In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix underflow in second superblock position calculations
Macro NILFS_SB2_OFFSET_BYTES, which computes the position of the second
superblock, underflows when the argument device size is less than 4096
bytes. Therefore, when using this macro, it is necessary to check in
advance that the device size is not less than a lower limit, or at least
that underflow does not occur.
The current nilfs2 implementation lacks this check, causing out-of-bound
block access when mounting devices smaller than 4096 bytes:
I/O error, dev loop0, sector 36028797018963960 op 0x0:(READ) flags 0x0
phys_seg 1 prio class 2
NILFS (loop0): unable to read secondary superblock (blocksize = 1024)
In addition, when trying to resize the filesystem to a size below 4096
bytes, this underflow occurs in nilfs_resize_fs(), passing a huge number
of segments to nilfs_sufile_resize(), corrupting parameters such as the
number of segments in superblocks. This causes excessive loop iterations
in nilfs_sufile_resize() during a subsequent resize ioctl, causing
semaphore ns_segctor_sem to block for a long time and hang the writer
thread:
INFO: task segctord:5067 blocked for more than 143 seconds.
Not tainted 6.2.0-rc8-syzkaller-00015-gf6feea56f66d #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:segctord state:D stack:23456 pid:5067 ppid:2
flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5293 [inline]
__schedule+0x1409/0x43f0 kernel/sched/core.c:6606
schedule+0xc3/0x190 kernel/sched/core.c:6682
rwsem_down_write_slowpath+0xfcf/0x14a0 kernel/locking/rwsem.c:1190
nilfs_transaction_lock+0x25c/0x4f0 fs/nilfs2/segment.c:357
nilfs_segctor_thread_construct fs/nilfs2/segment.c:2486 [inline]
nilfs_segctor_thread+0x52f/0x1140 fs/nilfs2/segment.c:2570
kthread+0x270/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
...
Call Trace:
<TASK>
folio_mark_accessed+0x51c/0xf00 mm/swap.c:515
__nilfs_get_page_block fs/nilfs2/page.c:42 [inline]
nilfs_grab_buffer+0x3d3/0x540 fs/nilfs2/page.c:61
nilfs_mdt_submit_block+0xd7/0x8f0 fs/nilfs2/mdt.c:121
nilfs_mdt_read_block+0xeb/0x430 fs/nilfs2/mdt.c:176
nilfs_mdt_get_block+0x12d/0xbb0 fs/nilfs2/mdt.c:251
nilfs_sufile_get_segment_usage_block fs/nilfs2/sufile.c:92 [inline]
nilfs_sufile_truncate_range fs/nilfs2/sufile.c:679 [inline]
nilfs_sufile_resize+0x7a3/0x12b0 fs/nilfs2/sufile.c:777
nilfs_resize_fs+0x20c/0xed0 fs/nilfs2/super.c:422
nilfs_ioctl_resize fs/nilfs2/ioctl.c:1033 [inline]
nilfs_ioctl+0x137c/0x2440 fs/nilfs2/ioctl.c:1301
...
This fixes these issues by inserting appropriate minimum device size
checks or anti-underflow checks, depending on where the macro is used.
In the Linux kernel, the following vulnerability has been resolved:
phy: mdio: fix memory leak
Syzbot reported memory leak in MDIO bus interface, the problem was in
wrong state logic.
MDIOBUS_ALLOCATED indicates 2 states:
1. Bus is only allocated
2. Bus allocated and __mdiobus_register() fails, but
device_register() was called
In case of device_register() has been called we should call put_device()
to correctly free the memory allocated for this device, but mdiobus_free()
calls just kfree(dev) in case of MDIOBUS_ALLOCATED state
To avoid this behaviour we need to set bus->state to MDIOBUS_UNREGISTERED
_before_ calling device_register(), because put_device() should be
called even in case of device_register() failure.
In the Linux kernel, the following vulnerability has been resolved:
HID: usbhid: free raw_report buffers in usbhid_stop
Free the unsent raw_report buffers when the device is removed.
Fixes a memory leak reported by syzbot at:
https://syzkaller.appspot.com/bug?id=7b4fa7cb1a7c2d3342a2a8a6c53371c8c418ab47
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Handle SRCU initialization failure during page track init
Check the return of init_srcu_struct(), which can fail due to OOM, when
initializing the page track mechanism. Lack of checking leads to a NULL
pointer deref found by a modified syzkaller.
