| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
ceph: fix UAF in check_new_map() on session freed during unlock
check_new_map() iterates mdsc->sessions[] and for each active session
drops mdsc->mutex to perform per-session operations. The forced-close
path (rank removed from map) correctly takes a reference on s via
ceph_get_mds_session() before releasing mdsc->mutex, but three other
paths do not:
Path A (address changed): mutex_unlock → mutex_lock(&s->s_mutex)
Path B (reconnect): mutex_unlock → send_mds_reconnect(mdsc, s)
Path C (active transition): mutex_unlock → mutex_lock(&s->s_mutex)
Without the extra reference, another thread can acquire mdsc->mutex
during the unlock window, call __unregister_session() which drops the
last reference on s, and free it. The original thread then accesses
freed memory via s->s_mutex.
Fix by adding ceph_get_mds_session(s) before each mutex_unlock and
ceph_put_mds_session(s) after the corresponding mutex_lock, matching
the pattern already used in the forced-close path.
Race timeline (Path A):
Thread A (check_new_map) Thread B (another map update
holds mdsc->mutex or session teardown)
-------------------------- --------------------------
s = mdsc->sessions[i]
(refcount == 1, held only by
sessions[] array)
mutex_unlock(&mdsc->mutex)
---> acquires mdsc->mutex
__unregister_session(mdsc, s)
sessions[i] = NULL
ceph_put_mds_session(s)
refcount: 1 -> 0
kfree(s) <--- freed!
mutex_lock(&s->s_mutex)
UAF on freed s->s_mutex |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_sync: hold conn in hci_connect_big_sync() callback
There is theoretical UAF if the conn is freed while the hci_sync task is
running.
Hold refcount to avoid that. Handle NULL hcon, return 0 + do nothing to
match the previous behavior. |
| In the Linux kernel, the following vulnerability has been resolved:
i3c: mipi-i3c-hci: Fix race in i3c_hci_addr_to_dev()
i3c_hci_addr_to_dev() walks bus->devs.i3c, which is protected by
bus.lock (rwsem). However, it is invoked from the MIPI I3C HCI IRQ
handler, which cannot take bus.lock. This allows concurrent device
addition/removal in the I3C core to modify the list while it is being
traversed, potentially leading to use-after-free or crashes.
Remove the dependency on the bus device list and introduce a dedicated
lookup table. Add an ibi_devs[] array indexed by DAT entry, maintained
under hci->lock. Update the array when IBIs are enabled or disabled,
so that it always reflects the set of devices allowed to generate IBIs.
Also update when IBIs are freed, to cover the corner case when an IBI is
freed without first being disabled (e.g. oldedev in
i3c_master_add_i3c_dev_locked()).
Move i3c_hci_addr_to_dev() into core.c, reimplement it using the new
array, and add a lockdep assertion to enforce that hci->lock is held
by callers.
Demote a message in PIO and DMA IBI handling, from an error to a debug
message, because there is a race window when the condition can arise
normally. |
| In the Linux kernel, the following vulnerability has been resolved:
power: supply: max77705: Free allocated workqueue and fix removal order
Use devm interface for allocating workqueue to fix two bugs at the same
time:
1. Driver leaks the memory on remove(), because the workqueue is not
destroyed.
2. Driver allocates workqueue and then registers interrupt handlers
with devm interface. This means that probe error paths will not use a
reversed order, but first destroy the workqueue and then, via devm
release handlers, free the interrupt.
The interrupt handler schedules work on this exact workqueue, thus if
interrupt is hit in this short time window - after destroying
workqueue, but before devm() frees the interrupt - the schedulled
work will lead to use of freed memory.
Change is not equivalent in the workqueue itself: use non-legacy API
which does not set (__WQ_LEGACY | WQ_MEM_RECLAIM). The workqueue is
used to update power supply (power_supply_changed()) status, thus there
is no point to run it for memory reclaim. Note that dev_name() is not
directly used in second argument to prevent possible unlikely parsing
any "%" character in device name as format. |
| In the Linux kernel, the following vulnerability has been resolved:
pseries/papr-hvpipe: Fix race with interrupt handler
While executing ->ioctl handler or ->release handler, if an interrupt
fires on the same cpu, then we can enter into a deadlock.
