| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| A use-after-free flaw was found in the Linux Kernel. When a disk is removed, bdi_unregister is called to stop further write-back and waits for associated delayed work to complete. However, wb_inode_writeback_end() may schedule bandwidth estimation work after this has completed, which can result in the timer attempting to access the recently freed bdi_writeback. |
| A flaw was found in OpenSSL's handling of the properties argument in certain functions. This vulnerability can allow use-after-free exploitation, which may result in undefined behavior or incorrect property parsing, leading to OpenSSL treating the input as an empty string. |
| In the Linux kernel, the following vulnerability has been resolved:
dma-buf/dma-resv: check if the new fence is really later
Previously when we added a fence to a dma_resv object we always
assumed the the newer than all the existing fences.
With Jason's work to add an UAPI to explicit export/import that's not
necessary the case any more. So without this check we would allow
userspace to force the kernel into an use after free error.
Since the change is very small and defensive it's probably a good
idea to backport this to stable kernels as well just in case others
are using the dma_resv object in the same way. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: Fix UAF in ieee80211_scan_rx()
ieee80211_scan_rx() tries to access scan_req->flags after a
null check, but a UAF is observed when the scan is completed
and __ieee80211_scan_completed() executes, which then calls
cfg80211_scan_done() leading to the freeing of scan_req.
Since scan_req is rcu_dereference()'d, prevent the racing in
__ieee80211_scan_completed() by ensuring that from mac80211's
POV it is no longer accessed from an RCU read critical section
before we call cfg80211_scan_done(). |
| In the Linux kernel, the following vulnerability has been resolved:
alloc_tag: allocate percpu counters for module tags dynamically
When a module gets unloaded it checks whether any of its tags are still in
use and if so, we keep the memory containing module's allocation tags
alive until all tags are unused. However percpu counters referenced by
the tags are freed by free_module(). This will lead to UAF if the memory
allocated by a module is accessed after module was unloaded.
To fix this we allocate percpu counters for module allocation tags
dynamically and we keep it alive for tags which are still in use after
module unloading. This also removes the requirement of a larger
PERCPU_MODULE_RESERVE when memory allocation profiling is enabled because
percpu memory for counters does not need to be reserved anymore. |
| In the Linux kernel, the following vulnerability has been resolved:
mlxsw: spectrum_router: Fix use-after-free when deleting GRE net devices
The driver only offloads neighbors that are constructed on top of net
devices registered by it or their uppers (which are all Ethernet). The
device supports GRE encapsulation and decapsulation of forwarded
traffic, but the driver will not offload dummy neighbors constructed on
top of GRE net devices as they are not uppers of its net devices:
# ip link add name gre1 up type gre tos inherit local 192.0.2.1 remote 198.51.100.1
# ip neigh add 0.0.0.0 lladdr 0.0.0.0 nud noarp dev gre1
$ ip neigh show dev gre1 nud noarp
0.0.0.0 lladdr 0.0.0.0 NOARP
(Note that the neighbor is not marked with 'offload')
When the driver is reloaded and the existing configuration is replayed,
the driver does not perform the same check regarding existing neighbors
and offloads the previously added one:
# devlink dev reload pci/0000:01:00.0
$ ip neigh show dev gre1 nud noarp
0.0.0.0 lladdr 0.0.0.0 offload NOARP
If the neighbor is later deleted, the driver will ignore the
notification (given the GRE net device is not its upper) and will
therefore keep referencing freed memory, resulting in a use-after-free
[1] when the net device is deleted:
# ip neigh del 0.0.0.0 lladdr 0.0.0.0 dev gre1
# ip link del dev gre1
Fix by skipping neighbor replay if the net device for which the replay
is performed is not our upper.
[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_neigh_entry_update+0x1ea/0x200
Read of size 8 at addr ffff888155b0e420 by task ip/2282
[...]
