Linux: >> Linux Kernel >> 4.14.307 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
fs: dlm: fix race in lowcomms
This patch fixes a race between queue_work() in
_dlm_lowcomms_commit_msg() and srcu_read_unlock(). The queue_work() can
take the final reference of a dlm_msg and so msg->idx can contain
garbage which is signaled by the following warning:
[ 676.237050] ------------[ cut here ]------------
[ 676.237052] WARNING: CPU: 0 PID: 1060 at include/linux/srcu.h:189 dlm_lowcomms_commit_msg+0x41/0x50
[ 676.238945] Modules linked in: dlm_locktorture torture rpcsec_gss_krb5 intel_rapl_msr intel_rapl_common iTCO_wdt iTCO_vendor_support qxl kvm_intel drm_ttm_helper vmw_vsock_virtio_transport kvm vmw_vsock_virtio_transport_common ttm irqbypass crc32_pclmul joydev crc32c_intel serio_raw drm_kms_helper vsock virtio_scsi virtio_console virtio_balloon snd_pcm drm syscopyarea sysfillrect sysimgblt snd_timer fb_sys_fops i2c_i801 lpc_ich snd i2c_smbus soundcore pcspkr
[ 676.244227] CPU: 0 PID: 1060 Comm: lock_torture_wr Not tainted 5.19.0-rc3+ #1546
[ 676.245216] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-2.module+el8.7.0+15506+033991b0 04/01/2014
[ 676.246460] RIP: 0010:dlm_lowcomms_commit_msg+0x41/0x50
[ 676.247132] Code: fe ff ff ff 75 24 48 c7 c6 bd 0f 49 bb 48 c7 c7 38 7c 01 bd e8 00 e7 ca ff 89 de 48 c7 c7 60 78 01 bd e8 42 3d cd ff 5b 5d c3 <0f> 0b eb d8 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48
[ 676.249253] RSP: 0018:ffffa401c18ffc68 EFLAGS: 00010282
[ 676.249855] RAX: 0000000000000001 RBX: 00000000ffff8b76 RCX: 0000000000000006
[ 676.250713] RDX: 0000000000000000 RSI: ffffffffbccf3a10 RDI: ffffffffbcc7b62e
[ 676.251610] RBP: ffffa401c18ffc70 R08: 0000000000000001 R09: 0000000000000001
[ 676.252481] R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000005
[ 676.253421] R13: ffff8b76786ec370 R14: ffff8b76786ec370 R15: ffff8b76786ec480
[ 676.254257] FS: 0000000000000000(0000) GS:ffff8b7777800000(0000) knlGS:0000000000000000
[ 676.255239] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 676.255897] CR2: 00005590205d88b8 CR3: 000000017656c003 CR4: 0000000000770ee0
[ 676.256734] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 676.257567] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 676.258397] PKRU: 55555554
[ 676.258729] Call Trace:
[ 676.259063] <TASK>
[ 676.259354] dlm_midcomms_commit_mhandle+0xcc/0x110
[ 676.259964] queue_bast+0x8b/0xb0
[ 676.260423] grant_pending_locks+0x166/0x1b0
[ 676.261007] _unlock_lock+0x75/0x90
[ 676.261469] unlock_lock.isra.57+0x62/0xa0
[ 676.262009] dlm_unlock+0x21e/0x330
[ 676.262457] ? lock_torture_stats+0x80/0x80 [dlm_locktorture]
[ 676.263183] torture_unlock+0x5a/0x90 [dlm_locktorture]
[ 676.263815] ? preempt_count_sub+0xba/0x100
[ 676.264361] ? complete+0x1d/0x60
[ 676.264777] lock_torture_writer+0xb8/0x150 [dlm_locktorture]
[ 676.265555] kthread+0x10a/0x130
[ 676.266007] ? kthread_complete_and_exit+0x20/0x20
[ 676.266616] ret_from_fork+0x22/0x30
[ 676.267097] </TASK>
[ 676.267381] irq event stamp: 9579855
[ 676.267824] hardirqs last enabled at (9579863): [<ffffffffbb14e6f8>] __up_console_sem+0x58/0x60
[ 676.268896] hardirqs last disabled at (9579872): [<ffffffffbb14e6dd>] __up_console_sem+0x3d/0x60
[ 676.270008] softirqs last enabled at (9579798): [<ffffffffbc200349>] __do_softirq+0x349/0x4c7
[ 676.271438] softirqs last disabled at (9579897): [<ffffffffbb0d54c0>] irq_exit_rcu+0xb0/0xf0
[ 676.272796] ---[ end trace 0000000000000000 ]---
I reproduced this warning with dlm_locktorture test which is currently
not upstream. However this patch fix the issue by make a additional
refcount between dlm_lowcomms_new_msg() and dlm_lowcomms_commit_msg().
In case of the race the kref_put() in dlm_lowcomms_commit_msg() will be
the final put.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_{ldisc,serdev}: check percpu_init_rwsem() failure
syzbot is reporting NULL pointer dereference at hci_uart_tty_close() [1],
for rcu_sync_enter() is called without rcu_sync_init() due to
hci_uart_tty_open() ignoring percpu_init_rwsem() failure.
While we are at it, fix that hci_uart_register_device() ignores
percpu_init_rwsem() failure and hci_uart_unregister_device() does not
call percpu_free_rwsem().
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
RDMA/cxgb4: Fix potential null-ptr-deref in pass_establish()
If get_ep_from_tid() fails to lookup non-NULL value for ep, ep is
dereferenced later regardless of whether it is empty.
