Linux: >> Linux Kernel >> 4.14.113 Security Vulnerabilities
In the Linux kernel, the following vulnerability has been resolved:
mpls: Use rcu_dereference_rtnl() in mpls_route_input_rcu().
As syzbot reported [0], mpls_route_input_rcu() can be called
from mpls_getroute(), where is under RTNL.
net->mpls.platform_label is only updated under RTNL.
Let's use rcu_dereference_rtnl() in mpls_route_input_rcu() to
silence the splat.
[0]:
WARNING: suspicious RCU usage
6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0 Not tainted
----------------------------
net/mpls/af_mpls.c:84 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by syz.2.4451/17730:
#0: ffffffff9012a3e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff9012a3e8 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x371/0xe90 net/core/rtnetlink.c:6961
stack backtrace:
CPU: 1 UID: 0 PID: 17730 Comm: syz.2.4451 Not tainted 6.15.0-rc7-syzkaller-00082-g5cdb2c77c4c3 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
lockdep_rcu_suspicious+0x166/0x260 kernel/locking/lockdep.c:6865
mpls_route_input_rcu+0x1d4/0x200 net/mpls/af_mpls.c:84
mpls_getroute+0x621/0x1ea0 net/mpls/af_mpls.c:2381
rtnetlink_rcv_msg+0x3c9/0xe90 net/core/rtnetlink.c:6964
netlink_rcv_skb+0x16d/0x440 net/netlink/af_netlink.c:2534
netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
netlink_unicast+0x53a/0x7f0 net/netlink/af_netlink.c:1339
netlink_sendmsg+0x8d1/0xdd0 net/netlink/af_netlink.c:1883
sock_sendmsg_nosec net/socket.c:712 [inline]
__sock_sendmsg net/socket.c:727 [inline]
____sys_sendmsg+0xa98/0xc70 net/socket.c:2566
___sys_sendmsg+0x134/0x1d0 net/socket.c:2620
__sys_sendmmsg+0x200/0x420 net/socket.c:2709
__do_sys_sendmmsg net/socket.c:2736 [inline]
__se_sys_sendmmsg net/socket.c:2733 [inline]
__x64_sys_sendmmsg+0x9c/0x100 net/socket.c:2733
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xcd/0x230 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0a2818e969
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0a28f52038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f0a283b5fa0 RCX: 00007f0a2818e969
RDX: 0000000000000003 RSI: 0000200000000080 RDI: 0000000000000003
RBP: 00007f0a28210ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0a283b5fa0 R15: 00007ffce5e9f268
</TASK>
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
arm64/ptrace: Fix stack-out-of-bounds read in regs_get_kernel_stack_nth()
KASAN reports a stack-out-of-bounds read in regs_get_kernel_stack_nth().
Call Trace:
[ 97.283505] BUG: KASAN: stack-out-of-bounds in regs_get_kernel_stack_nth+0xa8/0xc8
[ 97.284677] Read of size 8 at addr ffff800089277c10 by task 1.sh/2550
[ 97.285732]
[ 97.286067] CPU: 7 PID: 2550 Comm: 1.sh Not tainted 6.6.0+ #11
[ 97.287032] Hardware name: linux,dummy-virt (DT)
[ 97.287815] Call trace:
[ 97.288279] dump_backtrace+0xa0/0x128
[ 97.288946] show_stack+0x20/0x38
[ 97.289551] dump_stack_lvl+0x78/0xc8
[ 97.290203] print_address_description.constprop.0+0x84/0x3c8
[ 97.291159] print_report+0xb0/0x280
[ 97.291792] kasan_report+0x84/0xd0
[ 97.292421] __asan_load8+0x9c/0xc0
[ 97.293042] regs_get_kernel_stack_nth+0xa8/0xc8
[ 97.293835] process_fetch_insn+0x770/0xa30
[ 97.294562] kprobe_trace_func+0x254/0x3b0
[ 97.295271] kprobe_dispatcher+0x98/0xe0
[ 97.295955] kprobe_breakpoint_handler+0x1b0/0x210
[ 97.296774] call_break_hook+0xc4/0x100
[ 97.297451] brk_handler+0x24/0x78
[ 97.298073] do_debug_exception+0xac/0x178
[ 97.298785] el1_dbg+0x70/0x90
[ 97.299344] el1h_64_sync_handler+0xcc/0xe8
[ 97.300066] el1h_64_sync+0x78/0x80
[ 97.300699] kernel_clone+0x0/0x500
[ 97.301331] __arm64_sys_clone+0x70/0x90
[ 97.302084] invoke_syscall+0x68/0x198
[ 97.302746] el0_svc_common.constprop.0+0x11c/0x150
[ 97.303569] do_el0_svc+0x38/0x50
[ 97.304164] el0_svc+0x44/0x1d8
[ 97.304749] el0t_64_sync_handler+0x100/0x130
[ 97.305500] el0t_64_sync+0x188/0x190
[ 97.306151]
[ 97.306475] The buggy address belongs to stack of task 1.sh/2550
[ 97.307461] and is located at offset 0 in frame:
[ 97.308257] __se_sys_clone+0x0/0x138
[ 97.308910]
