| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| Use after free in Microsoft Office Click-To-Run allows an authorized attacker to elevate privileges locally. |
| Use after free in Microsoft Office PowerPoint allows an unauthorized attacker to execute code over a network. |
| A security vulnerability has been detected in GPAC up to 26.07.0. The impacted element is the function gf_mx_v of the file utils/os_thread.c of the component MP4Box. Such manipulation leads to use after free. The attack can be launched remotely. The exploit has been disclosed publicly and may be used. The vendor was contacted early about this disclosure but did not respond in any way. |
| Use after free in Remote Desktop Client allows an unauthorized attacker to execute code over a network. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/resctrl: Fix UAF from worker threads when domains are removed
The mbm_handle_overflow() and cqm_handle_limbo() workers read event counters
and may sleep while doing so. They are scheduled via delayed_work embedded in
struct rdt_l3_mon_domain. Architecture allocates and frees these domains from
CPU hotplug callbacks under cpus_write_lock(), and the workers acquire
cpus_read_lock() to keep the domain alive across their access.
A use-after-free can occur when a worker is blocked waiting for
cpus_read_lock() while the hotplug core holds cpus_write_lock(): the
architecture frees the rdt_l3_mon_domain that contains the worker's
work_struct. When the worker unblocks, the container_of() it performs on the
embedded work pointer dereferences freed memory.
Drop cpus_read_lock() from the workers and instead drain pending and in-flight
work synchronously before the architecture can free the domain. Since
architecture offlines the domain under cpus_write_lock() after it has been
unlinked from the RCU list and a grace period has elapsed, no new work can be
scheduled. The cancel only needs to wait out existing work. Drop
rdtgroup_mutex during CPU offline around cancel_delayed_work_sync() so that
a worker waiting on the mutex can complete before re-pinning the work on
a different CPU.
When offlining a CPU the architecture may iterate over resources in any order.
For example, the MBA control domain may be offlined before or after
a corresponding L3 monitor domain. Ensure that resctrl fs cancels the workers
no matter what order the architecture offlines the domains. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mt76: mt792x: fix use-after-free in mt76_rx_poll_complete
A use-after-free issue occurs in mt76_rx_poll_complete due to a race
condition. The STA has already been removed, but the rx_status still
had a pointer to the wcid in the STA.
Set the links' wcid pointers to be NULL for a MLD in
mt7925_sta_pre_rcu_remove()
BUG: KASAN: invalid-access in mt76_rx_poll_complete+0x280/0x470
Call trace:
dump_backtrace+0xec/0x128
show_stack+0x18/0x28
dump_stack_lvl+0x40/0xc8
print_report+0x1b8/0x710
kasan_report+0xe0/0x144
do_bad_area+0x120/0x260
do_tag_check_fault+0x20/0x34
do_mem_abort+0x54/0xa8
el1_abort+0x3c/0x5c
el1h_64_sync_handler+0x40/0xcc
el1h_64_sync+0x7c/0x80
mt76_rx_poll_complete+0x280/0x470
mt76_dma_rx_poll+0x114/0x51c
mt792x_poll_rx+0x60/0xf8
napi_threaded_poll_loop+0xe0/0x450
napi_threaded_poll+0x80/0x9c
kthread+0x11c/0x158
ret_from_fork+0x10/0x20 |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Invalidate RCU pointers after final spin unlock
In a sleepable BPF program, a spin lock can provide the only RCU protection
for a kptr. The final bpf_spin_unlock() ends that protection, but the
verifier leaves the pointer valid. Another CPU can then free the object
before the pointer is used. A capability-limited runtime PoC triggered a
task_struct use-after-free in __bpf_get_task_stack().
Record whether the program is in an RCU-protected context before releasing
the lock. Invalidate RCU-protected pointers only when the unlock leaves the
final such context. This preserves valid pointers in non-sleepable programs
and inside an explicit RCU read-side section. |
| In the Linux kernel, the following vulnerability has been resolved:
irqchip/gic-v5: Clear per-CPU IRS data on teardown
IRS affinity setup publishes an IRS pointer and IAFFID state in the
per-CPU data before the remaining IRS initialization can fail. The
error path then frees the IRS data without clearing that published
state, leaving CPUs associated with freed memory.
