Security Vulnerabilities - CVEs Published In September 2025
In the Linux kernel, the following vulnerability has been resolved:
mm/memory-failure: fix VM_BUG_ON_PAGE(PagePoisoned(page)) when unpoison memory
When I did memory failure tests, below panic occurs:
page dumped because: VM_BUG_ON_PAGE(PagePoisoned(page))
kernel BUG at include/linux/page-flags.h:616!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 3 PID: 720 Comm: bash Not tainted 6.10.0-rc1-00195-g148743902568 #40
RIP: 0010:unpoison_memory+0x2f3/0x590
RSP: 0018:ffffa57fc8787d60 EFLAGS: 00000246
RAX: 0000000000000037 RBX: 0000000000000009 RCX: ffff9be25fcdc9c8
RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff9be25fcdc9c0
RBP: 0000000000300000 R08: ffffffffb4956f88 R09: 0000000000009ffb
R10: 0000000000000284 R11: ffffffffb4926fa0 R12: ffffe6b00c000000
R13: ffff9bdb453dfd00 R14: 0000000000000000 R15: fffffffffffffffe
FS: 00007f08f04e4740(0000) GS:ffff9be25fcc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564787a30410 CR3: 000000010d4e2000 CR4: 00000000000006f0
Call Trace:
<TASK>
unpoison_memory+0x2f3/0x590
simple_attr_write_xsigned.constprop.0.isra.0+0xb3/0x110
debugfs_attr_write+0x42/0x60
full_proxy_write+0x5b/0x80
vfs_write+0xd5/0x540
ksys_write+0x64/0xe0
do_syscall_64+0xb9/0x1d0
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f08f0314887
RSP: 002b:00007ffece710078 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000009 RCX: 00007f08f0314887
RDX: 0000000000000009 RSI: 0000564787a30410 RDI: 0000000000000001
RBP: 0000564787a30410 R08: 000000000000fefe R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007f08f041b780 R14: 00007f08f0417600 R15: 00007f08f0416a00
</TASK>
Modules linked in: hwpoison_inject
---[ end trace 0000000000000000 ]---
RIP: 0010:unpoison_memory+0x2f3/0x590
RSP: 0018:ffffa57fc8787d60 EFLAGS: 00000246
RAX: 0000000000000037 RBX: 0000000000000009 RCX: ffff9be25fcdc9c8
RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff9be25fcdc9c0
RBP: 0000000000300000 R08: ffffffffb4956f88 R09: 0000000000009ffb
R10: 0000000000000284 R11: ffffffffb4926fa0 R12: ffffe6b00c000000
R13: ffff9bdb453dfd00 R14: 0000000000000000 R15: fffffffffffffffe
FS: 00007f08f04e4740(0000) GS:ffff9be25fcc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000564787a30410 CR3: 000000010d4e2000 CR4: 00000000000006f0
Kernel panic - not syncing: Fatal exception
Kernel Offset: 0x31c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
---[ end Kernel panic - not syncing: Fatal exception ]---
The root cause is that unpoison_memory() tries to check the PG_HWPoison
flags of an uninitialized page. So VM_BUG_ON_PAGE(PagePoisoned(page)) is
triggered. This can be reproduced by below steps:
1.Offline memory block:
echo offline > /sys/devices/system/memory/memory12/state
2.Get offlined memory pfn:
page-types -b n -rlN
3.Write pfn to unpoison-pfn
echo <pfn> > /sys/kernel/debug/hwpoison/unpoison-pfn
This scenario can be identified by pfn_to_online_page() returning NULL.
And ZONE_DEVICE pages are never expected, so we can simply fail if
pfn_to_online_page() == NULL to fix the bug.
CVSS Score
7.1
EPSS Score
0.002
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix subvolume deletion lockup caused by inodes xarray race
There is a race condition between inode eviction and inode caching that
can cause a live struct btrfs_inode to be missing from the root->inodes
xarray. Specifically, there is a window during evict() between the inode
being unhashed and deleted from the xarray. If btrfs_iget() is called
for the same inode in that window, it will be recreated and inserted
into the xarray, but then eviction will delete the new entry, leaving
nothing in the xarray:
Thread 1 Thread 2
---------------------------------------------------------------
evict()
remove_inode_hash()
btrfs_iget_path()
btrfs_iget_locked()
btrfs_read_locked_inode()
btrfs_add_inode_to_root()
destroy_inode()
btrfs_destroy_inode()
btrfs_del_inode_from_root()
__xa_erase
In turn, this can cause issues for subvolume deletion. Specifically, if
an inode is in this lost state, and all other inodes are evicted, then
btrfs_del_inode_from_root() will call btrfs_add_dead_root() prematurely.
