| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
io_uring/waitid: honor task_work cancellation
io_waitid_cb() may run through the fallback task_work path when
task_work_add() can no longer queue work to the originating task. The
fallback runs from a kworker and io_uring marks such task work as
canceled through tw.cancel.
io_waitid_cb() currently ignores tw.cancel and calls __do_wait().
waitid is task-context dependent: __do_wait() performs child lookup
relative to current, and the retry path also uses
current->signal->wait_chldexit. If the callback runs from the fallback
kworker, current is therefore not the task that submitted the request.
Honor tw.cancel before entering __do_wait(). Complete the request with
-ECANCELED and skip the siginfo copy, since canceled task work may run
without the submitting task's userspace execution context.
Keep the existing siginfo handling for normal waitid completion and
explicit cancellation. |
| In the Linux kernel, the following vulnerability has been resolved:
interconnect: Fix use after free in icc_get() and of_icc_get_by_index()
In of_icc_get_by_index() and icc_get(), if the dynamic allocation for
path->name fails via kasprintf(), the error handling path directly
calls kfree(path) to free the path object and returns an error.
However, prior to this point, path_find() calls path_init(), which
already links the path's requests into the req_list of the respective
interconnect nodes via hlist_add_head(). Directly invoking kfree(path)
leaves dangling pointers in the hlist. A subsequent call to icc_get()
or icc_set_bw() will traverse or modify these corrupted lists, triggering
a slab use afterfree.
KASAN report showing the vulnerability when reproducing via debugfs:
BUG: KASAN: slab-use-after-free in path_find+0x6f8/0xcfc
Write of size 8 at addr fff000000d43f748 by task sh/1
...
Call trace:
kasan_report+0xac/0xfc
path_find+0x6f8/0xcfc
icc_get+0x148/0x380
icc_get_set+0xf8/0x2d0
...
Freed by task 1:
kfree+0x1a0/0x4a4
icc_get+0x2cc/0x380
icc_get_set+0xf8/0x2d0
Fix this by replacing kfree(path) with the proper teardown function,
icc_put(path), which safely removes the requests from the req_list using
hlist_del() and drops the provider usage references before freeing the
memory.
Additionally, in icc_get(), ensure that the icc_lock mutex is released
prior to calling icc_put(path) to avoid a deadlock, as icc_put()
internally acquires the same lock. |
| In the Linux kernel, the following vulnerability has been resolved:
ipmi: Remove all sysfs files on registration failure
ipmi_add_smi() creates the nr_users and nr_msgs files before trying to
create the maintenance_mode file. If that last creation fails, the error
path removes only nr_users before dropping the final reference to the
interface.
Remove nr_msgs as well so no sysfs attribute embedded in the freed
interface remains registered. |
| In the Linux kernel, the following vulnerability has been resolved:
ipmi:msghandler: Cancel work cleanly on an error
If an error occurs during startup of an IPMI interface, it may have
scheduled work to run. The work needs to be canceled before the
interface can be freed. |
| In the Linux kernel, the following vulnerability has been resolved:
xdp: fix zero-copy frame layout
xdp_convert_zc_to_xdp_frame() clones an XSK packet into an order-0 page
and advertises PAGE_SIZE as its frame size. It allows the copied frame
to occupy the page tail needed by skb_shared_info and records zero
headroom even when metadata separates the frame header from packet data.
An AF_XDP zero-copy packet redirected through cpumap can therefore make
the skb overlap skb_shared_info or place it beyond the allocated page.
Limit the copied layout to SKB_WITH_OVERHEAD(PAGE_SIZE) and include the
metadata length in frame headroom. Redirect callers already handle a
NULL conversion result.
