| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mm/hugetlb: unshare page tables during VMA split, not before
Currently, __split_vma() triggers hugetlb page table unsharing through
vm_ops->may_split(). This happens before the VMA lock and rmap locks are
taken - which is too early, it allows racing VMA-locked page faults in our
process and racing rmap walks from other processes to cause page tables to
be shared again before we actually perform the split.
Fix it by explicitly calling into the hugetlb unshare logic from
__split_vma() in the same place where THP splitting also happens. At that
point, both the VMA and the rmap(s) are write-locked.
An annoying detail is that we can now call into the helper
hugetlb_unshare_pmds() from two different locking contexts:
1. from hugetlb_split(), holding:
- mmap lock (exclusively)
- VMA lock
- file rmap lock (exclusively)
2. hugetlb_unshare_all_pmds(), which I think is designed to be able to
call us with only the mmap lock held (in shared mode), but currently
only runs while holding mmap lock (exclusively) and VMA lock
Backporting note:
This commit fixes a racy protection that was introduced in commit
b30c14cd6102 ("hugetlb: unshare some PMDs when splitting VMAs"); that
commit claimed to fix an issue introduced in 5.13, but it should actually
also go all the way back.
[jannh@google.com: v2] |
| In the Linux kernel, the following vulnerability has been resolved:
net_sched: prio: fix a race in prio_tune()
Gerrard Tai reported a race condition in PRIO, whenever SFQ perturb timer
fires at the wrong time.
The race is as follows:
CPU 0 CPU 1
[1]: lock root
[2]: qdisc_tree_flush_backlog()
[3]: unlock root
|
| [5]: lock root
| [6]: rehash
| [7]: qdisc_tree_reduce_backlog()
|
[4]: qdisc_put()
This can be abused to underflow a parent's qlen.
Calling qdisc_purge_queue() instead of qdisc_tree_flush_backlog()
should fix the race, because all packets will be purged from the qdisc
before releasing the lock. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: pcm: Fix race of buffer access at PCM OSS layer
The PCM OSS layer tries to clear the buffer with the silence data at
initialization (or reconfiguration) of a stream with the explicit call
of snd_pcm_format_set_silence() with runtime->dma_area. But this may
lead to a UAF because the accessed runtime->dma_area might be freed
concurrently, as it's performed outside the PCM ops.
For avoiding it, move the code into the PCM core and perform it inside
the buffer access lock, so that it won't be changed during the
operation. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: target: iscsi: Fix timeout on deleted connection
NOPIN response timer may expire on a deleted connection and crash with
such logs:
Did not receive response to NOPIN on CID: 0, failing connection for I_T Nexus (null),i,0x00023d000125,iqn.2017-01.com.iscsi.target,t,0x3d
BUG: Kernel NULL pointer dereference on read at 0x00000000
NIP strlcpy+0x8/0xb0
LR iscsit_fill_cxn_timeout_err_stats+0x5c/0xc0 [iscsi_target_mod]
Call Trace:
iscsit_handle_nopin_response_timeout+0xfc/0x120 [iscsi_target_mod]
call_timer_fn+0x58/0x1f0
run_timer_softirq+0x740/0x860
__do_softirq+0x16c/0x420
irq_exit+0x188/0x1c0
timer_interrupt+0x184/0x410
That is because nopin response timer may be re-started on nopin timer
expiration.
Stop nopin timer before stopping the nopin response timer to be sure
that no one of them will be re-started. |
| In the Linux kernel, the following vulnerability has been resolved:
vhost-scsi: protect vq->log_used with vq->mutex
The vhost-scsi completion path may access vq->log_base when vq->log_used is
already set to false.
vhost-thread QEMU-thread
vhost_scsi_complete_cmd_work()
-> vhost_add_used()
-> vhost_add_used_n()
if (unlikely(vq->log_used))
QEMU disables vq->log_used
via VHOST_SET_VRING_ADDR.
mutex_lock(&vq->mutex);
vq->log_used = false now!
mutex_unlock(&vq->mutex);
QEMU gfree(vq->log_base)
log_used()
-> log_write(vq->log_base)
Assuming the VMM is QEMU. The vq->log_base is from QEMU userpace and can be
reclaimed via gfree(). As a result, this causes invalid memory writes to
QEMU userspace.
