| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: TAS2781: Fix tasdev_load_calibrated_data()
This function has a reversed if statement so it's either a no-op or it
leads to a NULL dereference. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: Check socket flag instead of hcon
This fixes the following Smatch static checker warning:
net/bluetooth/iso.c:1364 iso_sock_recvmsg()
error: we previously assumed 'pi->conn->hcon' could be null (line 1359)
net/bluetooth/iso.c
1347 static int iso_sock_recvmsg(struct socket *sock, struct msghdr *msg,
1348 size_t len, int flags)
1349 {
1350 struct sock *sk = sock->sk;
1351 struct iso_pinfo *pi = iso_pi(sk);
1352
1353 BT_DBG("sk %p", sk);
1354
1355 if (test_and_clear_bit(BT_SK_DEFER_SETUP,
&bt_sk(sk)->flags)) {
1356 lock_sock(sk);
1357 switch (sk->sk_state) {
1358 case BT_CONNECT2:
1359 if (pi->conn->hcon &&
^^^^^^^^^^^^^^ If ->hcon is NULL
1360 test_bit(HCI_CONN_PA_SYNC,
&pi->conn->hcon->flags)) {
1361 iso_conn_big_sync(sk);
1362 sk->sk_state = BT_LISTEN;
1363 } else {
--> 1364 iso_conn_defer_accept(pi->conn->hcon);
^^^^^^^^^^^^^^
then we're toast
1365 sk->sk_state = BT_CONFIG;
1366 }
1367 release_sock(sk);
1368 return 0;
1369 case BT_CONNECTED:
1370 if (test_bit(BT_SK_PA_SYNC, |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Ignore too large handle values in BIG
hci_le_big_sync_established_evt is necessary to filter out cases where the
handle value is belonging to ida id range, otherwise ida will be erroneously
released in hci_conn_cleanup. |
| In the Linux kernel, the following vulnerability has been resolved:
bluetooth/hci: disallow setting handle bigger than HCI_CONN_HANDLE_MAX
Syzbot hit warning in hci_conn_del() caused by freeing handle that was
not allocated using ida allocator.
This is caused by handle bigger than HCI_CONN_HANDLE_MAX passed by
hci_le_big_sync_established_evt(), which makes code think it's unset
connection.
Add same check for handle upper bound as in hci_conn_set_handle() to
prevent warning. |
| In the Linux kernel, the following vulnerability has been resolved:
md/raid5: fix deadlock that raid5d() wait for itself to clear MD_SB_CHANGE_PENDING
Xiao reported that lvm2 test lvconvert-raid-takeover.sh can hang with
small possibility, the root cause is exactly the same as commit
bed9e27baf52 ("Revert "md/raid5: Wait for MD_SB_CHANGE_PENDING in raid5d"")
However, Dan reported another hang after that, and junxiao investigated
the problem and found out that this is caused by plugged bio can't issue
from raid5d().
Current implementation in raid5d() has a weird dependence:
1) md_check_recovery() from raid5d() must hold 'reconfig_mutex' to clear
MD_SB_CHANGE_PENDING;
2) raid5d() handles IO in a deadloop, until all IO are issued;
3) IO from raid5d() must wait for MD_SB_CHANGE_PENDING to be cleared;
This behaviour is introduce before v2.6, and for consequence, if other
context hold 'reconfig_mutex', and md_check_recovery() can't update
super_block, then raid5d() will waste one cpu 100% by the deadloop, until
'reconfig_mutex' is released.
Refer to the implementation from raid1 and raid10, fix this problem by
skipping issue IO if MD_SB_CHANGE_PENDING is still set after
md_check_recovery(), daemon thread will be woken up when 'reconfig_mutex'
is released. Meanwhile, the hang problem will be fixed as well. |
| In the Linux kernel, the following vulnerability has been resolved:
ext4: fix mb_cache_entry's e_refcnt leak in ext4_xattr_block_cache_find()
Syzbot reports a warning as follows:
============================================
WARNING: CPU: 0 PID: 5075 at fs/mbcache.c:419 mb_cache_destroy+0x224/0x290
Modules linked in:
CPU: 0 PID: 5075 Comm: syz-executor199 Not tainted 6.9.0-rc6-gb947cc5bf6d7
RIP: 0010:mb_cache_destroy+0x224/0x290 fs/mbcache.c:419
Call Trace:
<TASK>
ext4_put_super+0x6d4/0xcd0 fs/ext4/super.c:1375
generic_shutdown_super+0x136/0x2d0 fs/super.c:641
kill_block_super+0x44/0x90 fs/super.c:1675
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7327
[...]
