lookup returns the old leader, but sighand ==
NULL then it retries. In the non-leader exec() case the subsequent task
lookup will observe the new leader due to #1/#2. In normal exit() scenarios
the subsequent lookup fails.
When the task lookup fails, the function also checks whether the timer is
still enqueued and issues a warning if that's the case. Unfortunately there
is nothing which can be done about it, but as the task is already not
longer visible the timer should not be accessed anymore. This check also
requires memory ordering, which is not provided when the first lookup
fails. To achieve that the check is preceeded by a smp_rmb() which pairs
with the smp_wmb() in write_seqlock() in __exit_signal(). That ensures that
the stores in posix_cpu_timers*_exit() are visible.
The history of the non-leader exec() issue goes back to the early days of
posix CPU timers, which stored a pointer to the group leader task in the
timer. That obviously fails when a non-leader exec() switches the leader.
commit e0a70217107e ("posix-cpu-timers: workaround to suppress the problems
with mt exec") added a temporary workaround for that in 2010 which surv
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
s390/pkey: Check length in PKEY_VERIFYPROTK ioctl
Explicitly check the buffer length request structure provided by
user-space and fail, if it exceeds the buffer size. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/pkey: Check length in pkey_pckmo handler implementation
Explicitly check the length of the target buffer in the pkey_pckmo
implementation of the key_to_protkey() handler function. The handler
function fails, if the generated output data exceeds the length of the
provided target buffer. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()
l2cap_sock_new_connection_cb() returned l2cap_pi(sk)->chan after
release_sock(parent). Once the parent lock is dropped the newly
enqueued child socket sk is reachable via the accept queue, so another
task can accept and free it before the callback dereferences sk,
resulting in a use-after-free.
Rework the ->new_connection() op so the core, rather than the callback,
owns the child channel's lifetime. The op now receives a pre-allocated
new_chan and returns an errno instead of allocating and returning a
channel. l2cap_new_connection() allocates the child channel and links
it into the conn list via __l2cap_chan_add() before invoking the
callback, so the conn-list reference keeps the channel alive once
release_sock(parent) exposes the socket to other tasks.
Channel configuration that was duplicated in l2cap_sock_init() and the
various new_connection callbacks is consolidated into
l2cap_chan_set_defaults(), which now inherits from the parent channel
when one is supplied. |
| In the Linux kernel, the following vulnerability has been resolved:
perf/core: Detach event groups during remove_on_exec
perf_event_remove_on_exec() removes events by calling
perf_event_exit_event(). For top-level events, this removes the event from
the context with DETACH_EXIT only.
This can leave inconsistent group state when a removed event is a group
leader and the group contains siblings without remove_on_exec. If the group
was active, the surviving siblings can remain active and attached to the
removed leader's sibling list, but are no longer represented by a valid
group leader on the PMU context active lists.
A later close of the removed leader uses DETACH_GROUP and can promote the
still-active siblings from this stale group state. The next schedule-in can
then add an already-linked active_list entry again, corrupting the PMU
context active list.
With DEBUG_LIST enabled, this is caught as a list_add double-add in
merge_sched_in().
Fix this by detaching group relationships when remove_on_exec removes an
event. This preserves the existing task-exit and revoke behavior, while
ensuring surviving siblings are ungrouped before the removed event leaves
the context. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: arm64: nv: Fix SPSR_EL2 restore in kvm_hyp_handle_mops()
kvm_hyp_handle_mops() resets the single-step state machine as part of
rewinding state for a MOPS exception by modifying vcpu_cpsr() and
writing the result directly into hardware.
In the case of nested virtualization, vcpu_cpsr() is a synthetic value
such that the rest of KVM can deal with vEL2 cleanly. That means the
value requires translation before being written into hardware, which is
unfortunately missing from the MOPS handler.
Fix it by directly modifying SPSR_EL2 and avoiding the synthetic state
altogether, which will be resynchronized on the next 'full' exit back
to KVM. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: bridge: fix stale prevhdr pointer in br_ip6_fragment()
br_ip6_fragment() gets prevhdr, a pointer into the skb head, from
ip6_find_1stfragopt(), then calls skb_checksum_help(). For a cloned skb
skb_checksum_help() reallocates the head via pskb_expand_head(), leaving
prevhdr dangling. It is later dereferenced in ip6_frag_next(), causing a
use-after-free write.