This patch fixes both these handlers to take spin_lock_irq{save|restore}
versions of the lock to prevent this deadlock. |
| In the Linux kernel, the following vulnerability has been resolved:
posix-cpu-timers: Prevent UAF caused by non-leader exec() race
Wongi and Jungwoo decoded and reported a non-leader exec() related race
which can result in an UAF:
sys_timer_delete() exec()
posix_cpu_timer_del()
// Observes old leader
p = pid_task(pid, pid_type); de_thread()
switch_leader();
release_task(old_leader)
__exit_signal(old_leader)
sighand = lock(old_leader, sighand);
posix_cpu_timers*_exit();
sighand = lock_task_sighand(p) unhash_task(old_leader);
sh = lock(p, sighand) old_leader->sighand = NULL;
unlock(sighand);
(p->sighand == NULL)
unlock(sh)
return NULL;
// Returns without action
if(!sighand)
return 0;
free_posix_timer();
This is "harmless" unless the deleted timer was armed and enqueued in
p->signal because on exec() a TGID targeted timer is inherited.
As sys_timer_delete() freed the underlying posix timer object
run_posix_cpu_timers() or any timerqueue related add/delete operations on
other timers will access the freed object's timerqueue node, which results
in an UAF.
There is a similar problem vs. posix_cpu_timer_set(). For regular posix
timers it just transiently returns -ESRCH to user space, but for the use
case in do_cpu_nanosleep() it's the same UAF just that the k_itimer is
allocated on the stack.
Also posix_cpu_timer_rearm() fails to rearm the timer, which means it stops
to expire.
While debating solutions Frederic pointed out another problem:
posix_cpu_timer_del(tmr)
__exit_signal(p)
posix_cpu_timers*_exit(p);
unhash_task(p);
p->sighand = NULL;
sh = lock_task_sighand(p)
sighand = p->sighand;
if (!sighand)
return NULL;
lock(sighand);
if (!sh)
WARN_ON_ONCE(timer_queued(tmr));
On weakly ordered architectures it is not guaranteed that
posix_cpu_timer_del() will observe the stores in posix_cpu_timers*_exit()
when p->sighand is observed as NULL, which means the WARN() can be a false
positive.
Solve these issues by:
1) Changing the store in __exit_signal() to smp_store_release().
2) Adding a smp_acquire__after_ctrl_dep() into the !sighand path
of lock_task_sighand().
3) Creating a helper function for looking up the task and locking sighand
which does not return when sighand == NULL. Instead it retries the
task lookup and only if that fails it gives up.
4) Using that helper in the three affected functions.
#1/#2 ensures that the reader side which observes sighand == NULL also
observes all preceeding stores, i.e. the stores in posix_cpu_timers*_exit()
and the ones in unhash_task().
#3 ensures that the above described non-leader exec() situation is handled
gracefully. When the task lookup returns the old leader, but sighand ==
NULL then it retries. In the non-leader exec() case the subsequent task
lookup will observe the new leader due to #1/#2. In normal exit() scenarios
the subsequent lookup fails.
When the task lookup fails, the function also checks whether the timer is
still enqueued and issues a warning if that's the case. Unfortunately there
is nothing which can be done about it, but as the task is already not
longer visible the timer should not be accessed anymore. This check also
requires memory ordering, which is not provided when the first lookup
fails. To achieve that the check is preceeded by a smp_rmb() which pairs
with the smp_wmb() in write_seqlock() in __exit_signal(). That ensures that
the stores in posix_cpu_timers*_exit() are visible.
The history of the non-leader exec() issue goes back to the early days of
posix CPU timers, which stored a pointer to the group leader task in the
timer. That obviously fails when a non-leader exec() switches the leader.
commit e0a70217107e ("posix-cpu-timers: workaround to suppress the problems
with mt exec") added a temporary workaround for that in 2010 which surv
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ipv4: igmp: remove multicast group from hash table on device destruction
When a device is destroyed under RTNL, ip_mc_destroy_dev() iterates through
the multicast list and calls ip_ma_put() on each membership, scheduling
them for RCU reclamation. However, they are not unlinked from the device's
multicast hash table (mc_hash).
