| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid use-after-free issue in f2fs_filemap_fault
syzbot reports a f2fs bug as below:
BUG: KASAN: slab-use-after-free in f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49
Read of size 8 at addr ffff88807bb22680 by task syz-executor184/5058
CPU: 0 PID: 5058 Comm: syz-executor184 Not tainted 6.7.0-syzkaller-09928-g052d534373b7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x163/0x540 mm/kasan/report.c:488
kasan_report+0x142/0x170 mm/kasan/report.c:601
f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49
__do_fault+0x131/0x450 mm/memory.c:4376
do_shared_fault mm/memory.c:4798 [inline]
do_fault mm/memory.c:4872 [inline]
do_pte_missing mm/memory.c:3745 [inline]
handle_pte_fault mm/memory.c:5144 [inline]
__handle_mm_fault+0x23b7/0x72b0 mm/memory.c:5285
handle_mm_fault+0x27e/0x770 mm/memory.c:5450
do_user_addr_fault arch/x86/mm/fault.c:1364 [inline]
handle_page_fault arch/x86/mm/fault.c:1507 [inline]
exc_page_fault+0x456/0x870 arch/x86/mm/fault.c:1563
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
The root cause is: in f2fs_filemap_fault(), vmf->vma may be not alive after
filemap_fault(), so it may cause use-after-free issue when accessing
vmf->vma->vm_flags in trace_f2fs_filemap_fault(). So it needs to keep vm_flags
in separated temporary variable for tracepoint use. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: rtl8xxxu: add cancel_work_sync() for c2hcmd_work
The workqueue might still be running, when the driver is stopped. To
avoid a use-after-free, call cancel_work_sync() in rtl8xxxu_stop(). |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: qat - resolve race condition during AER recovery
During the PCI AER system's error recovery process, the kernel driver
may encounter a race condition with freeing the reset_data structure's
memory. If the device restart will take more than 10 seconds the function
scheduling that restart will exit due to a timeout, and the reset_data
structure will be freed. However, this data structure is used for
completion notification after the restart is completed, which leads
to a UAF bug.
This results in a KFENCE bug notice.
BUG: KFENCE: use-after-free read in adf_device_reset_worker+0x38/0xa0 [intel_qat]
Use-after-free read at 0x00000000bc56fddf (in kfence-#142):
adf_device_reset_worker+0x38/0xa0 [intel_qat]
process_one_work+0x173/0x340
To resolve this race condition, the memory associated to the container
of the work_struct is freed on the worker if the timeout expired,
otherwise on the function that schedules the worker.
The timeout detection can be done by checking if the caller is
still waiting for completion or not by using completion_done() function. |
| In the Linux kernel, the following vulnerability has been resolved:
mac802154: fix llsec key resources release in mac802154_llsec_key_del
mac802154_llsec_key_del() can free resources of a key directly without
following the RCU rules for waiting before the end of a grace period. This
may lead to use-after-free in case llsec_lookup_key() is traversing the
list of keys in parallel with a key deletion:
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 4 PID: 16000 at lib/refcount.c:25 refcount_warn_saturate+0x162/0x2a0
Modules linked in:
CPU: 4 PID: 16000 Comm: wpan-ping Not tainted 6.7.0 #19
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:refcount_warn_saturate+0x162/0x2a0
Call Trace:
<TASK>
llsec_lookup_key.isra.0+0x890/0x9e0
mac802154_llsec_encrypt+0x30c/0x9c0
ieee802154_subif_start_xmit+0x24/0x1e0
dev_hard_start_xmit+0x13e/0x690
sch_direct_xmit+0x2ae/0xbc0
__dev_queue_xmit+0x11dd/0x3c20
dgram_sendmsg+0x90b/0xd60
__sys_sendto+0x466/0x4c0
__x64_sys_sendto+0xe0/0x1c0
do_syscall_64+0x45/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
Also, ieee802154_llsec_key_entry structures are not freed by
mac802154_llsec_key_del():
unreferenced object 0xffff8880613b6980 (size 64):
comm "iwpan", pid 2176, jiffies 4294761134 (age 60.475s)
hex dump (first 32 bytes):
78 0d 8f 18 80 88 ff ff 22 01 00 00 00 00 ad de x.......".......