Call Trace:
<TASK>
dump_stack_lvl+0x6f/0xa0
print_address_description.constprop.0+0x6f/0x350
print_report+0x108/0x205
kasan_report+0xdf/0x110
mlxsw_sp_neigh_entry_update+0x1ea/0x200
mlxsw_sp_router_rif_gone_sync+0x2a8/0x440
mlxsw_sp_rif_destroy+0x1e9/0x750
mlxsw_sp_netdevice_ipip_ol_event+0x3c9/0xdc0
mlxsw_sp_router_netdevice_event+0x3ac/0x15e0
notifier_call_chain+0xca/0x150
call_netdevice_notifiers_info+0x7f/0x100
unregister_netdevice_many_notify+0xc8c/0x1d90
rtnl_dellink+0x34e/0xa50
rtnetlink_rcv_msg+0x6fb/0xb70
netlink_rcv_skb+0x131/0x360
netlink_unicast+0x426/0x710
netlink_sendmsg+0x75a/0xc20
__sock_sendmsg+0xc1/0x150
____sys_sendmsg+0x5aa/0x7b0
___sys_sendmsg+0xfc/0x180
__sys_sendmsg+0x121/0x1b0
do_syscall_64+0xbb/0x1d0
entry_SYSCALL_64_after_hwframe+0x4b/0x53 |
| In the Linux kernel, the following vulnerability has been resolved:
firmware_loader: Fix use-after-free during unregister
In the following code within firmware_upload_unregister(), the call to
device_unregister() could result in the dev_release function freeing the
fw_upload_priv structure before it is dereferenced for the call to
module_put(). This bug was found by the kernel test robot using
CONFIG_KASAN while running the firmware selftests.
device_unregister(&fw_sysfs->dev);
module_put(fw_upload_priv->module);
The problem is fixed by copying fw_upload_priv->module to a local variable
for use when calling device_unregister(). |
| In the Linux kernel, the following vulnerability has been resolved:
s390: fix double free of GS and RI CBs on fork() failure
The pointers for guarded storage and runtime instrumentation control
blocks are stored in the thread_struct of the associated task. These
pointers are initially copied on fork() via arch_dup_task_struct()
and then cleared via copy_thread() before fork() returns. If fork()
happens to fail after the initial task dup and before copy_thread(),
the newly allocated task and associated thread_struct memory are
freed via free_task() -> arch_release_task_struct(). This results in
a double free of the guarded storage and runtime info structs
because the fields in the failed task still refer to memory
associated with the source task.
This problem can manifest as a BUG_ON() in set_freepointer() (with
CONFIG_SLAB_FREELIST_HARDENED enabled) or KASAN splat (if enabled)
when running trinity syscall fuzz tests on s390x. To avoid this
problem, clear the associated pointer fields in
arch_dup_task_struct() immediately after the new task is copied.
Note that the RI flag is still cleared in copy_thread() because it
resides in thread stack memory and that is where stack info is
copied. |
| In the Linux kernel, the following vulnerability has been resolved:
writeback: avoid use-after-free after removing device
When a disk is removed, bdi_unregister gets called to stop further
writeback and wait for associated delayed work to complete. However,
wb_inode_writeback_end() may schedule bandwidth estimation dwork after
this has completed, which can result in the timer attempting to access the
just freed bdi_writeback.
Fix this by checking if the bdi_writeback is alive, similar to when
scheduling writeback work.
Since this requires wb->work_lock, and wb_inode_writeback_end() may get
called from interrupt, switch wb->work_lock to an irqsafe lock. |
| In the Linux kernel, the following vulnerability has been resolved:
rxrpc: Fix locking in rxrpc's sendmsg
Fix three bugs in the rxrpc's sendmsg implementation:
(1) rxrpc_new_client_call() should release the socket lock when returning
an error from rxrpc_get_call_slot().
(2) rxrpc_wait_for_tx_window_intr() will return without the call mutex
held in the event that we're interrupted by a signal whilst waiting
for tx space on the socket or relocking the call mutex afterwards.
Fix this by: (a) moving the unlock/lock of the call mutex up to
rxrpc_send_data() such that the lock is not held around all of
rxrpc_wait_for_tx_window*() and (b) indicating to higher callers
whether we're return with the lock dropped. Note that this means
recvmsg() will not block on this call whilst we're waiting.