BUG: KASAN: slab-out-of-bounds in skb_gro_receive
Write of size 4 at addr ffff88800cf37004 by task cpumap/1/map:1/146
Call Trace:
skb_gro_receive (net/core/gro.c:174)
udp_gro_receive (net/ipv4/udp_offload.c:812)
inet_gro_receive (net/ipv4/af_inet.c:1539)
dev_gro_receive (net/core/gro.c:515)
gro_receive_skb (net/core/gro.c:633)
cpu_map_kthread_run (kernel/bpf/cpumap.c:395)
kthread (kernel/kthread.c:436)
ret_from_fork (arch/x86/kernel/process.c:164)
ret_from_fork_asm (arch/x86/entry/entry_64.S:255)
Kernel panic - not syncing: KASAN: panic_on_warn set ... |
| In the Linux kernel, the following vulnerability has been resolved:
slip: fix use-after-free in sl_sync()
slip_devs[] stores bare net_device pointers and takes no reference on
them. sl_sync() and sl_alloc() walk that table from slip_open() under
rtnl_lock(), while an entry is dropped by sl_free_netdev(), which
sl_setup() installs as dev->priv_destructor.
priv_destructor is called from netdev_run_todo(), which deliberately
runs with the RTNL semaphore released so that it can sleep while waiting
for the device refcount to drop:
/* Snapshot list, allow later requests */
list_replace_init(&net_todo_list, &list);
__rtnl_unlock();
...
if (dev->priv_destructor)
dev->priv_destructor(dev); /* slip_devs[i] = NULL */
if (dev->needs_free_netdev)
free_netdev(dev);
...
/* Free network device */
kobject_put(&dev->dev.kobj);
So rtnl_lock() does not serialise slip_open() against the teardown at
all. sl_sync() can load slip_devs[i] while the entry is still published
and dereference it after netdev_run_todo() has run the destructor and
released the device:
CPU0 (slip_open) CPU1 (slip_close)
unregister_netdev()
rtnl_unlock()
netdev_run_todo()
__rtnl_unlock()
rtnl_lock()
sl_sync()
dev = slip_devs[i]
priv_destructor(dev)
slip_devs[i] = NULL
kobject_put(&dev->dev.kobj)
/* dev is freed */
sl = netdev_priv(dev)
if (sl->tty || sl->leased) /* use-after-free */
BUG: KASAN: use-after-free in sl_sync drivers/net/slip/slip.c:730 [inline]
BUG: KASAN: use-after-free in slip_open+0xef4/0x1210 drivers/net/slip/slip.c:806
Read of size 1 at addr ffff8880712dac71 by task syz-executor.2/6506
CPU: 2 PID: 6506 Comm: syz-executor.2 Not tainted 6.1.134-syzkaller-00260-g0c8fc3469765 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
sl_sync drivers/net/slip/slip.c:730 [inline]
slip_open+0xef4/0x1210 drivers/net/slip/slip.c:806
tty_ldisc_open+0xa2/0x120 drivers/tty/tty_ldisc.c:433
tty_set_ldisc+0x324/0x720 drivers/tty/tty_ldisc.c:564
tiocsetd drivers/tty/tty_io.c:2428 [inline]
tty_ioctl+0x5f0/0x1530 drivers/tty/tty_io.c:2712
Allocated by task 6502:
alloc_netdev_mqs+0x98/0xfe0 net/core/dev.c:10719
sl_alloc drivers/net/slip/slip.c:756 [inline]
slip_open+0x36d/0x1210 drivers/net/slip/slip.c:817
tty_ldisc_open+0xa2/0x120 drivers/tty/tty_ldisc.c:433
tty_set_ldisc+0x324/0x720 drivers/tty/tty_ldisc.c:564
Freed by task 6497:
device_release+0xa2/0x240 drivers/base/core.c:2507
kobject_put+0x179/0x280 lib/kobject.c:729
netdev_run_todo+0x6c8/0xef0 net/core/dev.c:10509
slip_close+0x166/0x1c0 drivers/net/slip/slip.c:906
tty_ldisc_close+0x113/0x1a0 drivers/tty/tty_ldisc.c:456
tty_ldisc_kill+0x94/0x160 drivers/tty/tty_ldisc.c:614
tty_ldisc_release+0xe3/0x2b0 drivers/tty/tty_ldisc.c:782
tty_release+0xbcc/0xe70 drivers/tty/tty_io.c:1860
Commit e58c19124189 ("slip: Fix use-after-free Read in slip_open") fixed
a different source of stale entries - a device left in slip_devs[] after
slip_open() freed it on the registration error path - and does not
address this race, which is why the report survives it.
