Linux: >> Linux Kernel >> 2.0 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
cifs: fix DFS traversal oops without CONFIG_CIFS_DFS_UPCALL
When compiled with CONFIG_CIFS_DFS_UPCALL disabled, cifs_dfs_d_automount
is NULL. cifs.ko logic for mapping CIFS_FATTR_DFS_REFERRAL attributes to
S_AUTOMOUNT and corresponding dentry flags is retained regardless of
CONFIG_CIFS_DFS_UPCALL, leading to a NULL pointer dereference in
VFS follow_automount() when traversing a DFS referral link:
BUG: kernel NULL pointer dereference, address: 0000000000000000
...
Call Trace:
<TASK>
__traverse_mounts+0xb5/0x220
? cifs_revalidate_mapping+0x65/0xc0 [cifs]
step_into+0x195/0x610
? lookup_fast+0xe2/0xf0
path_lookupat+0x64/0x140
filename_lookup+0xc2/0x140
? __create_object+0x299/0x380
? kmem_cache_alloc+0x119/0x220
? user_path_at_empty+0x31/0x50
user_path_at_empty+0x31/0x50
__x64_sys_chdir+0x2a/0xd0
? exit_to_user_mode_prepare+0xca/0x100
do_syscall_64+0x42/0x90
entry_SYSCALL_64_after_hwframe+0x72/0xdc
This fix adds an inline cifs_dfs_d_automount() {return -EREMOTE} handler
when CONFIG_CIFS_DFS_UPCALL is disabled. An alternative would be to
avoid flagging S_AUTOMOUNT, etc. without CONFIG_CIFS_DFS_UPCALL. This
approach was chosen as it provides more control over the error path.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
btrfs: set_page_extent_mapped after read_folio in btrfs_cont_expand
While trying to get the subpage blocksize tests running, I hit the
following panic on generic/476
assertion failed: PagePrivate(page) && page->private, in fs/btrfs/subpage.c:229
kernel BUG at fs/btrfs/subpage.c:229!
Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
CPU: 1 PID: 1453 Comm: fsstress Not tainted 6.4.0-rc7+ #12
Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20230301gitf80f052277c8-26.fc38 03/01/2023
pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
pc : btrfs_subpage_assert+0xbc/0xf0
lr : btrfs_subpage_assert+0xbc/0xf0
Call trace:
btrfs_subpage_assert+0xbc/0xf0
btrfs_subpage_clear_checked+0x38/0xc0
btrfs_page_clear_checked+0x48/0x98
btrfs_truncate_block+0x5d0/0x6a8
btrfs_cont_expand+0x5c/0x528
btrfs_write_check.isra.0+0xf8/0x150
btrfs_buffered_write+0xb4/0x760
btrfs_do_write_iter+0x2f8/0x4b0
btrfs_file_write_iter+0x1c/0x30
do_iter_readv_writev+0xc8/0x158
do_iter_write+0x9c/0x210
vfs_iter_write+0x24/0x40
iter_file_splice_write+0x224/0x390
direct_splice_actor+0x38/0x68
splice_direct_to_actor+0x12c/0x260
do_splice_direct+0x90/0xe8
generic_copy_file_range+0x50/0x90
vfs_copy_file_range+0x29c/0x470
__arm64_sys_copy_file_range+0xcc/0x498
invoke_syscall.constprop.0+0x80/0xd8
do_el0_svc+0x6c/0x168
el0_svc+0x50/0x1b0
el0t_64_sync_handler+0x114/0x120
el0t_64_sync+0x194/0x198
This happens because during btrfs_cont_expand we'll get a page, set it
as mapped, and if it's not Uptodate we'll read it. However between the
read and re-locking the page we could have called release_folio() on the
page, but left the page in the file mapping. release_folio() can clear
the page private, and thus further down we blow up when we go to modify
the subpage bits.
Fix this by putting the set_page_extent_mapped() after the read. This
is safe because read_folio() will call set_page_extent_mapped() before
it does the read, and then if we clear page private but leave it on the
mapping we're completely safe re-setting set_page_extent_mapped(). With
this patch I can now run generic/476 without panicing.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dsi: Add missing check for alloc_ordered_workqueue
Add check for the return value of alloc_ordered_workqueue as it may return
NULL pointer and cause NULL pointer dereference.