(3) After dropping and regaining the call mutex, rxrpc_send_data() needs
to go and recheck the state of the tx_pending buffer and the
tx_total_len check in case we raced with another sendmsg() on the same
call.
Thinking on this some more, it might make sense to have different locks for
sendmsg() and recvmsg(). There's probably no need to make recvmsg() wait
for sendmsg(). It does mean that recvmsg() can return MSG_EOR indicating
that a call is dead before a sendmsg() to that call returns - but that can
currently happen anyway.
Without fix (2), something like the following can be induced:
WARNING: bad unlock balance detected!
5.16.0-rc6-syzkaller #0 Not tainted
-------------------------------------
syz-executor011/3597 is trying to release lock (&call->user_mutex) at:
[<ffffffff885163a3>] rxrpc_do_sendmsg+0xc13/0x1350 net/rxrpc/sendmsg.c:748
but there are no more locks to release!
other info that might help us debug this:
no locks held by syz-executor011/3597.
...
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_unlock_imbalance_bug include/trace/events/lock.h:58 [inline]
__lock_release kernel/locking/lockdep.c:5306 [inline]
lock_release.cold+0x49/0x4e kernel/locking/lockdep.c:5657
__mutex_unlock_slowpath+0x99/0x5e0 kernel/locking/mutex.c:900
rxrpc_do_sendmsg+0xc13/0x1350 net/rxrpc/sendmsg.c:748
rxrpc_sendmsg+0x420/0x630 net/rxrpc/af_rxrpc.c:561
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
___sys_sendmsg+0xf3/0x170 net/socket.c:2463
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
[Thanks to Hawkins Jiawei and Khalid Masum for their attempts to fix this] |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: Fix use-after-free of encap entry in neigh update handler
Function mlx5e_rep_neigh_update() wasn't updated to accommodate rtnl lock
removal from TC filter update path and properly handle concurrent encap
entry insertion/deletion which can lead to following use-after-free:
[23827.464923] ==================================================================
[23827.469446] BUG: KASAN: use-after-free in mlx5e_encap_take+0x72/0x140 [mlx5_core]
[23827.470971] Read of size 4 at addr ffff8881d132228c by task kworker/u20:6/21635
[23827.472251]
[23827.472615] CPU: 9 PID: 21635 Comm: kworker/u20:6 Not tainted 5.13.0-rc3+ #5
[23827.473788] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
[23827.475639] Workqueue: mlx5e mlx5e_rep_neigh_update [mlx5_core]
[23827.476731] Call Trace:
[23827.477260] dump_stack+0xbb/0x107
[23827.477906] print_address_description.constprop.0+0x18/0x140
[23827.478896] ? mlx5e_encap_take+0x72/0x140 [mlx5_core]
[23827.479879] ? mlx5e_encap_take+0x72/0x140 [mlx5_core]
[23827.480905] kasan_report.cold+0x7c/0xd8
[23827.481701] ? mlx5e_encap_take+0x72/0x140 [mlx5_core]
[23827.482744] kasan_check_range+0x145/0x1a0
[23827.493112] mlx5e_encap_take+0x72/0x140 [mlx5_core]
[23827.494054] ? mlx5e_tc_tun_encap_info_equal_generic+0x140/0x140 [mlx5_core]
[23827.495296] mlx5e_rep_neigh_update+0x41e/0x5e0 [mlx5_core]
[23827.496338] ? mlx5e_rep_neigh_entry_release+0xb80/0xb80 [mlx5_core]
[23827.497486] ? read_word_at_a_time+0xe/0x20
[23827.498250] ? strscpy+0xa0/0x2a0
[23827.498889] process_one_work+0x8ac/0x14e0
[23827.499638] ? lockdep_hardirqs_on_prepare+0x400/0x400
[23827.500537] ? pwq_dec_nr_in_flight+0x2c0/0x2c0
[23827.501359] ? rwlock_bug.part.0+0x90/0x90
[23827.502116] worker_thread+0x53b/0x1220