Drop the entry from ndo_uninit instead. unregister_netdevice() calls
ndo_uninit under RTNL, before the device is queued to netdev_run_todo(),
so an entry that sl_sync() can still see while holding RTNL belongs to a
device that cannot be freed until RTNL is dropped. sl_free_netdev()
stays only for the slip_open() error path, where register_netdevice()
may have failed before ndo_init and ndo_uninit is then not called
either. Both running for the same device is harmless: the
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net: tun: bound receive headroom
tun_get_user() uses tun->align both as skb headroom and when choosing how
much packet data to keep linear. OVS can propagate an oversized headroom
request from another port to TUN or TAP.
When align is larger than the usable space in a one-page skb head,
SKB_MAX_HEAD(align) underflows and the result becomes negative when stored
in good_linear. That value later wraps when assigned to the size_t linear
variable, and tun_alloc_skb() can place skb->data outside the allocated
head.
Bound the headroom stored by TUN to the one-page skb-head budget and the
largest non-sentinel 16-bit skb header offset. Leave one linear byte for
raw TUN and a complete Ethernet header for TAP, including NET_IP_ALIGN.
Also pull the raw-TUN protocol byte and the TAP Ethernet header before
accessing them, so these checks remain safe for nonlinear skbs supplied by
other allocation paths. |
| In the Linux kernel, the following vulnerability has been resolved:
net: bnxt: ring the doorbell when SW USO exits early
When a burst of packets is handed down to the driver, the driver defers
the doorbell to the end by setting txr->kick_pending = 1. The normal TX
path handles this, but the SW USO path can miss it if it returns
early.
If bnxt_sw_udp_gso_xmit runs but returns early with NETDEV_TX_BUSY and
txr->kick_pending was previously set to 1, then the TX queue can
stall because the driver wrote some BDs but never wrote the doorbell.
The device won't know to do the TX which would generate the completion
that would wake the queue back up.
Simplify bnxt_sw_udp_gso_xmit to set txr->kick_pending in its success
case and check the flag on return. The added check after
bnxt_sw_udp_gso_xmit returns ensures that any pending doorbells are
written handling both successful USO and any early returns, which
prevents the TX queue stall mentioned above.
This TX queue stall was observed on a production system with a netdev TX
watchdog informing about the queue stall. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ipa: fix stalled modem TX queue after runtime resume
ipa_start_xmit() unconditionally stops the TX queue before calling
pm_runtime_get(), relying on the wake scheduled by runtime resume
(ipa_modem_wake_queue_work()) to restart it once power is ACTIVE.
But that work is queued from within the runtime resume callback,
before the device's power state reaches RPM_ACTIVE, so it can run
while the device is still RPM_RESUMING. The wake is then consumed
too early: the transmit it restarts stops the queue again,
pm_runtime_get() returns -EINPROGRESS without arranging any future
wake (deferred_resume exists only for RPM_SUSPENDING), and after the
resume completes nothing is left to wake the queue. Transmit stalls
permanently: packets pile up in the qdisc behind the stopped queue,
the device runtime-suspends, and since the netdev registers no
ndo_tx_timeout the watchdog never fires. Observed on SM7635
(Fairphone 6) as the cellular data path going permanently deaf
within hours, RX included, since nothing resumes the suspended
endpoints.
Close the window by making the wake work wait for the resume to
complete (pm_runtime_get_sync()) before waking the queue. Every
queue stop is then guaranteed a later wake that happens while power
is ACTIVE; a transmit racing a new suspend/resume cycle re-schedules
the work. If the device could not be resumed, wake the queue anyway
so pending packets are dropped by the transmit path rather than
stranded.