On initialization failure and normal IRS teardown, clear the per-CPU
IRS association by removing the stale pointer to irs_data. Also
invalidate the per-CPU IAFFID state for any CPUs that were tied to the
IRS before it was freed. |
| In the Linux kernel, the following vulnerability has been resolved:
octeontx2-af: fix cn20k mailbox lifetime on repeated rvu_mbox_init()
rvu_mbox_init() is called separately for AF-PF mailboxes during probe
and for AF-VF mailboxes when SR-IOV is enabled. Each call used to
allocate a new ng_rvu object, leaking the first allocation when the
pointer was overwritten on the second call.
Sharing one ng_rvu across both paths exposed several teardown bugs:
the error path freed all cn20k mailbox DMA and kfree()d ng_rvu even
when only the failing init type should be unwound, leaving live AF-PF
mailbox memory in use after an AF-VF init failure. mutex_init() was
also re-run on the AF-VF path while AF-PF mailbox handlers could still
hold rvu->mbox_lock. Probe and SR-IOV failure paths did not release
cn20k mailbox DMA either, since cleanup only happened in rvu_remove().
Allocate ng_rvu once with devm_kzalloc(), initialize mbox_lock in the
same block, unwind only the mailbox memory for the failing init type,
and free cn20k mailbox DMA from the probe and pci_enable_sriov()
error paths. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: SEV: Forcefully invalidate SNP VMSA if its backing gmem page is zapped
Wire up a gmem_invalidate_range() call for SNP VMs, and use it to force
vCPUs to reload/recheck their guest-provided VMSA if the backing gmem
page is being invalidated, e.g. is being PUNCH_HOLE'd. Use the same core
logic to handle invalidations as VMX does for the APIC-access page, as the
two concepts are nearly identical: shove the physical address of a page
into the vCPU's control structure:
1. Snapshot the invalidation sequence counter
2. Grab the pfn (from guest_memfd in this case)
3. Acquire mmu_lock for read
4. Re-request reload if retry is needed, otherwise commit the change.
Note, the re-request action in #4 is necessary as KVM's retry logic is
fuzzy, i.e. can get false positives. If the guest_memfd page has been
dropped, at some point a subsequent reload will fail to get a PFN from
guest_memfd, and KVM will fail KVM_RUN. If the retry was due to a false
positive, KVM will retry until there are no relevant MMU notifier events
(and will retry in the "outer" loop, i.e. will drop locks and resched as
needed).
Note #2! Take care to invalidate the VMSA when a relevant memslot is
DELETED or MOVED, as invalidations in response to PUNCH_HOLE are predicated
on memslot bindings (KVM doesn't know what GFN range(s) to invalidate
without a binding). And more importantly, the VMSA mapping requires a
memslot, i.e. must be invalidated if its memslots disappears, regardless of
the state of the underlying guest_memfd inode.
Failure to invalidate the vCPU's control.vmsa_pa (which is checked by
pre_sev_run()) can prevent KVM from properly freeing the page as firmware
will reject the RMPUPDATE to reclaim the page with FAIL_INUSE if the vCPU
is actively running, i.e. if VMSA page is in-use. That in turn leads to an
RMP #PF on the next use, as the page will still be assigned to the SNP VM.
