In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: gadget: check that event count does not exceed event buffer length
The event count is read from register DWC3_GEVNTCOUNT.
There is a check for the count being zero, but not for exceeding the
event buffer length.
Check that event count does not exceed event buffer length,
avoiding an out-of-bounds access when memcpy'ing the event.
Crash log:
Unable to handle kernel paging request at virtual address ffffffc0129be000
pc : __memcpy+0x114/0x180
lr : dwc3_check_event_buf+0xec/0x348
x3 : 0000000000000030 x2 : 000000000000dfc4
x1 : ffffffc0129be000 x0 : ffffff87aad60080
Call trace:
__memcpy+0x114/0x180
dwc3_interrupt+0x24/0x34
In the Linux kernel, the following vulnerability has been resolved:
spi: spi-imx: Add check for spi_imx_setupxfer()
Add check for the return value of spi_imx_setupxfer().
spi_imx->rx and spi_imx->tx function pointer can be NULL when
spi_imx_setupxfer() return error, and make NULL pointer dereference.
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
Call trace:
0x0
spi_imx_pio_transfer+0x50/0xd8
spi_imx_transfer_one+0x18c/0x858
spi_transfer_one_message+0x43c/0x790
__spi_pump_transfer_message+0x238/0x5d4
__spi_sync+0x2b0/0x454
spi_write_then_read+0x11c/0x200
In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix WARNING "do not call blocking ops when !TASK_RUNNING"
wait_event_timeout() will set the state of the current
task to TASK_UNINTERRUPTIBLE, before doing the condition check. This
means that ksmbd_durable_scavenger_alive() will try to acquire the mutex
while already in a sleeping state. The scheduler warns us by giving
the following warning:
do not call blocking ops when !TASK_RUNNING; state=2 set at
[<0000000061515a6f>] prepare_to_wait_event+0x9f/0x6c0
WARNING: CPU: 2 PID: 4147 at kernel/sched/core.c:10099 __might_sleep+0x12f/0x160
mutex lock is not needed in ksmbd_durable_scavenger_alive().
In the Linux kernel, the following vulnerability has been resolved:
udmabuf: fix a buf size overflow issue during udmabuf creation
by casting size_limit_mb to u64 when calculate pglimit.
In the Linux kernel, the following vulnerability has been resolved:
sound/virtio: Fix cancel_sync warnings on uninitialized work_structs
Betty reported hitting the following warning:
[ 8.709131][ T221] WARNING: CPU: 2 PID: 221 at kernel/workqueue.c:4182
...
[ 8.713282][ T221] Call trace:
[ 8.713365][ T221] __flush_work+0x8d0/0x914
[ 8.713468][ T221] __cancel_work_sync+0xac/0xfc
[ 8.713570][ T221] cancel_work_sync+0x24/0x34
[ 8.713667][ T221] virtsnd_remove+0xa8/0xf8 [virtio_snd ab15f34d0dd772f6d11327e08a81d46dc9c36276]
[ 8.713868][ T221] virtsnd_probe+0x48c/0x664 [virtio_snd ab15f34d0dd772f6d11327e08a81d46dc9c36276]
[ 8.714035][ T221] virtio_dev_probe+0x28c/0x390
[ 8.714139][ T221] really_probe+0x1bc/0x4c8
...
It seems we're hitting the error path in virtsnd_probe(), which
triggers a virtsnd_remove() which iterates over the substreams
calling cancel_work_sync() on the elapsed_period work_struct.
Looking at the code, from earlier in:
virtsnd_probe()->virtsnd_build_devs()->virtsnd_pcm_parse_cfg()
We set snd->nsubstreams, allocate the snd->substreams, and if
we then hit an error on the info allocation or something in
virtsnd_ctl_query_info() fails, we will exit without having
initialized the elapsed_period work_struct.
When that error path unwinds we then call virtsnd_remove()
which as long as the substreams array is allocated, will iterate
through calling cancel_work_sync() on the uninitialized work
struct hitting this warning.
Takashi Iwai suggested this fix, which initializes the substreams
structure right after allocation, so that if we hit the error
paths we avoid trying to cleanup uninitialized data.
Note: I have not yet managed to reproduce the issue myself, so
this patch has had limited testing.
Feedback or thoughts would be appreciated!
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix kmemleak warning for percpu hashmap
Vlad Poenaru reported the following kmemleak issue:
unreferenced object 0x606fd7c44ac8 (size 32):
backtrace (crc 0):
pcpu_alloc_noprof+0x730/0xeb0
bpf_map_alloc_percpu+0x69/0xc0
prealloc_init+0x9d/0x1b0
htab_map_alloc+0x363/0x510
map_create+0x215/0x3a0
__sys_bpf+0x16b/0x3e0
__x64_sys_bpf+0x18/0x20
do_syscall_64+0x7b/0x150
entry_SYSCALL_64_after_hwframe+0x4b/0x53
Further investigation shows the reason is due to not 8-byte aligned
store of percpu pointer in htab_elem_set_ptr():
*(void __percpu **)(l->key + key_size) = pptr;
Note that the whole htab_elem alignment is 8 (for x86_64). If the key_size
is 4, that means pptr is stored in a location which is 4 byte aligned but
not 8 byte aligned. In mm/kmemleak.c, scan_block() scans the memory based
on 8 byte stride, so it won't detect above pptr, hence reporting the memory
leak.