The control queue path has the same issue. |
| In the Linux kernel, the following vulnerability has been resolved:
orangefs: Do not truncate file size
'len' is used to store the result of i_size_read(), so making 'len'
a size_t results in truncation to 4GiB on 32-bit systems. |
| In the Linux kernel, the following vulnerability has been resolved:
genirq/msi: Store the IOMMU IOVA directly in msi_desc instead of iommu_cookie
The IOMMU translation for MSI message addresses has been a 2-step process,
separated in time:
1) iommu_dma_prepare_msi(): A cookie pointer containing the IOVA address
is stored in the MSI descriptor when an MSI interrupt is allocated.
2) iommu_dma_compose_msi_msg(): this cookie pointer is used to compute a
translated message address.
This has an inherent lifetime problem for the pointer stored in the cookie
that must remain valid between the two steps. However, there is no locking
at the irq layer that helps protect the lifetime. Today, this works under
the assumption that the iommu domain is not changed while MSI interrupts
being programmed. This is true for normal DMA API users within the kernel,
as the iommu domain is attached before the driver is probed and cannot be
changed while a driver is attached.
Classic VFIO type1 also prevented changing the iommu domain while VFIO was
running as it does not support changing the "container" after starting up.
However, iommufd has improved this so that the iommu domain can be changed
during VFIO operation. This potentially allows userspace to directly race
VFIO_DEVICE_ATTACH_IOMMUFD_PT (which calls iommu_attach_group()) and
VFIO_DEVICE_SET_IRQS (which calls into iommu_dma_compose_msi_msg()).
This potentially causes both the cookie pointer and the unlocked call to
iommu_get_domain_for_dev() on the MSI translation path to become UAFs.
Fix the MSI cookie UAF by removing the cookie pointer. The translated IOVA
address is already known during iommu_dma_prepare_msi() and cannot change.
Thus, it can simply be stored as an integer in the MSI descriptor.
The other UAF related to iommu_get_domain_for_dev() will be addressed in
patch "iommu: Make iommu_dma_prepare_msi() into a generic operation" by
using the IOMMU group mutex. |
| In the Linux kernel, the following vulnerability has been resolved:
__legitimize_mnt(): check for MNT_SYNC_UMOUNT should be under mount_lock
... or we risk stealing final mntput from sync umount - raising mnt_count
after umount(2) has verified that victim is not busy, but before it
has set MNT_SYNC_UMOUNT; in that case __legitimize_mnt() doesn't see
that it's safe to quietly undo mnt_count increment and leaves dropping
the reference to caller, where it'll be a full-blown mntput().
Check under mount_lock is needed; leaving the current one done before
taking that makes no sense - it's nowhere near common enough to bother
with. |
| In the Linux kernel, the following vulnerability has been resolved:
net/tipc: fix slab-use-after-free Read in tipc_aead_encrypt_done
Syzbot reported a slab-use-after-free with the following call trace:
==================================================================
BUG: KASAN: slab-use-after-free in tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840
Read of size 8 at addr ffff88807a733000 by task kworker/1:0/25
Call Trace:
kasan_report+0xd9/0x110 mm/kasan/report.c:601
tipc_aead_encrypt_done+0x4bd/0x510 net/tipc/crypto.c:840
crypto_request_complete include/crypto/algapi.h:266
aead_request_complete include/crypto/internal/aead.h:85
cryptd_aead_crypt+0x3b8/0x750 crypto/cryptd.c:772
crypto_request_complete include/crypto/algapi.h:266
cryptd_queue_worker+0x131/0x200 crypto/cryptd.c:181
process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231
Allocated by task 8355:
kzalloc_noprof include/linux/slab.h:778
tipc_crypto_start+0xcc/0x9e0 net/tipc/crypto.c:1466
tipc_init_net+0x2dd/0x430 net/tipc/core.c:72
ops_init+0xb9/0x650 net/core/net_namespace.c:139
setup_net+0x435/0xb40 net/core/net_namespace.c:343
copy_net_ns+0x2f0/0x670 net/core/net_namespace.c:508
create_new_namespaces+0x3ea/0xb10 kernel/nsproxy.c:110
unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:228
ksys_unshare+0x419/0x970 kernel/fork.c:3323
__do_sys_unshare kernel/fork.c:3394
Freed by task 63:
kfree+0x12a/0x3b0 mm/slub.c:4557
tipc_crypto_stop+0x23c/0x500 net/tipc/crypto.c:1539
tipc_exit_net+0x8c/0x110 net/tipc/core.c:119
ops_exit_list+0xb0/0x180 net/core/net_namespace.c:173
cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640
process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231
After freed the tipc_crypto tx by delete namespace, tipc_aead_encrypt_done
may still visit it in cryptd_queue_worker workqueue.
