Linux: >> Linux Kernel >> 6.1.26 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
btrfs: reject invalid reloc tree root keys with stack dump
[BUG]
Syzbot reported a crash that an ASSERT() got triggered inside
prepare_to_merge().
That ASSERT() makes sure the reloc tree is properly pointed back by its
subvolume tree.
[CAUSE]
After more debugging output, it turns out we had an invalid reloc tree:
BTRFS error (device loop1): reloc tree mismatch, root 8 has no reloc root, expect reloc root key (-8, 132, 8) gen 17
Note the above root key is (TREE_RELOC_OBJECTID, ROOT_ITEM,
QUOTA_TREE_OBJECTID), meaning it's a reloc tree for quota tree.
But reloc trees can only exist for subvolumes, as for non-subvolume
trees, we just COW the involved tree block, no need to create a reloc
tree since those tree blocks won't be shared with other trees.
Only subvolumes tree can share tree blocks with other trees (thus they
have BTRFS_ROOT_SHAREABLE flag).
Thus this new debug output proves my previous assumption that corrupted
on-disk data can trigger that ASSERT().
[FIX]
Besides the dedicated fix and the graceful exit, also let tree-checker to
check such root keys, to make sure reloc trees can only exist for subvolumes.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
netfilter: conntrack: Avoid nf_ct_helper_hash uses after free
If nf_conntrack_init_start() fails (for example due to a
register_nf_conntrack_bpf() failure), the nf_conntrack_helper_fini()
clean-up path frees the nf_ct_helper_hash map.
When built with NF_CONNTRACK=y, further netfilter modules (e.g:
netfilter_conntrack_ftp) can still be loaded and call
nf_conntrack_helpers_register(), independently of whether nf_conntrack
initialized correctly. This accesses the nf_ct_helper_hash dangling
pointer and causes a uaf, possibly leading to random memory corruption.
This patch guards nf_conntrack_helper_register() from accessing a freed
or uninitialized nf_ct_helper_hash pointer and fixes possible
uses-after-free when loading a conntrack module.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
md: fix soft lockup in status_resync
status_resync() will calculate 'curr_resync - recovery_active' to show
user a progress bar like following:
[============>........] resync = 61.4%
'curr_resync' and 'recovery_active' is updated in md_do_sync(), and
status_resync() can read them concurrently, hence it's possible that
'curr_resync - recovery_active' can overflow to a huge number. In this
case status_resync() will be stuck in the loop to print a large amount
of '=', which will end up soft lockup.
Fix the problem by setting 'resync' to MD_RESYNC_ACTIVE in this case,
this way resync in progress will be reported to user.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
gfs2: Fix possible data races in gfs2_show_options()
Some fields such as gt_logd_secs of the struct gfs2_tune are accessed
without holding the lock gt_spin in gfs2_show_options():
val = sdp->sd_tune.gt_logd_secs;
if (val != 30)
seq_printf(s, ",commit=%d", val);
And thus can cause data races when gfs2_show_options() and other functions
such as gfs2_reconfigure() are concurrently executed:
spin_lock(>->gt_spin);
gt->gt_logd_secs = newargs->ar_commit;
To fix these possible data races, the lock sdp->sd_tune.gt_spin is
acquired before accessing the fields of gfs2_tune and released after these
accesses.
Further changes by Andreas:
- Don't hold the spin lock over the seq_printf operations.
CVSS Score
7.0
EPSS Score
0.0
Published
2025-10-07
In the Linux kernel, the following vulnerability has been resolved:
dax: Fix dax_mapping_release() use after free
A CONFIG_DEBUG_KOBJECT_RELEASE test of removing a device-dax region
provider (like modprobe -r dax_hmem) yields:
kobject: 'mapping0' (ffff93eb460e8800): kobject_release, parent 0000000000000000 (delayed 2000)
[..]
DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 23 PID: 282 at kernel/locking/lockdep.c:232 __lock_acquire+0x9fc/0x2260
[..]
RIP: 0010:__lock_acquire+0x9fc/0x2260
[..]
Call Trace:
<TASK>
[..]
lock_acquire+0xd4/0x2c0
? ida_free+0x62/0x130
_raw_spin_lock_irqsave+0x47/0x70
? ida_free+0x62/0x130
ida_free+0x62/0x130
dax_mapping_release+0x1f/0x30
device_release+0x36/0x90
kobject_delayed_cleanup+0x46/0x150
Due to attempting ida_free() on an ida object that has already been
freed. Devices typically only hold a reference on their parent while
registered. If a child needs a parent object to complete its release it
needs to hold a reference that it drops from its release callback.
Arrange for a dax_mapping to pin its parent dev_dax instance until
dax_mapping_release().
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix deletion race condition
System crash when using debug kernel due to link list corruption. The cause
of the link list corruption is due to session deletion was allowed to queue
up twice. Here's the internal trace that show the same port was allowed to
double queue for deletion on different cpu.
20808683956 015 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
20808683957 027 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
Move the clearing/setting of deleted flag lock.