[ 97.309241] This frame has 1 object:
[ 97.309873] [48, 184) 'args'
[ 97.309876]
[ 97.310749] The buggy address belongs to the virtual mapping at
[ 97.310749] [ffff800089270000, ffff800089279000) created by:
[ 97.310749] dup_task_struct+0xc0/0x2e8
[ 97.313347]
[ 97.313674] The buggy address belongs to the physical page:
[ 97.314604] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14f69a
[ 97.315885] flags: 0x15ffffe00000000(node=1|zone=2|lastcpupid=0xfffff)
[ 97.316957] raw: 015ffffe00000000 0000000000000000 dead000000000122 0000000000000000
[ 97.318207] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
[ 97.319445] page dumped because: kasan: bad access detected
[ 97.320371]
[ 97.320694] Memory state around the buggy address:
[ 97.321511] ffff800089277b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 97.322681] ffff800089277b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 97.323846] >ffff800089277c00: 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00 00 00 00
[ 97.325023] ^
[ 97.325683] ffff800089277c80: 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3
[ 97.326856] ffff800089277d00: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00
This issue seems to be related to the behavior of some gcc compilers and
was also fixed on the s390 architecture before:
commit d93a855c31b7 ("s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()")
As described in that commit, regs_get_kernel_stack_nth() has confirmed that
`addr` is on the stack, so reading the value at `*addr` should be allowed.
Use READ_ONCE_NOCHECK() helper to silence the KASAN check for this case.
[will: Use '*addr' as the argument to READ_ONCE_NOCHECK()]
CVSS Score
7.1
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
fbdev: core: fbcvt: avoid division by 0 in fb_cvt_hperiod()
In fb_find_mode_cvt(), iff mode->refresh somehow happens to be 0x80000000,
cvt.f_refresh will become 0 when multiplying it by 2 due to overflow. It's
then passed to fb_cvt_hperiod(), where it's used as a divider -- division
by 0 will result in kernel oops. Add a sanity check for cvt.f_refresh to
avoid such overflow...
Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
bus: fsl-mc: fix double-free on mc_dev
The blamed commit tried to simplify how the deallocations are done but,
in the process, introduced a double-free on the mc_dev variable.
In case the MC device is a DPRC, a new mc_bus is allocated and the
mc_dev variable is just a reference to one of its fields. In this
circumstance, on the error path only the mc_bus should be freed.
This commit introduces back the following checkpatch warning which is a
false-positive.
WARNING: kfree(NULL) is safe and this check is probably not required
+ if (mc_bus)
+ kfree(mc_bus);
CVSS Score
7.8
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
seg6: Fix validation of nexthop addresses
The kernel currently validates that the length of the provided nexthop
address does not exceed the specified length. This can lead to the
kernel reading uninitialized memory if user space provided a shorter
length than the specified one.
Fix by validating that the provided length exactly matches the specified
one.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
pinctrl: at91: Fix possible out-of-boundary access
at91_gpio_probe() doesn't check that given OF alias is not available or
something went wrong when trying to get it. This might have consequences
when accessing gpio_chips array with that value as an index. Note, that
BUG() can be compiled out and hence won't actually perform the required
checks.
CVSS Score
7.1
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
btrfs: exit after state insertion failure at btrfs_convert_extent_bit()
If insert_state() state failed it returns an error pointer and we call
extent_io_tree_panic() which will trigger a BUG() call. However if
CONFIG_BUG is disabled, which is an uncommon and exotic scenario, then
we fallthrough and call cache_state() which will dereference the error
pointer, resulting in an invalid memory access.