00 00 00 00 00 00 00 00 03 00 cd ab 00 00 00 00 ................
backtrace:
[<ffffffff81dcfa62>] __kmem_cache_alloc_node+0x1e2/0x2d0
[<ffffffff81c43865>] kmalloc_trace+0x25/0xc0
[<ffffffff88968b09>] mac802154_llsec_key_add+0xac9/0xcf0
[<ffffffff8896e41a>] ieee802154_add_llsec_key+0x5a/0x80
[<ffffffff8892adc6>] nl802154_add_llsec_key+0x426/0x5b0
[<ffffffff86ff293e>] genl_family_rcv_msg_doit+0x1fe/0x2f0
[<ffffffff86ff46d1>] genl_rcv_msg+0x531/0x7d0
[<ffffffff86fee7a9>] netlink_rcv_skb+0x169/0x440
[<ffffffff86ff1d88>] genl_rcv+0x28/0x40
[<ffffffff86fec15c>] netlink_unicast+0x53c/0x820
[<ffffffff86fecd8b>] netlink_sendmsg+0x93b/0xe60
[<ffffffff86b91b35>] ____sys_sendmsg+0xac5/0xca0
[<ffffffff86b9c3dd>] ___sys_sendmsg+0x11d/0x1c0
[<ffffffff86b9c65a>] __sys_sendmsg+0xfa/0x1d0
[<ffffffff88eadbf5>] do_syscall_64+0x45/0xf0
[<ffffffff890000ea>] entry_SYSCALL_64_after_hwframe+0x6e/0x76
Handle the proper resource release in the RCU callback function
mac802154_llsec_key_del_rcu().
Note that if llsec_lookup_key() finds a key, it gets a refcount via
llsec_key_get() and locally copies key id from key_entry (which is a
list element). So it's safe to call llsec_key_put() and free the list
entry after the RCU grace period elapses.
Found by Linux Verification Center (linuxtesting.org). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/i915/vma: Fix UAF on destroy against retire race
Object debugging tools were sporadically reporting illegal attempts to
free a still active i915 VMA object when parking a GT believed to be idle.
[161.359441] ODEBUG: free active (active state 0) object: ffff88811643b958 object type: i915_active hint: __i915_vma_active+0x0/0x50 [i915]
[161.360082] WARNING: CPU: 5 PID: 276 at lib/debugobjects.c:514 debug_print_object+0x80/0xb0
...
[161.360304] CPU: 5 PID: 276 Comm: kworker/5:2 Not tainted 6.5.0-rc1-CI_DRM_13375-g003f860e5577+ #1
[161.360314] Hardware name: Intel Corporation Rocket Lake Client Platform/RocketLake S UDIMM 6L RVP, BIOS RKLSFWI1.R00.3173.A03.2204210138 04/21/2022
[161.360322] Workqueue: i915-unordered __intel_wakeref_put_work [i915]
[161.360592] RIP: 0010:debug_print_object+0x80/0xb0
...
[161.361347] debug_object_free+0xeb/0x110
[161.361362] i915_active_fini+0x14/0x130 [i915]
[161.361866] release_references+0xfe/0x1f0 [i915]
[161.362543] i915_vma_parked+0x1db/0x380 [i915]
[161.363129] __gt_park+0x121/0x230 [i915]
[161.363515] ____intel_wakeref_put_last+0x1f/0x70 [i915]
That has been tracked down to be happening when another thread is
deactivating the VMA inside __active_retire() helper, after the VMA's
active counter has been already decremented to 0, but before deactivation
of the VMA's object is reported to the object debugging tool.
We could prevent from that race by serializing i915_active_fini() with
__active_retire() via ref->tree_lock, but that wouldn't stop the VMA from
being used, e.g. from __i915_vma_retire() called at the end of
__active_retire(), after that VMA has been already freed by a concurrent
i915_vma_destroy() on return from the i915_active_fini(). Then, we should
rather fix the issue at the VMA level, not in i915_active.
Since __i915_vma_parked() is called from __gt_park() on last put of the
GT's wakeref, the issue could be addressed by holding the GT wakeref long
enough for __active_retire() to complete before that wakeref is released
and the GT parked.