SEV-SNP: RMPUPDATE failed for PFN 78d198, pg_level: 1, ret: 3
SEV-SNP: PFN 0x78d198, RMP entry: [0xfff0000000144001 - 0x000000000000000f]
CPU: 3 UID: 0 PID: 31345 Comm: sev_snp_vmsa_pu Tainted: G U O
Tainted: [U]=USER, [O]=OOT_MODULE
Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.86.0-102 01/25/2026
Call Trace:
<TASK>
dump_stack_lvl+0x54/0x70
rmpupdate+0x12c/0x140
rmp_make_shared+0x3b/0x60
sev_gmem_invalidate+0xe0/0x170 [kvm_amd]
delete_from_page_cache_batch+0x1d8/0x220
truncate_inode_pages_range+0x120/0x3d0
kvm_gmem_fallocate+0x19a/0x270 [kvm]
vfs_fallocate+0x1bc/0x1f0
__x64_sys_fallocate+0x48/0x70
do_syscall_64+0x10a/0x480
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x496c7e
</TASK>
------------[ cut here ]------------
SEV: Failed to update RMP entry for PFN 0x78d198 error -14
WARNING: arch/x86/kvm/svm/sev.c:5160 at sev_gmem_invalidate+0x126/0x170 [kvm_amd], CPU#3: sev_snp_vmsa_pu/31345
CPU: 3 UID: 0 PID: 31345 Comm: sev_snp_vmsa_pu Tainted: G U O
Tainted: [U]=USER, [O]=OOT_MODULE
Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 34.86.0-102 01/25/2026
RIP: 0010:sev_gmem_invalidate+0x12b/0x170 [kvm_amd]
Call Trace:
<TASK>
delete_from_page_cache_batch+0x1d8/0x220
truncate_inode_pages_range+0x120/0x3d0
kvm_gmem_fallocate+0x19a/0x270 [kvm]
vfs_fallocate+0x1bc/0x1f0
__x64_sys_fallocate+0x48/0x70
do_syscall_64+0x10a/0x480
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x496c7e
</TASK>
irq event stamp: 20689
hardirqs last enabled at (20699): [<ffffffff8e76092c>] __console_unlock+0x5c/0x60
hardirqs last disabled at (20708): [<ffffffff8e760911>] __console_unlock+0x41/0x60
softirqs last enabled at (20722): [<ffffffff8e6cd74e>] __irq_exit_rcu+0x7e/0x140
softirqs last disabled at (20717): [<ffffffff8e6cd74e>] __irq_exit_rcu+0x7e/0x140
---[ end trace 0000000000000000 ]---
BUG: unable to handle page fault for address: ffff99
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
media: iris: fix use-after-free of fmt_src during MBPF check
During concurrency testing, multiple instances can run in parallel, and
each instance uses its own inst->lock while the core->lock protects the
list of active instances. The race happens because these locks cover
different scopes, inst->lock protects only the internals of a single
instance, while the Macro Blocks Per Frame (MBPF) checker walks the
core list under core->lock and reads fields like fmt_src->width and
fmt_src->height. At the same time, iris_close() may free fmt_src and
fmt_dst under inst->lock while the instance is still present in the core
list. This allows a situation where the MBPF checker, still iterating
through the core list, reaches an instance whose fmt_src was already
freed by another thread and ends up dereferencing a dangling pointer,
resulting in a use-after-free. This happens because the MBPF checker
assumes that any instance in the core list is fully valid, but the
freeing of fmt_src and fmt_dst without removing the instance from the
core list is not correct.
The correct ordering is to defer freeing fmt_src and fmt_dst until after
the instance has been removed from the core list and all teardown under
the core lock has completed, ensuring that no dangling pointers are ever
exposed during MBPF checks. |
| In the Linux kernel, the following vulnerability has been resolved:
net: ti: icssg-prueth: fix use-after-free of CPPI descriptor in RX path
cppi5_hdesc_get_psdata() returns a pointer into the CPPI descriptor.
In both emac_rx_packet() and emac_rx_packet_zc(), the descriptor is
freed via k3_cppi_desc_pool_free() before the psdata pointer is used
by emac_rx_timestamp(), which dereferences psdata[0] and psdata[1].
This constitutes a use-after-free on every received packet that goes
through the timestamp path.
Defer the descriptor free until after all accesses through the psdata
pointer are complete. For emac_rx_packet(), move the free into the
requeue label so both early-exit and success paths free the descriptor
after all accesses are done. For emac_rx_packet_zc(), move the free to
the end of the loop body after emac_dispatch_skb_zc() (which calls
emac_rx_timestamp()) has returned. |
| Use-after-free in the XML component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5. |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: act_api: use RCU with deferred freeing for action lifecycle
When NEWTFILTER and DELFILTER are run concurrently it is possible to create a
race with an associated action.
