In the Linux kernel, the following vulnerability has been resolved:
net: mdio: fix undefined behavior in bit shift for __mdiobus_register
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in drivers/net/phy/mdio_bus.c:586:27
left shift of 1 by 31 places cannot be represented in type 'int'
Call Trace:
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
__mdiobus_register+0x49d/0x4e0
fixed_mdio_bus_init+0xd8/0x12d
do_one_initcall+0x76/0x430
kernel_init_freeable+0x3b3/0x422
kernel_init+0x24/0x1e0
ret_from_fork+0x1f/0x30
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
ACPI: APEI: Fix integer overflow in ghes_estatus_pool_init()
Change num_ghes from int to unsigned int, preventing an overflow
and causing subsequent vmalloc() to fail.
The overflow happens in ghes_estatus_pool_init() when calculating
len during execution of the statement below as both multiplication
operands here are signed int:
len += (num_ghes * GHES_ESOURCE_PREALLOC_MAX_SIZE);
The following call trace is observed because of this bug:
[ 9.317108] swapper/0: vmalloc error: size 18446744071562596352, exceeds total pages, mode:0xcc0(GFP_KERNEL), nodemask=(null),cpuset=/,mems_allowed=0-1
[ 9.317131] Call Trace:
[ 9.317134] <TASK>
[ 9.317137] dump_stack_lvl+0x49/0x5f
[ 9.317145] dump_stack+0x10/0x12
[ 9.317146] warn_alloc.cold+0x7b/0xdf
[ 9.317150] ? __device_attach+0x16a/0x1b0
[ 9.317155] __vmalloc_node_range+0x702/0x740
[ 9.317160] ? device_add+0x17f/0x920
[ 9.317164] ? dev_set_name+0x53/0x70
[ 9.317166] ? platform_device_add+0xf9/0x240
[ 9.317168] __vmalloc_node+0x49/0x50
[ 9.317170] ? ghes_estatus_pool_init+0x43/0xa0
[ 9.317176] vmalloc+0x21/0x30
[ 9.317177] ghes_estatus_pool_init+0x43/0xa0
[ 9.317179] acpi_hest_init+0x129/0x19c
[ 9.317185] acpi_init+0x434/0x4a4
[ 9.317188] ? acpi_sleep_proc_init+0x2a/0x2a
[ 9.317190] do_one_initcall+0x48/0x200
[ 9.317195] kernel_init_freeable+0x221/0x284
[ 9.317200] ? rest_init+0xe0/0xe0
[ 9.317204] kernel_init+0x1a/0x130
[ 9.317205] ret_from_fork+0x22/0x30
[ 9.317208] </TASK>
[ rjw: Subject and changelog edits ]
In the Linux kernel, the following vulnerability has been resolved:
media: meson: vdec: fix possible refcount leak in vdec_probe()
v4l2_device_unregister need to be called to put the refcount got by
v4l2_device_register when vdec_probe fails or vdec_remove is called.
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix BUG_ON() when directory entry has invalid rec_len
The rec_len field in the directory entry has to be a multiple of 4. A
corrupted filesystem image can be used to hit a BUG() in
ext4_rec_len_to_disk(), called from make_indexed_dir().
------------[ cut here ]------------
kernel BUG at fs/ext4/ext4.h:2413!
...
RIP: 0010:make_indexed_dir+0x53f/0x5f0
...
Call Trace:
<TASK>
? add_dirent_to_buf+0x1b2/0x200
ext4_add_entry+0x36e/0x480
ext4_add_nondir+0x2b/0xc0
ext4_create+0x163/0x200
path_openat+0x635/0xe90
do_filp_open+0xb4/0x160
? __create_object.isra.0+0x1de/0x3b0
? _raw_spin_unlock+0x12/0x30
do_sys_openat2+0x91/0x150
__x64_sys_open+0x6c/0xa0
do_syscall_64+0x3c/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
The fix simply adds a call to ext4_check_dir_entry() to validate the
directory entry, returning -EFSCORRUPTED if the entry is invalid.
In the Linux kernel, the following vulnerability has been resolved:
drm/amdkfd: Fix NULL pointer dereference in svm_migrate_to_ram()
./drivers/gpu/drm/amd/amdkfd/kfd_migrate.c:985:58-62: ERROR: p is NULL but dereferenced.