============================================
This is because when finding an entry in ext4_xattr_block_cache_find(), if
ext4_sb_bread() returns -ENOMEM, the ce's e_refcnt, which has already grown
in the __entry_find(), won't be put away, and eventually trigger the above
issue in mb_cache_destroy() due to reference count leakage.
So call mb_cache_entry_put() on the -ENOMEM error branch as a quick fix. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: pcie: handle randbuf allocation failure
The kzalloc() in brcmf_pcie_download_fw_nvram() will return null
if the physical memory has run out. As a result, if we use
get_random_bytes() to generate random bytes in the randbuf, the
null pointer dereference bug will happen.
In order to prevent allocation failure, this patch adds a separate
function using buffer on kernel stack to generate random bytes in
the randbuf, which could prevent the kernel stack from overflow. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Add a timeout to acquire the command queue semaphore
Prevent forced completion handling on an entry that has not yet been
assigned an index, causing an out of bounds access on idx = -22.
Instead of waiting indefinitely for the sem, blocking flow now waits for
index to be allocated or a sem acquisition timeout before beginning the
timer for FW completion.
Kernel log example:
mlx5_core 0000:06:00.0: wait_func_handle_exec_timeout:1128:(pid 185911): cmd[-22]: CREATE_UCTX(0xa04) No done completion |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5: Discard command completions in internal error
Fix use after free when FW completion arrives while device is in
internal error state. Avoid calling completion handler in this case,
since the device will flush the command interface and trigger all
completions manually.
Kernel log:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
...
RIP: 0010:refcount_warn_saturate+0xd8/0xe0
...
Call Trace:
<IRQ>
? __warn+0x79/0x120
? refcount_warn_saturate+0xd8/0xe0
? report_bug+0x17c/0x190
? handle_bug+0x3c/0x60
? exc_invalid_op+0x14/0x70
? asm_exc_invalid_op+0x16/0x20
? refcount_warn_saturate+0xd8/0xe0
cmd_ent_put+0x13b/0x160 [mlx5_core]
mlx5_cmd_comp_handler+0x5f9/0x670 [mlx5_core]
cmd_comp_notifier+0x1f/0x30 [mlx5_core]
notifier_call_chain+0x35/0xb0
atomic_notifier_call_chain+0x16/0x20
mlx5_eq_async_int+0xf6/0x290 [mlx5_core]
notifier_call_chain+0x35/0xb0
atomic_notifier_call_chain+0x16/0x20
irq_int_handler+0x19/0x30 [mlx5_core]
__handle_irq_event_percpu+0x4b/0x160
handle_irq_event+0x2e/0x80
handle_edge_irq+0x98/0x230
__common_interrupt+0x3b/0xa0
common_interrupt+0x7b/0xa0
</IRQ>
<TASK>
asm_common_interrupt+0x22/0x40 |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: fix a possible memleak in tipc_buf_append
__skb_linearize() doesn't free the skb when it fails, so move
'*buf = NULL' after __skb_linearize(), so that the skb can be
freed on the err path. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/qeth: Fix kernel panic after setting hsuid
Symptom:
When the hsuid attribute is set for the first time on an IQD Layer3
device while the corresponding network interface is already UP,
the kernel will try to execute a napi function pointer that is NULL.
