Linux: >> Linux Kernel >> 3.12.41 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix warning in 'ext4_da_release_space'
Syzkaller report issue as follows:
EXT4-fs (loop0): Free/Dirty block details
EXT4-fs (loop0): free_blocks=0
EXT4-fs (loop0): dirty_blocks=0
EXT4-fs (loop0): Block reservation details
EXT4-fs (loop0): i_reserved_data_blocks=0
EXT4-fs warning (device loop0): ext4_da_release_space:1527: ext4_da_release_space: ino 18, to_free 1 with only 0 reserved data blocks
------------[ cut here ]------------
WARNING: CPU: 0 PID: 92 at fs/ext4/inode.c:1528 ext4_da_release_space+0x25e/0x370 fs/ext4/inode.c:1524
Modules linked in:
CPU: 0 PID: 92 Comm: kworker/u4:4 Not tainted 6.0.0-syzkaller-09423-g493ffd6605b2 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Workqueue: writeback wb_workfn (flush-7:0)
RIP: 0010:ext4_da_release_space+0x25e/0x370 fs/ext4/inode.c:1528
RSP: 0018:ffffc900015f6c90 EFLAGS: 00010296
RAX: 42215896cd52ea00 RBX: 0000000000000000 RCX: 42215896cd52ea00
RDX: 0000000000000000 RSI: 0000000080000001 RDI: 0000000000000000
RBP: 1ffff1100e907d96 R08: ffffffff816aa79d R09: fffff520002bece5
R10: fffff520002bece5 R11: 1ffff920002bece4 R12: ffff888021fd2000
R13: ffff88807483ecb0 R14: 0000000000000001 R15: ffff88807483e740
FS: 0000000000000000(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555569ba628 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ext4_es_remove_extent+0x1ab/0x260 fs/ext4/extents_status.c:1461
mpage_release_unused_pages+0x24d/0xef0 fs/ext4/inode.c:1589
ext4_writepages+0x12eb/0x3be0 fs/ext4/inode.c:2852
do_writepages+0x3c3/0x680 mm/page-writeback.c:2469
__writeback_single_inode+0xd1/0x670 fs/fs-writeback.c:1587
writeback_sb_inodes+0xb3b/0x18f0 fs/fs-writeback.c:1870
wb_writeback+0x41f/0x7b0 fs/fs-writeback.c:2044
wb_do_writeback fs/fs-writeback.c:2187 [inline]
wb_workfn+0x3cb/0xef0 fs/fs-writeback.c:2227
process_one_work+0x877/0xdb0 kernel/workqueue.c:2289
worker_thread+0xb14/0x1330 kernel/workqueue.c:2436
kthread+0x266/0x300 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
</TASK>
Above issue may happens as follows:
ext4_da_write_begin
ext4_create_inline_data
ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
__ext4_ioctl
ext4_ext_migrate -> will lead to eh->eh_entries not zero, and set extent flag
ext4_da_write_begin
ext4_da_convert_inline_data_to_extent
ext4_da_write_inline_data_begin
ext4_da_map_blocks
ext4_insert_delayed_block
if (!ext4_es_scan_clu(inode, &ext4_es_is_delonly, lblk))
if (!ext4_es_scan_clu(inode, &ext4_es_is_mapped, lblk))
ext4_clu_mapped(inode, EXT4_B2C(sbi, lblk)); -> will return 1
allocated = true;
ext4_es_insert_delayed_block(inode, lblk, allocated);
ext4_writepages
mpage_map_and_submit_extent(handle, &mpd, &give_up_on_write); -> return -ENOSPC
mpage_release_unused_pages(&mpd, give_up_on_write); -> give_up_on_write == 1
ext4_es_remove_extent
ext4_da_release_space(inode, reserved);
if (unlikely(to_free > ei->i_reserved_data_blocks))
-> to_free == 1 but ei->i_reserved_data_blocks == 0
-> then trigger warning as above
To solve above issue, forbid inode do migrate which has inline data.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
In the Linux kernel, the following vulnerability has been resolved:
ipv6: addrlabel: fix infoleak when sending struct ifaddrlblmsg to network
When copying a `struct ifaddrlblmsg` to the network, __ifal_reserved
remained uninitialized, resulting in a 1-byte infoleak:
BUG: KMSAN: kernel-network-infoleak in __netdev_start_xmit ./include/linux/netdevice.h:4841
__netdev_start_xmit ./include/linux/netdevice.h:4841
netdev_start_xmit ./include/linux/netdevice.h:4857
xmit_one net/core/dev.c:3590
dev_hard_start_xmit+0x1dc/0x800 net/core/dev.c:3606
__dev_queue_xmit+0x17e8/0x4350 net/core/dev.c:4256
dev_queue_xmit ./include/linux/netdevice.h:3009
__netlink_deliver_tap_skb net/netlink/af_netlink.c:307
__netlink_deliver_tap+0x728/0xad0 net/netlink/af_netlink.c:325
netlink_deliver_tap net/netlink/af_netlink.c:338
__netlink_sendskb net/netlink/af_netlink.c:1263
netlink_sendskb+0x1d9/0x200 net/netlink/af_netlink.c:1272
netlink_unicast+0x56d/0xf50 net/netlink/af_netlink.c:1360
nlmsg_unicast ./include/net/netlink.h:1061
rtnl_unicast+0x5a/0x80 net/core/rtnetlink.c:758
ip6addrlbl_get+0xfad/0x10f0 net/ipv6/addrlabel.c:628
rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082
...
Uninit was created at:
slab_post_alloc_hook+0x118/0xb00 mm/slab.h:742
slab_alloc_node mm/slub.c:3398
__kmem_cache_alloc_node+0x4f2/0x930 mm/slub.c:3437
__do_kmalloc_node mm/slab_common.c:954
__kmalloc_node_track_caller+0x117/0x3d0 mm/slab_common.c:975
kmalloc_reserve net/core/skbuff.c:437
__alloc_skb+0x27a/0xab0 net/core/skbuff.c:509
alloc_skb ./include/linux/skbuff.h:1267
nlmsg_new ./include/net/netlink.h:964
ip6addrlbl_get+0x490/0x10f0 net/ipv6/addrlabel.c:608
rtnetlink_rcv_msg+0xb33/0x1570 net/core/rtnetlink.c:6082
netlink_rcv_skb+0x299/0x550 net/netlink/af_netlink.c:2540
rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:6109
netlink_unicast_kernel net/netlink/af_netlink.c:1319
netlink_unicast+0x9ab/0xf50 net/netlink/af_netlink.c:1345
netlink_sendmsg+0xebc/0x10f0 net/netlink/af_netlink.c:1921
...
This patch ensures that the reserved field is always initialized.
CVSS Score
7.1
EPSS Score
0.001
Published
2025-05-01
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>
CVSS Score
7.1
EPSS Score
0.0
Published
2025-05-01
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().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
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().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
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.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-05-01
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")
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01
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.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-05-01