Since the device remains published in dev->ip_ptr until after
ip_mc_destroy_dev() completes, concurrent RCU readers traversing mc_hash
can still locate and access the multicast group after its refcount is
decremented. If the RCU callback runs and frees the group while a reader is
accessing it, a use-after-free occurs.
Fix this by unlinking the multicast group from mc_hash using
ip_mc_hash_remove() before scheduling it for reclamation.
BUG: KASAN: slab-use-after-free in ip_check_mc_rcu+0x149/0x3f0
Read of size 4 at addr ffff888009bf1408 by task mausezahn/2276
Call Trace:
<IRQ>
dump_stack_lvl+0x67/0x90
print_report+0x175/0x7c0
kasan_report+0x147/0x180
ip_check_mc_rcu+0x149/0x3f0
udp_v4_early_demux+0x36d/0x12d0
ip_rcv_finish_core+0xb8b/0x1390
ip_rcv_finish+0x54/0x120
NF_HOOK+0x213/0x2b0
__netif_receive_skb+0x126/0x340
process_backlog+0x4f2/0xf00
__napi_poll+0x92/0x2c0
net_rx_action+0x583/0xc60
handle_softirqs+0x236/0x7f0
do_softirq+0x57/0x80
</IRQ>
Allocated by task 2239:
kasan_save_track+0x3e/0x80
__kasan_kmalloc+0x72/0x90
____ip_mc_inc_group+0x31a/0xa40
__ip_mc_join_group+0x334/0x3f0
do_ip_setsockopt+0x16fa/0x2010
ip_setsockopt+0x3f/0x90
do_sock_setsockopt+0x1ad/0x300
Freed by task 0:
kasan_save_track+0x3e/0x80
kasan_save_free_info+0x40/0x50
__kasan_slab_free+0x3a/0x60
__rcu_free_sheaf_prepare+0xd4/0x220
rcu_free_sheaf+0x36/0x190
rcu_core+0x8d9/0x12f0
handle_softirqs+0x236/0x7f0 |
| 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:
xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()
Fix the race by pruning the bin while still holding xfrm_policy_lock,
before dropping it. Use __xfrm_policy_inexact_prune_bin() directly since
the lock is already held. The wrapper xfrm_policy_inexact_prune_bin()
becomes unused and is removed.
Race:
CPU0 (XFRM_MSG_DELPOLICY) CPU1 (XFRM_MSG_NEWSPDINFO)
========================== ==========================
xfrm_policy_bysel_ctx():
spin_lock_bh(xfrm_policy_lock)
bin = xfrm_policy_inexact_lookup()
__xfrm_policy_unlink(pol)
spin_unlock_bh(xfrm_policy_lock)
xfrm_policy_kill(ret)
// wide window, lock not held
xfrm_hash_rebuild():
spin_lock_bh(xfrm_policy_lock)
__xfrm_policy_inexact_flush():
kfree_rcu(bin) // bin freed
spin_unlock_bh(xfrm_policy_lock)
xfrm_policy_inexact_prune_bin(bin)
// UAF: bin is freed |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: timer: Fix UAF at snd_timer_user_params()
At releasing a timer object, e.g. when a userspace timer
(CONFIG_SND_UTIMER) gets closed and snd_timer_free() is called, it
tries to detach the timer instances and release the resources.
However, it's still possible that other in-flight tasks are holding
the timer instance where the to-be-deleted timer object is associated,
and this may lead to racy accesses.
Fortunately, most of ioctls dealing with the timer instance list
already have the protection with register_mutex, and this also avoids
such races. But, SNDRV_TIMER_IOCTL_PARAMS isn't protected, hence the
concurrent ioctl may lead to use-after-free.
This patch just adds the guard with register_mutex to protect
snd_timer_user_params() for covering the code path as a quick
workaround. It's no hot-path but rather a rarely issued ioctl, so the
performance penalty doesn't matter. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Free reuseport cBPF prog after RCU grace period.
Eulgyu Kim reported the splat below with a repro. [0]
The repro sets up a UDP reuseport group with a cBPF prog and
replaces it with a new one while another thread is sending
a UDP packet to the group.