So jump to the 'out' label after calling extent_io_tree_panic(), it also
makes the code more clear besides dealing with the exotic scenario where
CONFIG_BUG is disabled.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-10
In the Linux kernel, the following vulnerability has been resolved:
tty: serial: uartlite: register uart driver in init
When two instances of uart devices are probing, a concurrency race can
occur. If one thread calls uart_register_driver function, which first
allocates and assigns memory to 'uart_state' member of uart_driver
structure, the other instance can bypass uart driver registration and
call ulite_assign. This calls uart_add_one_port, which expects the uart
driver to be fully initialized. This leads to a kernel panic due to a
null pointer dereference:
[ 8.143581] BUG: kernel NULL pointer dereference, address: 00000000000002b8
[ 8.156982] #PF: supervisor write access in kernel mode
[ 8.156984] #PF: error_code(0x0002) - not-present page
[ 8.156986] PGD 0 P4D 0
...
[ 8.180668] RIP: 0010:mutex_lock+0x19/0x30
[ 8.188624] Call Trace:
[ 8.188629] ? __die_body.cold+0x1a/0x1f
[ 8.195260] ? page_fault_oops+0x15c/0x290
[ 8.209183] ? __irq_resolve_mapping+0x47/0x80
[ 8.209187] ? exc_page_fault+0x64/0x140
[ 8.209190] ? asm_exc_page_fault+0x22/0x30
[ 8.209196] ? mutex_lock+0x19/0x30
[ 8.223116] uart_add_one_port+0x60/0x440
[ 8.223122] ? proc_tty_register_driver+0x43/0x50
[ 8.223126] ? tty_register_driver+0x1ca/0x1e0
[ 8.246250] ulite_probe+0x357/0x4b0 [uartlite]
To prevent it, move uart driver registration in to init function. This
will ensure that uart_driver is always registered when probe function
is called.
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-09
In the Linux kernel, the following vulnerability has been resolved:
bcache: fix NULL pointer in cache_set_flush()
1. LINE#1794 - LINE#1887 is some codes about function of
bch_cache_set_alloc().
2. LINE#2078 - LINE#2142 is some codes about function of
register_cache_set().
3. register_cache_set() will call bch_cache_set_alloc() in LINE#2098.
1794 struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
1795 {
...
1860 if (!(c->devices = kcalloc(c->nr_uuids, sizeof(void *), GFP_KERNEL)) ||
1861 mempool_init_slab_pool(&c->search, 32, bch_search_cache) ||
1862 mempool_init_kmalloc_pool(&c->bio_meta, 2,
1863 sizeof(struct bbio) + sizeof(struct bio_vec) *
1864 bucket_pages(c)) ||
1865 mempool_init_kmalloc_pool(&c->fill_iter, 1, iter_size) ||
1866 bioset_init(&c->bio_split, 4, offsetof(struct bbio, bio),
1867 BIOSET_NEED_BVECS|BIOSET_NEED_RESCUER) ||
1868 !(c->uuids = alloc_bucket_pages(GFP_KERNEL, c)) ||
1869 !(c->moving_gc_wq = alloc_workqueue("bcache_gc",
1870 WQ_MEM_RECLAIM, 0)) ||
1871 bch_journal_alloc(c) ||
1872 bch_btree_cache_alloc(c) ||
1873 bch_open_buckets_alloc(c) ||
1874 bch_bset_sort_state_init(&c->sort, ilog2(c->btree_pages)))
1875 goto err;
^^^^^^^^
1876
...
1883 return c;
1884 err:
1885 bch_cache_set_unregister(c);
^^^^^^^^^^^^^^^^^^^^^^^^^^^
1886 return NULL;
1887 }
...
2078 static const char *register_cache_set(struct cache *ca)
2079 {
...
2098 c = bch_cache_set_alloc(&ca->sb);
2099 if (!c)
2100 return err;
^^^^^^^^^^
...
2128 ca->set = c;
2129 ca->set->cache[ca->sb.nr_this_dev] = ca;
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
...
2138 return NULL;
2139 err:
2140 bch_cache_set_unregister(c);
2141 return err;
2142 }
(1) If LINE#1860 - LINE#1874 is true, then do 'goto err'(LINE#1875) and
call bch_cache_set_unregister()(LINE#1885).
(2) As (1) return NULL(LINE#1886), LINE#2098 - LINE#2100 would return.
(3) As (2) has returned, LINE#2128 - LINE#2129 would do *not* give the
value to c->cache[], it means that c->cache[] is NULL.
LINE#1624 - LINE#1665 is some codes about function of cache_set_flush().
As (1), in LINE#1885 call
bch_cache_set_unregister()
---> bch_cache_set_stop()
---> closure_queue()
-.-> cache_set_flush() (as below LINE#1624)
1624 static void cache_set_flush(struct closure *cl)
1625 {
...
1654 for_each_cache(ca, c, i)
1655 if (ca->alloc_thread)
^^
1656 kthread_stop(ca->alloc_thread);
...