I believe the issue was introduced by commit d93939730347 ("drm/i915:
Remove the vma refcount") which moved a call to i915_active_fini() from
a dropped i915_vma_release(), called on last put of the removed VMA kref,
to i915_vma_parked() processing path called on last put of a GT wakeref.
However, its visibility to the object debugging tool was suppressed by a
bug in i915_active that was fixed two weeks later with commit e92eb246feb9
("drm/i915/active: Fix missing debug object activation").
A VMA associated with a request doesn't acquire a GT wakeref by itself.
Instead, it depends on a wakeref held directly by the request's active
intel_context for a GT associated with its VM, and indirectly on that
intel_context's engine wakeref if the engine belongs to the same GT as the
VMA's VM. Those wakerefs are released asynchronously to VMA deactivation.
Fix the issue by getting a wakeref for the VMA's GT when activating it,
and putting that wakeref only after the VMA is deactivated. However,
exclude global GTT from that processing path, otherwise the GPU never goes
idle. Since __i915_vma_retire() may be called from atomic contexts, use
async variant of wakeref put. Also, to avoid circular locking dependency,
take care of acquiring the wakeref before VM mutex when both are needed.
v7: Add inline comments with justifications for:
- using untracked variants of intel_gt_pm_get/put() (Nirmoy),
- using async variant of _put(),
- not getting the wakeref in case of a global GTT,
- always getting the first wakeref outside vm->mutex.
v6: Since __i915_vma_active/retire() callbacks are not serialized, storing
a wakeref tracking handle inside struct i915_vma is not safe, and
there is no other good place for that. Use untracked variants of
intel_gt_pm_get/put_async().
v5: Replace "tile" with "GT" across commit description (Rodrigo),
-
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
soc: qcom: pmic_glink_altmode: fix drm bridge use-after-free
A recent DRM series purporting to simplify support for "transparent
bridges" and handling of probe deferrals ironically exposed a
use-after-free issue on pmic_glink_altmode probe deferral.
This has manifested itself as the display subsystem occasionally failing
to initialise and NULL-pointer dereferences during boot of machines like
the Lenovo ThinkPad X13s.
Specifically, the dp-hpd bridge is currently registered before all
resources have been acquired which means that it can also be
deregistered on probe deferrals.
In the meantime there is a race window where the new aux bridge driver
(or PHY driver previously) may have looked up the dp-hpd bridge and
stored a (non-reference-counted) pointer to the bridge which is about to
be deallocated.
When the display controller is later initialised, this triggers a
use-after-free when attaching the bridges:
dp -> aux -> dp-hpd (freed)
which may, for example, result in the freed bridge failing to attach:
[drm:drm_bridge_attach [drm]] *ERROR* failed to attach bridge /soc@0/phy@88eb000 to encoder TMDS-31: -16
or a NULL-pointer dereference:
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
...
Call trace:
drm_bridge_attach+0x70/0x1a8 [drm]
drm_aux_bridge_attach+0x24/0x38 [aux_bridge]
drm_bridge_attach+0x80/0x1a8 [drm]
dp_bridge_init+0xa8/0x15c [msm]
msm_dp_modeset_init+0x28/0xc4 [msm]
The DRM bridge implementation is clearly fragile and implicitly built on
the assumption that bridges may never go away. In this case, the fix is
to move the bridge registration in the pmic_glink_altmode driver to
after all resources have been looked up.
Incidentally, with the new dp-hpd bridge implementation, which registers
child devices, this is also a requirement due to a long-standing issue
in driver core that can otherwise lead to a probe deferral loop (see
commit fbc35b45f9f6 ("Add documentation on meaning of -EPROBE_DEFER")).
[DB: slightly fixed commit message by adding the word 'commit'] |
| In the Linux kernel, the following vulnerability has been resolved:
aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts
This patch is against CVE-2023-6270. The description of cve is:
A flaw was found in the ATA over Ethernet (AoE) driver in the Linux
kernel. The aoecmd_cfg_pkts() function improperly updates the refcnt on
`struct net_device`, and a use-after-free can be triggered by racing
between the free on the struct and the access through the `skbtxq`
global queue. This could lead to a denial of service condition or
potential code execution.