The STARTED power flag used to narrow this window: a wake running
before the transmit path's stop suppressed that stop, but only once,
as the flag was cleared by the first stop it absorbed. Removing the
flag made a single transmit during an in-flight resume sufficient to
strand the queue, which is the form observed.
With an accelerated reproducer (autosuspend delay shortened to 5 ms,
~20 packets/s of TX), an unpatched kernel stalled three times in
230 s / 4380 packets; with this patch the same test ran 3601 s /
70298 packets without a stall. |
| In the Linux kernel, the following vulnerability has been resolved:
net: mctp: hold a reference to the route device in mctp_route_lookup()
mctp_route_lookup() uses rt->dev without holding a reference on it.
mctp_route_lookup_single() returns the route under RCU only, so the
route's device can be torn down concurrently: mctp_dev_put() drops the
last reference and synchronously kfree()s mdev->addrs. mctp_dev_saddr()
then reads rt->dev->addrs[0], giving a use-after-free reachable by an
unprivileged local AF_MCTP user on the receive/forwarding path (no
CAP_NET_RAW required):
BUG: KASAN: slab-use-after-free in mctp_route_lookup
Read of size 1 at addr ... by task mctp_uaf/...
mctp_route_lookup
mctp_pkttype_receive
Freed by task ...:
kfree
mctp_dev_put
mctp_dev_notify
In the same window mctp_dst_from_route() -> mctp_dev_hold() also
increments a refcount that has already reached zero
("refcount_t: addition on 0 ... mctp_dev_hold").
This reintroduces the use-after-free class of CVE-2023-3439: the source
address lookup was moved ahead of the point where the destination takes
its device reference.
Take a reference with refcount_inc_not_zero() before touching rt->dev,
skip a device that is already dead, and drop the reference once the
destination has taken its own. |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: fix flow mask use-after-free on flow deletion
The commit in the Fixes tag below made so flow->mask free is scheduled
via RCU right after it is removed from the flow table. The pointer
stays in the flow structure and it can be accessible while in the same
RCU critical section. This is done to avoid requiring ovs_mutex for
the ovs_flow_free().
However, while removing the flow during processing of CMD_DEL, we do
not take RCU read lock before the removal, and ovs_flow_cmd_fill_info()
uses the flow->mask pointer afterwards. The RCU read lock is taken,
but it's already late at that point. The comment on that line
acknowledges that the lock is cosmetic and doesn't serve a real purpose.
This leads to use-after-free if the RCU grace period passes between
removal and the filling. It is a short race window, but it is there
and can lead to a real crash in case memory allocation for the info
takes a bit longer:
BUG: KASAN: slab-use-after-free in __ovs_nla_put_key
net/openvswitch/flow_netlink.c:1996
BUG: KASAN: slab-use-after-free in ovs_nla_put_key+0x2463/0x2e30
net/openvswitch/flow_netlink.c:2250
Read of size 4 at addr ffff88801ee89970 by task ovs_flow_del_ec/9487
Call Trace:
<TASK>
__ovs_nla_put_key net/openvswitch/flow_netlink.c:1996
ovs_nla_put_key+0x2463/0x2e30 net/openvswitch/flow_netlink.c:2250
ovs_flow_cmd_fill_info+0x420/0x9c0 net/openvswitch/datapath.c:930
ovs_flow_cmd_del+0x53a/0x970 net/openvswitch/datapath.c:1467
...
netlink_rcv_skb+0x156/0x420 net/netlink/af_netlink.c:2556
</TASK>
Allocated by task 9487:
mask_alloc net/openvswitch/flow_table.c:967
flow_mask_insert net/openvswitch/flow_table.c:1012
ovs_flow_tbl_insert+0xea2/0x1a90 net/openvswitch/flow_table.c:1084
ovs_flow_cmd_new+0x7e3/0xd90 net/openvswitch/datapath.c:1086
...
netlink_rcv_skb+0x156/0x420 net/netlink/af_netlink.c:2556
Freed by task 9485:
rcu_free_sheaf+0x1e/0x100 mm/slub.c:5978
rcu_do_batch kernel/rcu/tree.c:2645
rcu_core+0x59c/0x10c0 kernel/rcu/tree.c:2897
handle_softirqs+0x1e4/0x9a0 kernel/softirq.c:622
...