The reuseport prog is freed by sk_reuseport_prog_free().
bpf_prog_put() is called for "e"BPF prog to destruct through
multiple stages while cBPF prog is freed immediately by
bpf_release_orig_filter() and bpf_prog_free().
If a reuseport prog is detached from the setsockopt() path
(reuseport_attach_prog() or reuseport_detach_prog()),
sk_reuseport_prog_free() is called without waiting for RCU
readers to complete, resulting in various bugs.
Let's defer freeing the reuseport cBPF prog after one RCU
grace period.
Note "e"BPF prog is safe as is unless the fast path starts
to touch fields destroyed in bpf_prog_put_deferred() and
__bpf_prog_put_noref().
[0]:
BUG: KASAN: vmalloc-out-of-bounds in reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
Read of size 4 at addr ffffc9000051e004 by task slowme/10208
CPU: 6 UID: 1000 PID: 10208 Comm: slowme Not tainted 7.0.0-geb7ac95ff75e #32 PREEMPT(full)
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
Call Trace:
<IRQ>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
reuseport_select_sock+0xedc/0x1220 net/core/sock_reuseport.c:596
udp4_lib_lookup2+0x3bc/0x950 net/ipv4/udp.c:495
__udp4_lib_lookup+0x768/0xe20 net/ipv4/udp.c:723
__udp4_lib_lookup_skb+0x297/0x390 net/ipv4/udp.c:752
__udp4_lib_rcv+0x1312/0x2620 net/ipv4/udp.c:2752
ip_protocol_deliver_rcu+0x282/0x440 net/ipv4/ip_input.c:207
ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:241
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318
__netif_receive_skb_one_core net/core/dev.c:6181 [inline]
__netif_receive_skb net/core/dev.c:6294 [inline]
process_backlog+0xaa4/0x1960 net/core/dev.c:6645
__napi_poll+0xae/0x340 net/core/dev.c:7709
napi_poll net/core/dev.c:7772 [inline]
net_rx_action+0x5d7/0xf50 net/core/dev.c:7929
handle_softirqs+0x22b/0x870 kernel/softirq.c:622
do_softirq+0x76/0xd0 kernel/softirq.c:523
</IRQ>
<TASK>
__local_bh_enable_ip+0xf8/0x130 kernel/softirq.c:450
local_bh_enable include/linux/bottom_half.h:33 [inline]
rcu_read_unlock_bh include/linux/rcupdate.h:924 [inline]
__dev_queue_xmit+0x1dd7/0x3710 net/core/dev.c:4890
neigh_output include/net/neighbour.h:556 [inline]
ip_finish_output2+0xca9/0x1070 net/ipv4/ip_output.c:237
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip_output+0x29f/0x450 net/ipv4/ip_output.c:438
ip_send_skb+0x45/0xc0 net/ipv4/ip_output.c:1508
udp_send_skb+0xb04/0x1510 net/ipv4/udp.c:1195
udp_sendmsg+0x1a71/0x2350 net/ipv4/udp.c:1485
sock_sendmsg_nosec net/socket.c:727 [inline]
__sock_sendmsg net/socket.c:742 [inline]
__sys_sendto+0x554/0x680 net/socket.c:2206
__do_sys_sendto net/socket.c:2213 [inline]
__se_sys_sendto net/socket.c:2209 [inline]
__x64_sys_sendto+0xde/0x100 net/socket.c:2209
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x160/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x415a2d
Code: b3 66 2e 0f 1f 84 00 00 00 00 00 66 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6bc31e41e8 EFLAGS: 00000212 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f6bc31e4cdc RCX: 0000000000415a2d
RDX: 0000000000000001 RSI: 00007f6bc31e421f RDI: 0000000000000003
RBP: 00007f6bc31e4240 R08: 00007f6bc31e4220 R09: 0000000000000010
R10: 0000000000000000 R11:
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: Fix potential use-after-free issue when stopping watchdog task
Watchdog task might end between send_sig() and kthread_stop() calls, what
results in the use-after-free issue. Fix this by increasing watchdog task
reference count before calling send_sig() and dropping it by switching to
kthread_stop_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: fix fanout UAF in packet_release() via NETDEV_UP race
`packet_release()` has a race window where `NETDEV_UP` can re-register a
socket into a fanout group's `arr[]` array. The re-registration is not
cleaned up by `fanout_release()`, leaving a dangling pointer in the fanout
array.
