Linux: >> Linux Kernel >> 6.1.144 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
x86/mce: use is_copy_from_user() to determine copy-from-user context
Patch series "mm/hwpoison: Fix regressions in memory failure handling",
v4.
## 1. What am I trying to do:
This patchset resolves two critical regressions related to memory failure
handling that have appeared in the upstream kernel since version 5.17, as
compared to 5.10 LTS.
- copyin case: poison found in user page while kernel copying from user space
- instr case: poison found while instruction fetching in user space
## 2. What is the expected outcome and why
- For copyin case:
Kernel can recover from poison found where kernel is doing get_user() or
copy_from_user() if those places get an error return and the kernel return
-EFAULT to the process instead of crashing. More specifily, MCE handler
checks the fixup handler type to decide whether an in kernel #MC can be
recovered. When EX_TYPE_UACCESS is found, the PC jumps to recovery code
specified in _ASM_EXTABLE_FAULT() and return a -EFAULT to user space.
- For instr case:
If a poison found while instruction fetching in user space, full recovery
is possible. User process takes #PF, Linux allocates a new page and fills
by reading from storage.
## 3. What actually happens and why
- For copyin case: kernel panic since v5.17
Commit 4c132d1d844a ("x86/futex: Remove .fixup usage") introduced a new
extable fixup type, EX_TYPE_EFAULT_REG, and later patches updated the
extable fixup type for copy-from-user operations, changing it from
EX_TYPE_UACCESS to EX_TYPE_EFAULT_REG. It breaks previous EX_TYPE_UACCESS
handling when posion found in get_user() or copy_from_user().
- For instr case: user process is killed by a SIGBUS signal due to #CMCI
and #MCE race
When an uncorrected memory error is consumed there is a race between the
CMCI from the memory controller reporting an uncorrected error with a UCNA
signature, and the core reporting and SRAR signature machine check when
the data is about to be consumed.
### Background: why *UN*corrected errors tied to *C*MCI in Intel platform [1]
Prior to Icelake memory controllers reported patrol scrub events that
detected a previously unseen uncorrected error in memory by signaling a
broadcast machine check with an SRAO (Software Recoverable Action
Optional) signature in the machine check bank. This was overkill because
it's not an urgent problem that no core is on the verge of consuming that
bad data. It's also found that multi SRAO UCE may cause nested MCE
interrupts and finally become an IERR.
Hence, Intel downgrades the machine check bank signature of patrol scrub
from SRAO to UCNA (Uncorrected, No Action required), and signal changed to
#CMCI. Just to add to the confusion, Linux does take an action (in
uc_decode_notifier()) to try to offline the page despite the UC*NA*
signature name.
### Background: why #CMCI and #MCE race when poison is consuming in
Intel platform [1]
Having decided that CMCI/UCNA is the best action for patrol scrub errors,
the memory controller uses it for reads too. But the memory controller is
executing asynchronously from the core, and can't tell the difference
between a "real" read and a speculative read. So it will do CMCI/UCNA if
an error is found in any read.
Thus:
1) Core is clever and thinks address A is needed soon, issues a
speculative read.
2) Core finds it is going to use address A soon after sending the read
request
3) The CMCI from the memory controller is in a race with MCE from the
core that will soon try to retire the load from address A.
Quite often (because speculation has got better) the CMCI from the memory
controller is delivered before the core is committed to the instruction
reading address A, so the interrupt is taken, and Linux offlines the page
(marking it as poison).
