Security Vulnerabilities
- CVEs Published In 2024
In the Linux kernel, the following vulnerability has been resolved:
ubi: fastmap: Fix duplicate slab cache names while attaching
Since commit 4c39529663b9 ("slab: Warn on duplicate cache names when
DEBUG_VM=y"), the duplicate slab cache names can be detected and a
kernel WARNING is thrown out.
In UBI fast attaching process, alloc_ai() could be invoked twice
with the same slab cache name 'ubi_aeb_slab_cache', which will trigger
following warning messages:
kmem_cache of name 'ubi_aeb_slab_cache' already exists
WARNING: CPU: 0 PID: 7519 at mm/slab_common.c:107
__kmem_cache_create_args+0x100/0x5f0
Modules linked in: ubi(+) nandsim [last unloaded: nandsim]
CPU: 0 UID: 0 PID: 7519 Comm: modprobe Tainted: G 6.12.0-rc2
RIP: 0010:__kmem_cache_create_args+0x100/0x5f0
Call Trace:
__kmem_cache_create_args+0x100/0x5f0
alloc_ai+0x295/0x3f0 [ubi]
ubi_attach+0x3c3/0xcc0 [ubi]
ubi_attach_mtd_dev+0x17cf/0x3fa0 [ubi]
ubi_init+0x3fb/0x800 [ubi]
do_init_module+0x265/0x7d0
__x64_sys_finit_module+0x7a/0xc0
The problem could be easily reproduced by loading UBI device by fastmap
with CONFIG_DEBUG_VM=y.
Fix it by using different slab names for alloc_ai() callers.
In the Linux kernel, the following vulnerability has been resolved:
NFSv4.0: Fix a use-after-free problem in the asynchronous open()
Yang Erkun reports that when two threads are opening files at the same
time, and are forced to abort before a reply is seen, then the call to
nfs_release_seqid() in nfs4_opendata_free() can result in a
use-after-free of the pointer to the defunct rpc task of the other
thread.
The fix is to ensure that if the RPC call is aborted before the call to
nfs_wait_on_sequence() is complete, then we must call nfs_release_seqid()
in nfs4_open_release() before the rpc_task is freed.
In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: make sure cache entry active before cache_show
The function `c_show` was called with protection from RCU. This only
ensures that `cp` will not be freed. Therefore, the reference count for
`cp` can drop to zero, which will trigger a refcount use-after-free
warning when `cache_get` is called. To resolve this issue, use
`cache_get_rcu` to ensure that `cp` remains active.
------------[ cut here ]------------
refcount_t: addition on 0; use-after-free.
WARNING: CPU: 7 PID: 822 at lib/refcount.c:25
refcount_warn_saturate+0xb1/0x120
CPU: 7 UID: 0 PID: 822 Comm: cat Not tainted 6.12.0-rc3+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.16.1-2.fc37 04/01/2014
RIP: 0010:refcount_warn_saturate+0xb1/0x120
Call Trace:
<TASK>
c_show+0x2fc/0x380 [sunrpc]
seq_read_iter+0x589/0x770
seq_read+0x1e5/0x270
proc_reg_read+0xe1/0x140
vfs_read+0x125/0x530
ksys_read+0xc1/0x160
do_syscall_64+0x5f/0x170
entry_SYSCALL_64_after_hwframe+0x76/0x7e
In the Linux kernel, the following vulnerability has been resolved:
ipc: fix memleak if msg_init_ns failed in create_ipc_ns
Percpu memory allocation may failed during create_ipc_ns however this
fail is not handled properly since ipc sysctls and mq sysctls is not
released properly. Fix this by release these two resource when failure.
Here is the kmemleak stack when percpu failed:
unreferenced object 0xffff88819de2a600 (size 512):
comm "shmem_2nstest", pid 120711, jiffies 4300542254
hex dump (first 32 bytes):
60 aa 9d 84 ff ff ff ff fc 18 48 b2 84 88 ff ff `.........H.....
