Security Vulnerabilities
- CVEs Published In May 2025
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix ulist leaks in error paths of qgroup self tests
In the test_no_shared_qgroup() and test_multiple_refs() qgroup self tests,
if we fail to add the tree ref, remove the extent item or remove the
extent ref, we are returning from the test function without freeing the
"old_roots" ulist that was allocated by the previous calls to
btrfs_find_all_roots(). Fix that by calling ulist_free() before returning.
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix inode list leak during backref walking at find_parent_nodes()
During backref walking, at find_parent_nodes(), if we are dealing with a
data extent and we get an error while resolving the indirect backrefs, at
resolve_indirect_refs(), or in the while loop that iterates over the refs
in the direct refs rbtree, we end up leaking the inode lists attached to
the direct refs we have in the direct refs rbtree that were not yet added
to the refs ulist passed as argument to find_parent_nodes(). Since they
were not yet added to the refs ulist and prelim_release() does not free
the lists, on error the caller can only free the lists attached to the
refs that were added to the refs ulist, all the remaining refs get their
inode lists never freed, therefore leaking their memory.
Fix this by having prelim_release() always free any attached inode list
to each ref found in the rbtree, and have find_parent_nodes() set the
ref's inode list to NULL once it transfers ownership of the inode list
to a ref added to the refs ulist passed to find_parent_nodes().
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix inode list leak during backref walking at resolve_indirect_refs()
During backref walking, at resolve_indirect_refs(), if we get an error
we jump to the 'out' label and call ulist_free() on the 'parents' ulist,
which frees all the elements in the ulist - however that does not free
any inode lists that may be attached to elements, through the 'aux' field
of a ulist node, so we end up leaking lists if we have any attached to
the unodes.
Fix this by calling free_leaf_list() instead of ulist_free() when we exit
from resolve_indirect_refs(). The static function free_leaf_list() is
moved up for this to be possible and it's slightly simplified by removing
unnecessary code.
In the Linux kernel, the following vulnerability has been resolved:
mISDN: fix possible memory leak in mISDN_register_device()
Afer commit 1fa5ae857bb1 ("driver core: get rid of struct device's
bus_id string array"), the name of device is allocated dynamically,
add put_device() to give up the reference, so that the name can be
freed in kobject_cleanup() when the refcount is 0.
Set device class before put_device() to avoid null release() function
WARN message in device_release().
In the Linux kernel, the following vulnerability has been resolved:
rose: Fix NULL pointer dereference in rose_send_frame()
The syzkaller reported an issue:
KASAN: null-ptr-deref in range [0x0000000000000380-0x0000000000000387]
CPU: 0 PID: 4069 Comm: kworker/0:15 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
Workqueue: rcu_gp srcu_invoke_callbacks
RIP: 0010:rose_send_frame+0x1dd/0x2f0 net/rose/rose_link.c:101
Call Trace:
<IRQ>
rose_transmit_clear_request+0x1d5/0x290 net/rose/rose_link.c:255
rose_rx_call_request+0x4c0/0x1bc0 net/rose/af_rose.c:1009
rose_loopback_timer+0x19e/0x590 net/rose/rose_loopback.c:111
call_timer_fn+0x1a0/0x6b0 kernel/time/timer.c:1474
expire_timers kernel/time/timer.c:1519 [inline]
__run_timers.part.0+0x674/0xa80 kernel/time/timer.c:1790
__run_timers kernel/time/timer.c:1768 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1803
__do_softirq+0x1d0/0x9c8 kernel/softirq.c:571
[...]
</IRQ>
It triggers NULL pointer dereference when 'neigh->dev->dev_addr' is
called in the rose_send_frame(). It's the first occurrence of the
`neigh` is in rose_loopback_timer() as `rose_loopback_neigh', and
the 'dev' in 'rose_loopback_neigh' is initialized sa nullptr.
It had been fixed by commit 3b3fd068c56e3fbea30090859216a368398e39bf
("rose: Fix Null pointer dereference in rose_send_frame()") ever.
But it's introduced by commit 3c53cd65dece47dd1f9d3a809f32e59d1d87b2b8
("rose: check NULL rose_loopback_neigh->loopback") again.