In aoecmd_cfg_pkts(), it always calls dev_put(ifp) when skb initial
code is finished. But the net_device ifp will still be used in
later tx()->dev_queue_xmit() in kthread. Which means that the
dev_put(ifp) should NOT be called in the success path of skb
initial code in aoecmd_cfg_pkts(). Otherwise tx() may run into
use-after-free because the net_device is freed.
This patch removed the dev_put(ifp) in the success path in
aoecmd_cfg_pkts(), and added dev_put() after skb xmit in tx(). |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/srpt: Do not register event handler until srpt device is fully setup
Upon rare occasions, KASAN reports a use-after-free Write
in srpt_refresh_port().
This seems to be because an event handler is registered before the
srpt device is fully setup and a race condition upon error may leave a
partially setup event handler in place.
Instead, only register the event handler after srpt device initialization
is complete. |
| In the Linux kernel, the following vulnerability has been resolved:
net: sparx5: Fix use after free inside sparx5_del_mact_entry
Based on the static analyzis of the code it looks like when an entry
from the MAC table was removed, the entry was still used after being
freed. More precise the vid of the mac_entry was used after calling
devm_kfree on the mac_entry.
The fix consists in first using the vid of the mac_entry to delete the
entry from the HW and after that to free it. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/irdma: Fix KASAN issue with tasklet
KASAN testing revealed the following issue assocated with freeing an IRQ.
[50006.466686] Call Trace:
[50006.466691] <IRQ>
[50006.489538] dump_stack+0x5c/0x80
[50006.493475] print_address_description.constprop.6+0x1a/0x150
[50006.499872] ? irdma_sc_process_ceq+0x483/0x790 [irdma]
[50006.505742] ? irdma_sc_process_ceq+0x483/0x790 [irdma]
[50006.511644] kasan_report.cold.11+0x7f/0x118
[50006.516572] ? irdma_sc_process_ceq+0x483/0x790 [irdma]
[50006.522473] irdma_sc_process_ceq+0x483/0x790 [irdma]
[50006.528232] irdma_process_ceq+0xb2/0x400 [irdma]
[50006.533601] ? irdma_hw_flush_wqes_callback+0x370/0x370 [irdma]
[50006.540298] irdma_ceq_dpc+0x44/0x100 [irdma]
[50006.545306] tasklet_action_common.isra.14+0x148/0x2c0
[50006.551096] __do_softirq+0x1d0/0xaf8
[50006.555396] irq_exit_rcu+0x219/0x260
[50006.559670] irq_exit+0xa/0x20
[50006.563320] smp_apic_timer_interrupt+0x1bf/0x690
[50006.568645] apic_timer_interrupt+0xf/0x20
[50006.573341] </IRQ>
The issue is that a tasklet could be pending on another core racing
the delete of the irq.
Fix by insuring any scheduled tasklet is killed after deleting the
irq. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_set_pipapo: release elements in clone only from destroy path
Clone already always provides a current view of the lookup table, use it
to destroy the set, otherwise it is possible to destroy elements twice.
This fix requires:
212ed75dc5fb ("netfilter: nf_tables: integrate pipapo into commit protocol")
which came after:
9827a0e6e23b ("netfilter: nft_set_pipapo: release elements in clone from abort path"). |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_chain_filter: handle NETDEV_UNREGISTER for inet/ingress basechain
Remove netdevice from inet/ingress basechain in case NETDEV_UNREGISTER
event is reported, otherwise a stale reference to netdevice remains in
the hook list. |
| In the Linux kernel, the following vulnerability has been resolved:
stmmac: Clear variable when destroying workqueue
Currently when suspending driver and stopping workqueue it is checked whether
workqueue is not NULL and if so, it is destroyed.
Function destroy_workqueue() does drain queue and does clear variable, but
it does not set workqueue variable to NULL. This can cause kernel/module
panic if code attempts to clear workqueue that was not initialized.
This scenario is possible when resuming suspended driver in stmmac_resume(),
because there is no handling for failed stmmac_hw_setup(),
which can fail and return if DMA engine has failed to initialize,
and workqueue is initialized after DMA engine.
Should DMA engine fail to initialize, resume will proceed normally,
but interface won't work and TX queue will eventually timeout,
causing 'Reset adapter' error.
This then does destroy workqueue during reset process.
And since workqueue is initialized after DMA engine and can be skipped,
it will cause kernel/module panic.