04 00 00 00 a4 01 00 00 20 e4 56 81 ff ff ff ff ........ .V.....
backtrace (crc be7cba35):
[<ffffffff81b43f83>] __kmalloc_node_track_caller_noprof+0x333/0x420
[<ffffffff81a52e56>] kmemdup_noprof+0x26/0x50
[<ffffffff821b2f37>] setup_mq_sysctls+0x57/0x1d0
[<ffffffff821b29cc>] copy_ipcs+0x29c/0x3b0
[<ffffffff815d6a10>] create_new_namespaces+0x1d0/0x920
[<ffffffff815d7449>] copy_namespaces+0x2e9/0x3e0
[<ffffffff815458f3>] copy_process+0x29f3/0x7ff0
[<ffffffff8154b080>] kernel_clone+0xc0/0x650
[<ffffffff8154b6b1>] __do_sys_clone+0xa1/0xe0
[<ffffffff843df8ff>] do_syscall_64+0xbf/0x1c0
[<ffffffff846000b0>] entry_SYSCALL_64_after_hwframe+0x4b/0x53
In the Linux kernel, the following vulnerability has been resolved:
smb: During unmount, ensure all cached dir instances drop their dentry
The unmount process (cifs_kill_sb() calling close_all_cached_dirs()) can
race with various cached directory operations, which ultimately results
in dentries not being dropped and these kernel BUGs:
BUG: Dentry ffff88814f37e358{i=1000000000080,n=/} still in use (2) [unmount of cifs cifs]
VFS: Busy inodes after unmount of cifs (cifs)
------------[ cut here ]------------
kernel BUG at fs/super.c:661!
This happens when a cfid is in the process of being cleaned up when, and
has been removed from the cfids->entries list, including:
- Receiving a lease break from the server
- Server reconnection triggers invalidate_all_cached_dirs(), which
removes all the cfids from the list
- The laundromat thread decides to expire an old cfid.
To solve these problems, dropping the dentry is done in queued work done
in a newly-added cfid_put_wq workqueue, and close_all_cached_dirs()
flushes that workqueue after it drops all the dentries of which it's
aware. This is a global workqueue (rather than scoped to a mount), but
the queued work is minimal.
The final cleanup work for cleaning up a cfid is performed via work
queued in the serverclose_wq workqueue; this is done separate from
dropping the dentries so that close_all_cached_dirs() doesn't block on
any server operations.
Both of these queued works expect to invoked with a cfid reference and
a tcon reference to avoid those objects from being freed while the work
is ongoing.
While we're here, add proper locking to close_all_cached_dirs(), and
locking around the freeing of cfid->dentry.
In the Linux kernel, the following vulnerability has been resolved:
net: sched: fix ordering of qlen adjustment
Changes to sch->q.qlen around qdisc_tree_reduce_backlog() need to happen
_before_ a call to said function because otherwise it may fail to notify
parent qdiscs when the child is about to become empty.
In the Linux kernel, the following vulnerability has been resolved:
sh: intc: Fix use-after-free bug in register_intc_controller()
In the error handling for this function, d is freed without ever
removing it from intc_list which would lead to a use after free.
To fix this, let's only add it to the list after everything has
succeeded.
In the Linux kernel, the following vulnerability has been resolved:
block, bfq: fix bfqq uaf in bfq_limit_depth()
Set new allocated bfqq to bic or remove freed bfqq from bic are both
protected by bfqd->lock, however bfq_limit_depth() is deferencing bfqq
from bic without the lock, this can lead to UAF if the io_context is
shared by multiple tasks.