Let's illustrate with CPU0 running NEWTFILTER and CPU1 running DELFILTER:
0: mutex_lock() <-- holds the idr lock
0: rcu_read_lock()
0: p = idr_find(idr, index) <-- action p is valid (RCU protects IDR)
0: mutex_unlock() <-- releases the idr lock
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index) <-- Action removed from IDR
1: mutex_unlock() <-- mutex released allowing us to delete the action
1: tcf_action_cleanup(p); kfree(p) <-- Kfrees p immediately, no deferral
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- ouch, UAF p points to freed memory
This patch fixes the race condition between NEWTFILTER and DELFILTER by
adding struct rcu_head to tc_action used in the deferral and introducing a
call_rcu() in the delete path to defer the final kfree().
Note: this is a revert of commit d7fb60b9cafb ("net_sched: get rid of tcfa_rcu")
but also modernization/simplification to directly use kfree_rcu().
Let's illustrate the new restored code path:
0: rcu_read_lock()
1: refcount_dec_and_mutex_lock() <-- refcnt 1->0, mutex held
1: idr_remove(idr, index)
1: mutex_unlock()
1: call_rcu(&p->tcfa_rcu, tcf_action_rcu_free) <-- defer kfree after grace period
0: p = idr_find(idr, index)
0: refcount_inc_not_zero(&p->tcfa_refcnt) <-- fails, refcnt already 0
1: rcu_read_unlock() <-- release so freeing can run after grace period
After CPU1 calls idr_remove(), the object is no longer reachable through the IDR.
CPU0's subsequent idr_find() will return NULL, and even if it still held a
stale pointer, the immediate kfree() is now deferred until after the RCU grace
period, so no UAF can occur. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: RFCOMM: hold listener socket in rfcomm_connect_ind()
rfcomm_get_sock_by_channel() scans rfcomm_sk_list under the list lock,
but returns the selected listener after dropping that lock without
taking a reference. rfcomm_connect_ind() then locks the listener,
queues a child socket on it, and may notify it after unlocking it.
The buggy scenario involves two paths, with each column showing the
order within that path:
rfcomm_connect_ind(): listener close:
1. Find parent in 1. close() enters
rfcomm_get_sock_by_channel() rfcomm_sock_release().
2. Drop rfcomm_sk_list.lock 2. rfcomm_sock_shutdown()
without pinning parent. closes the listener.
3. Call lock_sock(parent) and 3. rfcomm_sock_kill()
bt_accept_enqueue(parent, unlinks and puts parent.
sk, true).
4. Read parent flags and may 4. parent can be freed.
call sk_state_change().
If close wins the race, parent can be freed before
rfcomm_connect_ind() reaches lock_sock(), bt_accept_enqueue(), or the
deferred-setup callback.
Take a reference on the listener before leaving rfcomm_sk_list.lock.
After lock_sock() succeeds, recheck that it is still in BT_LISTEN
before queueing a child, cache the deferred-setup bit while the parent
is locked, and drop the reference after the last parent use.
KASAN reported a slab-use-after-free in lock_sock_nested() from
rfcomm_connect_ind(), with the freeing stack going through
rfcomm_sock_kill() and rfcomm_sock_release(). |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free of a deferred file_lock on double SMB2_CANCEL
A deferred byte-range lock (an SMB2_LOCK that blocks) registers an async work on
conn->async_requests via setup_async_work(), with cancel_fn =
smb2_remove_blocked_lock and cancel_argv[0] pointing at the struct file_lock.
When the request is cancelled, the worker frees the file_lock with
locks_free_lock() and takes the cancelled early-exit, which "goto out"s and never
reaches release_async_work() -- the only site that unlinks the work from
conn->async_requests and clears cancel_fn/cancel_argv. The work therefore stays
matchable on async_requests with a live cancel_fn pointing at the freed file_lock,
until connection teardown finally runs release_async_work().
smb2_cancel() fires cancel_fn unconditionally with no state guard, so a second
SMB2_CANCEL for the same AsyncId, arriving in that window, re-runs
smb2_remove_blocked_lock() on the freed file_lock -- a slab use-after-free:
BUG: KASAN: slab-use-after-free in __locks_delete_block
__locks_delete_block
locks_delete_block
ksmbd_vfs_posix_lock_unblock
smb2_remove_blocked_lock
smb2_cancel <- 2nd SMB2_CANCEL fires cancel_fn
handle_ksmbd_work
Allocated by ...: locks_alloc_lock <- smb2_lock
Freed by ...: locks_free_lock <- smb2_lock (cancelled branch)
... cache file_lock_cache of size 192
Reproduced on mainline with KASAN by an authenticated SMB client.