In htab_map_alloc(), we already have
htab->elem_size = sizeof(struct htab_elem) +
round_up(htab->map.key_size, 8);
if (percpu)
htab->elem_size += sizeof(void *);
else
htab->elem_size += round_up(htab->map.value_size, 8);
So storing pptr with 8-byte alignment won't cause any problem and can fix
kmemleak too.
The issue can be reproduced with bpf selftest as well:
1. Enable CONFIG_DEBUG_KMEMLEAK config
2. Add a getchar() before skel destroy in test_hash_map() in prog_tests/for_each.c.
The purpose is to keep map available so kmemleak can be detected.
3. run './test_progs -t for_each/hash_map &' and a kmemleak should be reported.
In the Linux kernel, the following vulnerability has been resolved:
driver core: fix potential NULL pointer dereference in dev_uevent()
If userspace reads "uevent" device attribute at the same time as another
threads unbinds the device from its driver, change to dev->driver from a
valid pointer to NULL may result in crash. Fix this by using READ_ONCE()
when fetching the pointer, and take bus' drivers klist lock to make sure
driver instance will not disappear while we access it.
Use WRITE_ONCE() when setting the driver pointer to ensure there is no
tearing.
In the Linux kernel, the following vulnerability has been resolved:
scsi: target: Fix WRITE_SAME No Data Buffer crash
In newer version of the SBC specs, we have a NDOB bit that indicates there
is no data buffer that gets written out. If this bit is set using commands
like "sg_write_same --ndob" we will crash in target_core_iblock/file's
execute_write_same handlers when we go to access the se_cmd->t_data_sg
because its NULL.
This patch adds a check for the NDOB bit in the common WRITE SAME code
because we don't support it. And, it adds a check for zero SG elements in
each handler in case the initiator tries to send a normal WRITE SAME with
no data buffer.
In the Linux kernel, the following vulnerability has been resolved:
net: caif: Fix use-after-free in cfusbl_device_notify()
syzbot reported use-after-free in cfusbl_device_notify() [1]. This
causes a stack trace like below:
BUG: KASAN: use-after-free in cfusbl_device_notify+0x7c9/0x870 net/caif/caif_usb.c:138
Read of size 8 at addr ffff88807ac4e6f0 by task kworker/u4:6/1214
CPU: 0 PID: 1214 Comm: kworker/u4:6 Not tainted 5.19.0-rc3-syzkaller-00146-g92f20ff72066 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0xeb/0x467 mm/kasan/report.c:313
print_report mm/kasan/report.c:429 [inline]
kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
cfusbl_device_notify+0x7c9/0x870 net/caif/caif_usb.c:138
notifier_call_chain+0xb5/0x200 kernel/notifier.c:87
call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1945
call_netdevice_notifiers_extack net/core/dev.c:1983 [inline]
call_netdevice_notifiers net/core/dev.c:1997 [inline]
netdev_wait_allrefs_any net/core/dev.c:10227 [inline]
netdev_run_todo+0xbc0/0x10f0 net/core/dev.c:10341
default_device_exit_batch+0x44e/0x590 net/core/dev.c:11334
ops_exit_list+0x125/0x170 net/core/net_namespace.c:167
cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:594
process_one_work+0x996/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e9/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:302
</TASK>
When unregistering a net device, unregister_netdevice_many_notify()
sets the device's reg_state to NETREG_UNREGISTERING, calls notifiers
with NETDEV_UNREGISTER, and adds the device to the todo list.
Later on, devices in the todo list are processed by netdev_run_todo().
netdev_run_todo() waits devices' reference count become 1 while
rebdoadcasting NETDEV_UNREGISTER notification.
When cfusbl_device_notify() is called with NETDEV_UNREGISTER multiple
times, the parent device might be freed. This could cause UAF.
Processing NETDEV_UNREGISTER multiple times also causes inbalance of
reference count for the module.
This patch fixes the issue by accepting only first NETDEV_UNREGISTER
notification.
In the Linux kernel, the following vulnerability has been resolved:
scsi: core: Remove the /proc/scsi/${proc_name} directory earlier
Remove the /proc/scsi/${proc_name} directory earlier to fix a race
condition between unloading and reloading kernel modules. This fixes a bug
introduced in 2009 by commit 77c019768f06 ("[SCSI] fix /proc memory leak in
the SCSI core").
Fix the following kernel warning:
proc_dir_entry 'scsi/scsi_debug' already registered
WARNING: CPU: 19 PID: 27986 at fs/proc/generic.c:376 proc_register+0x27d/0x2e0
Call Trace:
proc_mkdir+0xb5/0xe0
scsi_proc_hostdir_add+0xb5/0x170
scsi_host_alloc+0x683/0x6c0
sdebug_driver_probe+0x6b/0x2d0 [scsi_debug]
really_probe+0x159/0x540
__driver_probe_device+0xdc/0x230
driver_probe_device+0x4f/0x120
__device_attach_driver+0xef/0x180
bus_for_each_drv+0xe5/0x130
__device_attach+0x127/0x290
device_initial_probe+0x17/0x20
bus_probe_device+0x110/0x130
device_add+0x673/0xc80
device_register+0x1e/0x30
sdebug_add_host_helper+0x1a7/0x3b0 [scsi_debug]
scsi_debug_init+0x64f/0x1000 [scsi_debug]
do_one_initcall+0xd7/0x470
do_init_module+0xe7/0x330
load_module+0x122a/0x12c0
__do_sys_finit_module+0x124/0x1a0
__x64_sys_finit_module+0x46/0x50
do_syscall_64+0x38/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0