I reproduce this issue by:
ip netns add ns1
ip link add veth1 type veth peer name veth2
ip link set veth1 netns ns1
ip netns exec ns1 tipc bearer enable media eth dev veth1
ip netns exec ns1 tipc node set key this_is_a_master_key master
ip netns exec ns1 tipc bearer disable media eth dev veth1
ip netns del ns1
The key of reproduction is that, simd_aead_encrypt is interrupted, leading
to crypto_simd_usable() return false. Thus, the cryptd_queue_worker is
triggered, and the tipc_crypto tx will be visited.
tipc_disc_timeout
tipc_bearer_xmit_skb
tipc_crypto_xmit
tipc_aead_encrypt
crypto_aead_encrypt
// encrypt()
simd_aead_encrypt
// crypto_simd_usable() is false
child = &ctx->cryptd_tfm->base;
simd_aead_encrypt
crypto_aead_encrypt
// encrypt()
cryptd_aead_encrypt_enqueue
cryptd_aead_enqueue
cryptd_enqueue_request
// trigger cryptd_queue_worker
queue_work_on(smp_processor_id(), cryptd_wq, &cpu_queue->work)
Fix this by holding net reference count before encrypt. |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: Fix use-after-free in cifs_fill_dirent
There is a race condition in the readdir concurrency process, which may
access the rsp buffer after it has been released, triggering the
following KASAN warning.
==================================================================
BUG: KASAN: slab-use-after-free in cifs_fill_dirent+0xb03/0xb60 [cifs]
Read of size 4 at addr ffff8880099b819c by task a.out/342975
CPU: 2 UID: 0 PID: 342975 Comm: a.out Not tainted 6.15.0-rc6+ #240 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.1-2.fc37 04/01/2014
Call Trace:
<TASK>
dump_stack_lvl+0x53/0x70
print_report+0xce/0x640
kasan_report+0xb8/0xf0
cifs_fill_dirent+0xb03/0xb60 [cifs]
cifs_readdir+0x12cb/0x3190 [cifs]
iterate_dir+0x1a1/0x520
__x64_sys_getdents+0x134/0x220
do_syscall_64+0x4b/0x110
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f996f64b9f9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 0d f7 c3 0c 00 f7 d8 64 89 8
RSP: 002b:00007f996f53de78 EFLAGS: 00000207 ORIG_RAX: 000000000000004e
RAX: ffffffffffffffda RBX: 00007f996f53ecdc RCX: 00007f996f64b9f9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007f996f53dea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000207 R12: ffffffffffffff88
R13: 0000000000000000 R14: 00007ffc8cd9a500 R15: 00007f996f51e000
</TASK>
Allocated by task 408:
kasan_save_stack+0x20/0x40
kasan_save_track+0x14/0x30
__kasan_slab_alloc+0x6e/0x70
kmem_cache_alloc_noprof+0x117/0x3d0
mempool_alloc_noprof+0xf2/0x2c0
cifs_buf_get+0x36/0x80 [cifs]
allocate_buffers+0x1d2/0x330 [cifs]
cifs_demultiplex_thread+0x22b/0x2690 [cifs]
kthread+0x394/0x720
ret_from_fork+0x34/0x70
ret_from_fork_asm+0x1a/0x30
Freed by task 342979:
kasan_save_stack+0x20/0x40
kasan_save_track+0x14/0x30
kasan_save_free_info+0x3b/0x60
__kasan_slab_free+0x37/0x50
kmem_cache_free+0x2b8/0x500
cifs_buf_release+0x3c/0x70 [cifs]
cifs_readdir+0x1c97/0x3190 [cifs]
iterate_dir+0x1a1/0x520
__x64_sys_getdents64+0x134/0x220
do_syscall_64+0x4b/0x110
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The buggy address belongs to the object at ffff8880099b8000
which belongs to the cache cifs_request of size 16588
The buggy address is located 412 bytes inside of
freed 16588-byte region [ffff8880099b8000, ffff8880099bc0cc)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x99b8
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000
head: 0080000000000040 ffff888001e03400 0000000000000000 dead000000000001
head: 0000000000000000 0000000000010001 00000000f5000000 0000000000000000
head: 0080000000000003 ffffea0000266e01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8880099b8080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880099b8100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880099b8180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880099b8200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880099b8280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
POC is available in the link [1].