This patch adds a simple sanity check to fix the issue.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: do not write dirty data after degenerating to read-only
According to syzbot's report, mark_buffer_dirty() called from
nilfs_segctor_do_construct() outputs a warning with some patterns after
nilfs2 detects metadata corruption and degrades to read-only mode.
After such read-only degeneration, page cache data may be cleared through
nilfs_clear_dirty_page() which may also clear the uptodate flag for their
buffer heads. However, even after the degeneration, log writes are still
performed by unmount processing etc., which causes mark_buffer_dirty() to
be called for buffer heads without the "uptodate" flag and causes the
warning.
Since any writes should not be done to a read-only file system in the
first place, this fixes the warning in mark_buffer_dirty() by letting
nilfs_segctor_do_construct() abort early if in read-only mode.
This also changes the retry check of nilfs_segctor_write_out() to avoid
unnecessary log write retries if it detects -EROFS that
nilfs_segctor_do_construct() returned.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
lwt: Fix return values of BPF xmit ops
BPF encap ops can return different types of positive values, such like
NET_RX_DROP, NET_XMIT_CN, NETDEV_TX_BUSY, and so on, from function
skb_do_redirect and bpf_lwt_xmit_reroute. At the xmit hook, such return
values would be treated implicitly as LWTUNNEL_XMIT_CONTINUE in
ip(6)_finish_output2. When this happens, skbs that have been freed would
continue to the neighbor subsystem, causing use-after-free bug and
kernel crashes.
To fix the incorrect behavior, skb_do_redirect return values can be
simply discarded, the same as tc-egress behavior. On the other hand,
bpf_lwt_xmit_reroute returns useful errors to local senders, e.g. PMTU
information. Thus convert its return values to avoid the conflict with
LWTUNNEL_XMIT_CONTINUE.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
i2c: mux: reg: check return value after calling platform_get_resource()
It will cause null-ptr-deref in resource_size(), if platform_get_resource()
returns NULL, move calling resource_size() after devm_ioremap_resource() that
will check 'res' to avoid null-ptr-deref.
And use devm_platform_get_and_ioremap_resource() to simplify code.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dsi: fix memory corruption with too many bridges
Add the missing sanity check on the bridge counter to avoid corrupting
data beyond the fixed-sized bridge array in case there are ever more
than eight bridges.
Patchwork: https://patchwork.freedesktop.org/patch/502668/
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
net: sched: sfb: fix null pointer access issue when sfb_init() fails
When the default qdisc is sfb, if the qdisc of dev_queue fails to be
inited during mqprio_init(), sfb_reset() is invoked to clear resources.
In this case, the q->qdisc is NULL, and it will cause gpf issue.
The process is as follows:
qdisc_create_dflt()
sfb_init()
tcf_block_get() --->failed, q->qdisc is NULL
...
qdisc_put()
...
sfb_reset()
qdisc_reset(q->qdisc) --->q->qdisc is NULL
ops = qdisc->ops
The following is the Call Trace information:
general protection fault, probably for non-canonical address
0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f]
RIP: 0010:qdisc_reset+0x2b/0x6f0
Call Trace:
<TASK>
sfb_reset+0x37/0xd0
qdisc_reset+0xed/0x6f0
qdisc_destroy+0x82/0x4c0
qdisc_put+0x9e/0xb0
qdisc_create_dflt+0x2c3/0x4a0
mqprio_init+0xa71/0x1760
qdisc_create+0x3eb/0x1000
tc_modify_qdisc+0x408/0x1720
rtnetlink_rcv_msg+0x38e/0xac0
netlink_rcv_skb+0x12d/0x3a0
netlink_unicast+0x4a2/0x740
netlink_sendmsg+0x826/0xcc0
sock_sendmsg+0xc5/0x100
____sys_sendmsg+0x583/0x690
___sys_sendmsg+0xe8/0x160
__sys_sendmsg+0xbf/0x160
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f2164122d04
</TASK>
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
brcmfmac: return error when getting invalid max_flowrings from dongle
When firmware hit trap at initialization, host will read abnormal
max_flowrings number from dongle, and it will cause kernel panic when
doing iowrite to initialize dongle ring.
To detect this error at early stage, we directly return error when getting
invalid max_flowrings(>256).
CVSS Score
4.2
EPSS Score
0.0
Published
2025-09-17
In the Linux kernel, the following vulnerability has been resolved:
pstore/ram: Check start of empty przs during init
After commit 30696378f68a ("pstore/ram: Do not treat empty buffers as
valid"), initialization would assume a prz was valid after seeing that
the buffer_size is zero (regardless of the buffer start position). This
unchecked start value means it could be outside the bounds of the buffer,
leading to future access panics when written to:
sysdump_panic_event+0x3b4/0x5b8
atomic_notifier_call_chain+0x54/0x90
panic+0x1c8/0x42c
die+0x29c/0x2a8
die_kernel_fault+0x68/0x78
__do_kernel_fault+0x1c4/0x1e0
do_bad_area+0x40/0x100
do_translation_fault+0x68/0x80
do_mem_abort+0x68/0xf8
el1_da+0x1c/0xc0
__raw_writeb+0x38/0x174
__memcpy_toio+0x40/0xac
persistent_ram_update+0x44/0x12c
persistent_ram_write+0x1a8/0x1b8
ramoops_pstore_write+0x198/0x1e8
pstore_console_write+0x94/0xe0
...
To avoid this, also check if the prz start is 0 during the initialization
phase. If not, the next prz sanity check case will discover it (start >
size) and zap the buffer back to a sane state.
[kees: update commit log with backtrace and clarifications]
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-16