[23827.502831] ? process_one_work+0x14e0/0x14e0
[23827.503627] kthread+0x328/0x3f0
[23827.504254] ? _raw_spin_unlock_irq+0x24/0x40
[23827.505065] ? __kthread_bind_mask+0x90/0x90
[23827.505912] ret_from_fork+0x1f/0x30
[23827.506621]
[23827.506987] Allocated by task 28248:
[23827.507694] kasan_save_stack+0x1b/0x40
[23827.508476] __kasan_kmalloc+0x7c/0x90
[23827.509197] mlx5e_attach_encap+0xde1/0x1d40 [mlx5_core]
[23827.510194] mlx5e_tc_add_fdb_flow+0x397/0xc40 [mlx5_core]
[23827.511218] __mlx5e_add_fdb_flow+0x519/0xb30 [mlx5_core]
[23827.512234] mlx5e_configure_flower+0x191c/0x4870 [mlx5_core]
[23827.513298] tc_setup_cb_add+0x1d5/0x420
[23827.514023] fl_hw_replace_filter+0x382/0x6a0 [cls_flower]
[23827.514975] fl_change+0x2ceb/0x4a51 [cls_flower]
[23827.515821] tc_new_tfilter+0x89a/0x2070
[23827.516548] rtnetlink_rcv_msg+0x644/0x8c0
[23827.517300] netlink_rcv_skb+0x11d/0x340
[23827.518021] netlink_unicast+0x42b/0x700
[23827.518742] netlink_sendmsg+0x743/0xc20
[23827.519467] sock_sendmsg+0xb2/0xe0
[23827.520131] ____sys_sendmsg+0x590/0x770
[23827.520851] ___sys_sendmsg+0xd8/0x160
[23827.521552] __sys_sendmsg+0xb7/0x140
[23827.522238] do_syscall_64+0x3a/0x70
[23827.522907] entry_SYSCALL_64_after_hwframe+0x44/0xae
[23827.523797]
[23827.524163] Freed by task 25948:
[23827.524780] kasan_save_stack+0x1b/0x40
[23827.525488] kasan_set_track+0x1c/0x30
[23827.526187] kasan_set_free_info+0x20/0x30
[23827.526968] __kasan_slab_free+0xed/0x130
[23827.527709] slab_free_freelist_hook+0xcf/0x1d0
[23827.528528] kmem_cache_free_bulk+0x33a/0x6e0
[23827.529317] kfree_rcu_work+0x55f/0xb70
[23827.530024] process_one_work+0x8ac/0x14e0
[23827.530770] worker_thread+0x53b/0x1220
[23827.531480] kthread+0x328/0x3f0
[23827.532114] ret_from_fork+0x1f/0x30
[23827.532785]
[23827.533147] Last potentially related work creation:
[23827.534007] kasan_save_stack+0x1b/0x40
[23827.534710] kasan_record_aux_stack+0xab/0xc0
[23827.535492] kvfree_call_rcu+0x31/0x7b0
[23827.536206] mlx5e_tc_del
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Fix "KASAN: slab-use-after-free Read in ib_register_device" problem
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xc3/0x670 mm/kasan/report.c:521
kasan_report+0xe0/0x110 mm/kasan/report.c:634
strlen+0x93/0xa0 lib/string.c:420
__fortify_strlen include/linux/fortify-string.h:268 [inline]
get_kobj_path_length lib/kobject.c:118 [inline]
kobject_get_path+0x3f/0x2a0 lib/kobject.c:158
kobject_uevent_env+0x289/0x1870 lib/kobject_uevent.c:545
ib_register_device drivers/infiniband/core/device.c:1472 [inline]
ib_register_device+0x8cf/0xe00 drivers/infiniband/core/device.c:1393
rxe_register_device+0x275/0x320 drivers/infiniband/sw/rxe/rxe_verbs.c:1552
rxe_net_add+0x8e/0xe0 drivers/infiniband/sw/rxe/rxe_net.c:550
rxe_newlink+0x70/0x190 drivers/infiniband/sw/rxe/rxe.c:225
nldev_newlink+0x3a3/0x680 drivers/infiniband/core/nldev.c:1796
rdma_nl_rcv_msg+0x387/0x6e0 drivers/infiniband/core/netlink.c:195
rdma_nl_rcv_skb.constprop.0.isra.0+0x2e5/0x450
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg net/socket.c:727 [inline]
____sys_sendmsg+0xa95/0xc70 net/socket.c:2566
___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
__sys_sendmsg+0x16d/0x220 net/socket.c:2652
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
This problem is similar to the problem that the
commit 1d6a9e7449e2 ("RDMA/core: Fix use-after-free when rename device name")
fixes.
