In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Prevent division by zero
The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Prevent division by zero
The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
drm/amd/pm: Prevent division by zero
The user can set any speed value.
If speed is greater than UINT_MAX/8, division by zero is possible.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
In the Linux kernel, the following vulnerability has been resolved:
net: tls: explicitly disallow disconnect
syzbot discovered that it can disconnect a TLS socket and then
run into all sort of unexpected corner cases. I have a vague
recollection of Eric pointing this out to us a long time ago.
Supporting disconnect is really hard, for one thing if offload
is enabled we'd need to wait for all packets to be _acked_.
Disconnect is not commonly used, disallow it.
The immediate problem syzbot run into is the warning in the strp,
but that's just the easiest bug to trigger:
WARNING: CPU: 0 PID: 5834 at net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486
RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486
Call Trace:
<TASK>
tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363
tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043
inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678
sock_recvmsg_nosec net/socket.c:1023 [inline]
sock_recvmsg+0x109/0x280 net/socket.c:1045
__sys_recvfrom+0x202/0x380 net/socket.c:2237
In the Linux kernel, the following vulnerability has been resolved:
tipc: fix memory leak in tipc_link_xmit
In case the backlog transmit queue for system-importance messages is overloaded,
tipc_link_xmit() returns -ENOBUFS but the skb list is not purged. This leads to
memory leak and failure when a skb is allocated.
This commit fixes this issue by purging the skb list before tipc_link_xmit()
returns.
In the Linux kernel, the following vulnerability has been resolved:
ata: pata_pxa: Fix potential NULL pointer dereference in pxa_ata_probe()
devm_ioremap() returns NULL on error. Currently, pxa_ata_probe() does
not check for this case, which can result in a NULL pointer dereference.
Add NULL check after devm_ioremap() to prevent this issue.
In the Linux kernel, the following vulnerability has been resolved:
PM: hibernate: Avoid deadlock in hibernate_compressor_param_set()
syzbot reported a deadlock in lock_system_sleep() (see below).
The write operation to "/sys/module/hibernate/parameters/compressor"
conflicts with the registration of ieee80211 device, resulting in a deadlock
when attempting to acquire system_transition_mutex under param_lock.
To avoid this deadlock, change hibernate_compressor_param_set() to use
mutex_trylock() for attempting to acquire system_transition_mutex and
return -EBUSY when it fails.
Task flags need not be saved or adjusted before calling
mutex_trylock(&system_transition_mutex) because the caller is not going
to end up waiting for this mutex and if it runs concurrently with system
suspend in progress, it will be frozen properly when it returns to user
space.
syzbot report:
syz-executor895/5833 is trying to acquire lock:
ffffffff8e0828c8 (system_transition_mutex){+.+.}-{4:4}, at: lock_system_sleep+0x87/0xa0 kernel/power/main.c:56
but task is already holding lock:
ffffffff8e07dc68 (param_lock){+.+.}-{4:4}, at: kernel_param_lock kernel/params.c:607 [inline]
ffffffff8e07dc68 (param_lock){+.+.}-{4:4}, at: param_attr_store+0xe6/0x300 kernel/params.c:586
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #3 (param_lock){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
ieee80211_rate_control_ops_get net/mac80211/rate.c:220 [inline]
rate_control_alloc net/mac80211/rate.c:266 [inline]
ieee80211_init_rate_ctrl_alg+0x18d/0x6b0 net/mac80211/rate.c:1015
ieee80211_register_hw+0x20cd/0x4060 net/mac80211/main.c:1531
mac80211_hwsim_new_radio+0x304e/0x54e0 drivers/net/wireless/virtual/mac80211_hwsim.c:5558
init_mac80211_hwsim+0x432/0x8c0 drivers/net/wireless/virtual/mac80211_hwsim.c:6910
do_one_initcall+0x128/0x700 init/main.c:1257
do_initcall_level init/main.c:1319 [inline]
do_initcalls init/main.c:1335 [inline]
do_basic_setup init/main.c:1354 [inline]
kernel_init_freeable+0x5c7/0x900 init/main.c:1568
kernel_init+0x1c/0x2b0 init/main.c:1457
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
-> #2 (rtnl_mutex){+.+.}-{4:4}:
__mutex_lock_common kernel/locking/mutex.c:585 [inline]
__mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
wg_pm_notification drivers/net/wireguard/device.c:80 [inline]
wg_pm_notification+0x49/0x180 drivers/net/wireguard/device.c:64