To secure against this possible crash, set workqueue variable to NULL when
destroying workqueue.
Log/backtrace from crash goes as follows:
[88.031977]------------[ cut here ]------------
[88.031985]NETDEV WATCHDOG: eth0 (sxgmac): transmit queue 1 timed out
[88.032017]WARNING: CPU: 0 PID: 0 at net/sched/sch_generic.c:477 dev_watchdog+0x390/0x398
<Skipping backtrace for watchdog timeout>
[88.032251]---[ end trace e70de432e4d5c2c0 ]---
[88.032282]sxgmac 16d88000.ethernet eth0: Reset adapter.
[88.036359]------------[ cut here ]------------
[88.036519]Call trace:
[88.036523] flush_workqueue+0x3e4/0x430
[88.036528] drain_workqueue+0xc4/0x160
[88.036533] destroy_workqueue+0x40/0x270
[88.036537] stmmac_fpe_stop_wq+0x4c/0x70
[88.036541] stmmac_release+0x278/0x280
[88.036546] __dev_close_many+0xcc/0x158
[88.036551] dev_close_many+0xbc/0x190
[88.036555] dev_close.part.0+0x70/0xc0
[88.036560] dev_close+0x24/0x30
[88.036564] stmmac_service_task+0x110/0x140
[88.036569] process_one_work+0x1d8/0x4a0
[88.036573] worker_thread+0x54/0x408
[88.036578] kthread+0x164/0x170
[88.036583] ret_from_fork+0x10/0x20
[88.036588]---[ end trace e70de432e4d5c2c1 ]---
[88.036597]Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: Avoid potential use-after-free in hci_error_reset
While handling the HCI_EV_HARDWARE_ERROR event, if the underlying
BT controller is not responding, the GPIO reset mechanism would
free the hci_dev and lead to a use-after-free in hci_error_reset.
Here's the call trace observed on a ChromeOS device with Intel AX201:
queue_work_on+0x3e/0x6c
__hci_cmd_sync_sk+0x2ee/0x4c0 [bluetooth <HASH:3b4a6>]
? init_wait_entry+0x31/0x31
__hci_cmd_sync+0x16/0x20 [bluetooth <HASH:3b4a 6>]
hci_error_reset+0x4f/0xa4 [bluetooth <HASH:3b4a 6>]
process_one_work+0x1d8/0x33f
worker_thread+0x21b/0x373
kthread+0x13a/0x152
? pr_cont_work+0x54/0x54
? kthread_blkcg+0x31/0x31
ret_from_fork+0x1f/0x30
This patch holds the reference count on the hci_dev while processing
a HCI_EV_HARDWARE_ERROR event to avoid potential crash. |
| In the Linux kernel, the following vulnerability has been resolved:
tls: fix use-after-free on failed backlog decryption
When the decrypt request goes to the backlog and crypto_aead_decrypt
returns -EBUSY, tls_do_decryption will wait until all async
decryptions have completed. If one of them fails, tls_do_decryption
will return -EBADMSG and tls_decrypt_sg jumps to the error path,
releasing all the pages. But the pages have been passed to the async
callback, and have already been released by tls_decrypt_done.
The only true async case is when crypto_aead_decrypt returns
-EINPROGRESS. With -EBUSY, we already waited so we can tell
tls_sw_recvmsg that the data is available for immediate copy, but we
need to notify tls_decrypt_sg (via the new ->async_done flag) that the
memory has already been released. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix racing between bpf_timer_cancel_and_free and bpf_timer_cancel
The following race is possible between bpf_timer_cancel_and_free
and bpf_timer_cancel. It will lead a UAF on the timer->timer.
bpf_timer_cancel();
spin_lock();
t = timer->time;
spin_unlock();
bpf_timer_cancel_and_free();
spin_lock();
t = timer->timer;
timer->timer = NULL;
spin_unlock();
hrtimer_cancel(&t->timer);
kfree(t);
/* UAF on t */
hrtimer_cancel(&t->timer);
In bpf_timer_cancel_and_free, this patch frees the timer->timer
after a rcu grace period. This requires a rcu_head addition
to the "struct bpf_hrtimer". Another kfree(t) happens in bpf_timer_init,
this does not need a kfree_rcu because it is still under the
spin_lock and timer->timer has not been visible by others yet.