The root cause is: the function ib_device_rename() renames the name with
lock. But in the function kobject_uevent(), this name is accessed without
lock protection at the same time.
The solution is to add the lock protection when this name is accessed in
the function kobject_uevent(). |
| In the Linux kernel, the following vulnerability has been resolved:
ASoC: SOF: Intel: hda: Fix UAF when reloading module
hda_generic_machine_select() appends -idisp to the tplg filename by
allocating a new string with devm_kasprintf(), then stores the string
right back into the global variable snd_soc_acpi_intel_hda_machines.
When the module is unloaded, this memory is freed, resulting in a global
variable pointing to freed memory. Reloading the module then triggers
a use-after-free:
BUG: KFENCE: use-after-free read in string+0x48/0xe0
Use-after-free read at 0x00000000967e0109 (in kfence-#99):
string+0x48/0xe0
vsnprintf+0x329/0x6e0
devm_kvasprintf+0x54/0xb0
devm_kasprintf+0x58/0x80
hda_machine_select.cold+0x198/0x17a2 [snd_sof_intel_hda_generic]
sof_probe_work+0x7f/0x600 [snd_sof]
process_one_work+0x17b/0x330
worker_thread+0x2ce/0x3f0
kthread+0xcf/0x100
ret_from_fork+0x31/0x50
ret_from_fork_asm+0x1a/0x30
kfence-#99: 0x00000000198a940f-0x00000000ace47d9d, size=64, cache=kmalloc-64
allocated by task 333 on cpu 8 at 17.798069s (130.453553s ago):
devm_kmalloc+0x52/0x120
devm_kvasprintf+0x66/0xb0
devm_kasprintf+0x58/0x80
hda_machine_select.cold+0x198/0x17a2 [snd_sof_intel_hda_generic]
sof_probe_work+0x7f/0x600 [snd_sof]
process_one_work+0x17b/0x330
worker_thread+0x2ce/0x3f0
kthread+0xcf/0x100
ret_from_fork+0x31/0x50
ret_from_fork_asm+0x1a/0x30
freed by task 1543 on cpu 4 at 141.586686s (6.665010s ago):
release_nodes+0x43/0xb0
devres_release_all+0x90/0xf0
device_unbind_cleanup+0xe/0x70
device_release_driver_internal+0x1c1/0x200
driver_detach+0x48/0x90
bus_remove_driver+0x6d/0xf0
pci_unregister_driver+0x42/0xb0
__do_sys_delete_module+0x1d1/0x310
do_syscall_64+0x82/0x190
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Fix it by copying the match array with devm_kmemdup_array() before we
modify it. |
| In the Linux kernel, the following vulnerability has been resolved:
PCI: endpoint: pci-epf-test: Fix double free that causes kernel to oops
Fix a kernel oops found while testing the stm32_pcie Endpoint driver
with handling of PERST# deassertion:
During EP initialization, pci_epf_test_alloc_space() allocates all BARs,
which are further freed if epc_set_bar() fails (for instance, due to no
free inbound window).
However, when pci_epc_set_bar() fails, the error path:
pci_epc_set_bar() ->
pci_epf_free_space()
does not clear the previous assignment to epf_test->reg[bar].
Then, if the host reboots, the PERST# deassertion restarts the BAR
allocation sequence with the same allocation failure (no free inbound
window), creating a double free situation since epf_test->reg[bar] was
deallocated and is still non-NULL.