`packet_release()` does NOT zero `po->num` in its `bind_lock` section.
After releasing `bind_lock`, `po->num` is still non-zero and `po->ifindex`
still matches the bound device. A concurrent `packet_notifier(NETDEV_UP)`
that already found the socket in `sklist` can re-register the hook.
For fanout sockets, this re-registration calls `__fanout_link(sk, po)`
which adds the socket back into `f->arr[]` and increments `f->num_members`,
but does NOT increment `f->sk_ref`.
The fix sets `po->num` to zero in `packet_release` while `bind_lock` is
held to prevent NETDEV_UP from linking, preventing the race window.
This bug was found following an additional audit with Claude Code based
on CVE-2025-38617. |
| In the Linux kernel, the following vulnerability has been resolved:
PM: runtime: Fix a race condition related to device removal
The following code in pm_runtime_work() may dereference the dev->parent
pointer after the parent device has been freed:
/* Maybe the parent is now able to suspend. */
if (parent && !parent->power.ignore_children) {
spin_unlock(&dev->power.lock);
spin_lock(&parent->power.lock);
rpm_idle(parent, RPM_ASYNC);
spin_unlock(&parent->power.lock);
spin_lock(&dev->power.lock);
}
Fix this by inserting a flush_work() call in pm_runtime_remove().
Without this patch blktest block/001 triggers the following complaint
sporadically:
BUG: KASAN: slab-use-after-free in lock_acquire+0x70/0x160
Read of size 1 at addr ffff88812bef7198 by task kworker/u553:1/3081
Workqueue: pm pm_runtime_work
Call Trace:
<TASK>
dump_stack_lvl+0x61/0x80
print_address_description.constprop.0+0x8b/0x310
print_report+0xfd/0x1d7
kasan_report+0xd8/0x1d0
__kasan_check_byte+0x42/0x60
lock_acquire.part.0+0x38/0x230
lock_acquire+0x70/0x160
_raw_spin_lock+0x36/0x50
rpm_suspend+0xc6a/0xfe0
rpm_idle+0x578/0x770
pm_runtime_work+0xee/0x120
process_one_work+0xde3/0x1410
worker_thread+0x5eb/0xfe0
kthread+0x37b/0x480
ret_from_fork+0x6cb/0x920
ret_from_fork_asm+0x11/0x20
</TASK>
Allocated by task 4314:
kasan_save_stack+0x2a/0x50
kasan_save_track+0x18/0x40
kasan_save_alloc_info+0x3d/0x50
__kasan_kmalloc+0xa0/0xb0
__kmalloc_noprof+0x311/0x990
scsi_alloc_target+0x122/0xb60 [scsi_mod]
__scsi_scan_target+0x101/0x460 [scsi_mod]
scsi_scan_channel+0x179/0x1c0 [scsi_mod]
scsi_scan_host_selected+0x259/0x2d0 [scsi_mod]
store_scan+0x2d2/0x390 [scsi_mod]
dev_attr_store+0x43/0x80
sysfs_kf_write+0xde/0x140
kernfs_fop_write_iter+0x3ef/0x670
vfs_write+0x506/0x1470
ksys_write+0xfd/0x230
__x64_sys_write+0x76/0xc0
x64_sys_call+0x213/0x1810
do_syscall_64+0xee/0xfc0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Freed by task 4314:
kasan_save_stack+0x2a/0x50
kasan_save_track+0x18/0x40
kasan_save_free_info+0x3f/0x50
__kasan_slab_free+0x67/0x80
kfree+0x225/0x6c0
scsi_target_dev_release+0x3d/0x60 [scsi_mod]
device_release+0xa3/0x220
kobject_cleanup+0x105/0x3a0
kobject_put+0x72/0xd0
put_device+0x17/0x20
scsi_device_dev_release+0xacf/0x12c0 [scsi_mod]
device_release+0xa3/0x220
kobject_cleanup+0x105/0x3a0
kobject_put+0x72/0xd0
put_device+0x17/0x20
scsi_device_put+0x7f/0xc0 [scsi_mod]
sdev_store_delete+0xa5/0x120 [scsi_mod]
dev_attr_store+0x43/0x80
sysfs_kf_write+0xde/0x140
kernfs_fop_write_iter+0x3ef/0x670
vfs_write+0x506/0x1470
ksys_write+0xfd/0x230
__x64_sys_write+0x76/0xc0
x64_sys_call+0x213/0x1810 |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: rawsock: cancel tx_work before socket teardown
In rawsock_release(), cancel any pending tx_work and purge the write
queue before orphaning the socket. rawsock_tx_work runs on the system
workqueue and calls nfc_data_exchange which dereferences the NCI
device. Without synchronization, tx_work can race with socket and
device teardown when a process is killed (e.g. by SIGKILL), leading
to use-after-free or leaked references.