## Why user process is killed for instr case
Commit 046545a661af ("mm/hwpoison: fix error page recovered but reported
"not
---truncated---
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-18
In the Linux kernel, the following vulnerability has been resolved:
md/raid10: wait barrier before returning discard request with REQ_NOWAIT
raid10_handle_discard should wait barrier before returning a discard bio
which has REQ_NOWAIT. And there is no need to print warning calltrace
if a discard bio has REQ_NOWAIT flag. Quality engineer usually checks
dmesg and reports error if dmesg has warning/error calltrace.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-18
In the Linux kernel, the following vulnerability has been resolved:
jfs: reject on-disk inodes of an unsupported type
Syzbot has reported the following BUG:
kernel BUG at fs/inode.c:668!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
CPU: 3 UID: 0 PID: 139 Comm: jfsCommit Not tainted 6.12.0-rc4-syzkaller-00085-g4e46774408d9 #0
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
RIP: 0010:clear_inode+0x168/0x190
Code: 4c 89 f7 e8 ba fe e5 ff e9 61 ff ff ff 44 89 f1 80 e1 07 80 c1 03 38 c1 7c c1 4c 89 f7 e8 90 ff e5 ff eb b7
0b e8 01 5d 7f ff 90 0f 0b e8 f9 5c 7f ff 90 0f 0b e8 f1 5c 7f
RSP: 0018:ffffc900027dfae8 EFLAGS: 00010093
RAX: ffffffff82157a87 RBX: 0000000000000001 RCX: ffff888104d4b980
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900027dfc90 R08: ffffffff82157977 R09: fffff520004fbf38
R10: dffffc0000000000 R11: fffff520004fbf38 R12: dffffc0000000000
R13: ffff88811315bc00 R14: ffff88811315bda8 R15: ffff88811315bb80
FS: 0000000000000000(0000) GS:ffff888135f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005565222e0578 CR3: 0000000026ef0000 CR4: 00000000000006f0
Call Trace:
<TASK>
? __die_body+0x5f/0xb0
? die+0x9e/0xc0
? do_trap+0x15a/0x3a0
? clear_inode+0x168/0x190
? do_error_trap+0x1dc/0x2c0
? clear_inode+0x168/0x190
? __pfx_do_error_trap+0x10/0x10
? report_bug+0x3cd/0x500
? handle_invalid_op+0x34/0x40
? clear_inode+0x168/0x190
? exc_invalid_op+0x38/0x50
? asm_exc_invalid_op+0x1a/0x20
? clear_inode+0x57/0x190
? clear_inode+0x167/0x190
? clear_inode+0x168/0x190
? clear_inode+0x167/0x190
jfs_evict_inode+0xb5/0x440
? __pfx_jfs_evict_inode+0x10/0x10
evict+0x4ea/0x9b0
? __pfx_evict+0x10/0x10
? iput+0x713/0xa50
txUpdateMap+0x931/0xb10
? __pfx_txUpdateMap+0x10/0x10
jfs_lazycommit+0x49a/0xb80
? _raw_spin_unlock_irqrestore+0x8f/0x140
? lockdep_hardirqs_on+0x99/0x150
? __pfx_jfs_lazycommit+0x10/0x10
? __pfx_default_wake_function+0x10/0x10
? __kthread_parkme+0x169/0x1d0
? __pfx_jfs_lazycommit+0x10/0x10
kthread+0x2f2/0x390
? __pfx_jfs_lazycommit+0x10/0x10
? __pfx_kthread+0x10/0x10
ret_from_fork+0x4d/0x80
? __pfx_kthread+0x10/0x10
ret_from_fork_asm+0x1a/0x30
</TASK>
This happens when 'clear_inode()' makes an attempt to finalize an underlying
JFS inode of unknown type. According to JFS layout description from
https://jfs.sourceforge.net/project/pub/jfslayout.pdf, inode types from 5 to
15 are reserved for future extensions and should not be encountered on a valid
filesystem. So add an extra check for valid inode type in 'copy_from_dinode()'.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-18
In the Linux kernel, the following vulnerability has been resolved:
sfc: fix NULL dereferences in ef100_process_design_param()
Since cited commit, ef100_probe_main() and hence also
ef100_check_design_params() run before efx->net_dev is created;
consequently, we cannot netif_set_tso_max_size() or _segs() at this
point.
Move those netif calls to ef100_probe_netdev(), and also replace
netif_err within the design params code with pci_err.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-18
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: Clear affinity hint before calling ath11k_pcic_free_irq() in error path
If a shared IRQ is used by the driver due to platform limitation, then the
IRQ affinity hint is set right after the allocation of IRQ vectors in
ath11k_pci_alloc_msi(). This does no harm unless one of the functions
requesting the IRQ fails and attempt to free the IRQ. This results in the
below warning:
WARNING: CPU: 7 PID: 349 at kernel/irq/manage.c:1929 free_irq+0x278/0x29c
Call trace:
free_irq+0x278/0x29c
ath11k_pcic_free_irq+0x70/0x10c [ath11k]
ath11k_pci_probe+0x800/0x820 [ath11k_pci]
local_pci_probe+0x40/0xbc
The warning is due to not clearing the affinity hint before freeing the
IRQs.