Example:
---------------------------------------------------------------------------
[ 2057.572696] illegal operation: 0001 ilc:1 [#1] SMP
[ 2057.572702] Modules linked in: af_iucv qeth_l3 zfcp scsi_transport_fc sunrpc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6
nft_reject nft_ct nf_tables_set nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables libcrc32c nfnetlink ghash_s390 prng xts aes_s390 des_s390 de
s_generic sha3_512_s390 sha3_256_s390 sha512_s390 vfio_ccw vfio_mdev mdev vfio_iommu_type1 eadm_sch vfio ext4 mbcache jbd2 qeth_l2 bridge stp llc dasd_eckd_mod qeth dasd_mod
qdio ccwgroup pkey zcrypt
[ 2057.572739] CPU: 6 PID: 60182 Comm: stress_client Kdump: loaded Not tainted 4.18.0-541.el8.s390x #1
[ 2057.572742] Hardware name: IBM 3931 A01 704 (LPAR)
[ 2057.572744] Krnl PSW : 0704f00180000000 0000000000000002 (0x2)
[ 2057.572748] R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[ 2057.572751] Krnl GPRS: 0000000000000004 0000000000000000 00000000a3b008d8 0000000000000000
[ 2057.572754] 00000000a3b008d8 cb923a29c779abc5 0000000000000000 00000000814cfd80
[ 2057.572756] 000000000000012c 0000000000000000 00000000a3b008d8 00000000a3b008d8
[ 2057.572758] 00000000bab6d500 00000000814cfd80 0000000091317e46 00000000814cfc68
[ 2057.572762] Krnl Code:#0000000000000000: 0000 illegal
>0000000000000002: 0000 illegal
0000000000000004: 0000 illegal
0000000000000006: 0000 illegal
0000000000000008: 0000 illegal
000000000000000a: 0000 illegal
000000000000000c: 0000 illegal
000000000000000e: 0000 illegal
[ 2057.572800] Call Trace:
[ 2057.572801] ([<00000000ec639700>] 0xec639700)
[ 2057.572803] [<00000000913183e2>] net_rx_action+0x2ba/0x398
[ 2057.572809] [<0000000091515f76>] __do_softirq+0x11e/0x3a0
[ 2057.572813] [<0000000090ce160c>] do_softirq_own_stack+0x3c/0x58
[ 2057.572817] ([<0000000090d2cbd6>] do_softirq.part.1+0x56/0x60)
[ 2057.572822] [<0000000090d2cc60>] __local_bh_enable_ip+0x80/0x98
[ 2057.572825] [<0000000091314706>] __dev_queue_xmit+0x2be/0xd70
[ 2057.572827] [<000003ff803dd6d6>] afiucv_hs_send+0x24e/0x300 [af_iucv]
[ 2057.572830] [<000003ff803dd88a>] iucv_send_ctrl+0x102/0x138 [af_iucv]
[ 2057.572833] [<000003ff803de72a>] iucv_sock_connect+0x37a/0x468 [af_iucv]
[ 2057.572835] [<00000000912e7e90>] __sys_connect+0xa0/0xd8
[ 2057.572839] [<00000000912e9580>] sys_socketcall+0x228/0x348
[ 2057.572841] [<0000000091514e1a>] system_call+0x2a6/0x2c8
[ 2057.572843] Last Breaking-Event-Address:
[ 2057.572844] [<0000000091317e44>] __napi_poll+0x4c/0x1d8
[ 2057.572846]
[ 2057.572847] Kernel panic - not syncing: Fatal exception in interrupt
-------------------------------------------------------------------------------------------
Analysis:
There is one napi structure per out_q: card->qdio.out_qs[i].napi
The napi.poll functions are set during qeth_open().
Since
commit 1cfef80d4c2b ("s390/qeth: Don't call dev_close/dev_open (DOWN/UP)")
qeth_set_offline()/qeth_set_online() no longer call dev_close()/
dev_open(). So if qeth_free_qdio_queues() cleared
card->qdio.out_qs[i].napi.poll while the network interface was UP and the
card was offline, they are not set again.
Reproduction:
chzdev -e $devno layer2=0
ip link set dev $network_interface up
echo 0 > /sys/bus/ccw
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
mm/userfaultfd: reset ptes when close() for wr-protected ones
Userfaultfd unregister includes a step to remove wr-protect bits from all
the relevant pgtable entries, but that only covered an explicit
UFFDIO_UNREGISTER ioctl, not a close() on the userfaultfd itself. Cover
that too. This fixes a WARN trace.
The only user visible side effect is the user can observe leftover
wr-protect bits even if the user close()ed on an userfaultfd when
releasing the last reference of it. However hopefully that should be
harmless, and nothing bad should happen even if so.
This change is now more important after the recent page-table-check
patch we merged in mm-unstable (446dd9ad37d0 ("mm/page_table_check:
support userfault wr-protect entries")), as we'll do sanity check on
uffd-wp bits without vma context. So it's better if we can 100%
guarantee no uffd-wp bit leftovers, to make sure each report will be
valid. |
| In the Linux kernel, the following vulnerability has been resolved:
bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS
bits_per() rounds up to the next power of two when passed a power of
two. This causes crashes on some machines and configurations. |
| In the Linux kernel, the following vulnerability has been resolved:
geneve: fix header validation in geneve[6]_xmit_skb
syzbot is able to trigger an uninit-value in geneve_xmit() [1]
Problem : While most ip tunnel helpers (like ip_tunnel_get_dsfield())
uses skb_protocol(skb, true), pskb_inet_may_pull() is only using
skb->protocol.