Skip a work whose state is already KSMBD_WORK_CANCELLED so its cancel callback
cannot be fired a second time. |
| In the Linux kernel, the following vulnerability has been resolved:
rtmutex: Use waiter::task instead of current in remove_waiter()
remove_waiter() is used by the slowlock paths, but it is also used for
proxy-lock rollback in rt_mutex_start_proxy_lock() when invoked from
futex_requeue().
In the latter case waiter::task is not current, but remove_waiter()
operates on current for the dequeue operation. That results in several
problems:
1) the rbtree dequeue happens without waiter::task::pi_lock being held
2) the waiter task's pi_blocked_on state is not cleared, which leaves a
dangling pointer primed for UAF around.
3) rt_mutex_adjust_prio_chain() operates on the wrong top priority waiter
task
Use waiter::task instead of current in all related operations in
remove_waiter() to cure those problems.
[ tglx: Fixup rt_mutex_adjust_prio_chain(), add a comment and amend the
changelog ] |
| In the Linux kernel, the following vulnerability has been resolved:
net: macb: fix use-after-free access to PTP clock
PTP clock is registered on every opening of the interface and destroyed on
every closing. However it may be accessed via get_ts_info ethtool call
which is possible while the interface is just present in the kernel.
BUG: KASAN: use-after-free in ptp_clock_index+0x47/0x50 drivers/ptp/ptp_clock.c:426
Read of size 4 at addr ffff8880194345cc by task syz.0.6/948
CPU: 1 PID: 948 Comm: syz.0.6 Not tainted 6.1.164+ #109
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.1-0-g3208b098f51a-prebuilt.qemu.org 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x8d/0xba lib/dump_stack.c:106
print_address_description mm/kasan/report.c:316 [inline]
print_report+0x17f/0x496 mm/kasan/report.c:420
kasan_report+0xd9/0x180 mm/kasan/report.c:524
ptp_clock_index+0x47/0x50 drivers/ptp/ptp_clock.c:426
gem_get_ts_info+0x138/0x1e0 drivers/net/ethernet/cadence/macb_main.c:3349
macb_get_ts_info+0x68/0xb0 drivers/net/ethernet/cadence/macb_main.c:3371
__ethtool_get_ts_info+0x17c/0x260 net/ethtool/common.c:558
ethtool_get_ts_info net/ethtool/ioctl.c:2367 [inline]
__dev_ethtool net/ethtool/ioctl.c:3017 [inline]
dev_ethtool+0x2b05/0x6290 net/ethtool/ioctl.c:3095
dev_ioctl+0x637/0x1070 net/core/dev_ioctl.c:510
sock_do_ioctl+0x20d/0x2c0 net/socket.c:1215
sock_ioctl+0x577/0x6d0 net/socket.c:1320
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+0x18c/0x210 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
</TASK>
Allocated by task 457:
kmalloc include/linux/slab.h:563 [inline]
kzalloc include/linux/slab.h:699 [inline]
ptp_clock_register+0x144/0x10e0 drivers/ptp/ptp_clock.c:235
gem_ptp_init+0x46f/0x930 drivers/net/ethernet/cadence/macb_ptp.c:375
macb_open+0x901/0xd10 drivers/net/ethernet/cadence/macb_main.c:2920
__dev_open+0x2ce/0x500 net/core/dev.c:1501
__dev_change_flags+0x56a/0x740 net/core/dev.c:8651
dev_change_flags+0x92/0x170 net/core/dev.c:8722
do_setlink+0xaf8/0x3a80 net/core/rtnetlink.c:2833
__rtnl_newlink+0xbf4/0x1940 net/core/rtnetlink.c:3608
rtnl_newlink+0x63/0xa0 net/core/rtnetlink.c:3655
rtnetlink_rcv_msg+0x3c6/0xed0 net/core/rtnetlink.c:6150
netlink_rcv_skb+0x15d/0x430 net/netlink/af_netlink.c:2511
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0x6d7/0xa30 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x97e/0xeb0 net/netlink/af_netlink.c:1872
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg+0x14b/0x180 net/socket.c:730
