Linux: >> Linux Kernel >> 6.1.16 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
rcu/rcuscale: Stop kfree_scale_thread thread(s) after unloading rcuscale
Running the 'kfree_rcu_test' test case [1] results in a splat [2].
The root cause is the kfree_scale_thread thread(s) continue running
after unloading the rcuscale module. This commit fixes that isue by
invoking kfree_scale_cleanup() from rcu_scale_cleanup() when removing
the rcuscale module.
[1] modprobe rcuscale kfree_rcu_test=1
// After some time
rmmod rcuscale
rmmod torture
[2] BUG: unable to handle page fault for address: ffffffffc0601a87
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD 11de4f067 P4D 11de4f067 PUD 11de51067 PMD 112f4d067 PTE 0
Oops: 0010 [#1] PREEMPT SMP NOPTI
CPU: 1 PID: 1798 Comm: kfree_scale_thr Not tainted 6.3.0-rc1-rcu+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015
RIP: 0010:0xffffffffc0601a87
Code: Unable to access opcode bytes at 0xffffffffc0601a5d.
RSP: 0018:ffffb25bc2e57e18 EFLAGS: 00010297
RAX: 0000000000000000 RBX: ffffffffc061f0b6 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff962fd0de RDI: ffffffff962fd0de
RBP: ffffb25bc2e57ea8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: 000000000000000a R15: 00000000001c1dbe
FS: 0000000000000000(0000) GS:ffff921fa2200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffc0601a5d CR3: 000000011de4c006 CR4: 0000000000370ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
? kvfree_call_rcu+0xf0/0x3a0
? kthread+0xf3/0x120
? kthread_complete_and_exit+0x20/0x20
? ret_from_fork+0x1f/0x30
</TASK>
Modules linked in: rfkill sunrpc ... [last unloaded: torture]
CR2: ffffffffc0601a87
---[ end trace 0000000000000000 ]---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none
After grabbing q->sysfs_lock, q->elevator may become NULL because of
elevator switch.
Fix the NULL dereference on q->elevator by checking it with lock.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
fs/ntfs3: Fix null-ptr-deref on inode->i_op in ntfs_lookup()
Syzbot reported a null-ptr-deref bug:
ntfs3: loop0: Different NTFS' sector size (1024) and media sector size
(512)
ntfs3: loop0: Mark volume as dirty due to NTFS errors
general protection fault, probably for non-canonical address
0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
RIP: 0010:d_flags_for_inode fs/dcache.c:1980 [inline]
RIP: 0010:__d_add+0x5ce/0x800 fs/dcache.c:2796
Call Trace:
<TASK>
d_splice_alias+0x122/0x3b0 fs/dcache.c:3191
lookup_open fs/namei.c:3391 [inline]
open_last_lookups fs/namei.c:3481 [inline]
path_openat+0x10e6/0x2df0 fs/namei.c:3688
do_filp_open+0x264/0x4f0 fs/namei.c:3718
do_sys_openat2+0x124/0x4e0 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_open fs/open.c:1334 [inline]
__se_sys_open fs/open.c:1330 [inline]
__x64_sys_open+0x221/0x270 fs/open.c:1330
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
If the MFT record of ntfs inode is not a base record, inode->i_op can be
NULL. And a null-ptr-deref may happen:
ntfs_lookup()
dir_search_u() # inode->i_op is set to NULL
d_splice_alias()
__d_add()
d_flags_for_inode() # inode->i_op->get_link null-ptr-deref
Fix this by adding a Check on inode->i_op before calling the
d_splice_alias() function.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
sctp: check send stream number after wait_for_sndbuf
This patch fixes a corner case where the asoc out stream count may change
after wait_for_sndbuf.
When the main thread in the client starts a connection, if its out stream
count is set to N while the in stream count in the server is set to N - 2,
another thread in the client keeps sending the msgs with stream number
N - 1, and waits for sndbuf before processing INIT_ACK.
However, after processing INIT_ACK, the out stream count in the client is
shrunk to N - 2, the same to the in stream count in the server. The crash
occurs when the thread waiting for sndbuf is awake and sends the msg in a
non-existing stream(N - 1), the call trace is as below:
KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f]
Call Trace:
<TASK>
sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline]
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline]
sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170
sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163
sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868
sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026
inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825
sock_sendmsg_nosec net/socket.c:722 [inline]
sock_sendmsg+0xde/0x190 net/socket.c:745
The fix is to add an unlikely check for the send stream number after the
thread wakes up from the wait_for_sndbuf.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
drivers: staging: rtl8723bs: Fix locking in _rtw_join_timeout_handler()
Commit 041879b12ddb ("drivers: staging: rtl8192bs: Fix deadlock in
rtw_joinbss_event_prehandle()") besides fixing the deadlock also
modified _rtw_join_timeout_handler() to use spin_[un]lock_irq()
instead of spin_[un]lock_bh().