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062
ovs_flow_tbl_remove() must be called after the ovs_flow_cmd_fill_info()
to avoid this race. This also helps with cleaning up the forced cast
and the cosmetic RCU read lock. Before the commit in the Fixes tag the
order did not matter as long as the flow object itself was not freed.
A wider RCU critical section could be another option, but we have a
GFP_KERNEL allocation in the way.
Reported by Trend Micro's Zero Day Initiative as ZDI-CAN-32042. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ravb: avoid dereferencing an invalid PTP clock
The PTP clock is unavailable before the first open, so querying its
index can dereference a NULL pointer. Registration failures can also
leave an error pointer in priv->ptp.clock.
Cache the PHC index separately and report -1 while no clock is
registered. Normalize registration errors to NULL and preserve the
static timestamping capabilities. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ravb: serialize PTP clock teardown
ravb_ptp_interrupt() can race with ravb_ptp_stop() and pass the clock to
ptp_clock_event() while ptp_clock_unregister() is freeing it. This can
lead to a use-after-free.
Use READ_ONCE() and WRITE_ONCE() for lockless access to the clock pointer.
Atomically detach it with xchg() before disabling PTP interrupts, then
synchronize all IRQs which can invoke ravb_ptp_interrupt() before
unregistering the detached clock.
A handler which read the old pointer completes before the clock is
unregistered, while later handlers read NULL and skip the event. |
| In the Linux kernel, the following vulnerability has been resolved:
net: thunderbolt: Mark the connection down when bringing it up fails
Every failure path in tbnet_connected_work() undoes its own work and
returns without clearing login_sent, so the connection still looks
established. The next tbnet_tear_down() therefore takes its main branch
and repeats a teardown that already happened: it stops rings that are
already stopped, which is a dev_WARN() and fatal under panic_on_warn,
and it releases net->remote_transmit_path even on the HopID mismatch
path, where this connection never owned that id, silently freeing one
that someone else is still using.
Clear login_sent on those paths. That is enough for tbnet_tear_down() to
leave the unwound state alone, and login_received has to stay set: it
records that the peer has logged in and carries the transmit path it gave
us, which nothing on this side can make the peer send again. Two things
change beyond keeping the teardown out of the way: the logout request in
that block is no longer sent, and the peer's next login request now
re-queues our login work rather than connected_work, giving the
connection a fresh login instead of a retry on stale state. |
| In the Linux kernel, the following vulnerability has been resolved:
NTB: ntb_transport: Reject oversized TX buffers
ntb_process_tx() handles an oversized buffer by calling tx_handler()
with a NULL data pointer and returning success. ntb_netdev therefore
neither frees the skb in its completion callback nor takes its enqueue
error path, leaking it.