We fix it by add NULL check in rose_transmit_clear_request(). When
the 'dev' in 'neigh' is NULL, we don't reply the request and just
clear it.
syzkaller don't provide repro, and I provide a syz repro like:
r0 = syz_init_net_socket$bt_sco(0x1f, 0x5, 0x2)
ioctl$sock_inet_SIOCSIFFLAGS(r0, 0x8914, &(0x7f0000000180)={'rose0\x00', 0x201})
r1 = syz_init_net_socket$rose(0xb, 0x5, 0x0)
bind$rose(r1, &(0x7f00000000c0)=@full={0xb, @dev, @null, 0x0, [@null, @null, @netrom, @netrom, @default, @null]}, 0x40)
connect$rose(r1, &(0x7f0000000240)=@short={0xb, @dev={0xbb, 0xbb, 0xbb, 0x1, 0x0}, @remote={0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0x1}, 0x1, @netrom={0xbb, 0xbb, 0xbb, 0xbb, 0xbb, 0x0, 0x0}}, 0x1c)
In the Linux kernel, the following vulnerability has been resolved:
ipvs: fix WARNING in ip_vs_app_net_cleanup()
During the initialization of ip_vs_app_net_init(), if file ip_vs_app
fails to be created, the initialization is successful by default.
Therefore, the ip_vs_app file doesn't be found during the remove in
ip_vs_app_net_cleanup(). It will cause WRNING.
The following is the stack information:
name 'ip_vs_app'
WARNING: CPU: 1 PID: 9 at fs/proc/generic.c:712 remove_proc_entry+0x389/0x460
Modules linked in:
Workqueue: netns cleanup_net
RIP: 0010:remove_proc_entry+0x389/0x460
Call Trace:
<TASK>
ops_exit_list+0x125/0x170
cleanup_net+0x4ea/0xb00
process_one_work+0x9bf/0x1710
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
</TASK>
In the Linux kernel, the following vulnerability has been resolved:
i2c: piix4: Fix adapter not be removed in piix4_remove()
In piix4_probe(), the piix4 adapter will be registered in:
piix4_probe()
piix4_add_adapters_sb800() / piix4_add_adapter()
i2c_add_adapter()
Based on the probed device type, piix4_add_adapters_sb800() or single
piix4_add_adapter() will be called.
For the former case, piix4_adapter_count is set as the number of adapters,
while for antoher case it is not set and kept default *zero*.
When piix4 is removed, piix4_remove() removes the adapters added in
piix4_probe(), basing on the piix4_adapter_count value.
Because the count is zero for the single adapter case, the adapter won't
be removed and makes the sources allocated for adapter leaked, such as
the i2c client and device.
These sources can still be accessed by i2c or bus and cause problems.
An easily reproduced case is that if a new adapter is registered, i2c
will get the leaked adapter and try to call smbus_algorithm, which was
already freed:
Triggered by: rmmod i2c_piix4 && modprobe max31730
BUG: unable to handle page fault for address: ffffffffc053d860
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 3752 Comm: modprobe Tainted: G
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)
RIP: 0010:i2c_default_probe (drivers/i2c/i2c-core-base.c:2259) i2c_core
RSP: 0018:ffff888107477710 EFLAGS: 00000246
...
<TASK>
i2c_detect (drivers/i2c/i2c-core-base.c:2302) i2c_core
__process_new_driver (drivers/i2c/i2c-core-base.c:1336) i2c_core
bus_for_each_dev (drivers/base/bus.c:301)
i2c_for_each_dev (drivers/i2c/i2c-core-base.c:1823) i2c_core
i2c_register_driver (drivers/i2c/i2c-core-base.c:1861) i2c_core
do_one_initcall (init/main.c:1296)
do_init_module (kernel/module/main.c:2455)
...
</TASK>
---[ end trace 0000000000000000 ]---
Fix this problem by correctly set piix4_adapter_count as 1 for the
single adapter so it can be normally removed.
In the Linux kernel, the following vulnerability has been resolved:
blk-mq: Fix kmemleak in blk_mq_init_allocated_queue
There is a kmemleak caused by modprobe null_blk.ko
unreferenced object 0xffff8881acb1f000 (size 1024):
comm "modprobe", pid 836, jiffies 4294971190 (age 27.068s)
hex dump (first 32 bytes):
00 00 00 00 ad 4e ad de ff ff ff ff 00 00 00 00 .....N..........
ff ff ff ff ff ff ff ff 00 53 99 9e ff ff ff ff .........S......