_rtw_join_timeout_handler() calls rtw_do_join() which takes
pmlmepriv->scanned_queue.lock using spin_[un]lock_bh(). This
spin_unlock_bh() call re-enables softirqs which triggers an oops in
kernel/softirq.c: __local_bh_enable_ip() when it calls
lockdep_assert_irqs_enabled():
[ 244.506087] WARNING: CPU: 2 PID: 0 at kernel/softirq.c:376 __local_bh_enable_ip+0xa6/0x100
...
[ 244.509022] Call Trace:
[ 244.509048] <IRQ>
[ 244.509100] _rtw_join_timeout_handler+0x134/0x170 [r8723bs]
[ 244.509468] ? __pfx__rtw_join_timeout_handler+0x10/0x10 [r8723bs]
[ 244.509772] ? __pfx__rtw_join_timeout_handler+0x10/0x10 [r8723bs]
[ 244.510076] call_timer_fn+0x95/0x2a0
[ 244.510200] __run_timers.part.0+0x1da/0x2d0
This oops is causd by the switch to spin_[un]lock_irq() which disables
the IRQs for the entire duration of _rtw_join_timeout_handler().
Disabling the IRQs is not necessary since all code taking this lock
runs from either user contexts or from softirqs, switch back to
spin_[un]lock_bh() to fix this.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
ext4: add bounds checking in get_max_inline_xattr_value_size()
Normally the extended attributes in the inode body would have been
checked when the inode is first opened, but if someone is writing to
the block device while the file system is mounted, it's possible for
the inode table to get corrupted. Add bounds checking to avoid
reading beyond the end of allocated memory if this happens.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
RDMA/mlx5: Return the firmware result upon destroying QP/RQ
Previously when destroying a QP/RQ, the result of the firmware
destruction function was ignored and upper layers weren't informed
about the failure.
Which in turn could lead to various problems since when upper layer
isn't aware of the failure it continues its operation thinking that the
related QP/RQ was successfully destroyed while it actually wasn't,
which could lead to the below kernel WARN.
Currently, we return the correct firmware destruction status to upper
layers which in case of the RQ would be mlx5_ib_destroy_wq() which
was already capable of handling RQ destruction failure or in case of
a QP to destroy_qp_common(), which now would actually warn upon qp
destruction failure.
WARNING: CPU: 3 PID: 995 at drivers/infiniband/core/rdma_core.c:940 uverbs_destroy_ufile_hw+0xcb/0xe0 [ib_uverbs]
Modules linked in: xt_conntrack xt_MASQUERADE nf_conntrack_netlink nfnetlink xt_addrtype iptable_nat nf_nat br_netfilter rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi rdma_cm ib_umad ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core overlay mlx5_core fuse
CPU: 3 PID: 995 Comm: python3 Not tainted 5.16.0-rc5+ #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:uverbs_destroy_ufile_hw+0xcb/0xe0 [ib_uverbs]
Code: 41 5c 41 5d 41 5e e9 44 34 f0 e0 48 89 df e8 4c 77 ff ff 49 8b 86 10 01 00 00 48 85 c0 74 a1 4c 89 e7 ff d0 eb 9a 0f 0b eb c1 <0f> 0b be 04 00 00 00 48 89 df e8 b6 f6 ff ff e9 75 ff ff ff 90 0f
RSP: 0018:ffff8881533e3e78 EFLAGS: 00010287
RAX: ffff88811b2cf3e0 RBX: ffff888106209700 RCX: 0000000000000000
RDX: ffff888106209780 RSI: ffff8881533e3d30 RDI: ffff888109b101a0
RBP: 0000000000000001 R08: ffff888127cb381c R09: 0de9890000000009
R10: ffff888127cb3800 R11: 0000000000000000 R12: ffff888106209780
R13: ffff888106209750 R14: ffff888100f20660 R15: 0000000000000000
FS: 00007f8be353b740(0000) GS:ffff88852c980000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8bd5b117c0 CR3: 000000012cd8a004 CR4: 0000000000370ea0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
ib_uverbs_close+0x1a/0x90 [ib_uverbs]
__fput+0x82/0x230
task_work_run+0x59/0x90
exit_to_user_mode_prepare+0x138/0x140
syscall_exit_to_user_mode+0x1d/0x50
? __x64_sys_close+0xe/0x40
do_syscall_64+0x4a/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f8be3ae0abb