Reject oversized buffers in ntb_transport_tx_enqueue() before acquiring
a queue entry and return -EMSGSIZE. The caller retains ownership of the
buffer, and the preceding netdev patch frees the skb when enqueue
returns this permanent error. |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: bound the peer rkey counts in SMC-Rv2 LLC messages
On a link whose device has max_recv_sge == 1 there is no shared v2 receive
buffer, and smc_llc_save_add_link_rkeys() takes the v2 extension from 44
bytes past the start of the queue entry's inline message:
ext = (struct smc_llc_msg_add_link_v2_ext *)(llc_msg + SMC_WR_TX_SIZE);
The entry is a 72-byte allocation and the extension starts at offset 68, so
ext->num_rkeys at offset 94 is already past it. This happens on every
SMC-Rv2 link addition, whatever the peer sends:
[ 2.490065] BUG: KASAN: slab-out-of-bounds in smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.490431] Read of size 2 at addr ffff8880056406de by task smctest/106
[ 2.490709]
[ 2.490792] CPU: 0 UID: 0 PID: 106 Comm: smctest Not tainted 7.2.0-rc5-p1-g77a5d9d9c99f #32 PREEMPT(lazy)
[ 2.490795] 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
[ 2.490798] Call Trace:
[ 2.490803] <TASK>
[ 2.490805] dump_stack_lvl+0x53/0x70
[ 2.490810] print_report+0xd0/0x630
[ 2.490828] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 2.490832] ? smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.490834] kasan_report+0xce/0x100
[ 2.490836] ? smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.490837] smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.490839] ? smcr_buf_map_lgr+0x1bf/0x2b0
[ 2.490844] smc_llc_cli_add_link+0xca7/0x1e80
[ 2.490848] ? smc_llc_wait+0x355/0x810
[ 2.490850] ? __pfx_smc_llc_wait+0x10/0x10
[ 2.490851] ? __pfx_smc_llc_cli_add_link+0x10/0x10
[ 2.490853] ? __pfx_autoremove_wake_function+0x10/0x10
[ 2.490863] __smc_connect+0x3f5c/0x4980
[ 2.490873] ? __pfx_kernel_connect+0x10/0x10
[ 2.490888] ? __pfx___smc_connect+0x10/0x10
[ 2.490891] ? release_sock+0x148/0x1d0
[ 2.490894] smc_connect+0x42c/0x580
[ 2.490896] __sys_connect+0xfc/0x130
[ 2.490898] ? __pfx___sys_connect+0x10/0x10
[ 2.490900] ? handle_mm_fault+0x1a1/0x430
[ 2.490908] __x64_sys_connect+0x6d/0xb0
[ 2.490909] ? fpregs_assert_state_consistent+0x56/0xe0
[ 2.490917] do_syscall_64+0xf9/0x540
[ 2.490921] entry_SYSCALL_64_after_hwframe+0x77/0x7f
[ 2.490924] RIP: 0033:0x421bb4
[ 2.490927] Code: ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d ad 34 09 00 00 74 13 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 4c c3 0f 1f 00 55 48 89 e5 48 83 ec 10 89 55
[ 2.490929] RSP: 002b:00007ffd473b01a8 EFLAGS: 00000202 ORIG_RAX: 000000000000002a
[ 2.490935] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000421bb4
[ 2.490936] RDX: 0000000000000010 RSI: 00007ffd473b01d0 RDI: 0000000000000003
[ 2.490937] RBP: 0000000000003930 R08: 0000000000000004 R09: 0000000000000000
[ 2.490938] R10: 00007ffd473b0f98 R11: 0000000000000202 R12: 0000000000000006
[ 2.490939] R13: 00007ffd473b0f87 R14: 0000000000000003 R15: 00007ffd473b0f90
[ 2.490940] </TASK>
[ 2.490941]
[ 2.499545] Allocated by task 44:
[ 2.499693] kasan_save_stack+0x33/0x60
[ 2.499860] kasan_save_track+0x14/0x30
[ 2.500026] __kasan_kmalloc+0x8f/0xa0
[ 2.500190] __kmalloc_cache_noprof+0x158/0x370
[ 2.500393] smc_llc_enqueue+0x72/0x560
[ 2.500559] smc_wr_rx_tasklet_fn+0x474/0xa80
[ 2.500747] tasklet_action_common+0x20f/0x8a0
[ 2.500945] handle_softirqs+0x18e/0x590
[ 2.501115] do_softirq+0x3b/0x60
[ 2.501266] __local_bh_enable_ip+0x61/0x70
[ 2.501446] __alloc_skb+0x732/0x890
[ 2.501604] rxe_init_packet+0x16b/0x4f0
[ 2.501783] prepare_ack_packet+0xb8/0x830
[ 2.501962] rxe_receiver+0x495/0x96e0
[ 2.502125] do_work+0x144/0x470
[ 2.502269] process_one_work+0x633/0x1030
[ 2.502450] worker_thread+0x45b/0xd10
[ 2.50261
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: carry oversized SMC-Rv2 LLC messages in the queue entry
smc_llc_rmt_delete_rkey() and smc_llc_save_add_link_rkeys() read the part
of a v2 message that does not fit into the 44-byte union smc_llc_msg, and
both bound themselves by the size of the buffer it landed in, not by what
arrived. On a link with a shared v2 receive buffer a 44-byte
DELETE_RKEY_V2 declaring 255 rkeys reaches rkey[9..254] in whatever an
earlier message left in lgr->wr_rx_buf_v2, and passes each of them to
smc_rtoken_delete(). One of those 255 matched a registered rtoken and
deleted it. An ADD_LINK on such a link installs up to 255 rtokens from
the same bytes.
