Linux: >> Linux Kernel >> 4.9.101 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
fs: dlm: fix invalid derefence of sb_lvbptr
I experience issues when putting a lkbsb on the stack and have sb_lvbptr
field to a dangled pointer while not using DLM_LKF_VALBLK. It will crash
with the following kernel message, the dangled pointer is here
0xdeadbeef as example:
[ 102.749317] BUG: unable to handle page fault for address: 00000000deadbeef
[ 102.749320] #PF: supervisor read access in kernel mode
[ 102.749323] #PF: error_code(0x0000) - not-present page
[ 102.749325] PGD 0 P4D 0
[ 102.749332] Oops: 0000 [#1] PREEMPT SMP PTI
[ 102.749336] CPU: 0 PID: 1567 Comm: lock_torture_wr Tainted: G W 5.19.0-rc3+ #1565
[ 102.749343] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-2.module+el8.7.0+15506+033991b0 04/01/2014
[ 102.749344] RIP: 0010:memcpy_erms+0x6/0x10
[ 102.749353] Code: cc cc cc cc eb 1e 0f 1f 00 48 89 f8 48 89 d1 48 c1 e9 03 83 e2 07 f3 48 a5 89 d1 f3 a4 c3 66 0f 1f 44 00 00 48 89 f8 48 89 d1 <f3> a4 c3 0f 1f 80 00 00 00 00 48 89 f8 48 83 fa 20 72 7e 40 38 fe
[ 102.749355] RSP: 0018:ffff97a58145fd08 EFLAGS: 00010202
[ 102.749358] RAX: ffff901778b77070 RBX: 0000000000000000 RCX: 0000000000000040
[ 102.749360] RDX: 0000000000000040 RSI: 00000000deadbeef RDI: ffff901778b77070
[ 102.749362] RBP: ffff97a58145fd10 R08: ffff901760b67a70 R09: 0000000000000001
[ 102.749364] R10: ffff9017008e2cb8 R11: 0000000000000001 R12: ffff901760b67a70
[ 102.749366] R13: ffff901760b78f00 R14: 0000000000000003 R15: 0000000000000001
[ 102.749368] FS: 0000000000000000(0000) GS:ffff901876e00000(0000) knlGS:0000000000000000
[ 102.749372] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 102.749374] CR2: 00000000deadbeef CR3: 000000017c49a004 CR4: 0000000000770ef0
[ 102.749376] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 102.749378] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 102.749379] PKRU: 55555554
[ 102.749381] Call Trace:
[ 102.749382] <TASK>
[ 102.749383] ? send_args+0xb2/0xd0
[ 102.749389] send_common+0xb7/0xd0
[ 102.749395] _unlock_lock+0x2c/0x90
[ 102.749400] unlock_lock.isra.56+0x62/0xa0
[ 102.749405] dlm_unlock+0x21e/0x330
[ 102.749411] ? lock_torture_stats+0x80/0x80 [dlm_locktorture]
[ 102.749416] torture_unlock+0x5a/0x90 [dlm_locktorture]
[ 102.749419] ? preempt_count_sub+0xba/0x100
[ 102.749427] lock_torture_writer+0xbd/0x150 [dlm_locktorture]
[ 102.786186] kthread+0x10a/0x130
[ 102.786581] ? kthread_complete_and_exit+0x20/0x20
[ 102.787156] ret_from_fork+0x22/0x30
[ 102.787588] </TASK>
[ 102.787855] Modules linked in: dlm_locktorture torture rpcsec_gss_krb5 intel_rapl_msr intel_rapl_common kvm_intel iTCO_wdt iTCO_vendor_support kvm vmw_vsock_virtio_transport qxl irqbypass vmw_vsock_virtio_transport_common drm_ttm_helper crc32_pclmul joydev crc32c_intel ttm vsock virtio_scsi virtio_balloon snd_pcm drm_kms_helper virtio_console snd_timer snd drm soundcore syscopyarea i2c_i801 sysfillrect sysimgblt i2c_smbus pcspkr fb_sys_fops lpc_ich serio_raw
[ 102.792536] CR2: 00000000deadbeef
[ 102.792930] ---[ end trace 0000000000000000 ]---
This patch fixes the issue by checking also on DLM_LKF_VALBLK on exflags
is set when copying the lvbptr array instead of if it's just null which
fixes for me the issue.