If the lost inode has a delayed_node attached to it, then when
btrfs_clean_one_deleted_snapshot() calls btrfs_kill_all_delayed_nodes(),
it will loop forever because the delayed_nodes xarray will never become
empty (unless memory pressure forces the inode out). We saw this
manifest as soft lockups in production.
Fix it by only deleting the xarray entry if it matches the given inode
(using __xa_cmpxchg()).
CVSS Score
4.7
EPSS Score
0.001
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: fix recursive semaphore deadlock in fiemap call
syzbot detected a OCFS2 hang due to a recursive semaphore on a
FS_IOC_FIEMAP of the extent list on a specially crafted mmap file.
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7115
rwsem_down_write_slowpath+0x872/0xfe0 kernel/locking/rwsem.c:1185
__down_write_common kernel/locking/rwsem.c:1317 [inline]
__down_write kernel/locking/rwsem.c:1326 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1591
ocfs2_page_mkwrite+0x2ff/0xc40 fs/ocfs2/mmap.c:142
do_page_mkwrite+0x14d/0x310 mm/memory.c:3361
wp_page_shared mm/memory.c:3762 [inline]
do_wp_page+0x268d/0x5800 mm/memory.c:3981
handle_pte_fault mm/memory.c:6068 [inline]
__handle_mm_fault+0x1033/0x5440 mm/memory.c:6195
handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364
do_user_addr_fault+0x764/0x1390 arch/x86/mm/fault.c:1387
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0010:copy_user_generic arch/x86/include/asm/uaccess_64.h:126 [inline]
RIP: 0010:raw_copy_to_user arch/x86/include/asm/uaccess_64.h:147 [inline]
RIP: 0010:_inline_copy_to_user include/linux/uaccess.h:197 [inline]
RIP: 0010:_copy_to_user+0x85/0xb0 lib/usercopy.c:26
Code: e8 00 bc f7 fc 4d 39 fc 72 3d 4d 39 ec 77 38 e8 91 b9 f7 fc 4c 89
f7 89 de e8 47 25 5b fd 0f 01 cb 4c 89 ff 48 89 d9 4c 89 f6 <f3> a4 0f
1f 00 48 89 cb 0f 01 ca 48 89 d8 5b 41 5c 41 5d 41 5e 41
RSP: 0018:ffffc9000403f950 EFLAGS: 00050256
RAX: ffffffff84c7f101 RBX: 0000000000000038 RCX: 0000000000000038
RDX: 0000000000000000 RSI: ffffc9000403f9e0 RDI: 0000200000000060
RBP: ffffc9000403fa90 R08: ffffc9000403fa17 R09: 1ffff92000807f42
R10: dffffc0000000000 R11: fffff52000807f43 R12: 0000200000000098
R13: 00007ffffffff000 R14: ffffc9000403f9e0 R15: 0000200000000060
copy_to_user include/linux/uaccess.h:225 [inline]
fiemap_fill_next_extent+0x1c0/0x390 fs/ioctl.c:145
ocfs2_fiemap+0x888/0xc90 fs/ocfs2/extent_map.c:806
ioctl_fiemap fs/ioctl.c:220 [inline]
do_vfs_ioctl+0x1173/0x1430 fs/ioctl.c:532
__do_sys_ioctl fs/ioctl.c:596 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:584
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f13850fd9
RSP: 002b:00007ffe3b3518b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000200000000000 RCX: 00007f5f13850fd9
RDX: 0000200000000040 RSI: 00000000c020660b RDI: 0000000000000004
RBP: 6165627472616568 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3b3518f0
R13: 00007ffe3b351b18 R14: 431bde82d7b634db R15: 00007f5f1389a03b
ocfs2_fiemap() takes a read lock of the ip_alloc_sem semaphore (since
v2.6.22-527-g7307de80510a) and calls fiemap_fill_next_extent() to read the
extent list of this running mmap executable. The user supplied buffer to
hold the fiemap information page faults calling ocfs2_page_mkwrite() which
will take a write lock (since v2.6.27-38-g00dc417fa3e7) of the same
semaphore. This recursive semaphore will hold filesystem locks and causes
a hang of the fileystem.
The ip_alloc_sem protects the inode extent list and size. Release the
read semphore before calling fiemap_fill_next_extent() in ocfs2_fiemap()
and ocfs2_fiemap_inline(). This does an unnecessary semaphore lock/unlock
on the last extent but simplifies the error path.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
bpf: Tell memcg to use allow_spinning=false path in bpf_timer_init()
Currently, calling bpf_map_kmalloc_node() from __bpf_async_init() can
cause various locking issues; see the following stack trace (edited for
style) as one example:
...