Copy the tail into the queue entry, so its length is the length of the
message that arrived, and declare the rkeys that fit inline as a member of
the union instead of reaching them through a cast. The same
DELETE_RKEY_V2 now processes the 9 rkeys it carries. The copy is limited
to the longest tail the two functions can read, so the peer does not pick
the size of the entry.
The bound the previous patch placed on links without a shared v2 receive
buffer is no longer needed. |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix use-after-free in smc_rx_pipe_buf_release()
smc_rx_splice() hands RMB pages to a pipe and takes a socket reference
per entry so the smc_sock stays alive until the reader finishes. The
connection does not: a concurrent close runs smc_conn_free(), which
releases the receive buffer back to the link group pool.
smc_rx_pipe_buf_release() tests sk_state before taking the socket lock.
The state can change between the test and the lock, and
smc_rx_update_cons() then dereferences conn->rmb_desc and walks
conn->lgr, which smc_conn_free() has already released. On the
is_reg_err path smcr_buf_unuse() frees the descriptor outright, so
this is a use-after-free.
Take the socket lock first and test conn->freed instead.
smc_conn_free() sets that flag before releasing anything, and every
caller holds the socket lock. The two paths exclude each other: either
the pipe release runs first with everything valid, or it sees the flag
and skips the update. |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: fix use-after-free of the LLC qentry in smc_llc_srv_add_link()
smc_llc_srv_add_link() keeps add_llc pointing into the queue entry:
add_llc = &qentry->msg.add_link; smc_llc.c:1482
...
smc_llc_save_add_link_info(link_new, add_llc); smc_llc.c:1494
smc_llc_flow_qentry_del(&lgr->llc_flow_lcl); smc_llc.c:1495
...
u8 *llc_msg = smc_link_shared_v2_rxbuf(link) ?
(u8 *)lgr->wr_rx_buf_v2 : (u8 *)add_llc; smc_llc.c:1504
smc_llc_save_add_link_rkeys(link, link_new, llc_msg); smc_llc.c:1506
smc_llc_flow_qentry_del() kfree()s the entry, so on a link without a shared
v2 receive buffer the pointer handed to smc_llc_save_add_link_rkeys() is
already freed. Before the Fixes: commit that branch always used
lgr->wr_rx_buf_v2 and add_llc was not used after the free.
Reproduced on an unpatched tree over rxe, with KASAN, kasan_multi_shot
and a link forced to max_recv_sge == 1: the entry is freed and read by
the same call, and the freeing frame is smc_llc_srv_add_link() itself.