If anything else than ETH_P_IPV6 or ETH_P_IP is found in skb->protocol,
pskb_inet_may_pull() does nothing at all.
If a vlan tag was provided by the caller (af_packet in the syzbot case),
the network header might not point to the correct location, and skb
linear part could be smaller than expected.
Add skb_vlan_inet_prepare() to perform a complete mac validation.
Use this in geneve for the moment, I suspect we need to adopt this
more broadly.
v4 - Jakub reported v3 broke l2_tos_ttl_inherit.sh selftest
- Only call __vlan_get_protocol() for vlan types.
v2,v3 - Addressed Sabrina comments on v1 and v2
[1]
BUG: KMSAN: uninit-value in geneve_xmit_skb drivers/net/geneve.c:910 [inline]
BUG: KMSAN: uninit-value in geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030
geneve_xmit_skb drivers/net/geneve.c:910 [inline]
geneve_xmit+0x302d/0x5420 drivers/net/geneve.c:1030
__netdev_start_xmit include/linux/netdevice.h:4903 [inline]
netdev_start_xmit include/linux/netdevice.h:4917 [inline]
xmit_one net/core/dev.c:3531 [inline]
dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547
__dev_queue_xmit+0x348d/0x52c0 net/core/dev.c:4335
dev_queue_xmit include/linux/netdevice.h:3091 [inline]
packet_xmit+0x9c/0x6c0 net/packet/af_packet.c:276
packet_snd net/packet/af_packet.c:3081 [inline]
packet_sendmsg+0x8bb0/0x9ef0 net/packet/af_packet.c:3113
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:745
__sys_sendto+0x685/0x830 net/socket.c:2191
__do_sys_sendto net/socket.c:2203 [inline]
__se_sys_sendto net/socket.c:2199 [inline]
__x64_sys_sendto+0x125/0x1d0 net/socket.c:2199
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
Uninit was created at:
slab_post_alloc_hook mm/slub.c:3804 [inline]
slab_alloc_node mm/slub.c:3845 [inline]
kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
__alloc_skb+0x35b/0x7a0 net/core/skbuff.c:668
alloc_skb include/linux/skbuff.h:1318 [inline]
alloc_skb_with_frags+0xc8/0xbf0 net/core/skbuff.c:6504
sock_alloc_send_pskb+0xa81/0xbf0 net/core/sock.c:2795
packet_alloc_skb net/packet/af_packet.c:2930 [inline]
packet_snd net/packet/af_packet.c:3024 [inline]
packet_sendmsg+0x722d/0x9ef0 net/packet/af_packet.c:3113
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0x30f/0x380 net/socket.c:745
__sys_sendto+0x685/0x830 net/socket.c:2191
__do_sys_sendto net/socket.c:2203 [inline]
__se_sys_sendto net/socket.c:2199 [inline]
__x64_sys_sendto+0x125/0x1d0 net/socket.c:2199
do_syscall_64+0xd5/0x1f0
entry_SYSCALL_64_after_hwframe+0x6d/0x75
CPU: 0 PID: 5033 Comm: syz-executor346 Not tainted 6.9.0-rc1-syzkaller-00005-g928a87efa423 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Protect against int overflow for stack access size
This patch re-introduces protection against the size of access to stack
memory being negative; the access size can appear negative as a result
of overflowing its signed int representation. This should not actually
happen, as there are other protections along the way, but we should
protect against it anyway. One code path was missing such protections
(fixed in the previous patch in the series), causing out-of-bounds array
accesses in check_stack_range_initialized(). This patch causes the
verification of a program with such a non-sensical access size to fail.
This check used to exist in a more indirect way, but was inadvertendly
removed in a833a17aeac7. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt7921e: fix use-after-free in free_irq()
From commit a304e1b82808 ("[PATCH] Debug shared irqs"), there is a test
to make sure the shared irq handler should be able to handle the unexpected
event after deregistration. For this case, let's apply MT76_REMOVED flag to
indicate the device was removed and do not run into the resource access
anymore.