In the Linux kernel, the following vulnerability has been resolved:
capabilities: fix undefined behavior in bit shift for CAP_TO_MASK
Shifting signed 32-bit value by 31 bits is undefined, so changing
significant bit to unsigned. The UBSAN warning calltrace like below:
UBSAN: shift-out-of-bounds in security/commoncap.c:1252:2
left shift of 1 by 31 places cannot be represented in type 'int'
Call Trace:
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
cap_task_prctl+0x561/0x6f0
security_task_prctl+0x5a/0xb0
__x64_sys_prctl+0x61/0x8f0
do_syscall_64+0x58/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix deadlock in nilfs_count_free_blocks()
A semaphore deadlock can occur if nilfs_get_block() detects metadata
corruption while locating data blocks and a superblock writeback occurs at
the same time:
task 1 task 2
------ ------
* A file operation *
nilfs_truncate()
nilfs_get_block()
down_read(rwsem A) <--
nilfs_bmap_lookup_contig()
... generic_shutdown_super()
nilfs_put_super()
* Prepare to write superblock *
down_write(rwsem B) <--
nilfs_cleanup_super()
* Detect b-tree corruption * nilfs_set_log_cursor()
nilfs_bmap_convert_error() nilfs_count_free_blocks()
__nilfs_error() down_read(rwsem A) <--
nilfs_set_error()
down_write(rwsem B) <--
*** DEADLOCK ***
Here, nilfs_get_block() readlocks rwsem A (= NILFS_MDT(dat_inode)->mi_sem)
and then calls nilfs_bmap_lookup_contig(), but if it fails due to metadata
corruption, __nilfs_error() is called from nilfs_bmap_convert_error()
inside the lock section.
Since __nilfs_error() calls nilfs_set_error() unless the filesystem is
read-only and nilfs_set_error() attempts to writelock rwsem B (=
nilfs->ns_sem) to write back superblock exclusively, hierarchical lock
acquisition occurs in the order rwsem A -> rwsem B.
Now, if another task starts updating the superblock, it may writelock
rwsem B during the lock sequence above, and can deadlock trying to
readlock rwsem A in nilfs_count_free_blocks().
However, there is actually no need to take rwsem A in
nilfs_count_free_blocks() because it, within the lock section, only reads
a single integer data on a shared struct with
nilfs_sufile_get_ncleansegs(). This has been the case after commit
aa474a220180 ("nilfs2: add local variable to cache the number of clean
segments"), that is, even before this bug was introduced.
So, this resolves the deadlock problem by just not taking the semaphore in
nilfs_count_free_blocks().
In the Linux kernel, the following vulnerability has been resolved:
scsi: scsi_transport_sas: Fix error handling in sas_phy_add()
If transport_add_device() fails in sas_phy_add(), the kernel will crash
trying to delete the device in transport_remove_device() called from
sas_remove_host().
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000108
CPU: 61 PID: 42829 Comm: rmmod Kdump: loaded Tainted: G W 6.1.0-rc1+ #173
pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : device_del+0x54/0x3d0
lr : device_del+0x37c/0x3d0
Call trace:
device_del+0x54/0x3d0
attribute_container_class_device_del+0x28/0x38
transport_remove_classdev+0x6c/0x80
attribute_container_device_trigger+0x108/0x110
transport_remove_device+0x28/0x38
sas_phy_delete+0x30/0x60 [scsi_transport_sas]
do_sas_phy_delete+0x6c/0x80 [scsi_transport_sas]
device_for_each_child+0x68/0xb0
sas_remove_children+0x40/0x50 [scsi_transport_sas]
sas_remove_host+0x20/0x38 [scsi_transport_sas]
hisi_sas_remove+0x40/0x68 [hisi_sas_main]
hisi_sas_v2_remove+0x20/0x30 [hisi_sas_v2_hw]
platform_remove+0x2c/0x60
Fix this by checking and handling return value of transport_add_device()
in sas_phy_add().
In the Linux kernel, the following vulnerability has been resolved:
ASoC: core: Fix use-after-free in snd_soc_exit()
KASAN reports a use-after-free:
BUG: KASAN: use-after-free in device_del+0xb5b/0xc60
Read of size 8 at addr ffff888008655050 by task rmmod/387
CPU: 2 PID: 387 Comm: rmmod
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
Call Trace:
<TASK>
dump_stack_lvl+0x79/0x9a
print_report+0x17f/0x47b
kasan_report+0xbb/0xf0
device_del+0xb5b/0xc60
platform_device_del.part.0+0x24/0x200
platform_device_unregister+0x2e/0x40
snd_soc_exit+0xa/0x22 [snd_soc_core]
__do_sys_delete_module.constprop.0+0x34f/0x5b0
do_syscall_64+0x3a/0x90
entry_SYSCALL_64_after_hwframe+0x63/0xcd
...
</TASK>
It's bacause in snd_soc_init(), snd_soc_util_init() is possble to fail,
but its ret is ignored, which makes soc_dummy_dev unregistered twice.
snd_soc_init()
snd_soc_util_init()
platform_device_register_simple(soc_dummy_dev)
platform_driver_register() # fail
platform_device_unregister(soc_dummy_dev)
platform_driver_register() # success
...
snd_soc_exit()
snd_soc_util_exit()
# soc_dummy_dev will be unregistered for second time
To fix it, handle error and stop snd_soc_init() when util_init() fail.
Also clean debugfs when util_init() or driver_register() fail.