notifier_call_chain+0xb7/0x410 kernel/notifier.c:85
notifier_call_chain_robust kernel/notifier.c:120 [inline]
blocking_notifier_call_chain_robust kernel/notifier.c:345 [inline]
blocking_notifier_call_chain_robust+0xc9/0x170 kernel/notifier.c:333
pm_notifier_call_chain_robust+0x27/0x60 kernel/power/main.c:102
snapshot_open+0x189/0x2b0 kernel/power/user.c:77
misc_open+0x35a/0x420 drivers/char/misc.c:179
chrdev_open+0x237/0x6a0 fs/char_dev.c:414
do_dentry_open+0x735/0x1c40 fs/open.c:956
vfs_open+0x82/0x3f0 fs/open.c:1086
do_open fs/namei.c:3830 [inline]
path_openat+0x1e88/0x2d80 fs/namei.c:3989
do_filp_open+0x20c/0x470 fs/namei.c:4016
do_sys_openat2+0x17a/0x1e0 fs/open.c:1428
do_sys_open fs/open.c:1443 [inline]
__do_sys_openat fs/open.c:1459 [inline]
__se_sys_openat fs/open.c:1454 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1454
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
-> #1 ((pm_chain_head).rwsem){++++}-{4:4}:
down_read+0x9a/0x330 kernel/locking/rwsem.c:1524
blocking_notifier_call_chain_robust kerne
---truncated---
In the Linux kernel, the following vulnerability has been resolved:
perf: Fix hang while freeing sigtrap event
Perf can hang while freeing a sigtrap event if a related deferred
signal hadn't managed to be sent before the file got closed:
perf_event_overflow()
task_work_add(perf_pending_task)
fput()
task_work_add(____fput())
task_work_run()
____fput()
perf_release()
perf_event_release_kernel()
_free_event()
perf_pending_task_sync()
task_work_cancel() -> FAILED
rcuwait_wait_event()
Once task_work_run() is running, the list of pending callbacks is
removed from the task_struct and from this point on task_work_cancel()
can't remove any pending and not yet started work items, hence the
task_work_cancel() failure and the hang on rcuwait_wait_event().
Task work could be changed to remove one work at a time, so a work
running on the current task can always cancel a pending one, however
the wait / wake design is still subject to inverted dependencies when
remote targets are involved, as pictured by Oleg:
T1 T2
fd = perf_event_open(pid => T2->pid); fd = perf_event_open(pid => T1->pid);
close(fd) close(fd)
<IRQ> <IRQ>
perf_event_overflow() perf_event_overflow()
task_work_add(perf_pending_task) task_work_add(perf_pending_task)
</IRQ> </IRQ>
fput() fput()
task_work_add(____fput()) task_work_add(____fput())
task_work_run() task_work_run()
____fput() ____fput()
perf_release() perf_release()
perf_event_release_kernel() perf_event_release_kernel()
_free_event() _free_event()
perf_pending_task_sync() perf_pending_task_sync()
rcuwait_wait_event() rcuwait_wait_event()
Therefore the only option left is to acquire the event reference count
upon queueing the perf task work and release it from the task work, just
like it was done before 3a5465418f5f ("perf: Fix event leak upon exec and file release")
but without the leaks it fixed.
Some adjustments are necessary to make it work:
* A child event might dereference its parent upon freeing. Care must be
taken to release the parent last.
* Some places assuming the event doesn't have any reference held and
therefore can be freed right away must instead put the reference and
let the reference counting to its job.
In the Linux kernel, the following vulnerability has been resolved:
iommu/mediatek: Fix NULL pointer deference in mtk_iommu_device_group
Currently, mtk_iommu calls during probe iommu_device_register before
the hw_list from driver data is initialized. Since iommu probing issue
fix, it leads to NULL pointer dereference in mtk_iommu_device_group when
hw_list is accessed with list_first_entry (not null safe).
So, change the call order to ensure iommu_device_register is called
after the driver data are initialized.
In the Linux kernel, the following vulnerability has been resolved:
net: ppp: Add bound checking for skb data on ppp_sync_txmung
Ensure we have enough data in linear buffer from skb before accessing
initial bytes. This prevents potential out-of-bounds accesses
when processing short packets.
When ppp_sync_txmung receives an incoming package with an empty
payload:
(remote) gef⤠p *(struct pppoe_hdr *) (skb->head + skb->network_header)
$18 = {
type = 0x1,
ver = 0x1,
code = 0x0,
sid = 0x2,
length = 0x0,
tag = 0xffff8880371cdb96
}
from the skb struct (trimmed)
tail = 0x16,
end = 0x140,
head = 0xffff88803346f400 "4",
data = 0xffff88803346f416 ":\377",
truesize = 0x380,
len = 0x0,
data_len = 0x0,
mac_len = 0xe,
hdr_len = 0x0,
it is not safe to access data[2].
[pabeni@redhat.com: fixed subj typo]