__sys_sendto+0x320/0x3b0 net/socket.c:2152
__do_sys_sendto net/socket.c:2164 [inline]
__se_sys_sendto net/socket.c:2160 [inline]
__x64_sys_sendto+0xdc/0x1b0 net/socket.c:2160
do_syscall_x64 arch/x86/entry/common.c:46 [inline]
do_syscall_64+0x35/0x80 arch/x86/entry/common.c:76
entry_SYSCALL_64_after_hwframe+0x6e/0xd8
Freed by task 938:
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1729 [inline]
slab_free_freelist_hook mm/slub.c:1755 [inline]
slab_free mm/slub.c:3687 [inline]
__kmem_cache_free+0xbc/0x320 mm/slub.c:3700
device_release+0xa0/0x240 drivers/base/core.c:2507
kobject_cleanup lib/kobject.c:681 [inline]
kobject_release lib/kobject.c:712 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x1cd/0x350 lib/kobject.c:729
put_device+0x1b/0x30 drivers/base/core.c:3805
ptp_clock_unregister+0x171/0x270 drivers/ptp/ptp_clock.c:391
gem_ptp_remove+0x4e/0x1f0 drivers/net/ethernet/cadence/macb_ptp.c:404
macb_close+0x1c8/0x270 drivers/net/ethernet/cadence/macb_main.c:2966
__dev_close_many+0x1b9/0x310 net/core/dev.c:1585
__dev_close net/core/dev.c:1597 [inline]
__dev_change_flags+0x2bb/0x740 net/core/dev.c:8649
dev_change_fl
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix a UAF issue in bpf_trampoline_link_cgroup_shim
The root cause of this bug is that when 'bpf_link_put' reduces the
refcount of 'shim_link->link.link' to zero, the resource is considered
released but may still be referenced via 'tr->progs_hlist' in
'cgroup_shim_find'. The actual cleanup of 'tr->progs_hlist' in
'bpf_shim_tramp_link_release' is deferred. During this window, another
process can cause a use-after-free via 'bpf_trampoline_link_cgroup_shim'.
Based on Martin KaFai Lau's suggestions, I have created a simple patch.
To fix this:
Add an atomic non-zero check in 'bpf_trampoline_link_cgroup_shim'.
Only increment the refcount if it is not already zero.
Testing:
I verified the fix by adding a delay in
'bpf_shim_tramp_link_release' to make the bug easier to trigger:
static void bpf_shim_tramp_link_release(struct bpf_link *link)
{
/* ... */
if (!shim_link->trampoline)
return;
+ msleep(100);
WARN_ON_ONCE(bpf_trampoline_unlink_prog(&shim_link->link,
shim_link->trampoline, NULL));
bpf_trampoline_put(shim_link->trampoline);
}
Before the patch, running a PoC easily reproduced the crash(almost 100%)
with a call trace similar to KaiyanM's report.
After the patch, the bug no longer occurs even after millions of
iterations. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: libertas: fix use-after-free in lbs_free_adapter()
The lbs_free_adapter() function uses timer_delete() (non-synchronous)
for both command_timer and tx_lockup_timer before the structure is
freed. This is incorrect because timer_delete() does not wait for
any running timer callback to complete.
If a timer callback is executing when lbs_free_adapter() is called,
the callback will access freed memory since lbs_cfg_free() frees the
containing structure immediately after lbs_free_adapter() returns.
Both timer callbacks (lbs_cmd_timeout_handler and lbs_tx_lockup_handler)
access priv->driver_lock, priv->cur_cmd, priv->dev, and other fields,
which would all be use-after-free violations.
Use timer_delete_sync() instead to ensure any running timer callback
has completed before returning.
This bug was introduced in commit 8f641d93c38a ("libertas: detect TX
lockups and reset hardware") where del_timer() was used instead of
del_timer_sync() in the cleanup path. The command_timer has had the
same issue since the driver was first written. |