The problem triggering process is as follows:
Process 1 Process 2
-----------------------------------
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
nvmet-tcp: don't restore null sk_state_change
queue->state_change is set as part of nvmet_tcp_set_queue_sock(), but if
the TCP connection isn't established when nvmet_tcp_set_queue_sock() is
called then queue->state_change isn't set and sock->sk->sk_state_change
isn't replaced.
As such we don't need to restore sock->sk->sk_state_change if
queue->state_change is NULL.
This avoids NULL pointer dereferences such as this:
[ 286.462026][ C0] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 286.462814][ C0] #PF: supervisor instruction fetch in kernel mode
[ 286.463796][ C0] #PF: error_code(0x0010) - not-present page
[ 286.464392][ C0] PGD 8000000140620067 P4D 8000000140620067 PUD 114201067 PMD 0
[ 286.465086][ C0] Oops: Oops: 0010 [#1] SMP KASAN PTI
[ 286.465559][ C0] CPU: 0 UID: 0 PID: 1628 Comm: nvme Not tainted 6.15.0-rc2+ #11 PREEMPT(voluntary)
[ 286.466393][ C0] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
[ 286.467147][ C0] RIP: 0010:0x0
[ 286.467420][ C0] Code: Unable to access opcode bytes at 0xffffffffffffffd6.
[ 286.467977][ C0] RSP: 0018:ffff8883ae008580 EFLAGS: 00010246
[ 286.468425][ C0] RAX: 0000000000000000 RBX: ffff88813fd34100 RCX: ffffffffa386cc43
[ 286.469019][ C0] RDX: 1ffff11027fa68b6 RSI: 0000000000000008 RDI: ffff88813fd34100
[ 286.469545][ C0] RBP: ffff88813fd34160 R08: 0000000000000000 R09: ffffed1027fa682c
[ 286.470072][ C0] R10: ffff88813fd34167 R11: 0000000000000000 R12: ffff88813fd344c3
[ 286.470585][ C0] R13: ffff88813fd34112 R14: ffff88813fd34aec R15: ffff888132cdd268
[ 286.471070][ C0] FS: 00007fe3c04c7d80(0000) GS:ffff88840743f000(0000) knlGS:0000000000000000
[ 286.471644][ C0] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 286.472543][ C0] CR2: ffffffffffffffd6 CR3: 000000012daca000 CR4: 00000000000006f0
[ 286.473500][ C0] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 286.474467][ C0] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400
[ 286.475453][ C0] Call Trace:
[ 286.476102][ C0] <IRQ>
[ 286.476719][ C0] tcp_fin+0x2bb/0x440
[ 286.477429][ C0] tcp_data_queue+0x190f/0x4e60
[ 286.478174][ C0] ? __build_skb_around+0x234/0x330
[ 286.478940][ C0] ? rcu_is_watching+0x11/0xb0
[ 286.479659][ C0] ? __pfx_tcp_data_queue+0x10/0x10
[ 286.480431][ C0] ? tcp_try_undo_loss+0x640/0x6c0
[ 286.481196][ C0] ? seqcount_lockdep_reader_access.constprop.0+0x82/0x90
[ 286.482046][ C0] ? kvm_clock_get_cycles+0x14/0x30
[ 286.482769][ C0] ? ktime_get+0x66/0x150
[ 286.483433][ C0] ? rcu_is_watching+0x11/0xb0
[ 286.484146][ C0] tcp_rcv_established+0x6e4/0x2050
[ 286.484857][ C0] ? rcu_is_watching+0x11/0xb0
[ 286.485523][ C0] ? ipv4_dst_check+0x160/0x2b0
[ 286.486203][ C0] ? __pfx_tcp_rcv_established+0x10/0x10
[ 286.486917][ C0] ? lock_release+0x217/0x2c0
[ 286.487595][ C0] tcp_v4_do_rcv+0x4d6/0x9b0
[ 286.488279][ C0] tcp_v4_rcv+0x2af8/0x3e30
[ 286.488904][ C0] ? raw_local_deliver+0x51b/0xad0