backtrace:
[<000000004a10c249>] kmalloc_node_trace+0x22/0x60
[<00000000648f7950>] blk_mq_alloc_and_init_hctx+0x289/0x350
[<00000000af06de0e>] blk_mq_realloc_hw_ctxs+0x2fe/0x3d0
[<00000000e00c1872>] blk_mq_init_allocated_queue+0x48c/0x1440
[<00000000d16b4e68>] __blk_mq_alloc_disk+0xc8/0x1c0
[<00000000d10c98c3>] 0xffffffffc450d69d
[<00000000b9299f48>] 0xffffffffc4538392
[<0000000061c39ed6>] do_one_initcall+0xd0/0x4f0
[<00000000b389383b>] do_init_module+0x1a4/0x680
[<0000000087cf3542>] load_module+0x6249/0x7110
[<00000000beba61b8>] __do_sys_finit_module+0x140/0x200
[<00000000fdcfff51>] do_syscall_64+0x35/0x80
[<000000003c0f1f71>] entry_SYSCALL_64_after_hwframe+0x46/0xb0
That is because q->ma_ops is set to NULL before blk_release_queue is
called.
blk_mq_init_queue_data
blk_mq_init_allocated_queue
blk_mq_realloc_hw_ctxs
for (i = 0; i < set->nr_hw_queues; i++) {
old_hctx = xa_load(&q->hctx_table, i);
if (!blk_mq_alloc_and_init_hctx(.., i, ..)) [1]
if (!old_hctx)
break;
xa_for_each_start(&q->hctx_table, j, hctx, j)
blk_mq_exit_hctx(q, set, hctx, j); [2]
if (!q->nr_hw_queues) [3]
goto err_hctxs;
err_exit:
q->mq_ops = NULL; [4]
blk_put_queue
blk_release_queue
if (queue_is_mq(q)) [5]
blk_mq_release(q);
[1]: blk_mq_alloc_and_init_hctx failed at i != 0.
[2]: The hctxs allocated by [1] are moved to q->unused_hctx_list and
will be cleaned up in blk_mq_release.
[3]: q->nr_hw_queues is 0.
[4]: Set q->mq_ops to NULL.
[5]: queue_is_mq returns false due to [4]. And blk_mq_release
will not be called. The hctxs in q->unused_hctx_list are leaked.
To fix it, call blk_release_queue in exception path.
In the Linux kernel, the following vulnerability has been resolved:
block: Fix possible memory leak for rq_wb on add_disk failure
kmemleak reported memory leaks in device_add_disk():
kmemleak: 3 new suspected memory leaks
unreferenced object 0xffff88800f420800 (size 512):
comm "modprobe", pid 4275, jiffies 4295639067 (age 223.512s)
hex dump (first 32 bytes):
04 00 00 00 08 00 00 00 01 00 00 00 00 00 00 00 ................
00 e1 f5 05 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000d3662699>] kmalloc_trace+0x26/0x60
[<00000000edc7aadc>] wbt_init+0x50/0x6f0
[<0000000069601d16>] wbt_enable_default+0x157/0x1c0
[<0000000028fc393f>] blk_register_queue+0x2a4/0x420
[<000000007345a042>] device_add_disk+0x6fd/0xe40
[<0000000060e6aab0>] nbd_dev_add+0x828/0xbf0 [nbd]
...
It is because the memory allocated in wbt_enable_default() is not
released in device_add_disk() error path.
Normally, these memory are freed in:
del_gendisk()
rq_qos_exit()
rqos->ops->exit(rqos);
wbt_exit()
So rq_qos_exit() is called to free the rq_wb memory for wbt_init().
However in the error path of device_add_disk(), only
blk_unregister_queue() is called and make rq_wb memory leaked.
Add rq_qos_exit() to the error path to fix it.
In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix WARNING in ip6_route_net_exit_late()
During the initialization of ip6_route_net_init_late(), if file
ipv6_route or rt6_stats fails to be created, the initialization is
successful by default. Therefore, the ipv6_route or rt6_stats file
doesn't be found during the remove in ip6_route_net_exit_late(). It
will cause WRNING.
The following is the stack information:
name 'rt6_stats'
WARNING: CPU: 0 PID: 9 at fs/proc/generic.c:712 remove_proc_entry+0x389/0x460
Modules linked in:
Workqueue: netns cleanup_net
RIP: 0010:remove_proc_entry+0x389/0x460
PKRU: 55555554
Call Trace:
<TASK>
ops_exit_list+0xb0/0x170
cleanup_net+0x4ea/0xb00
process_one_work+0x9bf/0x1710
worker_thread+0x665/0x1080
kthread+0x2e4/0x3a0
ret_from_fork+0x1f/0x30
</TASK>