Patchwork: https://patchwork.freedesktop.org/patch/517646/
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
smb: client: fix warning in cifs_smb3_do_mount()
This fixes the following warning reported by kernel test robot
fs/smb/client/cifsfs.c:982 cifs_smb3_do_mount() warn: possible
memory leak of 'cifs_sb'
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
sched/fair: Don't balance task to its current running CPU
We've run into the case that the balancer tries to balance a migration
disabled task and trigger the warning in set_task_cpu() like below:
------------[ cut here ]------------
WARNING: CPU: 7 PID: 0 at kernel/sched/core.c:3115 set_task_cpu+0x188/0x240
Modules linked in: hclgevf xt_CHECKSUM ipt_REJECT nf_reject_ipv4 <...snip>
CPU: 7 PID: 0 Comm: swapper/7 Kdump: loaded Tainted: G O 6.1.0-rc4+ #1
Hardware name: Huawei TaiShan 2280 V2/BC82AMDC, BIOS 2280-V2 CS V5.B221.01 12/09/2021
pstate: 604000c9 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : set_task_cpu+0x188/0x240
lr : load_balance+0x5d0/0xc60
sp : ffff80000803bc70
x29: ffff80000803bc70 x28: ffff004089e190e8 x27: ffff004089e19040
x26: ffff007effcabc38 x25: 0000000000000000 x24: 0000000000000001
x23: ffff80000803be84 x22: 000000000000000c x21: ffffb093e79e2a78
x20: 000000000000000c x19: ffff004089e19040 x18: 0000000000000000
x17: 0000000000001fad x16: 0000000000000030 x15: 0000000000000000
x14: 0000000000000003 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000000400 x9 : ffffb093e4cee530
x8 : 00000000fffffffe x7 : 0000000000ce168a x6 : 000000000000013e
x5 : 00000000ffffffe1 x4 : 0000000000000001 x3 : 0000000000000b2a
x2 : 0000000000000b2a x1 : ffffb093e6d6c510 x0 : 0000000000000001
Call trace:
set_task_cpu+0x188/0x240
load_balance+0x5d0/0xc60
rebalance_domains+0x26c/0x380
_nohz_idle_balance.isra.0+0x1e0/0x370
run_rebalance_domains+0x6c/0x80
__do_softirq+0x128/0x3d8
____do_softirq+0x18/0x24
call_on_irq_stack+0x2c/0x38
do_softirq_own_stack+0x24/0x3c
__irq_exit_rcu+0xcc/0xf4
irq_exit_rcu+0x18/0x24
el1_interrupt+0x4c/0xe4
el1h_64_irq_handler+0x18/0x2c
el1h_64_irq+0x74/0x78
arch_cpu_idle+0x18/0x4c
default_idle_call+0x58/0x194
do_idle+0x244/0x2b0
cpu_startup_entry+0x30/0x3c
secondary_start_kernel+0x14c/0x190
__secondary_switched+0xb0/0xb4
---[ end trace 0000000000000000 ]---
Further investigation shows that the warning is superfluous, the migration
disabled task is just going to be migrated to its current running CPU.
This is because that on load balance if the dst_cpu is not allowed by the
task, we'll re-select a new_dst_cpu as a candidate. If no task can be
balanced to dst_cpu we'll try to balance the task to the new_dst_cpu
instead. In this case when the migration disabled task is not on CPU it
only allows to run on its current CPU, load balance will select its
current CPU as new_dst_cpu and later triggers the warning above.
The new_dst_cpu is chosen from the env->dst_grpmask. Currently it
contains CPUs in sched_group_span() and if we have overlapped groups it's
possible to run into this case. This patch makes env->dst_grpmask of
group_balance_mask() which exclude any CPUs from the busiest group and
solve the issue. For balancing in a domain with no overlapped groups
the behaviour keeps same as before.
CVSS Score
7.8
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
media: az6007: Fix null-ptr-deref in az6007_i2c_xfer()
In az6007_i2c_xfer, msg is controlled by user. When msg[i].buf
is null and msg[i].len is zero, former checks on msg[i].buf would be
passed. Malicious data finally reach az6007_i2c_xfer. If accessing
msg[i].buf[0] without sanity check, null ptr deref would happen.
We add check on msg[i].len to prevent crash.
Similar commit:
commit 0ed554fd769a
("media: dvb-usb: az6027: fix null-ptr-deref in az6027_i2c_xfer()")
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
jfs: jfs_dmap: Validate db_l2nbperpage while mounting
In jfs_dmap.c at line 381, BLKTODMAP is used to get a logical block
number inside dbFree(). db_l2nbperpage, which is the log2 number of
blocks per page, is passed as an argument to BLKTODMAP which uses it
for shifting.
Syzbot reported a shift out-of-bounds crash because db_l2nbperpage is
too big. This happens because the large value is set without any
validation in dbMount() at line 181.
Thus, make sure that db_l2nbperpage is correct while mounting.
Max number of blocks per page = Page size / Min block size
=> log2(Max num_block per page) = log2(Page size / Min block size)
= log2(Page size) - log2(Min block size)
=> Max db_l2nbperpage = L2PSIZE - L2MINBLOCKSIZE
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211_hwsim: Fix possible NULL dereference
In a call to mac80211_hwsim_select_tx_link() the sta pointer might
be NULL, thus need to check that it is not NULL before accessing it.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
wifi: brcmfmac: slab-out-of-bounds read in brcmf_get_assoc_ies()
Fix a slab-out-of-bounds read that occurs in kmemdup() called from
brcmf_get_assoc_ies().
The bug could occur when assoc_info->req_len, data from a URB provided
by a USB device, is bigger than the size of buffer which is defined as
WL_EXTRA_BUF_MAX.
Add the size check for req_len/resp_len of assoc_info.
Found by a modified version of syzkaller.