Save prevhdr's offset before skb_checksum_help() and recompute it after,
like commit ef0efcd3bd3f ("ipv6: Fix dangling pointer when ipv6
fragment").
BUG: KASAN: slab-use-after-free in ip6_frag_next (net/ipv6/ip6_output.c:857)
Write of size 1 at addr ffff888013ff5016 by task exploit/141
Call Trace:
...
kasan_report (mm/kasan/report.c:595)
ip6_frag_next (net/ipv6/ip6_output.c:857)
br_ip6_fragment (net/ipv6/netfilter.c:212)
nf_ct_bridge_post (net/bridge/netfilter/nf_conntrack_bridge.c:407)
nf_hook_slow (net/netfilter/core.c:619)
br_forward_finish (net/bridge/br_forward.c:66)
__br_forward (net/bridge/br_forward.c:115)
maybe_deliver (net/bridge/br_forward.c:191)
br_flood (net/bridge/br_forward.c:245)
br_handle_frame_finish (net/bridge/br_input.c:229)
br_handle_frame (net/bridge/br_input.c:442)
...
packet_sendmsg (net/packet/af_packet.c:3114)
...
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Kernel panic - not syncing: Fatal exception in interrupt |
| In the Linux kernel, the following vulnerability has been resolved:
virtio-net: fix len check in receive_big()
receive_big() bounds the device-announced length by
(big_packets_num_skbfrags + 1) * PAGE_SIZE. That is still too loose:
add_recvbuf_big() sets sg[1] to start at offset
sizeof(struct padded_vnet_hdr) into the first page, so the chain
actually carries hdr_len + (PAGE_SIZE - sizeof(padded_vnet_hdr)) +
big_packets_num_skbfrags * PAGE_SIZE bytes -- 20 bytes less than the
check allows for the common hdr_len == 12 case.
A malicious virtio backend can announce a len in that gap. page_to_skb()
then walks one frag past the page chain, storing a NULL page->private
into skb_shinfo()->frags[MAX_SKB_FRAGS], which is both an out-of-bounds
write past the static frag array and a NULL frag handed up the rx path.
Bound len by the size add_recvbuf_big() actually advertised. |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: validate STALE_COOKIE cause length before reading staleness
When an ERROR chunk with a STALE_COOKIE cause is received in the
COOKIE_ECHOED state, sctp_sf_do_5_2_6_stale() reads the 4-byte Measure
of Staleness that follows the cause header:
err = (struct sctp_errhdr *)(chunk->skb->data);
stale = ntohl(*(__be32 *)((u8 *)err + sizeof(*err)));
err is the first cause in the chunk, not the STALE_COOKIE cause that
caused the dispatch, and nothing guarantees the staleness field is
present. sctp_walk_errors() only requires a cause to be as long as the
4-byte header, so for a STALE_COOKIE cause of length 4 the read runs
past the cause, and for a minimal ERROR chunk past skb->tail. The value
is echoed to the peer in the Cookie Preservative of the reply INIT,
leaking uninitialized memory.
sctp_sf_cookie_echoed_err() already walks to the STALE_COOKIE cause, so
check its length there and pass it to sctp_sf_do_5_2_6_stale(), which
reads that cause instead of the first one. A STALE_COOKIE cause too
short to hold the staleness field is discarded.
The read is reachable by any peer that can drive an association into
COOKIE_ECHOED, including an unprivileged process using a raw SCTP socket
in a user and network namespace. |
| In the Linux kernel, the following vulnerability has been resolved:
net: qualcomm: rmnet: validate MAP frame length before ingress parsing
When ingress deaggregation is disabled, rmnet_map_ingress_handler() passes
the skb straight to __rmnet_map_ingress_handler(), skipping the length
validation that rmnet_map_deaggregate() performs on the aggregated path.