[Move the call towards the beginning of kvm_arch_init_vm. - Paolo]
In the Linux kernel, the following vulnerability has been resolved:
usb: dwc2: check return value after calling platform_get_resource()
It will cause null-ptr-deref if platform_get_resource() returns NULL,
we need check the return value.
In the Linux kernel, the following vulnerability has been resolved:
HID: betop: fix slab-out-of-bounds Write in betop_probe
Syzbot reported slab-out-of-bounds Write bug in hid-betopff driver.
The problem is the driver assumes the device must have an input report but
some malicious devices violate this assumption.
So this patch checks hid_device's input is non empty before it's been used.
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (w83792d) Fix NULL pointer dereference by removing unnecessary structure field
If driver read val value sufficient for
(val & 0x08) && (!(val & 0x80)) && ((val & 0x7) == ((val >> 4) & 0x7))
from device then Null pointer dereference occurs.
(It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers)
Also lm75[] does not serve a purpose anymore after switching to
devm_i2c_new_dummy_device() in w83791d_detect_subclients().
The patch fixes possible NULL pointer dereference by removing lm75[].
Found by Linux Driver Verification project (linuxtesting.org).
[groeck: Dropped unnecessary continuation lines, fixed multipline alignment]
In the Linux kernel, the following vulnerability has been resolved:
hwmon: (w83791d) Fix NULL pointer dereference by removing unnecessary structure field
If driver read val value sufficient for
(val & 0x08) && (!(val & 0x80)) && ((val & 0x7) == ((val >> 4) & 0x7))
from device then Null pointer dereference occurs.
(It is possible if tmp = 0b0xyz1xyz, where same literals mean same numbers)
Also lm75[] does not serve a purpose anymore after switching to
devm_i2c_new_dummy_device() in w83791d_detect_subclients().
The patch fixes possible NULL pointer dereference by removing lm75[].
Found by Linux Driver Verification project (linuxtesting.org).
[groeck: Dropped unnecessary continuation lines, fixed multi-line alignment]
In the Linux kernel, the following vulnerability has been resolved:
RDMA/cma: Ensure rdma_addr_cancel() happens before issuing more requests
The FSM can run in a circle allowing rdma_resolve_ip() to be called twice
on the same id_priv. While this cannot happen without going through the
work, it violates the invariant that the same address resolution
background request cannot be active twice.
CPU 1 CPU 2
rdma_resolve_addr():
RDMA_CM_IDLE -> RDMA_CM_ADDR_QUERY
rdma_resolve_ip(addr_handler) #1
process_one_req(): for #1
addr_handler():
RDMA_CM_ADDR_QUERY -> RDMA_CM_ADDR_BOUND
mutex_unlock(&id_priv->handler_mutex);
[.. handler still running ..]
rdma_resolve_addr():
RDMA_CM_ADDR_BOUND -> RDMA_CM_ADDR_QUERY
rdma_resolve_ip(addr_handler)
!! two requests are now on the req_list
rdma_destroy_id():
destroy_id_handler_unlock():
_destroy_id():
cma_cancel_operation():
rdma_addr_cancel()
// process_one_req() self removes it
spin_lock_bh(&lock);
cancel_delayed_work(&req->work);
if (!list_empty(&req->list)) == true
! rdma_addr_cancel() returns after process_on_req #1 is done
kfree(id_priv)
process_one_req(): for #2
addr_handler():
mutex_lock(&id_priv->handler_mutex);
!! Use after free on id_priv
rdma_addr_cancel() expects there to be one req on the list and only
cancels the first one. The self-removal behavior of the work only happens
after the handler has returned. This yields a situations where the
req_list can have two reqs for the same "handle" but rdma_addr_cancel()
only cancels the first one.
The second req remains active beyond rdma_destroy_id() and will
use-after-free id_priv once it inevitably triggers.
Fix this by remembering if the id_priv has called rdma_resolve_ip() and
always cancel before calling it again. This ensures the req_list never
gets more than one item in it and doesn't cost anything in the normal flow
that never uses this strange error path.