I think this patch can fix other dlm users as well, depending how they
handle the init, freeing memory handling of sb_lvbptr and don't set
DLM_LKF_VALBLK for some dlm_lock() calls. It might a there could be a
hidden issue all the time. However with checking on DLM_LKF_VALBLK the
user always need to provide a sb_lvbptr non-null value. There might be
more intelligent handling between per ls lvblen, DLM_LKF_VALBLK and
non-null to report the user the way how DLM API is used is wrong but can
be added for later, this will only fix the current behaviour.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
parisc: Fix locking in pdc_iodc_print() firmware call
Utilize pdc_lock spinlock to protect parallel modifications of the
iodc_dbuf[] buffer, check length to prevent buffer overflow of
iodc_dbuf[], drop the iodc_retbuf[] buffer and fix some wrong
indentings.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: replace WARN_ONs by nilfs_error for checkpoint acquisition failure
If creation or finalization of a checkpoint fails due to anomalies in the
checkpoint metadata on disk, a kernel warning is generated.
This patch replaces the WARN_ONs by nilfs_error, so that a kernel, booted
with panic_on_warn, does not panic. A nilfs_error is appropriate here to
handle the abnormal filesystem condition.
This also replaces the detected error codes with an I/O error so that
neither of the internal error codes is returned to callers.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: Fix PCI device refcount leak in radeon_atrm_get_bios()
As comment of pci_get_class() says, it returns a pci_device with its
refcount increased and decreased the refcount for the input parameter
@from if it is not NULL.
If we break the loop in radeon_atrm_get_bios() with 'pdev' not NULL, we
need to call pci_dev_put() to decrease the refcount. Add the missing
pci_dev_put() to avoid refcount leak.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
platform/x86: mxm-wmi: fix memleak in mxm_wmi_call_mx[ds|mx]()
The ACPI buffer memory (out.pointer) returned by wmi_evaluate_method()
is not freed after the call, so it leads to memory leak.
The method results in ACPI buffer is not used, so just pass NULL to
wmi_evaluate_method() which fixes the memory leak.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
lib/fonts: fix undefined behavior in bit shift for get_default_font
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 lib/fonts/fonts.c:139:20
left shift of 1 by 31 places cannot be represented in type 'int'
<TASK>
dump_stack_lvl+0x7d/0xa5
dump_stack+0x15/0x1b
ubsan_epilogue+0xe/0x4e
__ubsan_handle_shift_out_of_bounds+0x1e7/0x20c
get_default_font+0x1c7/0x1f0
fbcon_startup+0x347/0x3a0
do_take_over_console+0xce/0x270
do_fbcon_takeover+0xa1/0x170
do_fb_registered+0x2a8/0x340
fbcon_fb_registered+0x47/0xe0
register_framebuffer+0x294/0x4a0
__drm_fb_helper_initial_config_and_unlock+0x43c/0x880 [drm_kms_helper]
drm_fb_helper_initial_config+0x52/0x80 [drm_kms_helper]
drm_fbdev_client_hotplug+0x156/0x1b0 [drm_kms_helper]
drm_fbdev_generic_setup+0xfc/0x290 [drm_kms_helper]
bochs_pci_probe+0x6ca/0x772 [bochs]
local_pci_probe+0x4d/0xb0
pci_device_probe+0x119/0x320
really_probe+0x181/0x550
__driver_probe_device+0xc6/0x220
driver_probe_device+0x32/0x100
__driver_attach+0x195/0x200
bus_for_each_dev+0xbb/0x120
driver_attach+0x27/0x30
bus_add_driver+0x22e/0x2f0
driver_register+0xa9/0x190
__pci_register_driver+0x90/0xa0
bochs_pci_driver_init+0x52/0x1000 [bochs]
do_one_initcall+0x76/0x430
do_init_module+0x61/0x28a
load_module+0x1f82/0x2e50