Set SEND_SHUTDOWN first so that if tx_work is already running it will
see the flag and skip transmitting, then use cancel_work_sync to wait
for any in-progress execution to finish, and finally purge any
remaining queued skbs. |
| In the Linux kernel, the following vulnerability has been resolved:
net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs
When shrinking the number of real tx queues,
netif_set_real_num_tx_queues() calls qdisc_reset_all_tx_gt() to flush
qdiscs for queues which will no longer be used.
qdisc_reset_all_tx_gt() currently serializes qdisc_reset() with
qdisc_lock(). However, for lockless qdiscs, the dequeue path is
serialized by qdisc_run_begin/end() using qdisc->seqlock instead, so
qdisc_reset() can run concurrently with __qdisc_run() and free skbs
while they are still being dequeued, leading to UAF.
This can easily be reproduced on e.g. virtio-net by imposing heavy
traffic while frequently changing the number of queue pairs:
iperf3 -ub0 -c $peer -t 0 &
while :; do
ethtool -L eth0 combined 1
ethtool -L eth0 combined 2
done
With KASAN enabled, this leads to reports like:
BUG: KASAN: slab-use-after-free in __qdisc_run+0x133f/0x1760
...
Call Trace:
<TASK>
...
__qdisc_run+0x133f/0x1760
__dev_queue_xmit+0x248f/0x3550
ip_finish_output2+0xa42/0x2110
ip_output+0x1a7/0x410
ip_send_skb+0x2e6/0x480
udp_send_skb+0xb0a/0x1590
udp_sendmsg+0x13c9/0x1fc0
...
</TASK>
Allocated by task 1270 on cpu 5 at 44.558414s:
...
alloc_skb_with_frags+0x84/0x7c0
sock_alloc_send_pskb+0x69a/0x830
__ip_append_data+0x1b86/0x48c0
ip_make_skb+0x1e8/0x2b0
udp_sendmsg+0x13a6/0x1fc0
...
Freed by task 1306 on cpu 3 at 44.558445s:
...
kmem_cache_free+0x117/0x5e0
pfifo_fast_reset+0x14d/0x580
qdisc_reset+0x9e/0x5f0
netif_set_real_num_tx_queues+0x303/0x840
virtnet_set_channels+0x1bf/0x260 [virtio_net]
ethnl_set_channels+0x684/0xae0
ethnl_default_set_doit+0x31a/0x890
...
Serialize qdisc_reset_all_tx_gt() against the lockless dequeue path by
taking qdisc->seqlock for TCQ_F_NOLOCK qdiscs, matching the
serialization model already used by dev_reset_queue().
Additionally clear QDISC_STATE_NON_EMPTY after reset so the qdisc state
reflects an empty queue, avoiding needless re-scheduling. |
| In the Linux kernel, the following vulnerability has been resolved:
macvlan: observe an RCU grace period in macvlan_common_newlink() error path
valis reported that a race condition still happens after my prior patch.
macvlan_common_newlink() might have made @dev visible before
detecting an error, and its caller will directly call free_netdev(dev).
We must respect an RCU period, either in macvlan or the core networking
stack.