BUG: KASAN: use-after-free in mt7921_irq_handler+0xd8/0x100 [mt7921e]
Read of size 8 at addr ffff88824a7d3b78 by task rmmod/11115
CPU: 28 PID: 11115 Comm: rmmod Tainted: G W L 5.17.0 #10
Hardware name: Micro-Star International Co., Ltd. MS-7D73/MPG B650I
EDGE WIFI (MS-7D73), BIOS 1.81 01/05/2024
Call Trace:
<TASK>
dump_stack_lvl+0x6f/0xa0
print_address_description.constprop.0+0x1f/0x190
? mt7921_irq_handler+0xd8/0x100 [mt7921e]
? mt7921_irq_handler+0xd8/0x100 [mt7921e]
kasan_report.cold+0x7f/0x11b
? mt7921_irq_handler+0xd8/0x100 [mt7921e]
mt7921_irq_handler+0xd8/0x100 [mt7921e]
free_irq+0x627/0xaa0
devm_free_irq+0x94/0xd0
? devm_request_any_context_irq+0x160/0x160
? kobject_put+0x18d/0x4a0
mt7921_pci_remove+0x153/0x190 [mt7921e]
pci_device_remove+0xa2/0x1d0
__device_release_driver+0x346/0x6e0
driver_detach+0x1ef/0x2c0
bus_remove_driver+0xe7/0x2d0
? __check_object_size+0x57/0x310
pci_unregister_driver+0x26/0x250
__do_sys_delete_module+0x307/0x510
? free_module+0x6a0/0x6a0
? fpregs_assert_state_consistent+0x4b/0xb0
? rcu_read_lock_sched_held+0x10/0x70
? syscall_enter_from_user_mode+0x20/0x70
? trace_hardirqs_on+0x1c/0x130
do_syscall_64+0x5c/0x80
? trace_hardirqs_on_prepare+0x72/0x160
? do_syscall_64+0x68/0x80
? trace_hardirqs_on_prepare+0x72/0x160
entry_SYSCALL_64_after_hwframe+0x44/0xae |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: af_bluetooth: Fix deadlock
Attemting to do sock_lock on .recvmsg may cause a deadlock as shown
bellow, so instead of using sock_sock this uses sk_receive_queue.lock
on bt_sock_ioctl to avoid the UAF:
INFO: task kworker/u9:1:121 blocked for more than 30 seconds.
Not tainted 6.7.6-lemon #183
Workqueue: hci0 hci_rx_work
Call Trace:
<TASK>
__schedule+0x37d/0xa00
schedule+0x32/0xe0
__lock_sock+0x68/0xa0
? __pfx_autoremove_wake_function+0x10/0x10
lock_sock_nested+0x43/0x50
l2cap_sock_recv_cb+0x21/0xa0
l2cap_recv_frame+0x55b/0x30a0
? psi_task_switch+0xeb/0x270
? finish_task_switch.isra.0+0x93/0x2a0
hci_rx_work+0x33a/0x3f0
process_one_work+0x13a/0x2f0
worker_thread+0x2f0/0x410
? __pfx_worker_thread+0x10/0x10
kthread+0xe0/0x110
? __pfx_kthread+0x10/0x10
ret_from_fork+0x2c/0x50
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1b/0x30
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
wireguard: receive: annotate data-race around receiving_counter.counter
Syzkaller with KCSAN identified a data-race issue when accessing
keypair->receiving_counter.counter. Use READ_ONCE() and WRITE_ONCE()
annotations to mark the data race as intentional.
BUG: KCSAN: data-race in wg_packet_decrypt_worker / wg_packet_rx_poll
write to 0xffff888107765888 of 8 bytes by interrupt on cpu 0:
counter_validate drivers/net/wireguard/receive.c:321 [inline]
wg_packet_rx_poll+0x3ac/0xf00 drivers/net/wireguard/receive.c:461
__napi_poll+0x60/0x3b0 net/core/dev.c:6536
napi_poll net/core/dev.c:6605 [inline]
net_rx_action+0x32b/0x750 net/core/dev.c:6738
__do_softirq+0xc4/0x279 kernel/softirq.c:553
do_softirq+0x5e/0x90 kernel/softirq.c:454
__local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381
__raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline]
_raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210
spin_unlock_bh include/linux/spinlock.h:396 [inline]
ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline]
wg_packet_decrypt_worker+0x6c5/0x700 drivers/net/wireguard/receive.c:499
process_one_work kernel/workqueue.c:2633 [inline]
...
read to 0xffff888107765888 of 8 bytes by task 3196 on cpu 1:
decrypt_packet drivers/net/wireguard/receive.c:252 [inline]
wg_packet_decrypt_worker+0x220/0x700 drivers/net/wireguard/receive.c:501
process_one_work kernel/workqueue.c:2633 [inline]
process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706
worker_thread+0x525/0x730 kernel/workqueue.c:2787
... |
| In the Linux kernel, the following vulnerability has been resolved:
net: ip_tunnel: prevent perpetual headroom growth
syzkaller triggered following kasan splat:
BUG: KASAN: use-after-free in __skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
Read of size 1 at addr ffff88812fb4000e by task syz-executor183/5191
[..]