[ 46.592467][ T7] ==================================================================
[ 46.594687][ T7] BUG: KASAN: slab-out-of-bounds in kmemdup+0x3e/0x50
[ 46.596572][ T7] Read of size 3014656 at addr ffff888019442000 by task kworker/0:1/7
[ 46.598575][ T7]
[ 46.599157][ T7] CPU: 0 PID: 7 Comm: kworker/0:1 Tainted: G O 5.14.0+ #145
[ 46.601333][ T7] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
[ 46.604360][ T7] Workqueue: events brcmf_fweh_event_worker
[ 46.605943][ T7] Call Trace:
[ 46.606584][ T7] dump_stack_lvl+0x8e/0xd1
[ 46.607446][ T7] print_address_description.constprop.0.cold+0x93/0x334
[ 46.608610][ T7] ? kmemdup+0x3e/0x50
[ 46.609341][ T7] kasan_report.cold+0x79/0xd5
[ 46.610151][ T7] ? kmemdup+0x3e/0x50
[ 46.610796][ T7] kasan_check_range+0x14e/0x1b0
[ 46.611691][ T7] memcpy+0x20/0x60
[ 46.612323][ T7] kmemdup+0x3e/0x50
[ 46.612987][ T7] brcmf_get_assoc_ies+0x967/0xf60
[ 46.613904][ T7] ? brcmf_notify_vif_event+0x3d0/0x3d0
[ 46.614831][ T7] ? lock_chain_count+0x20/0x20
[ 46.615683][ T7] ? mark_lock.part.0+0xfc/0x2770
[ 46.616552][ T7] ? lock_chain_count+0x20/0x20
[ 46.617409][ T7] ? mark_lock.part.0+0xfc/0x2770
[ 46.618244][ T7] ? lock_chain_count+0x20/0x20
[ 46.619024][ T7] brcmf_bss_connect_done.constprop.0+0x241/0x2e0
[ 46.620019][ T7] ? brcmf_parse_configure_security.isra.0+0x2a0/0x2a0
[ 46.620818][ T7] ? __lock_acquire+0x181f/0x5790
[ 46.621462][ T7] brcmf_notify_connect_status+0x448/0x1950
[ 46.622134][ T7] ? rcu_read_lock_bh_held+0xb0/0xb0
[ 46.622736][ T7] ? brcmf_cfg80211_join_ibss+0x7b0/0x7b0
[ 46.623390][ T7] ? find_held_lock+0x2d/0x110
[ 46.623962][ T7] ? brcmf_fweh_event_worker+0x19f/0xc60
[ 46.624603][ T7] ? mark_held_locks+0x9f/0xe0
[ 46.625145][ T7] ? lockdep_hardirqs_on_prepare+0x3e0/0x3e0
[ 46.625871][ T7] ? brcmf_cfg80211_join_ibss+0x7b0/0x7b0
[ 46.626545][ T7] brcmf_fweh_call_event_handler.isra.0+0x90/0x100
[ 46.627338][ T7] brcmf_fweh_event_worker+0x557/0xc60
[ 46.627962][ T7] ? brcmf_fweh_call_event_handler.isra.0+0x100/0x100
[ 46.628736][ T7] ? rcu_read_lock_sched_held+0xa1/0xd0
[ 46.629396][ T7] ? rcu_read_lock_bh_held+0xb0/0xb0
[ 46.629970][ T7] ? lockdep_hardirqs_on_prepare+0x273/0x3e0
[ 46.630649][ T7] process_one_work+0x92b/0x1460
[ 46.631205][ T7] ? pwq_dec_nr_in_flight+0x330/0x330
[ 46.631821][ T7] ? rwlock_bug.part.0+0x90/0x90
[ 46.632347][ T7] worker_thread+0x95/0xe00
[ 46.632832][ T7] ? __kthread_parkme+0x115/0x1e0
[ 46.633393][ T7] ? process_one_work+0x1460/0x1460
[ 46.633957][ T7] kthread+0x3a1/0x480
[ 46.634369][ T7] ? set_kthread_struct+0x120/0x120
[ 46.634933][ T7] ret_from_fork+0x1f/0x30
[ 46.635431][ T7]
[ 46.635687][ T7] Allocated by task 7:
[ 46.636151][ T7] kasan_save_stack+0x1b/0x40
[ 46.636628][ T7] __kasan_kmalloc+0x7c/0x90
[ 46.637108][ T7] kmem_cache_alloc_trace+0x19e/0x330
[ 46.637696][ T7] brcmf_cfg80211_attach+0x4a0/0x4040
[ 46.638275][ T7] brcmf_attach+0x389/0xd40
[ 46.638739][ T7] brcmf_usb_probe+0x12de/0x1690
[ 46.639279][ T7] usb_probe_interface+0x2aa/0x760
[ 46.639820][ T7] really_probe+0x205/0xb70
[ 46.640342][ T7] __driver_probe_device+0
---truncated---
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-15
In the Linux kernel, the following vulnerability has been resolved:
fs: jfs: fix shift-out-of-bounds in dbDiscardAG
This should be applied to most URSAN bugs found recently by syzbot,
by guarding the dbMount. As syzbot feeding rubbish into the bmap
descriptor.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-09-15