So to fix this issue, clear the IRQ affinity hint before calling
ath11k_pcic_free_irq() in the error path. The affinity will be cleared once
again further down the error path due to code organization, but that does
no harm.
Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-05266-QCAHSTSWPLZ_V2_TO_X86-1
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid panic once fallocation fails for pinfile
syzbot reports a f2fs bug as below:
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:2746!
CPU: 0 UID: 0 PID: 5323 Comm: syz.0.0 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0
RIP: 0010:get_new_segment fs/f2fs/segment.c:2746 [inline]
RIP: 0010:new_curseg+0x1f52/0x1f70 fs/f2fs/segment.c:2876
Call Trace:
<TASK>
__allocate_new_segment+0x1ce/0x940 fs/f2fs/segment.c:3210
f2fs_allocate_new_section fs/f2fs/segment.c:3224 [inline]
f2fs_allocate_pinning_section+0xfa/0x4e0 fs/f2fs/segment.c:3238
f2fs_expand_inode_data+0x696/0xca0 fs/f2fs/file.c:1830
f2fs_fallocate+0x537/0xa10 fs/f2fs/file.c:1940
vfs_fallocate+0x569/0x6e0 fs/open.c:327
do_vfs_ioctl+0x258c/0x2e40 fs/ioctl.c:885
__do_sys_ioctl fs/ioctl.c:904 [inline]
__se_sys_ioctl+0x80/0x170 fs/ioctl.c:892
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Concurrent pinfile allocation may run out of free section, result in
panic in get_new_segment(), let's expand pin_sem lock coverage to
include f2fs_gc(), so that we can make sure to reclaim enough free
space for following allocation.
In addition, do below changes to enhance error path handling:
- call f2fs_bug_on() only in non-pinfile allocation path in
get_new_segment().
- call reset_curseg_fields() to reset all fields of curseg in
new_curseg()
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
dlm: prevent NPD when writing a positive value to event_done
do_uevent returns the value written to event_done. In case it is a
positive value, new_lockspace would undo all the work, and lockspace
would not be set. __dlm_new_lockspace, however, would treat that
positive value as a success due to commit 8511a2728ab8 ("dlm: fix use
count with multiple joins").
Down the line, device_create_lockspace would pass that NULL lockspace to
dlm_find_lockspace_local, leading to a NULL pointer dereference.
Treating such positive values as successes prevents the problem. Given
this has been broken for so long, this is unlikely to break userspace
expectations.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
f2fs: quota: fix to avoid warning in dquot_writeback_dquots()
F2FS-fs (dm-59): checkpoint=enable has some unwritten data.
------------[ cut here ]------------
WARNING: CPU: 6 PID: 8013 at fs/quota/dquot.c:691 dquot_writeback_dquots+0x2fc/0x308
pc : dquot_writeback_dquots+0x2fc/0x308
lr : f2fs_quota_sync+0xcc/0x1c4
Call trace:
dquot_writeback_dquots+0x2fc/0x308
f2fs_quota_sync+0xcc/0x1c4
f2fs_write_checkpoint+0x3d4/0x9b0
f2fs_issue_checkpoint+0x1bc/0x2c0
f2fs_sync_fs+0x54/0x150
f2fs_do_sync_file+0x2f8/0x814
__f2fs_ioctl+0x1960/0x3244
f2fs_ioctl+0x54/0xe0
__arm64_sys_ioctl+0xa8/0xe4
invoke_syscall+0x58/0x114
checkpoint and f2fs_remount may race as below, resulting triggering warning
in dquot_writeback_dquots().
atomic write remount
- do_remount
- down_write(&sb->s_umount);
- f2fs_remount
- ioctl
- f2fs_do_sync_file
- f2fs_sync_fs
- f2fs_write_checkpoint
- block_operations
- locked = down_read_trylock(&sbi->sb->s_umount)
: fail to lock due to the write lock was held by remount
- up_write(&sb->s_umount);
- f2fs_quota_sync
- dquot_writeback_dquots
- WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount))
: trigger warning because s_umount lock was unlocked by remount
If checkpoint comes from mount/umount/remount/freeze/quotactl, caller of
checkpoint has already held s_umount lock, calling dquot_writeback_dquots()
in the context should be safe.