The parser then dereferences the MAP header and csum header/trailer based on
the on-wire pkt_len without checking skb->len, so a short frame is read out
of bounds:
BUG: KASAN: slab-out-of-bounds in rmnet_map_checksum_downlink_packet
Read of size 1 at addr ffff88801118ed00 by task exploit/147
Call Trace:
...
rmnet_map_checksum_downlink_packet (drivers/net/ethernet/qualcomm/rmnet/rmnet_map_data.c:413)
__rmnet_map_ingress_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:96)
rmnet_rx_handler (drivers/net/ethernet/qualcomm/rmnet/rmnet_handlers.c:129)
__netif_receive_skb_core.constprop.0 (net/core/dev.c:6089)
netif_receive_skb (net/core/dev.c:6460)
tun_get_user (drivers/net/tun.c:1955)
tun_chr_write_iter (drivers/net/tun.c:2001)
vfs_write (fs/read_write.c:688)
ksys_write (fs/read_write.c:740)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
...
Factor that validation out of rmnet_map_deaggregate() into
rmnet_map_validate_packet_len() and run it on the no-aggregation path too.
The MAP header is bounds-checked first, since this path can receive a frame
shorter than the header. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: reject overflowing copy + len in bpf_msg_push_data()
When the scatterlist ring is full or nearly full, bpf_msg_push_data()
enters a copy fallback path and computes copy + len for the page
allocation size. Since len comes from BPF with arg3_type = ARG_ANYTHING
and both are u32, a crafted len can wrap the sum to a small value,
causing an undersized allocation followed by an out-of-bounds memcpy.
BUG: unable to handle page fault for address: ffffed104089a402
Oops: Oops: 0000 [#1] SMP KASAN NOPTI
Call Trace:
__asan_memcpy (mm/kasan/shadow.c:105)
bpf_msg_push_data (net/core/filter.c:2852 net/core/filter.c:2788)
bpf_prog_9ed8b5711920a7d7+0x2e/0x36
sk_psock_msg_verdict (net/core/skmsg.c:934)
tcp_bpf_sendmsg (net/ipv4/tcp_bpf.c:421 net/ipv4/tcp_bpf.c:584)
__sys_sendto (net/socket.c:2206)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
Add an overflow check before the allocation. |
| In the Linux kernel, the following vulnerability has been resolved:
net: usb: net1080: validate packet_len before pad-byte access in rx_fixup
For an even packet_len, net1080_rx_fixup() reads the pad byte at
skb->data[packet_len] before the skb->len != packet_len check further
down, and packet_len is only bounded against NC_MAX_PACKET. A malicious
NetChip 1080 device can send a short frame advertising a large even
packet_len (e.g. 0x4000), so the pad-byte read lands past the end of the
skb:
BUG: KASAN: slab-out-of-bounds in net1080_rx_fixup
Read of size 1 at addr ffff8880106c83c6 by task ksoftirqd/0/14
...
net1080_rx_fixup (drivers/net/usb/net1080.c:384)
usbnet_bh (drivers/net/usb/usbnet.c:1589)
process_one_work (kernel/workqueue.c:3322)
bh_worker (kernel/workqueue.c:3708)
tasklet_action (kernel/softirq.c:965)
handle_softirqs (kernel/softirq.c:622)
...
Reject the frame when packet_len >= skb->len before reading. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/edid: fix OOB read in drm_parse_tiled_block()
drm_parse_tiled_block() casts the DisplayID block to a
struct displayid_tiled_block and reads the full fixed layout up to
tile->topology_id[7] without checking block->num_bytes. The DisplayID
iterator only validates the declared payload length, so a crafted EDID
can advertise a tiled-display block (tag DATA_BLOCK_TILED_DISPLAY, or
DATA_BLOCK_2_TILED_DISPLAY_TOPOLOGY for v2.0) with a small num_bytes at
the end of a DisplayID extension. The read then runs past the end of the
exact-sized kmemdup()'d EDID allocation, a heap out-of-bounds read.
Reject blocks shorter than the spec's 22-byte tiled payload before
reading the fixed struct, as drm_parse_vesa_mso_data() already does.