CVSS Score
4.7
EPSS Score
0.0
Published
2025-10-04
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:
dm integrity: call kmem_cache_destroy() in dm_integrity_init() error path
Otherwise the journal_io_cache will leak if dm_register_target() fails.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
ipmi_si: fix a memleak in try_smi_init()
Kmemleak reported the following leak info in try_smi_init():
unreferenced object 0xffff00018ecf9400 (size 1024):
comm "modprobe", pid 2707763, jiffies 4300851415 (age 773.308s)
backtrace:
[<000000004ca5b312>] __kmalloc+0x4b8/0x7b0
[<00000000953b1072>] try_smi_init+0x148/0x5dc [ipmi_si]
[<000000006460d325>] 0xffff800081b10148
[<0000000039206ea5>] do_one_initcall+0x64/0x2a4
[<00000000601399ce>] do_init_module+0x50/0x300
[<000000003c12ba3c>] load_module+0x7a8/0x9e0
[<00000000c246fffe>] __se_sys_init_module+0x104/0x180
[<00000000eea99093>] __arm64_sys_init_module+0x24/0x30
[<0000000021b1ef87>] el0_svc_common.constprop.0+0x94/0x250
[<0000000070f4f8b7>] do_el0_svc+0x48/0xe0
[<000000005a05337f>] el0_svc+0x24/0x3c
[<000000005eb248d6>] el0_sync_handler+0x160/0x164
[<0000000030a59039>] el0_sync+0x160/0x180
The problem was that when an error occurred before handlers registration
and after allocating `new_smi->si_sm`, the variable wouldn't be freed in
the error handling afterwards since `shutdown_smi()` hadn't been
registered yet. Fix it by adding a `kfree()` in the error handling path
in `try_smi_init()`.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04
In the Linux kernel, the following vulnerability has been resolved:
octeontx2-pf: mcs: Fix NULL pointer dereferences
When system is rebooted after creating macsec interface
below NULL pointer dereference crashes occurred. This
patch fixes those crashes by using correct order of teardown
[ 3324.406942] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[ 3324.415726] Mem abort info:
[ 3324.418510] ESR = 0x96000006
[ 3324.421557] EC = 0x25: DABT (current EL), IL = 32 bits
[ 3324.426865] SET = 0, FnV = 0
[ 3324.429913] EA = 0, S1PTW = 0
[ 3324.433047] Data abort info:
[ 3324.435921] ISV = 0, ISS = 0x00000006
[ 3324.439748] CM = 0, WnR = 0
....
[ 3324.575915] Call trace:
[ 3324.578353] cn10k_mdo_del_secy+0x24/0x180
[ 3324.582440] macsec_common_dellink+0xec/0x120
[ 3324.586788] macsec_notify+0x17c/0x1c0
[ 3324.590529] raw_notifier_call_chain+0x50/0x70
[ 3324.594965] call_netdevice_notifiers_info+0x34/0x7c
[ 3324.599921] rollback_registered_many+0x354/0x5bc
[ 3324.604616] unregister_netdevice_queue+0x88/0x10c
[ 3324.609399] unregister_netdev+0x20/0x30
[ 3324.613313] otx2_remove+0x8c/0x310
[ 3324.616794] pci_device_shutdown+0x30/0x70
[ 3324.620882] device_shutdown+0x11c/0x204
[ 966.664930] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[ 966.673712] Mem abort info:
[ 966.676497] ESR = 0x96000006
[ 966.679543] EC = 0x25: DABT (current EL), IL = 32 bits
[ 966.684848] SET = 0, FnV = 0
[ 966.687895] EA = 0, S1PTW = 0
[ 966.691028] Data abort info:
[ 966.693900] ISV = 0, ISS = 0x00000006
[ 966.697729] CM = 0, WnR = 0
[ 966.833467] Call trace:
[ 966.835904] cn10k_mdo_stop+0x20/0xa0
[ 966.839557] macsec_dev_stop+0xe8/0x11c
[ 966.843384] __dev_close_many+0xbc/0x140
[ 966.847298] dev_close_many+0x84/0x120
[ 966.851039] rollback_registered_many+0x114/0x5bc
[ 966.855735] unregister_netdevice_many.part.0+0x14/0xa0
[ 966.860952] unregister_netdevice_many+0x18/0x24
[ 966.865560] macsec_notify+0x1ac/0x1c0
[ 966.869303] raw_notifier_call_chain+0x50/0x70
[ 966.873738] call_netdevice_notifiers_info+0x34/0x7c
[ 966.878694] rollback_registered_many+0x354/0x5bc
[ 966.883390] unregister_netdevice_queue+0x88/0x10c
[ 966.888173] unregister_netdev+0x20/0x30
[ 966.892090] otx2_remove+0x8c/0x310
[ 966.895571] pci_device_shutdown+0x30/0x70
[ 966.899660] device_shutdown+0x11c/0x204
[ 966.903574] __do_sys_reboot+0x208/0x290
[ 966.907487] __arm64_sys_reboot+0x20/0x30
[ 966.911489] el0_svc_handler+0x80/0x1c0
[ 966.915316] el0_svc+0x8/0x180
[ 966.918362] Code: f9400000 f9400a64 91220014 f94b3403 (f9400060)
[ 966.924448] ---[ end trace 341778e799c3d8d7 ]---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-10-04