Thus, make sure that pci_epf_alloc_space() and pci_epf_free_space()
invocations are symmetric, and as such, set epf_test->reg[bar] to NULL
when memory is freed.
[kwilczynski: commit log] |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: SVM: Forcibly leave SMM mode on SHUTDOWN interception
Previously, commit ed129ec9057f ("KVM: x86: forcibly leave nested mode
on vCPU reset") addressed an issue where a triple fault occurring in
nested mode could lead to use-after-free scenarios. However, the commit
did not handle the analogous situation for System Management Mode (SMM).
This omission results in triggering a WARN when KVM forces a vCPU INIT
after SHUTDOWN interception while the vCPU is in SMM. This situation was
reprodused using Syzkaller by:
1) Creating a KVM VM and vCPU
2) Sending a KVM_SMI ioctl to explicitly enter SMM
3) Executing invalid instructions causing consecutive exceptions and
eventually a triple fault
The issue manifests as follows:
WARNING: CPU: 0 PID: 25506 at arch/x86/kvm/x86.c:12112
kvm_vcpu_reset+0x1d2/0x1530 arch/x86/kvm/x86.c:12112
Modules linked in:
CPU: 0 PID: 25506 Comm: syz-executor.0 Not tainted
6.1.130-syzkaller-00157-g164fe5dde9b6 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.12.0-1 04/01/2014
RIP: 0010:kvm_vcpu_reset+0x1d2/0x1530 arch/x86/kvm/x86.c:12112
Call Trace:
<TASK>
shutdown_interception+0x66/0xb0 arch/x86/kvm/svm/svm.c:2136
svm_invoke_exit_handler+0x110/0x530 arch/x86/kvm/svm/svm.c:3395
svm_handle_exit+0x424/0x920 arch/x86/kvm/svm/svm.c:3457
vcpu_enter_guest arch/x86/kvm/x86.c:10959 [inline]
vcpu_run+0x2c43/0x5a90 arch/x86/kvm/x86.c:11062
kvm_arch_vcpu_ioctl_run+0x50f/0x1cf0 arch/x86/kvm/x86.c:11283
kvm_vcpu_ioctl+0x570/0xf00 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4122
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl fs/ioctl.c:856 [inline]
__x64_sys_ioctl+0x19a/0x210 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Architecturally, INIT is blocked when the CPU is in SMM, hence KVM's WARN()
in kvm_vcpu_reset() to guard against KVM bugs, e.g. to detect improper
emulation of INIT. SHUTDOWN on SVM is a weird edge case where KVM needs to
do _something_ sane with the VMCB, since it's technically undefined, and
INIT is the least awful choice given KVM's ABI.
So, double down on stuffing INIT on SHUTDOWN, and force the vCPU out of
SMM to avoid any weirdness (and the WARN).
Found by Linux Verification Center (linuxtesting.org) with Syzkaller.
[sean: massage changelog, make it clear this isn't architectural behavior] |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: pn533: Fix use-after-free bugs caused by pn532_cmd_timeout
When the pn532 uart device is detaching, the pn532_uart_remove()
is called. But there are no functions in pn532_uart_remove() that
could delete the cmd_timeout timer, which will cause use-after-free
bugs. The process is shown below:
(thread 1) | (thread 2)
| pn532_uart_send_frame
pn532_uart_remove | mod_timer(&pn532->cmd_timeout,...)