[10.011566] do_raw_spin_lock.cold
[10.011570] try_to_wake_up (5) double-acquiring the same
[10.011575] kick_pool rq_lock, causing a hardlockup
[10.011579] __queue_work
[10.011582] queue_work_on
[10.011585] kernfs_notify
[10.011589] cgroup_file_notify
[10.011593] try_charge_memcg (4) memcg accounting raises an
[10.011597] obj_cgroup_charge_pages MEMCG_MAX event
[10.011599] obj_cgroup_charge_account
[10.011600] __memcg_slab_post_alloc_hook
[10.011603] __kmalloc_node_noprof
...
[10.011611] bpf_map_kmalloc_node
[10.011612] __bpf_async_init
[10.011615] bpf_timer_init (3) BPF calls bpf_timer_init()
[10.011617] bpf_prog_xxxxxxxxxxxxxxxx_fcg_runnable
[10.011619] bpf__sched_ext_ops_runnable
[10.011620] enqueue_task_scx (2) BPF runs with rq_lock held
[10.011622] enqueue_task
[10.011626] ttwu_do_activate
[10.011629] sched_ttwu_pending (1) grabs rq_lock
...
The above was reproduced on bpf-next (b338cf849ec8) by modifying
./tools/sched_ext/scx_flatcg.bpf.c to call bpf_timer_init() during
ops.runnable(), and hacking the memcg accounting code a bit to make
a bpf_timer_init() call more likely to raise an MEMCG_MAX event.
We have also run into other similar variants (both internally and on
bpf-next), including double-acquiring cgroup_file_kn_lock, the same
worker_pool::lock, etc.
As suggested by Shakeel, fix this by using __GFP_HIGH instead of
GFP_ATOMIC in __bpf_async_init(), so that e.g. if try_charge_memcg()
raises an MEMCG_MAX event, we call __memcg_memory_event() with
@allow_spinning=false and avoid calling cgroup_file_notify() there.
Depends on mm patch
"memcg: skip cgroup_file_notify if spinning is not allowed":
https://lore.kernel.org/bpf/20250905201606.66198-1-shakeel.butt@linux.dev/
v0 approach s/bpf_map_kmalloc_node/bpf_mem_alloc/
https://lore.kernel.org/bpf/20250905061919.439648-1-yepeilin@google.com/
v1 approach:
https://lore.kernel.org/bpf/20250905234547.862249-1-yepeilin@google.com/
CVSS Score
5.5
EPSS Score
0.001
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
tracing/osnoise: Fix null-ptr-deref in bitmap_parselist()
A crash was observed with the following output:
BUG: kernel NULL pointer dereference, address: 0000000000000010
Oops: Oops: 0000 [#1] SMP NOPTI
CPU: 2 UID: 0 PID: 92 Comm: osnoise_cpus Not tainted 6.17.0-rc4-00201-gd69eb204c255 #138 PREEMPT(voluntary)
RIP: 0010:bitmap_parselist+0x53/0x3e0
Call Trace:
<TASK>
osnoise_cpus_write+0x7a/0x190
vfs_write+0xf8/0x410
? do_sys_openat2+0x88/0xd0
ksys_write+0x60/0xd0
do_syscall_64+0xa4/0x260
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
This issue can be reproduced by below code:
fd=open("/sys/kernel/debug/tracing/osnoise/cpus", O_WRONLY);
write(fd, "0-2", 0);
When user pass 'count=0' to osnoise_cpus_write(), kmalloc() will return
ZERO_SIZE_PTR (16) and cpulist_parse() treat it as a normal value, which
trigger the null pointer dereference. Add check for the parameter 'count'.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
fuse: Block access to folio overlimit
syz reported a slab-out-of-bounds Write in fuse_dev_do_write.
When the number of bytes to be retrieved is truncated to the upper limit
by fc->max_pages and there is an offset, the oob is triggered.
Add a loop termination condition to prevent overruns.
CVSS Score
7.8
EPSS Score
0.001
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
net: fec: Fix possible NPD in fec_enet_phy_reset_after_clk_enable()
The function of_phy_find_device may return NULL, so we need to take
care before dereferencing phy_dev.
CVSS Score
5.5
EPSS Score
0.002
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
mm/damon/sysfs: fix use-after-free in state_show()
state_show() reads kdamond->damon_ctx without holding damon_sysfs_lock.
This allows a use-after-free race:
CPU 0 CPU 1
----- -----
state_show() damon_sysfs_turn_damon_on()
ctx = kdamond->damon_ctx; mutex_lock(&damon_sysfs_lock);
damon_destroy_ctx(kdamond->damon_ctx);
kdamond->damon_ctx = NULL;
mutex_unlock(&damon_sysfs_lock);
damon_is_running(ctx); /* ctx is freed */
mutex_lock(&ctx->kdamond_lock); /* UAF */
(The race can also occur with damon_sysfs_kdamonds_rm_dirs() and
damon_sysfs_kdamond_release(), which free or replace the context under
damon_sysfs_lock.)