In bpf_timer_cancel, rcu_read_lock() is added because this helper
can be used in a non rcu critical section context (e.g. from
a sleepable bpf prog). Other timer->timer usages in helpers.c
have been audited, bpf_timer_cancel() is the only place where
timer->timer is used outside of the spin_lock.
Another solution considered is to mark a t->flag in bpf_timer_cancel
and clear it after hrtimer_cancel() is done. In bpf_timer_cancel_and_free,
it busy waits for the flag to be cleared before kfree(t). This patch
goes with a straight forward solution and frees timer->timer after
a rcu grace period. |
| In the Linux kernel, the following vulnerability has been resolved:
devlink: fix possible use-after-free and memory leaks in devlink_init()
The pernet operations structure for the subsystem must be registered
before registering the generic netlink family.
Make an unregister in case of unsuccessful registration. |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: prevent use-after-free in encode_cap_msg()
In fs/ceph/caps.c, in encode_cap_msg(), "use after free" error was
caught by KASAN at this line - 'ceph_buffer_get(arg->xattr_buf);'. This
implies before the refcount could be increment here, it was freed.
In same file, in "handle_cap_grant()" refcount is decremented by this
line - 'ceph_buffer_put(ci->i_xattrs.blob);'. It appears that a race
occurred and resource was freed by the latter line before the former
line could increment it.
encode_cap_msg() is called by __send_cap() and __send_cap() is called by
ceph_check_caps() after calling __prep_cap(). __prep_cap() is where
arg->xattr_buf is assigned to ci->i_xattrs.blob. This is the spot where
the refcount must be increased to prevent "use after free" error. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: fix use-after-free bug
The bug can be triggered by sending a single amdgpu_gem_userptr_ioctl
to the AMDGPU DRM driver on any ASICs with an invalid address and size.
The bug was reported by Joonkyo Jung <[email protected]>.
For example the following code:
static void Syzkaller1(int fd)
{
struct drm_amdgpu_gem_userptr arg;
int ret;
arg.addr = 0xffffffffffff0000;
arg.size = 0x80000000; /*2 Gb*/
arg.flags = 0x7;
ret = drmIoctl(fd, 0xc1186451/*amdgpu_gem_userptr_ioctl*/, &arg);
}
Due to the address and size are not valid there is a failure in
amdgpu_hmm_register->mmu_interval_notifier_insert->__mmu_interval_notifier_insert->
check_shl_overflow, but we even the amdgpu_hmm_register failure we still call
amdgpu_hmm_unregister into amdgpu_gem_object_free which causes access to a bad address.
The following stack is below when the issue is reproduced when Kazan is enabled:
[ +0.000014] Hardware name: ASUS System Product Name/ROG STRIX B550-F GAMING (WI-FI), BIOS 1401 12/03/2020
[ +0.000009] RIP: 0010:mmu_interval_notifier_remove+0x327/0x340
[ +0.000017] Code: ff ff 49 89 44 24 08 48 b8 00 01 00 00 00 00 ad de 4c 89 f7 49 89 47 40 48 83 c0 22 49 89 47 48 e8 ce d1 2d 01 e9 32 ff ff ff <0f> 0b e9 16 ff ff ff 4c 89 ef e8 fa 14 b3 ff e9 36 ff ff ff e8 80
[ +0.000014] RSP: 0018:ffffc90002657988 EFLAGS: 00010246
[ +0.000013] RAX: 0000000000000000 RBX: 1ffff920004caf35 RCX: ffffffff8160565b
[ +0.000011] RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff8881a9f78260
[ +0.000010] RBP: ffffc90002657a70 R08: 0000000000000001 R09: fffff520004caf25