Code: 03 00 00 00 0f 05 48 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 83 43 f9 ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 c1 43 f9 ff 8b 44
RSP: 002b:00007ffdb51909c0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000557bb7f7c020 RCX: 00007f8be3ae0abb
RDX: 0000557bb7c74010 RSI: 0000557bb7f14ca0 RDI: 0000000000000005
RBP: 0000557bb7fbd598 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000557bb7fbd5b8
R13: 0000557bb7fbd5a8 R14: 0000000000001000 R15: 0000557bb7f7c020
</TASK>
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
usb: cdns3: Put the cdns set active part outside the spin lock
The device may be scheduled during the resume process,
so this cannot appear in atomic operations. Since
pm_runtime_set_active will resume suppliers, put set
active outside the spin lock, which is only used to
protect the struct cdns data structure, otherwise the
kernel will report the following warning:
BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1163
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 651, name: sh
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
CPU: 0 PID: 651 Comm: sh Tainted: G WC 6.1.20 #1
Hardware name: Freescale i.MX8QM MEK (DT)
Call trace:
dump_backtrace.part.0+0xe0/0xf0
show_stack+0x18/0x30
dump_stack_lvl+0x64/0x80
dump_stack+0x1c/0x38
__might_resched+0x1fc/0x240
__might_sleep+0x68/0xc0
__pm_runtime_resume+0x9c/0xe0
rpm_get_suppliers+0x68/0x1b0
__pm_runtime_set_status+0x298/0x560
cdns_resume+0xb0/0x1c0
cdns3_controller_resume.isra.0+0x1e0/0x250
cdns3_plat_resume+0x28/0x40
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
drm/client: Fix memory leak in drm_client_modeset_probe
When a new mode is set to modeset->mode, the previous mode should be freed.
This fixes the following kmemleak report:
drm_mode_duplicate+0x45/0x220 [drm]
drm_client_modeset_probe+0x944/0xf50 [drm]
__drm_fb_helper_initial_config_and_unlock+0xb4/0x2c0 [drm_kms_helper]
drm_fbdev_client_hotplug+0x2bc/0x4d0 [drm_kms_helper]
drm_client_register+0x169/0x240 [drm]
ast_pci_probe+0x142/0x190 [ast]
local_pci_probe+0xdc/0x180
work_for_cpu_fn+0x4e/0xa0
process_one_work+0x8b7/0x1540
worker_thread+0x70a/0xed0
kthread+0x29f/0x340
ret_from_fork+0x1f/0x30
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-16
In the Linux kernel, the following vulnerability has been resolved:
net: ena: fix shift-out-of-bounds in exponential backoff
The ENA adapters on our instances occasionally reset. Once recently
logged a UBSAN failure to console in the process:
UBSAN: shift-out-of-bounds in build/linux/drivers/net/ethernet/amazon/ena/ena_com.c:540:13
shift exponent 32 is too large for 32-bit type 'unsigned int'
CPU: 28 PID: 70012 Comm: kworker/u72:2 Kdump: loaded not tainted 5.15.117
Hardware name: Amazon EC2 c5d.9xlarge/, BIOS 1.0 10/16/2017
Workqueue: ena ena_fw_reset_device [ena]
Call Trace:
<TASK>
dump_stack_lvl+0x4a/0x63
dump_stack+0x10/0x16
ubsan_epilogue+0x9/0x36
__ubsan_handle_shift_out_of_bounds.cold+0x61/0x10e
? __const_udelay+0x43/0x50
ena_delay_exponential_backoff_us.cold+0x16/0x1e [ena]
wait_for_reset_state+0x54/0xa0 [ena]
ena_com_dev_reset+0xc8/0x110 [ena]
ena_down+0x3fe/0x480 [ena]
ena_destroy_device+0xeb/0xf0 [ena]
ena_fw_reset_device+0x30/0x50 [ena]
process_one_work+0x22b/0x3d0
worker_thread+0x4d/0x3f0
? process_one_work+0x3d0/0x3d0
kthread+0x12a/0x150
? set_kthread_struct+0x50/0x50
ret_from_fork+0x22/0x30
</TASK>
Apparently, the reset delays are getting so large they can trigger a
UBSAN panic.
Looking at the code, the current timeout is capped at 5000us. Using a
base value of 100us, the current code will overflow after (1<<29). Even
at values before 32, this function wraps around, perhaps
unintentionally.
Cap the value of the exponent used for this backoff at (1<<16) which is
larger than currently necessary, but large enough to support bigger
values in the future.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-16