Fix by taking damon_sysfs_lock before dereferencing the context, mirroring
the locking used in pid_show().
The bug has existed since state_show() first accessed kdamond->damon_ctx.
CVSS Score
7.8
EPSS Score
0.002
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix crash after fscrypt_encrypt_pagecache_blocks() error
The function move_dirty_folio_in_page_array() was created by commit
ce80b76dd327 ("ceph: introduce ceph_process_folio_batch() method") by
moving code from ceph_writepages_start() to this function.
This new function is supposed to return an error code which is checked
by the caller (now ceph_process_folio_batch()), and on error, the
caller invokes redirty_page_for_writepage() and then breaks from the
loop.
However, the refactoring commit has gone wrong, and it by accident, it
always returns 0 (= success) because it first NULLs the pointer and
then returns PTR_ERR(NULL) which is always 0. This means errors are
silently ignored, leaving NULL entries in the page array, which may
later crash the kernel.
The simple solution is to call PTR_ERR() before clearing the pointer.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-09-23
In the Linux kernel, the following vulnerability has been resolved:
ceph: always call ceph_shift_unused_folios_left()
The function ceph_process_folio_batch() sets folio_batch entries to
NULL, which is an illegal state. Before folio_batch_release() crashes
due to this API violation, the function ceph_shift_unused_folios_left()
is supposed to remove those NULLs from the array.
However, since commit ce80b76dd327 ("ceph: introduce
ceph_process_folio_batch() method"), this shifting doesn't happen
anymore because the "for" loop got moved to ceph_process_folio_batch(),
and now the `i` variable that remains in ceph_writepages_start()
doesn't get incremented anymore, making the shifting effectively
unreachable much of the time.
Later, commit 1551ec61dc55 ("ceph: introduce ceph_submit_write()
method") added more preconditions for doing the shift, replacing the
`i` check (with something that is still just as broken):
- if ceph_process_folio_batch() fails, shifting never happens
- if ceph_move_dirty_page_in_page_array() was never called (because
ceph_process_folio_batch() has returned early for some of various
reasons), shifting never happens
- if `processed_in_fbatch` is zero (because ceph_process_folio_batch()
has returned early for some of the reasons mentioned above or
because ceph_move_dirty_page_in_page_array() has failed), shifting
never happens
Since those two commits, any problem in ceph_process_folio_batch()
could crash the kernel, e.g. this way:
BUG: kernel NULL pointer dereference, address: 0000000000000034
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: Oops: 0002 [#1] SMP NOPTI
CPU: 172 UID: 0 PID: 2342707 Comm: kworker/u778:8 Not tainted 6.15.10-cm4all1-es #714 NONE
Hardware name: Dell Inc. PowerEdge R7615/0G9DHV, BIOS 1.6.10 12/08/2023
Workqueue: writeback wb_workfn (flush-ceph-1)
RIP: 0010:folios_put_refs+0x85/0x140
Code: 83 c5 01 39 e8 7e 76 48 63 c5 49 8b 5c c4 08 b8 01 00 00 00 4d 85 ed 74 05 41 8b 44 ad 00 48 8b 15 b0 >
RSP: 0018:ffffb880af8db778 EFLAGS: 00010207
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000000000003
RDX: ffffe377cc3b0000 RSI: 0000000000000000 RDI: ffffb880af8db8c0
RBP: 0000000000000000 R08: 000000000000007d R09: 000000000102b86f
R10: 0000000000000001 R11: 00000000000000ac R12: ffffb880af8db8c0
R13: 0000000000000000 R14: 0000000000000000 R15: ffff9bd262c97000
FS: 0000000000000000(0000) GS:ffff9c8efc303000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000034 CR3: 0000000160958004 CR4: 0000000000770ef0
PKRU: 55555554
Call Trace:
<TASK>
ceph_writepages_start+0xeb9/0x1410
The crash can be reproduced easily by changing the
ceph_check_page_before_write() return value to `-E2BIG`.
(Interestingly, the crash happens only if `huge_zero_folio` has
already been allocated; without `huge_zero_folio`,
is_huge_zero_folio(NULL) returns true and folios_put_refs() skips NULL
entries instead of dereferencing them. That makes reproducing the bug
somewhat unreliable. See
https://lore.kernel.org/20250826231626.218675-1-max.kellermann@ionos.com
for a discussion of this detail.)
My suggestion is to move the ceph_shift_unused_folios_left() to right
after ceph_process_folio_batch() to ensure it always gets called to
fix up the illegal folio_batch state.
CVSS Score
5.5
EPSS Score
0.001
Published
2025-09-23