[ 2.523161] BUG: KASAN: slab-use-after-free in smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.523499] Read of size 2 at addr ffff8880052194de by task kworker/0:1/11
[ 2.523789]
[ 2.523862] CPU: 0 UID: 0 PID: 11 Comm: kworker/0:1 Not tainted 7.2.0-rc5-p0-g2c9dd296545d #35 PREEMPT(lazy)
[ 2.523865] 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
[ 2.523866] Workqueue: smc_hs_wq smc_listen_work
[ 2.523869] Call Trace:
[ 2.523870] <TASK>
[ 2.523871] dump_stack_lvl+0x53/0x70
[ 2.523872] print_report+0xd0/0x630
[ 2.523874] ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[ 2.523876] ? smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.523878] kasan_report+0xce/0x100
[ 2.523879] ? smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.523881] smc_llc_save_add_link_rkeys+0x333/0x350
[ 2.523883] ? smcr_buf_reg_lgr+0x2a4/0x660
[ 2.523885] smc_llc_srv_add_link+0xaa2/0x1e50
[ 2.523888] ? _printk+0xba/0xf0
[ 2.523897] ? __pfx_smc_llc_srv_add_link+0x10/0x10
[ 2.523899] ? down_write+0xb0/0x130
[ 2.523903] ? __pfx_down_write+0x10/0x10
[ 2.523905] smc_listen_work+0x489e/0x4d00
[ 2.523907] ? kmem_cache_free+0x1c6/0x3a0
[ 2.523911] ? __pfx_smc_listen_work+0x10/0x10
[ 2.523913] ? release_sock+0x148/0x1d0
[ 2.523915] ? smc_tcp_listen_work+0xb4f/0xfc0
[ 2.523917] ? _raw_spin_lock_irq+0x80/0xe0
[ 2.523918] ? __pfx__raw_spin_lock_irq+0x10/0x10
[ 2.523920] process_one_work+0x633/0x1030
[ 2.523922] ? assign_work+0x11d/0x370
[ 2.523924] worker_thread+0x45b/0xd10
[ 2.523926] ? __pfx_worker_thread+0x10/0x10
[ 2.523928] ? __pfx_worker_thread+0x10/0x10
[ 2.523929] kthread+0x2c6/0x3b0
[ 2.523931] ? recalc_sigpending+0x15c/0x1e0
[ 2.523934] ? __pfx_kthread+0x10/0x10
[ 2.523935] ret_from_fork+0x36e/0x5a0
[ 2.523937] ? __pfx_ret_from_fork+0x10/0x10
[ 2.523938] ? __switch_to+0x572/0xdd0
[ 2.523943] ? __pfx_kthread+0x10/0x10
[ 2.523944] ret_from_fork_asm+0x1a/0x30
[ 2.523947] </TASK>
[ 2.523948]
[ 2.531253] Allocated by task 48:
[ 2.531399] kasan_save_stack+0x33/0x60
[ 2.531570] kasan_save_track+0x14/0x30
[ 2.531737] __kasan_kmalloc+0x8f/0xa0
[ 2.531905] __kmalloc_cache_noprof+0x158/0x370
[ 2.532100] smc_llc_enqueue+0x72/0x560
[ 2.532268] smc_wr_rx_tasklet_fn+0x474/0xa80
[ 2.532491] tasklet_action_common+0x20f/0x8a0
[ 2.532714] handle_softirqs+0x18e/0x590
[ 2.532886] do_softirq+0x3b/0x60
[ 2.533036] __local_bh_enable_ip+0x61/0x70
[ 2.533221] __alloc_skb+0x732/0x890
[ 2.533384] rxe_init_packet+0x16b/0x4f0
[ 2.533567] prepare_ack_packet+0xb8/0x830
[ 2.533760] rxe_receiver+0x495/0x96e0
[ 2.533933] do_work+0x144/0x470
[ 2
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: stop killed, freed and out_of_sync sharing a byte
The three connection state flags are single-bit bitfields, so they occupy
one byte of struct smc_connection and every store to one is a
read-modify-write of the other two:
u8 killed : 1;
u8 freed : 1;
u8 out_of_sync : 1;
They are not written under a common lock. smc_cdc_msg_validate() sets
out_of_sync from the receive tasklet, while smc_conn_kill() sets killed
from process context under lock_sock(), and the receive path does not defer
to the backlog when the socket is owned -- smc_cdc_msg_recv() takes only
bh_lock_sock().
Give each flag its own byte so a store no longer touches its neighbours.
All readers test them as booleans and are unchanged. struct smc_connection
grows by two bytes. |