[ +0.000010] R10: 0000000000000003 R11: ffffffff8161d1d6 R12: ffff88810e988c00
[ +0.000010] R13: ffff888126fb5a00 R14: ffff88810e988c0c R15: ffff8881a9f78260
[ +0.000011] FS: 00007ff9ec848540(0000) GS:ffff8883cc880000(0000) knlGS:0000000000000000
[ +0.000012] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ +0.000010] CR2: 000055b3f7e14328 CR3: 00000001b5770000 CR4: 0000000000350ef0
[ +0.000010] Call Trace:
[ +0.000006] <TASK>
[ +0.000007] ? show_regs+0x6a/0x80
[ +0.000018] ? __warn+0xa5/0x1b0
[ +0.000019] ? mmu_interval_notifier_remove+0x327/0x340
[ +0.000018] ? report_bug+0x24a/0x290
[ +0.000022] ? handle_bug+0x46/0x90
[ +0.000015] ? exc_invalid_op+0x19/0x50
[ +0.000016] ? asm_exc_invalid_op+0x1b/0x20
[ +0.000017] ? kasan_save_stack+0x26/0x50
[ +0.000017] ? mmu_interval_notifier_remove+0x23b/0x340
[ +0.000019] ? mmu_interval_notifier_remove+0x327/0x340
[ +0.000019] ? mmu_interval_notifier_remove+0x23b/0x340
[ +0.000020] ? __pfx_mmu_interval_notifier_remove+0x10/0x10
[ +0.000017] ? kasan_save_alloc_info+0x1e/0x30
[ +0.000018] ? srso_return_thunk+0x5/0x5f
[ +0.000014] ? __kasan_kmalloc+0xb1/0xc0
[ +0.000018] ? srso_return_thunk+0x5/0x5f
[ +0.000013] ? __kasan_check_read+0x11/0x20
[ +0.000020] amdgpu_hmm_unregister+0x34/0x50 [amdgpu]
[ +0.004695] amdgpu_gem_object_free+0x66/0xa0 [amdgpu]
[ +0.004534] ? __pfx_amdgpu_gem_object_free+0x10/0x10 [amdgpu]
[ +0.004291] ? do_syscall_64+0x5f/0xe0
[ +0.000023] ? srso_return_thunk+0x5/0x5f
[ +0.000017] drm_gem_object_free+0x3b/0x50 [drm]
[ +0.000489] amdgpu_gem_userptr_ioctl+0x306/0x500 [amdgpu]
[ +0.004295] ? __pfx_amdgpu_gem_userptr_ioctl+0x10/0x10 [amdgpu]
[ +0.004270] ? srso_return_thunk+0x5/0x5f
[ +0.000014] ? __this_cpu_preempt_check+0x13/0x20
[ +0.000015] ? srso_return_thunk+0x5/0x5f
[ +0.000013] ? sysvec_apic_timer_interrupt+0x57/0xc0
[ +0.000020] ? srso_return_thunk+0x5/0x5f
[ +0.000014] ? asm_sysvec_apic_timer_interrupt+0x1b/0x20
[ +0.000022] ? drm_ioctl_kernel+0x17b/0x1f0 [drm]
[ +0.000496] ? __pfx_amdgpu_gem_userptr_ioctl+0x10/0x10 [amdgpu]
[ +0.004272] ? drm_ioctl_kernel+0x190/0x1f0 [drm]
[ +0.000492] drm_ioctl_kernel+0x140/0x1f0 [drm]
[ +0.000497] ? __pfx_amdgpu_gem_userptr_ioctl+0x10/0x10 [amdgpu]
[ +0.004297] ? __pfx_drm_ioctl_kernel+0x10/0x10 [d
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: sh: aica: reorder cleanup operations to avoid UAF bugs
The dreamcastcard->timer could schedule the spu_dma_work and the
spu_dma_work could also arm the dreamcastcard->timer.
When the snd_pcm_substream is closing, the aica_channel will be
deallocated. But it could still be dereferenced in the worker
thread. The reason is that del_timer() will return directly
regardless of whether the timer handler is running or not and
the worker could be rescheduled in the timer handler. As a result,
the UAF bug will happen. The racy situation is shown below:
(Thread 1) | (Thread 2)
snd_aicapcm_pcm_close() |
... | run_spu_dma() //worker
| mod_timer()
flush_work() |
del_timer() | aica_period_elapsed() //timer
kfree(dreamcastcard->channel) | schedule_work()
| run_spu_dma() //worker
... | dreamcastcard->channel-> //USE
In order to mitigate this bug and other possible corner cases,
call mod_timer() conditionally in run_spu_dma(), then implement
PCM sync_stop op to cancel both the timer and worker. The sync_stop
op will be called from PCM core appropriately when needed. |