After adding a temporary mdelay(1000) in macvlan_forward_source_one()
to open the race window, valis repro was:
ip link add p1 type veth peer p2
ip link set address 00:00:00:00:00:20 dev p1
ip link set up dev p1
ip link set up dev p2
ip link add mv0 link p2 type macvlan mode source
(ip link add invalid% link p2 type macvlan mode source macaddr add
00:00:00:00:00:20 &) ; sleep 0.5 ; ping -c1 -I p1 1.2.3.4
PING 1.2.3.4 (1.2.3.4): 56 data bytes
RTNETLINK answers: Invalid argument
BUG: KASAN: slab-use-after-free in macvlan_forward_source
(drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
Read of size 8 at addr ffff888016bb89c0 by task e/175
CPU: 1 UID: 1000 PID: 175 Comm: e Not tainted 6.19.0-rc8+ #33 NONE
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
Call Trace:
<IRQ>
dump_stack_lvl (lib/dump_stack.c:123)
print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)
? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
kasan_report (mm/kasan/report.c:597)
? macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
macvlan_forward_source (drivers/net/macvlan.c:408 drivers/net/macvlan.c:444)
? tasklet_init (kernel/softirq.c:983)
macvlan_handle_frame (drivers/net/macvlan.c:501)
Allocated by task 169:
kasan_save_stack (mm/kasan/common.c:58)
kasan_save_track (./arch/x86/include/asm/current.h:25
mm/kasan/common.c:70 mm/kasan/common.c:79)
__kasan_kmalloc (mm/kasan/common.c:419)
__kvmalloc_node_noprof (./include/linux/kasan.h:263 mm/slub.c:5657
mm/slub.c:7140)
alloc_netdev_mqs (net/core/dev.c:12012)
rtnl_create_link (net/core/rtnetlink.c:3648)
rtnl_newlink (net/core/rtnetlink.c:3830 net/core/rtnetlink.c:3957
net/core/rtnetlink.c:4072)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
netlink_rcv_skb (net/netlink/af_netlink.c:2550)
netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
netlink_sendmsg (net/netlink/af_netlink.c:1894)
__sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2206)
__x64_sys_sendto (net/socket.c:2209)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)
Freed by task 169:
kasan_save_stack (mm/kasan/common.c:58)
kasan_save_track (./arch/x86/include/asm/current.h:25
mm/kasan/common.c:70 mm/kasan/common.c:79)
kasan_save_free_info (mm/kasan/generic.c:587)
__kasan_slab_free (mm/kasan/common.c:287)
kfree (mm/slub.c:6674 mm/slub.c:6882)
rtnl_newlink (net/core/rtnetlink.c:3845 net/core/rtnetlink.c:3957
net/core/rtnetlink.c:4072)
rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
netlink_rcv_skb (net/netlink/af_netlink.c:2550)
netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
netlink_sendmsg (net/netlink/af_netlink.c:1894)
__sys_sendto (net/socket.c:727 net/socket.c:742 net/socket.c:2206)
__x64_sys_sendto (net/socket.c:2209)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131) |
| In the Linux kernel, the following vulnerability has been resolved:
quota: flush quota_release_work upon quota writeback
One of the paths quota writeback is called from is:
freeze_super()
sync_filesystem()
ext4_sync_fs()
dquot_writeback_dquots()
Since we currently don't always flush the quota_release_work queue in
this path, we can end up with the following race:
1. dquot are added to releasing_dquots list during regular operations.
2. FS Freeze starts, however, this does not flush the quota_release_work queue.
3. Freeze completes.
4. Kernel eventually tries to flush the workqueue while FS is frozen which
hits a WARN_ON since transaction gets started during frozen state:
ext4_journal_check_start+0x28/0x110 [ext4] (unreliable)
__ext4_journal_start_sb+0x64/0x1c0 [ext4]
ext4_release_dquot+0x90/0x1d0 [ext4]
quota_release_workfn+0x43c/0x4d0
Which is the following line:
WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
Which ultimately results in generic/390 failing due to dmesg
noise. This was detected on powerpc machine 15 cores.
To avoid this, make sure to flush the workqueue during
dquot_writeback_dquots() so we dont have any pending workitems after
freeze. |
| A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server. |