... | (wait a time)
kfree(pn532) //FREE | pn532_cmd_timeout
| pn532_uart_send_frame
| pn532->... //USE
This patch adds del_timer_sync() in pn532_uart_remove() in order to
prevent the use-after-free bugs. What's more, the pn53x_unregister_nfc()
is well synchronized, it sets nfc_dev->shutting_down to true and there
are no syscalls could restart the cmd_timeout timer. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in smb_break_all_levII_oplock()
There is a room in smb_break_all_levII_oplock that can cause racy issues
when unlocking in the middle of the loop. This patch use read lock
to protect whole loop. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in __smb2_lease_break_noti()
Move tcp_transport free to ksmbd_conn_free. If ksmbd connection is
referenced when ksmbd server thread terminates, It will not be freed,
but conn->tcp_transport is freed. __smb2_lease_break_noti can be performed
asynchronously when the connection is disconnected. __smb2_lease_break_noti
calls ksmbd_conn_write, which can cause use-after-free
when conn->ksmbd_transport is already freed. |
| AUTOMGEN versions up to and including 8.0.0.7 (also referenced as 8.022) contain a vulnerability in that project file handling frees an object and subsequently dereferences the stale pointer when processing certain malformed fields. The dangling-pointer use enables an attacker to influence an indirect call through attacker-controlled memory, resulting in denial-of-service. In some conditions, remote code execution may be possible. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: flowtable: fix stuck flows on cleanup due to pending work
To clear the flow table on flow table free, the following sequence
normally happens in order:
1) gc_step work is stopped to disable any further stats/del requests.
2) All flow table entries are set to teardown state.
3) Run gc_step which will queue HW del work for each flow table entry.
4) Waiting for the above del work to finish (flush).
5) Run gc_step again, deleting all entries from the flow table.
6) Flow table is freed.
But if a flow table entry already has pending HW stats or HW add work
step 3 will not queue HW del work (it will be skipped), step 4 will wait
for the pending add/stats to finish, and step 5 will queue HW del work
which might execute after freeing of the flow table.
To fix the above, this patch flushes the pending work, then it sets the
teardown flag to all flows in the flowtable and it forces a garbage
collector run to queue work to remove the flows from hardware, then it
flushes this new pending work and (finally) it forces another garbage
collector run to remove the entry from the software flowtable.
Stack trace:
[47773.882335] BUG: KASAN: use-after-free in down_read+0x99/0x460
[47773.883634] Write of size 8 at addr ffff888103b45aa8 by task kworker/u20:6/543704
[47773.885634] CPU: 3 PID: 543704 Comm: kworker/u20:6 Not tainted 5.12.0-rc7+ #2
[47773.886745] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009)
[47773.888438] Workqueue: nf_ft_offload_del flow_offload_work_handler [nf_flow_table]
[47773.889727] Call Trace:
[47773.890214] dump_stack+0xbb/0x107
[47773.890818] print_address_description.constprop.0+0x18/0x140
[47773.892990] kasan_report.cold+0x7c/0xd8
[47773.894459] kasan_check_range+0x145/0x1a0
[47773.895174] down_read+0x99/0x460
[47773.899706] nf_flow_offload_tuple+0x24f/0x3c0 [nf_flow_table]
[47773.907137] flow_offload_work_handler+0x72d/0xbe0 [nf_flow_table]
[47773.913372] process_one_work+0x8ac/0x14e0
[47773.921325]
[47773.921325] Allocated by task 592159:
[47773.922031] kasan_save_stack+0x1b/0x40
[47773.922730] __kasan_kmalloc+0x7a/0x90
[47773.923411] tcf_ct_flow_table_get+0x3cb/0x1230 [act_ct]
[47773.924363] tcf_ct_init+0x71c/0x1156 [act_ct]
[47773.925207] tcf_action_init_1+0x45b/0x700
[47773.925987] tcf_action_init+0x453/0x6b0
[47773.926692] tcf_exts_validate+0x3d0/0x600
[47773.927419] fl_change+0x757/0x4a51 [cls_flower]
[47773.928227] tc_new_tfilter+0x89a/0x2070
[47773.936652]
[47773.936652] Freed by task 543704:
[47773.937303] kasan_save_stack+0x1b/0x40
[47773.938039] kasan_set_track+0x1c/0x30
[47773.938731] kasan_set_free_info+0x20/0x30
[47773.939467] __kasan_slab_free+0xe7/0x120
[47773.940194] slab_free_freelist_hook+0x86/0x190
[47773.941038] kfree+0xce/0x3a0
[47773.941644] tcf_ct_flow_table_cleanup_work
Original patch description and stack trace by Paul Blakey. |