kasan_report+0xda/0x110 mm/kasan/report.c:588
__skb_flow_dissect+0x19d1/0x7a50 net/core/flow_dissector.c:1170
skb_flow_dissect_flow_keys include/linux/skbuff.h:1514 [inline]
___skb_get_hash net/core/flow_dissector.c:1791 [inline]
__skb_get_hash+0xc7/0x540 net/core/flow_dissector.c:1856
skb_get_hash include/linux/skbuff.h:1556 [inline]
ip_tunnel_xmit+0x1855/0x33c0 net/ipv4/ip_tunnel.c:748
ipip_tunnel_xmit+0x3cc/0x4e0 net/ipv4/ipip.c:308
__netdev_start_xmit include/linux/netdevice.h:4940 [inline]
netdev_start_xmit include/linux/netdevice.h:4954 [inline]
xmit_one net/core/dev.c:3548 [inline]
dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
__dev_queue_xmit+0x7c1/0x3d60 net/core/dev.c:4349
dev_queue_xmit include/linux/netdevice.h:3134 [inline]
neigh_connected_output+0x42c/0x5d0 net/core/neighbour.c:1592
...
ip_finish_output2+0x833/0x2550 net/ipv4/ip_output.c:235
ip_finish_output+0x31/0x310 net/ipv4/ip_output.c:323
..
iptunnel_xmit+0x5b4/0x9b0 net/ipv4/ip_tunnel_core.c:82
ip_tunnel_xmit+0x1dbc/0x33c0 net/ipv4/ip_tunnel.c:831
ipgre_xmit+0x4a1/0x980 net/ipv4/ip_gre.c:665
__netdev_start_xmit include/linux/netdevice.h:4940 [inline]
netdev_start_xmit include/linux/netdevice.h:4954 [inline]
xmit_one net/core/dev.c:3548 [inline]
dev_hard_start_xmit+0x13d/0x6d0 net/core/dev.c:3564
...
The splat occurs because skb->data points past skb->head allocated area.
This is because neigh layer does:
__skb_pull(skb, skb_network_offset(skb));
... but skb_network_offset() returns a negative offset and __skb_pull()
arg is unsigned. IOW, we skb->data gets "adjusted" by a huge value.
The negative value is returned because skb->head and skb->data distance is
more than 64k and skb->network_header (u16) has wrapped around.
The bug is in the ip_tunnel infrastructure, which can cause
dev->needed_headroom to increment ad infinitum.
The syzkaller reproducer consists of packets getting routed via a gre
tunnel, and route of gre encapsulated packets pointing at another (ipip)
tunnel. The ipip encapsulation finds gre0 as next output device.
This results in the following pattern:
1). First packet is to be sent out via gre0.
Route lookup found an output device, ipip0.
2).
ip_tunnel_xmit for gre0 bumps gre0->needed_headroom based on the future
output device, rt.dev->needed_headroom (ipip0).
3).
ip output / start_xmit moves skb on to ipip0. which runs the same
code path again (xmit recursion).
4).
Routing step for the post-gre0-encap packet finds gre0 as output device
to use for ipip0 encapsulated packet.
tunl0->needed_headroom is then incremented based on the (already bumped)
gre0 device headroom.
This repeats for every future packet:
gre0->needed_headroom gets inflated because previous packets' ipip0 step
incremented rt->dev (gre0) headroom, and ipip0 incremented because gre0
needed_headroom was increased.
For each subsequent packet, gre/ipip0->needed_headroom grows until
post-expand-head reallocations result in a skb->head/data distance of
more than 64k.
Once that happens, skb->network_header (u16) wraps around when
pskb_expand_head tries to make sure that skb_network_offset() is unchanged
after the headroom expansion/reallocation.
After this skb_network_offset(skb) returns a different (and negative)
result post headroom expansion.
The next trip to neigh layer (or anything else that would __skb_pull the
network header) makes skb->data point to a memory location outside
skb->head area.
v2: Cap the needed_headroom update to an arbitarily chosen upperlimit to
prevent perpetual increase instead of dropping the headroom increment
completely. |
| In the Linux kernel, the following vulnerability has been resolved:
inet: read sk->sk_family once in inet_recv_error()
inet_recv_error() is called without holding the socket lock.
IPv6 socket could mutate to IPv4 with IPV6_ADDRFORM
socket option and trigger a KCSAN warning. |
