In the Linux kernel, the following vulnerability has been resolved:
selinux: Add boundary check in put_entry()
Just like next_entry(), boundary check is necessary to prevent memory
out-of-bound access.
In the Linux kernel, the following vulnerability has been resolved:
PM: hibernate: defer device probing when resuming from hibernation
syzbot is reporting hung task at misc_open() [1], for there is a race
window of AB-BA deadlock which involves probe_count variable. Currently
wait_for_device_probe() from snapshot_open() from misc_open() can sleep
forever with misc_mtx held if probe_count cannot become 0.
When a device is probed by hub_event() work function, probe_count is
incremented before the probe function starts, and probe_count is
decremented after the probe function completed.
There are three cases that can prevent probe_count from dropping to 0.
(a) A device being probed stopped responding (i.e. broken/malicious
hardware).
(b) A process emulating a USB device using /dev/raw-gadget interface
stopped responding for some reason.
(c) New device probe requests keeps coming in before existing device
probe requests complete.
The phenomenon syzbot is reporting is (b). A process which is holding
system_transition_mutex and misc_mtx is waiting for probe_count to become
0 inside wait_for_device_probe(), but the probe function which is called
from hub_event() work function is waiting for the processes which are
blocked at mutex_lock(&misc_mtx) to respond via /dev/raw-gadget interface.
This patch mitigates (b) by deferring wait_for_device_probe() from
snapshot_open() to snapshot_write() and snapshot_ioctl(). Please note that
the possibility of (b) remains as long as any thread which is emulating a
USB device via /dev/raw-gadget interface can be blocked by uninterruptible
blocking operations (e.g. mutex_lock()).
Please also note that (a) and (c) are not addressed. Regarding (c), we
should change the code to wait for only one device which contains the
image for resuming from hibernation. I don't know how to address (a), for
use of timeout for wait_for_device_probe() might result in loss of user
data in the image. Maybe we should require the userland to wait for the
image device before opening /dev/snapshot interface.
In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: fix potential buffer overflow in ni_set_mc_special_registers()
The last case label can write two buffers 'mc_reg_address[j]' and
'mc_data[j]' with 'j' offset equal to SMC_NISLANDS_MC_REGISTER_ARRAY_SIZE
since there are no checks for this value in both case labels after the
last 'j++'.
Instead of changing '>' to '>=' there, add the bounds check at the start
of the second 'case' (the first one already has it).
Also, remove redundant last checks for 'j' index bigger than array size.
The expression is always false. Moreover, before or after the patch
'table->last' can be equal to SMC_NISLANDS_MC_REGISTER_ARRAY_SIZE and it
seems it can be a valid value.
Detected using the static analysis tool - Svace.
In the Linux kernel, the following vulnerability has been resolved:
ath9k: fix use-after-free in ath9k_hif_usb_rx_cb
Syzbot reported use-after-free Read in ath9k_hif_usb_rx_cb() [0]. The
problem was in incorrect htc_handle->drv_priv initialization.
Probable call trace which can trigger use-after-free:
ath9k_htc_probe_device()
/* htc_handle->drv_priv = priv; */
ath9k_htc_wait_for_target() <--- Failed
ieee80211_free_hw() <--- priv pointer is freed
<IRQ>
...
ath9k_hif_usb_rx_cb()
ath9k_hif_usb_rx_stream()
RX_STAT_INC() <--- htc_handle->drv_priv access
In order to not add fancy protection for drv_priv we can move
htc_handle->drv_priv initialization at the end of the
ath9k_htc_probe_device() and add helper macro to make
all *_STAT_* macros NULL safe, since syzbot has reported related NULL
deref in that macros [1]
In the Linux kernel, the following vulnerability has been resolved:
wifi: libertas: Fix possible refcount leak in if_usb_probe()
usb_get_dev will be called before lbs_get_firmware_async which means that
usb_put_dev need to be called when lbs_get_firmware_async fails.
In the Linux kernel, the following vulnerability has been resolved:
usb: ohci-nxp: Fix refcount leak in ohci_hcd_nxp_probe
of_parse_phandle() returns a node pointer with refcount
incremented, we should use of_node_put() on it when not need anymore.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
usb: host: Fix refcount leak in ehci_hcd_ppc_of_probe
of_find_compatible_node() returns a node pointer with refcount
incremented, we should use of_node_put() on it when done.