1665 }
(4) In LINE#1655 ca is NULL(see (3)) in cache_set_flush() then the
kernel crash occurred as below:
[ 846.712887] bcache: register_cache() error drbd6: cannot allocate memory
[ 846.713242] bcache: register_bcache() error : failed to register device
[ 846.713336] bcache: cache_set_free() Cache set 2f84bdc1-498a-4f2f-98a7-01946bf54287 unregistered
[ 846.713768] BUG: unable to handle kernel NULL pointer dereference at 00000000000009f8
[ 846.714790] PGD 0 P4D 0
[ 846.715129] Oops: 0000 [#1] SMP PTI
[ 846.715472] CPU: 19 PID: 5057 Comm: kworker/19:16 Kdump: loaded Tainted: G OE --------- - - 4.18.0-147.5.1.el8_1.5es.3.x86_64 #1
[ 846.716082] Hardware name: ESPAN GI-25212/X11DPL-i, BIOS 2.1 06/15/2018
[ 846.716451] Workqueue: events cache_set_flush [bcache]
[ 846.716808] RIP: 0010:cache_set_flush+0xc9/0x1b0 [bcache]
[ 846.717155] Code: 00 4c 89 a5 b0 03 00 00 48 8b 85 68 f6 ff ff a8 08 0f 84 88 00 00 00 31 db 66 83 bd 3c f7 ff ff 00 48 8b 85 48 ff ff ff 74 28 <48> 8b b8 f8 09 00 0
---truncated---
CVSS Score
5.5
EPSS Score
0.0
Published
2025-07-09
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_core: Fix use-after-free in vhci_flush()
syzbot reported use-after-free in vhci_flush() without repro. [0]
From the splat, a thread close()d a vhci file descriptor while
its device was being used by iotcl() on another thread.
Once the last fd refcnt is released, vhci_release() calls
hci_unregister_dev(), hci_free_dev(), and kfree() for struct
vhci_data, which is set to hci_dev->dev->driver_data.
The problem is that there is no synchronisation after unlinking
hdev from hci_dev_list in hci_unregister_dev(). There might be
another thread still accessing the hdev which was fetched before
the unlink operation.
We can use SRCU for such synchronisation.
Let's run hci_dev_reset() under SRCU and wait for its completion
in hci_unregister_dev().
Another option would be to restore hci_dev->destruct(), which was
removed in commit 587ae086f6e4 ("Bluetooth: Remove unused
hci-destruct cb"). However, this would not be a good solution, as
we should not run hci_unregister_dev() while there are in-flight
ioctl() requests, which could lead to another data-race KCSAN splat.
Note that other drivers seem to have the same problem, for exmaple,
virtbt_remove().
[0]:
BUG: KASAN: slab-use-after-free in skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]
BUG: KASAN: slab-use-after-free in skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937
Read of size 8 at addr ffff88807cb8d858 by task syz.1.219/6718
CPU: 1 UID: 0 PID: 6718 Comm: syz.1.219 Not tainted 6.16.0-rc1-syzkaller-00196-g08207f42d3ff #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:408 [inline]
print_report+0xd2/0x2b0 mm/kasan/report.c:521
kasan_report+0x118/0x150 mm/kasan/report.c:634
skb_queue_empty_lockless include/linux/skbuff.h:1891 [inline]
skb_queue_purge_reason+0x99/0x360 net/core/skbuff.c:3937
skb_queue_purge include/linux/skbuff.h:3368 [inline]
vhci_flush+0x44/0x50 drivers/bluetooth/hci_vhci.c:69
hci_dev_do_reset net/bluetooth/hci_core.c:552 [inline]
hci_dev_reset+0x420/0x5c0 net/bluetooth/hci_core.c:592
sock_do_ioctl+0xd9/0x300 net/socket.c:1190
sock_ioctl+0x576/0x790 net/socket.c:1311
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
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: 0033:0x7fcf5b98e929
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fcf5c7b9038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fcf5bbb6160 RCX: 00007fcf5b98e929
RDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000009
RBP: 00007fcf5ba10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fcf5bbb6160 R15: 00007ffd6353d528
</TASK>
Allocated by task 6535:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4359
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
vhci_open+0x57/0x360 drivers/bluetooth/hci_vhci.c:635
misc_open+0x2bc/0x330 drivers/char/misc.c:161
chrdev_open+0x4c9/0x5e0 fs/char_dev.c:414
do_dentry_open+0xdf0/0x1970 fs/open.c:964
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:3887 [inline]
path_openat+0x2ee5/0x3830 fs/name
---truncated---
CVSS Score
7.8
EPSS Score
0.0
Published
2025-07-09