So let's record task to sbi->umount_lock_holder, so that checkpoint can
know whether the lock has held in the context or not by checking current
w/ it.
In addition, in order to not misrepresent caller of checkpoint, we should
not allow to trigger async checkpoint for those callers: mount/umount/remount/
freeze/quotactl.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: update channel list in reg notifier instead reg worker
Currently when ath11k gets a new channel list, it will be processed
according to the following steps:
1. update new channel list to cfg80211 and queue reg_work.
2. cfg80211 handles new channel list during reg_work.
3. update cfg80211's handled channel list to firmware by
ath11k_reg_update_chan_list().
But ath11k will immediately execute step 3 after reg_work is just
queued. Since step 2 is asynchronous, cfg80211 may not have completed
handling the new channel list, which may leading to an out-of-bounds
write error:
BUG: KASAN: slab-out-of-bounds in ath11k_reg_update_chan_list
Call Trace:
ath11k_reg_update_chan_list+0xbfe/0xfe0 [ath11k]
kfree+0x109/0x3a0
ath11k_regd_update+0x1cf/0x350 [ath11k]
ath11k_regd_update_work+0x14/0x20 [ath11k]
process_one_work+0xe35/0x14c0
Should ensure step 2 is completely done before executing step 3. Thus
Wen raised patch[1]. When flag NL80211_REGDOM_SET_BY_DRIVER is set,
cfg80211 will notify ath11k after step 2 is done.
So enable the flag NL80211_REGDOM_SET_BY_DRIVER then cfg80211 will
notify ath11k after step 2 is done. At this time, there will be no
KASAN bug during the execution of the step 3.
[1] https://patchwork.kernel.org/project/linux-wireless/patch/20230201065313.27203-1-quic_wgong@quicinc.com/
Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3
CVSS Score
7.8
EPSS Score
0.001
Published
2025-04-16
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix out-of-bound read in ext4_xattr_inode_dec_ref_all()
There's issue as follows:
BUG: KASAN: use-after-free in ext4_xattr_inode_dec_ref_all+0x6ff/0x790
Read of size 4 at addr ffff88807b003000 by task syz-executor.0/15172
CPU: 3 PID: 15172 Comm: syz-executor.0
Call Trace:
__dump_stack lib/dump_stack.c:82 [inline]
dump_stack+0xbe/0xfd lib/dump_stack.c:123
print_address_description.constprop.0+0x1e/0x280 mm/kasan/report.c:400
__kasan_report.cold+0x6c/0x84 mm/kasan/report.c:560
kasan_report+0x3a/0x50 mm/kasan/report.c:585
ext4_xattr_inode_dec_ref_all+0x6ff/0x790 fs/ext4/xattr.c:1137
ext4_xattr_delete_inode+0x4c7/0xda0 fs/ext4/xattr.c:2896
ext4_evict_inode+0xb3b/0x1670 fs/ext4/inode.c:323
evict+0x39f/0x880 fs/inode.c:622
iput_final fs/inode.c:1746 [inline]
iput fs/inode.c:1772 [inline]
iput+0x525/0x6c0 fs/inode.c:1758
ext4_orphan_cleanup fs/ext4/super.c:3298 [inline]
ext4_fill_super+0x8c57/0xba40 fs/ext4/super.c:5300
mount_bdev+0x355/0x410 fs/super.c:1446
legacy_get_tree+0xfe/0x220 fs/fs_context.c:611
vfs_get_tree+0x8d/0x2f0 fs/super.c:1576
do_new_mount fs/namespace.c:2983 [inline]
path_mount+0x119a/0x1ad0 fs/namespace.c:3316
do_mount+0xfc/0x110 fs/namespace.c:3329
__do_sys_mount fs/namespace.c:3540 [inline]
__se_sys_mount+0x219/0x2e0 fs/namespace.c:3514
do_syscall_64+0x33/0x40 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x67/0xd1
Memory state around the buggy address:
ffff88807b002f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff88807b002f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88807b003000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffff88807b003080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffff88807b003100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
Above issue happens as ext4_xattr_delete_inode() isn't check xattr
is valid if xattr is in inode.
To solve above issue call xattr_check_inode() check if xattr if valid
in inode. In fact, we can directly verify in ext4_iget_extra_inode(),
so that there is no divergent verification.
CVSS Score
7.1
EPSS Score
0.001
Published
2025-04-16