BUG: KASAN: slab-out-of-bounds in drm_edid_connector_update
Read of size 2 at addr ffff888010077700 by task exploit/147
dump_stack_lvl (lib/dump_stack.c:94 ...)
print_report (mm/kasan/report.c:378 ...)
kasan_report (mm/kasan/report.c:595)
drm_edid_connector_update (drivers/gpu/drm/drm_edid.c:7581)
bochs_connector_helper_get_modes (drivers/gpu/drm/tiny/bochs.c:574)
drm_helper_probe_single_connector_modes (drivers/gpu/drm/drm_probe_helper.c:426)
status_store (drivers/gpu/drm/drm_sysfs.c:219)
...
vfs_write (fs/read_write.c:595 fs/read_write.c:688)
ksys_write (fs/read_write.c:740) |
| In the Linux kernel, the following vulnerability has been resolved:
net, bpf: check master for NULL in xdp_master_redirect()
xdp_master_redirect() dereferences the result of
netdev_master_upper_dev_get_rcu() without a NULL check, but that helper
returns NULL when the receiving device has no upper-master adjacency.
The reach guard only checks netif_is_bond_slave(). On bond slave release
bond_upper_dev_unlink() drops the upper-master adjacency before clearing
IFF_SLAVE, so an XDP_TX reaching xdp_master_redirect() in that window
still passes netif_is_bond_slave() while master is already NULL, and
faults on master->flags at offset 0xb0:
BUG: kernel NULL pointer dereference, address: 00000000000000b0
RIP: 0010:xdp_master_redirect (net/core/filter.c:4432)
Call Trace:
xdp_master_redirect (net/core/filter.c:4432)
bpf_prog_run_generic_xdp (include/net/xdp.h:700)
do_xdp_generic (net/core/dev.c:5608)
__netif_receive_skb_one_core (net/core/dev.c:6204)
process_backlog (net/core/dev.c:6319)
__napi_poll (net/core/dev.c:7729)
net_rx_action (net/core/dev.c:7792)
handle_softirqs (kernel/softirq.c:622)
__dev_queue_xmit (include/linux/bottom_half.h:33)
packet_sendmsg (net/packet/af_packet.c:3082)
__sys_sendto (net/socket.c:2252)
Kernel panic - not syncing: Fatal exception in interrupt
The missing check dates back to the original code; commit 1921f91298d1
("net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master")
later added the master->flags read where the fault now lands but kept the
unconditional deref. Check master for NULL before use; a NULL master is
treated the same as one that is not up. |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix use-after-free of the discoverer in tipc_disc_rcv()
bearer_disable() frees b->disc with tipc_disc_delete()'s plain kfree(),
but tipc_disc_rcv() still dereferences b->disc in RX softirq under
rcu_read_lock() (tipc_udp_recv -> tipc_rcv -> tipc_disc_rcv).
L2 bearers are safe thanks to the synchronize_net() in
tipc_disable_l2_media(), but the UDP bearer defers that call to the
cleanup_bearer() workqueue, so the discoverer is freed with no grace
period:
BUG: KASAN: slab-use-after-free in tipc_disc_rcv (net/tipc/discover.c:149)
Read of size 8 at addr ffff88802348b728 by task poc_tipc/184
<IRQ>
tipc_disc_rcv (net/tipc/discover.c:149)
tipc_rcv (net/tipc/node.c:2126)
tipc_udp_recv (net/tipc/udp_media.c:391)
udp_rcv (net/ipv4/udp.c:2643)
ip_local_deliver_finish (net/ipv4/ip_input.c:241)
</IRQ>
Freed by task 181:
kfree (mm/slub.c:6565)
bearer_disable (net/tipc/bearer.c:418)
tipc_nl_bearer_disable (net/tipc/bearer.c:1001)
The bearer is freed with kfree_rcu(); free the discoverer the same way.
Add an rcu_head to struct tipc_discoverer and free it and its skb from an
RCU callback.
Because the RCU callback (tipc_disc_free_rcu) lives in module text, a
call_rcu() that is still pending when the tipc module is unloaded would
invoke a freed function. Add an rcu_barrier() to tipc_exit() after the
bearer subsystem has been torn down, so all pending discoverer callbacks
have run before the module text goes away.
