In the Linux kernel, the following vulnerability has been resolved:
ata: libata-transport: fix double ata_host_put() in ata_tport_add()
In the error path in ata_tport_add(), when calling put_device(),
ata_tport_release() is called, it will put the refcount of 'ap->host'.
And then ata_host_put() is called again, the refcount is decreased
to 0, ata_host_release() is called, all ports are freed and set to
null.
When unbinding the device after failure, ata_host_stop() is called
to release the resources, it leads a null-ptr-deref(), because all
the ports all freed and null.
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
CPU: 7 PID: 18671 Comm: modprobe Kdump: loaded Tainted: G E 6.1.0-rc3+ #8
pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : ata_host_stop+0x3c/0x84 [libata]
lr : release_nodes+0x64/0xd0
Call trace:
ata_host_stop+0x3c/0x84 [libata]
release_nodes+0x64/0xd0
devres_release_all+0xbc/0x1b0
device_unbind_cleanup+0x20/0x70
really_probe+0x158/0x320
__driver_probe_device+0x84/0x120
driver_probe_device+0x44/0x120
__driver_attach+0xb4/0x220
bus_for_each_dev+0x78/0xdc
driver_attach+0x2c/0x40
bus_add_driver+0x184/0x240
driver_register+0x80/0x13c
__pci_register_driver+0x4c/0x60
ahci_pci_driver_init+0x30/0x1000 [ahci]
Fix this by removing redundant ata_host_put() in the error path.
In the Linux kernel, the following vulnerability has been resolved:
hugetlbfs: don't delete error page from pagecache
This change is very similar to the change that was made for shmem [1], and
it solves the same problem but for HugeTLBFS instead.
Currently, when poison is found in a HugeTLB page, the page is removed
from the page cache. That means that attempting to map or read that
hugepage in the future will result in a new hugepage being allocated
instead of notifying the user that the page was poisoned. As [1] states,
this is effectively memory corruption.
The fix is to leave the page in the page cache. If the user attempts to
use a poisoned HugeTLB page with a syscall, the syscall will fail with
EIO, the same error code that shmem uses. For attempts to map the page,
the thread will get a BUS_MCEERR_AR SIGBUS.
[1]: commit a76054266661 ("mm: shmem: don't truncate page if memory failure happens")
In the Linux kernel, the following vulnerability has been resolved:
drm/scheduler: fix fence ref counting
We leaked dependency fences when processes were beeing killed.
Additional to that grab a reference to the last scheduled fence.
In the Linux kernel, the following vulnerability has been resolved:
drm/drv: Fix potential memory leak in drm_dev_init()
drm_dev_init() will add drm_dev_init_release() as a callback. When
drmm_add_action() failed, the release function won't be added. As the
result, the ref cnt added by device_get() in drm_dev_init() won't be put
by drm_dev_init_release(), which leads to the memleak. Use
drmm_add_action_or_reset() instead of drmm_add_action() to prevent
memleak.
unreferenced object 0xffff88810bc0c800 (size 2048):
comm "modprobe", pid 8322, jiffies 4305809845 (age 15.292s)
hex dump (first 32 bytes):
e8 cc c0 0b 81 88 ff ff ff ff ff ff 00 00 00 00 ................
20 24 3c 0c 81 88 ff ff 18 c8 c0 0b 81 88 ff ff $<.............
backtrace:
[<000000007251f72d>] __kmalloc+0x4b/0x1c0
[<0000000045f21f26>] platform_device_alloc+0x2d/0xe0
[<000000004452a479>] platform_device_register_full+0x24/0x1c0
[<0000000089f4ea61>] 0xffffffffa0736051
[<00000000235b2441>] do_one_initcall+0x7a/0x380
[<0000000001a4a177>] do_init_module+0x5c/0x230
[<000000002bf8a8e2>] load_module+0x227d/0x2420
[<00000000637d6d0a>] __do_sys_finit_module+0xd5/0x140
[<00000000c99fc324>] do_syscall_64+0x3f/0x90
[<000000004d85aa77>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
In the Linux kernel, the following vulnerability has been resolved:
btrfs: zoned: initialize device's zone info for seeding
When performing seeding on a zoned filesystem it is necessary to
initialize each zoned device's btrfs_zoned_device_info structure,
otherwise mounting the filesystem will cause a NULL pointer dereference.
This was uncovered by fstests' testcase btrfs/163.
In the Linux kernel, the following vulnerability has been resolved:
pinctrl: devicetree: fix null pointer dereferencing in pinctrl_dt_to_map
Here is the BUG report by KASAN about null pointer dereference:
BUG: KASAN: null-ptr-deref in strcmp+0x2e/0x50
Read of size 1 at addr 0000000000000000 by task python3/2640
Call Trace:
strcmp
__of_find_property
of_find_property
pinctrl_dt_to_map
kasprintf() would return NULL pointer when kmalloc() fail to allocate.
So directly return ENOMEM, if kasprintf() return NULL pointer.
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix use-after-free bug of ns_writer on remount
If a nilfs2 filesystem is downgraded to read-only due to metadata
corruption on disk and is remounted read/write, or if emergency read-only
remount is performed, detaching a log writer and synchronizing the
filesystem can be done at the same time.
In these cases, use-after-free of the log writer (hereinafter
nilfs->ns_writer) can happen as shown in the scenario below:
Task1 Task2
-------------------------------- ------------------------------
nilfs_construct_segment
nilfs_segctor_sync
init_wait
init_waitqueue_entry
add_wait_queue
schedule
nilfs_remount (R/W remount case)
nilfs_attach_log_writer
nilfs_detach_log_writer
nilfs_segctor_destroy
kfree
finish_wait
_raw_spin_lock_irqsave
__raw_spin_lock_irqsave
do_raw_spin_lock
debug_spin_lock_before <-- use-after-free
While Task1 is sleeping, nilfs->ns_writer is freed by Task2. After Task1
waked up, Task1 accesses nilfs->ns_writer which is already freed. This
scenario diagram is based on the Shigeru Yoshida's post [1].
This patch fixes the issue by not detaching nilfs->ns_writer on remount so
that this UAF race doesn't happen. Along with this change, this patch
also inserts a few necessary read-only checks with superblock instance
where only the ns_writer pointer was used to check if the filesystem is
read-only.
In the Linux kernel, the following vulnerability has been resolved:
ALSA: hda: fix potential memleak in 'add_widget_node'
As 'kobject_add' may allocated memory for 'kobject->name' when return error.
And in this function, if call 'kobject_add' failed didn't free kobject.
So call 'kobject_put' to recycling resources.
In the Linux kernel, the following vulnerability has been resolved:
mISDN: fix possible memory leak in mISDN_dsp_element_register()
Afer commit 1fa5ae857bb1 ("driver core: get rid of struct device's
bus_id string array"), the name of device is allocated dynamically,
use put_device() to give up the reference, so that the name can be
freed in kobject_cleanup() when the refcount is 0.
The 'entry' is going to be freed in mISDN_dsp_dev_release(), so the
kfree() is removed. list_del() is called in mISDN_dsp_dev_release(),
so it need be initialized.
In the Linux kernel, the following vulnerability has been resolved:
cifs: Fix connections leak when tlink setup failed
If the tlink setup failed, lost to put the connections, then
the module refcnt leak since the cifsd kthread not exit.
Also leak the fscache info, and for next mount with fsc, it will
print the follow errors:
CIFS: Cache volume key already in use (cifs,127.0.0.1:445,TEST)
Let's check the result of tlink setup, and do some cleanup.