__do_sys_finit_module+0xf8/0x190
__x64_sys_finit_module+0x23/0x30
do_syscall_64+0x58/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
</TASK>
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: f_hid: fix refcount leak on error path
When failing to allocate report_desc, opts->refcnt has already been
incremented so it needs to be decremented to avoid leaving the options
structure permanently locked.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
media: coda: Add check for kmalloc
As the kmalloc may return NULL pointer,
it should be better to check the return value
in order to avoid NULL poineter dereference,
same as the others.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix invalid free of JFS_IP(ipimap)->i_imap in diUnmount
syzbot found an invalid-free in diUnmount:
BUG: KASAN: double-free in slab_free mm/slub.c:3661 [inline]
BUG: KASAN: double-free in __kmem_cache_free+0x71/0x110 mm/slub.c:3674
Free of addr ffff88806f410000 by task syz-executor131/3632
CPU: 0 PID: 3632 Comm: syz-executor131 Not tainted 6.1.0-rc7-syzkaller-00012-gca57f02295f1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106
print_address_description+0x74/0x340 mm/kasan/report.c:284
print_report+0x107/0x1f0 mm/kasan/report.c:395
kasan_report_invalid_free+0xac/0xd0 mm/kasan/report.c:460
____kasan_slab_free+0xfb/0x120
kasan_slab_free include/linux/kasan.h:177 [inline]
slab_free_hook mm/slub.c:1724 [inline]
slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1750
slab_free mm/slub.c:3661 [inline]
__kmem_cache_free+0x71/0x110 mm/slub.c:3674
diUnmount+0xef/0x100 fs/jfs/jfs_imap.c:195
jfs_umount+0x108/0x370 fs/jfs/jfs_umount.c:63
jfs_put_super+0x86/0x190 fs/jfs/super.c:194
generic_shutdown_super+0x130/0x310 fs/super.c:492
kill_block_super+0x79/0xd0 fs/super.c:1428
deactivate_locked_super+0xa7/0xf0 fs/super.c:332
cleanup_mnt+0x494/0x520 fs/namespace.c:1186
task_work_run+0x243/0x300 kernel/task_work.c:179
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0x664/0x2070 kernel/exit.c:820
do_group_exit+0x1fd/0x2b0 kernel/exit.c:950
__do_sys_exit_group kernel/exit.c:961 [inline]
__se_sys_exit_group kernel/exit.c:959 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:959
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
[...]
JFS_IP(ipimap)->i_imap is not setting to NULL after free in diUnmount.
If jfs_remount() free JFS_IP(ipimap)->i_imap but then failed at diMount().
JFS_IP(ipimap)->i_imap will be freed once again.
Fix this problem by setting JFS_IP(ipimap)->i_imap to NULL after free.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
nilfs2: fix potential UAF of struct nilfs_sc_info in nilfs_segctor_thread()
The finalization of nilfs_segctor_thread() can race with
nilfs_segctor_kill_thread() which terminates that thread, potentially
causing a use-after-free BUG as KASAN detected.
At the end of nilfs_segctor_thread(), it assigns NULL to "sc_task" member
of "struct nilfs_sc_info" to indicate the thread has finished, and then
notifies nilfs_segctor_kill_thread() of this using waitqueue
"sc_wait_task" on the struct nilfs_sc_info.
However, here, immediately after the NULL assignment to "sc_task", it is
possible that nilfs_segctor_kill_thread() will detect it and return to
continue the deallocation, freeing the nilfs_sc_info structure before the
thread does the notification.
This fixes the issue by protecting the NULL assignment to "sc_task" and
its notification, with spinlock "sc_state_lock" of the struct
nilfs_sc_info. Since nilfs_segctor_kill_thread() does a final check to
see if "sc_task" is NULL with "sc_state_lock" locked, this can eliminate
the race.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-04