For example, test bfq with io_uring can trigger following UAF in v6.6:
==================================================================
BUG: KASAN: slab-use-after-free in bfqq_group+0x15/0x50
Call Trace:
<TASK>
dump_stack_lvl+0x47/0x80
print_address_description.constprop.0+0x66/0x300
print_report+0x3e/0x70
kasan_report+0xb4/0xf0
bfqq_group+0x15/0x50
bfqq_request_over_limit+0x130/0x9a0
bfq_limit_depth+0x1b5/0x480
__blk_mq_alloc_requests+0x2b5/0xa00
blk_mq_get_new_requests+0x11d/0x1d0
blk_mq_submit_bio+0x286/0xb00
submit_bio_noacct_nocheck+0x331/0x400
__block_write_full_folio+0x3d0/0x640
writepage_cb+0x3b/0xc0
write_cache_pages+0x254/0x6c0
write_cache_pages+0x254/0x6c0
do_writepages+0x192/0x310
filemap_fdatawrite_wbc+0x95/0xc0
__filemap_fdatawrite_range+0x99/0xd0
filemap_write_and_wait_range.part.0+0x4d/0xa0
blkdev_read_iter+0xef/0x1e0
io_read+0x1b6/0x8a0
io_issue_sqe+0x87/0x300
io_wq_submit_work+0xeb/0x390
io_worker_handle_work+0x24d/0x550
io_wq_worker+0x27f/0x6c0
ret_from_fork_asm+0x1b/0x30
</TASK>
Allocated by task 808602:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
__kasan_slab_alloc+0x83/0x90
kmem_cache_alloc_node+0x1b1/0x6d0
bfq_get_queue+0x138/0xfa0
bfq_get_bfqq_handle_split+0xe3/0x2c0
bfq_init_rq+0x196/0xbb0
bfq_insert_request.isra.0+0xb5/0x480
bfq_insert_requests+0x156/0x180
blk_mq_insert_request+0x15d/0x440
blk_mq_submit_bio+0x8a4/0xb00
submit_bio_noacct_nocheck+0x331/0x400
__blkdev_direct_IO_async+0x2dd/0x330
blkdev_write_iter+0x39a/0x450
io_write+0x22a/0x840
io_issue_sqe+0x87/0x300
io_wq_submit_work+0xeb/0x390
io_worker_handle_work+0x24d/0x550
io_wq_worker+0x27f/0x6c0
ret_from_fork+0x2d/0x50
ret_from_fork_asm+0x1b/0x30
Freed by task 808589:
kasan_save_stack+0x1e/0x40
kasan_set_track+0x21/0x30
kasan_save_free_info+0x27/0x40
__kasan_slab_free+0x126/0x1b0
kmem_cache_free+0x10c/0x750
bfq_put_queue+0x2dd/0x770
__bfq_insert_request.isra.0+0x155/0x7a0
bfq_insert_request.isra.0+0x122/0x480
bfq_insert_requests+0x156/0x180
blk_mq_dispatch_plug_list+0x528/0x7e0
blk_mq_flush_plug_list.part.0+0xe5/0x590
__blk_flush_plug+0x3b/0x90
blk_finish_plug+0x40/0x60
do_writepages+0x19d/0x310
filemap_fdatawrite_wbc+0x95/0xc0
__filemap_fdatawrite_range+0x99/0xd0
filemap_write_and_wait_range.part.0+0x4d/0xa0
blkdev_read_iter+0xef/0x1e0
io_read+0x1b6/0x8a0
io_issue_sqe+0x87/0x300
io_wq_submit_work+0xeb/0x390
io_worker_handle_work+0x24d/0x550
io_wq_worker+0x27f/0x6c0
ret_from_fork+0x2d/0x50
ret_from_fork_asm+0x1b/0x30
Fix the problem by protecting bic_to_bfqq() with bfqd->lock.
In the Linux kernel, the following vulnerability has been resolved:
nfs/blocklayout: Don't attempt unregister for invalid block device
Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key
unregistration") an unmount of a pNFS SCSI layout-enabled NFS may
dereference a NULL block_device in:
bl_unregister_scsi+0x16/0xe0 [blocklayoutdriver]
bl_free_device+0x70/0x80 [blocklayoutdriver]
bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver]
nfs4_put_deviceid_node+0x60/0xc0 [nfsv4]
nfs4_deviceid_purge_client+0x132/0x190 [nfsv4]
unset_pnfs_layoutdriver+0x59/0x60 [nfsv4]
nfs4_destroy_server+0x36/0x70 [nfsv4]
nfs_free_server+0x23/0xe0 [nfs]
deactivate_locked_super+0x30/0xb0
cleanup_mnt+0xba/0x150
task_work_run+0x59/0x90
syscall_exit_to_user_mode+0x217/0x220
do_syscall_64+0x8e/0x160
This happens because even though we were able to create the
nfs4_deviceid_node, the lookup for the device was unable to attach the
block device to the pnfs_block_dev.
If we never found a block device to register, we can avoid this case with
the PNFS_BDEV_REGISTERED flag. Move the deref behind the test for the
flag.