Add missing of_node_put() to avoid refcount leak.
In the Linux kernel, the following vulnerability has been resolved:
memstick/ms_block: Fix a memory leak
'erased_blocks_bitmap' is never freed. As it is allocated at the same time
as 'used_blocks_bitmap', it is likely that it should be freed also at the
same time.
Add the corresponding bitmap_free() in msb_data_clear().
In the Linux kernel, the following vulnerability has been resolved:
jbd2: fix assertion 'jh->b_frozen_data == NULL' failure when journal aborted
Following process will fail assertion 'jh->b_frozen_data == NULL' in
jbd2_journal_dirty_metadata():
jbd2_journal_commit_transaction
unlink(dir/a)
jh->b_transaction = trans1
jh->b_jlist = BJ_Metadata
journal->j_running_transaction = NULL
trans1->t_state = T_COMMIT
unlink(dir/b)
handle->h_trans = trans2
do_get_write_access
jh->b_modified = 0
jh->b_frozen_data = frozen_buffer
jh->b_next_transaction = trans2
jbd2_journal_dirty_metadata
is_handle_aborted
is_journal_aborted // return false
--> jbd2 abort <--
while (commit_transaction->t_buffers)
if (is_journal_aborted)
jbd2_journal_refile_buffer
__jbd2_journal_refile_buffer
WRITE_ONCE(jh->b_transaction,
jh->b_next_transaction)
WRITE_ONCE(jh->b_next_transaction, NULL)
__jbd2_journal_file_buffer(jh, BJ_Reserved)
J_ASSERT_JH(jh, jh->b_frozen_data == NULL) // assertion failure !
The reproducer (See detail in [Link]) reports:
------------[ cut here ]------------
kernel BUG at fs/jbd2/transaction.c:1629!
invalid opcode: 0000 [#1] PREEMPT SMP
CPU: 2 PID: 584 Comm: unlink Tainted: G W
5.19.0-rc6-00115-g4a57a8400075-dirty #697
RIP: 0010:jbd2_journal_dirty_metadata+0x3c5/0x470
RSP: 0018:ffffc90000be7ce0 EFLAGS: 00010202
Call Trace:
<TASK>
__ext4_handle_dirty_metadata+0xa0/0x290
ext4_handle_dirty_dirblock+0x10c/0x1d0
ext4_delete_entry+0x104/0x200
__ext4_unlink+0x22b/0x360
ext4_unlink+0x275/0x390
vfs_unlink+0x20b/0x4c0
do_unlinkat+0x42f/0x4c0
__x64_sys_unlink+0x37/0x50
do_syscall_64+0x35/0x80
After journal aborting, __jbd2_journal_refile_buffer() is executed with
holding @jh->b_state_lock, we can fix it by moving 'is_handle_aborted()'
into the area protected by @jh->b_state_lock.
In the Linux kernel, the following vulnerability has been resolved:
RDMA/srpt: Fix a use-after-free
Change the LIO port members inside struct srpt_port from regular members
into pointers. Allocate the LIO port data structures from inside
srpt_make_tport() and free these from inside srpt_make_tport(). Keep
struct srpt_device as long as either an RDMA port or a LIO target port is
associated with it. This patch decouples the lifetime of struct srpt_port
(controlled by the RDMA core) and struct srpt_port_id (controlled by LIO).
This patch fixes the following KASAN complaint:
BUG: KASAN: use-after-free in srpt_enable_tpg+0x31/0x70 [ib_srpt]
Read of size 8 at addr ffff888141cc34b8 by task check/5093
Call Trace:
<TASK>
show_stack+0x4e/0x53
dump_stack_lvl+0x51/0x66
print_address_description.constprop.0.cold+0xea/0x41e
print_report.cold+0x90/0x205
kasan_report+0xb9/0xf0
__asan_load8+0x69/0x90
srpt_enable_tpg+0x31/0x70 [ib_srpt]
target_fabric_tpg_base_enable_store+0xe2/0x140 [target_core_mod]
configfs_write_iter+0x18b/0x210
new_sync_write+0x1f2/0x2f0
vfs_write+0x3e3/0x540
ksys_write+0xbb/0x140
__x64_sys_write+0x42/0x50
do_syscall_64+0x34/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
</TASK>