Reachable from an unprivileged user namespace: the TIPCv2 genl family is
netnsok and its bearer commands have no GENL_ADMIN_PERM. Needs CONFIG_TIPC
and CONFIG_TIPC_MEDIA_UDP. |
| 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:
usbnet: gl620a: fix out-of-bounds read in genelink_rx_fixup()
genelink_rx_fixup() splits an aggregated RX frame into its individual
packets, using a per-packet length taken from device-supplied data. That
length is only bounded by GL_MAX_PACKET_LEN (1514); it is never compared
against how many bytes were actually received.
A malicious GeneLink (GL620A) device can therefore send a short URB whose
header claims packet_count > 1 and a first packet of up to 1514 bytes.
skb_put_data(gl_skb, packet->packet_data, size);
then copies past the end of the receive buffer and hands the adjacent slab
contents up the network stack, an out-of-bounds read that leaks kernel heap.
No privilege is required: the path runs in the usbnet RX softirq as soon as
the interface is up.
BUG: KASAN: slab-out-of-bounds in genelink_rx_fixup (drivers/net/usb/gl620a.c:112)
Read of size 1514 at addr ffff888011309708 by task ksoftirqd/0/14
Call Trace:
...
__asan_memcpy (mm/kasan/shadow.c:105)
genelink_rx_fixup (include/linux/skbuff.h:2814 drivers/net/usb/gl620a.c:112)
usbnet_bh (drivers/net/usb/usbnet.c:572 drivers/net/usb/usbnet.c:1589)
process_one_work (kernel/workqueue.c:3322)
bh_worker (kernel/workqueue.c:3405)
tasklet_action (kernel/softirq.c:965)
handle_softirqs (kernel/softirq.c:622)
run_ksoftirqd (kernel/softirq.c:1076)
...
skb_pull() already verifies that the requested length fits the buffer and
returns NULL otherwise. Move it ahead of the copy and check its result, so
a packet that overruns the received data is rejected before it is read.
Well-formed frames, whose packets are fully present, are unaffected. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: eir: Fix stack OOB write when prepending the Flags AD
eir_create_adv_data() builds the advertising data into a fixed-size
buffer ("size", 31 for the legacy path). It may prepend a 3-byte "Flags"
AD structure (LE_AD_NO_BREDR on an LE-only controller) and then copies
the per-instance data without checking that it still fits:
memcpy(ptr, adv->adv_data, adv->adv_data_len);
tlv_data_max_len() only reserves those 3 bytes when the user-supplied
flags carry a managed-flags bit, so an instance added with flags == 0 is
accepted with adv_data_len up to the full buffer. At advertise time the
flags are still prepended, and the memcpy() writes 3 + adv_data_len
bytes into the size-byte buffer:
BUG: KASAN: stack-out-of-bounds in eir_create_adv_data (net/bluetooth/eir.c:301)
Write of size 31 at addr ffff88800a547bdc by task kworker/u9:0/65
Workqueue: hci0 hci_cmd_sync_work
__asan_memcpy (mm/kasan/shadow.c:106)
eir_create_adv_data (net/bluetooth/eir.c:301)
hci_update_adv_data_sync (net/bluetooth/hci_sync.c:1310)
hci_schedule_adv_instance_sync (net/bluetooth/hci_sync.c:1817)
hci_cmd_sync_work (net/bluetooth/hci_sync.c:332)
This frame has 1 object:
[32, 64) 'cp'
The "Flags" structure is added by the kernel, not requested by
userspace, so only prepend it when it fits together with the instance
advertising data; when there is no room for both, drop the flags rather
than the user-provided data.
Reachable by a local user with CAP_NET_ADMIN owning an LE-only
controller on the legacy advertising path. |
| In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix OOB reads in is_ap_in_tkip() IE loop
The loop in is_ap_in_tkip() iterates over IEs without verifying that
enough bytes remain before dereferencing the IE header or its payload:
- pIE->element_id and pIE->length are read without checking that
i + sizeof(*pIE) <= ie_length, so a truncated IE at the end of the
buffer causes an OOB read.
- For WLAN_EID_VENDOR_SPECIFIC the code compares pIE->data + 12,
which requires pIE->length >= 16. For WLAN_EID_RSN it compares
pIE->data + 8, requiring pIE->length >= 12. Neither requirement
is checked.
Add the missing IE header and payload bounds checks and guard each
data access with an explicit pIE->length minimum, matching the
pattern established in update_beacon_info(). |