In the Linux kernel, the following vulnerability has been resolved:
sunrpc: fix one UAF issue caused by sunrpc kernel tcp socket
BUG: KASAN: slab-use-after-free in tcp_write_timer_handler+0x156/0x3e0
Read of size 1 at addr ffff888111f322cd by task swapper/0/0
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted 6.12.0-rc4-dirty #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1
Call Trace:
<IRQ>
dump_stack_lvl+0x68/0xa0
print_address_description.constprop.0+0x2c/0x3d0
print_report+0xb4/0x270
kasan_report+0xbd/0xf0
tcp_write_timer_handler+0x156/0x3e0
tcp_write_timer+0x66/0x170
call_timer_fn+0xfb/0x1d0
__run_timers+0x3f8/0x480
run_timer_softirq+0x9b/0x100
handle_softirqs+0x153/0x390
__irq_exit_rcu+0x103/0x120
irq_exit_rcu+0xe/0x20
sysvec_apic_timer_interrupt+0x76/0x90
</IRQ>
<TASK>
asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:default_idle+0xf/0x20
Code: 4c 01 c7 4c 29 c2 e9 72 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90
90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 33 f8 25 00 fb f4 <fa> c3 cc cc cc
cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90
RSP: 0018:ffffffffa2007e28 EFLAGS: 00000242
RAX: 00000000000f3b31 RBX: 1ffffffff4400fc7 RCX: ffffffffa09c3196
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff9f00590f
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed102360835d
R10: ffff88811b041aeb R11: 0000000000000001 R12: 0000000000000000
R13: ffffffffa202d7c0 R14: 0000000000000000 R15: 00000000000147d0
default_idle_call+0x6b/0xa0
cpuidle_idle_call+0x1af/0x1f0
do_idle+0xbc/0x130
cpu_startup_entry+0x33/0x40
rest_init+0x11f/0x210
start_kernel+0x39a/0x420
x86_64_start_reservations+0x18/0x30
x86_64_start_kernel+0x97/0xa0
common_startup_64+0x13e/0x141
</TASK>
Allocated by task 595:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
__kasan_slab_alloc+0x87/0x90
kmem_cache_alloc_noprof+0x12b/0x3f0
copy_net_ns+0x94/0x380
create_new_namespaces+0x24c/0x500
unshare_nsproxy_namespaces+0x75/0xf0
ksys_unshare+0x24e/0x4f0
__x64_sys_unshare+0x1f/0x30
do_syscall_64+0x70/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Freed by task 100:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x54/0x70
kmem_cache_free+0x156/0x5d0
cleanup_net+0x5d3/0x670
process_one_work+0x776/0xa90
worker_thread+0x2e2/0x560
kthread+0x1a8/0x1f0
ret_from_fork+0x34/0x60
ret_from_fork_asm+0x1a/0x30
Reproduction script:
mkdir -p /mnt/nfsshare
mkdir -p /mnt/nfs/netns_1
mkfs.ext4 /dev/sdb
mount /dev/sdb /mnt/nfsshare
systemctl restart nfs-server
chmod 777 /mnt/nfsshare
exportfs -i -o rw,no_root_squash *:/mnt/nfsshare
ip netns add netns_1
ip link add name veth_1_peer type veth peer veth_1
ifconfig veth_1_peer 11.11.0.254 up
ip link set veth_1 netns netns_1
ip netns exec netns_1 ifconfig veth_1 11.11.0.1
ip netns exec netns_1 /root/iptables -A OUTPUT -d 11.11.0.254 -p tcp \
--tcp-flags FIN FIN -j DROP
(note: In my environment, a DESTROY_CLIENTID operation is always sent
immediately, breaking the nfs tcp connection.)
ip netns exec netns_1 timeout -s 9 300 mount -t nfs -o proto=tcp,vers=4.1 \
11.11.0.254:/mnt/nfsshare /mnt/nfs/netns_1
ip netns del netns_1
The reason here is that the tcp socket in netns_1 (nfs side) has been
shutdown and closed (done in xs_destroy), but the FIN message (with ack)
is discarded, and the nfsd side keeps sending retransmission messages.
As a result, when the tcp sock in netns_1 processes the received message,
it sends the message (FIN message) in the sending queue, and the tcp timer
is re-established. When the network namespace is deleted, the net structure
accessed by tcp's timer handler function causes problems.
To fix this problem, let's hold netns refcnt for the tcp kernel socket as
done in other modules. This is an ugly hack which can easily be backported
to earlier kernels. A proper fix which cleans up the interfaces will
follow, but may not be so easy to backport.