[ 286.489551][ C0] ? rcu_is_watching+0x11/0xb0
[ 286.490198][ C0] ? __pfx_tcp_v4_rcv+0x10/0x10
[ 286.490813][ C0] ? __pfx_raw_local_deliver+0x10/0x10
[ 286.491487][ C0] ? __pfx_nf_confirm+0x10/0x10 [nf_conntrack]
[ 286.492275][ C0] ? rcu_is_watching+0x11/0xb0
[ 286.492900][ C0] ip_protocol_deliver_rcu+0x8f/0x370
[ 286.493579][ C0] ip_local_deliver_finish+0x297/0x420
[ 286.494268][ C0] ip_local_deliver+0x168/0x430
[ 286.494867][ C0] ? __pfx_ip_local_deliver+0x10/0x10
[ 286.495498][ C0] ? __pfx_ip_local_deliver_finish+0x10/0x10
[ 286.496204][ C0] ? ip_rcv_finish_core+0x19a/0x1f20
[ 286.496806][ C0] ? lock_release+0x217/0x2c0
[ 286.497414][ C0] ip_rcv+0x455/0x6e0
[ 286.497945][ C0] ? __pfx_ip_rcv+0x10/0x10
[
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net/tls: fix kernel panic when alloc_page failed
We cannot set frag_list to NULL pointer when alloc_page failed.
It will be used in tls_strp_check_queue_ok when the next time
tls_strp_read_sock is called.
This is because we don't reset full_len in tls_strp_flush_anchor_copy()
so the recv path will try to continue handling the partial record
on the next call but we dettached the rcvq from the frag list.
Alternative fix would be to reset full_len.
Unable to handle kernel NULL pointer dereference
at virtual address 0000000000000028
Call trace:
tls_strp_check_rcv+0x128/0x27c
tls_strp_data_ready+0x34/0x44
tls_data_ready+0x3c/0x1f0
tcp_data_ready+0x9c/0xe4
tcp_data_queue+0xf6c/0x12d0
tcp_rcv_established+0x52c/0x798 |
| In the Linux kernel, the following vulnerability has been resolved:
dmaengine: ti: k3-udma: Add missing locking
Recent kernels complain about a missing lock in k3-udma.c when the lock
validator is enabled:
[ 4.128073] WARNING: CPU: 0 PID: 746 at drivers/dma/ti/../virt-dma.h:169 udma_start.isra.0+0x34/0x238
[ 4.137352] CPU: 0 UID: 0 PID: 746 Comm: kworker/0:3 Not tainted 6.12.9-arm64 #28
[ 4.144867] Hardware name: pp-v12 (DT)
[ 4.148648] Workqueue: events udma_check_tx_completion
[ 4.153841] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 4.160834] pc : udma_start.isra.0+0x34/0x238
[ 4.165227] lr : udma_start.isra.0+0x30/0x238
[ 4.169618] sp : ffffffc083cabcf0
[ 4.172963] x29: ffffffc083cabcf0 x28: 0000000000000000 x27: ffffff800001b005
[ 4.180167] x26: ffffffc0812f0000 x25: 0000000000000000 x24: 0000000000000000
[ 4.187370] x23: 0000000000000001 x22: 00000000e21eabe9 x21: ffffff8000fa0670
[ 4.194571] x20: ffffff8001b6bf00 x19: ffffff8000fa0430 x18: ffffffc083b95030
[ 4.201773] x17: 0000000000000000 x16: 00000000f0000000 x15: 0000000000000048
[ 4.208976] x14: 0000000000000048 x13: 0000000000000000 x12: 0000000000000001
[ 4.216179] x11: ffffffc08151a240 x10: 0000000000003ea1 x9 : ffffffc08046ab68
[ 4.223381] x8 : ffffffc083cabac0 x7 : ffffffc081df3718 x6 : 0000000000029fc8
[ 4.230583] x5 : ffffffc0817ee6d8 x4 : 0000000000000bc0 x3 : 0000000000000000
[ 4.237784] x2 : 0000000000000000 x1 : 00000000001fffff x0 : 0000000000000000
[ 4.244986] Call trace:
[ 4.247463] udma_start.isra.0+0x34/0x238
[ 4.251509] udma_check_tx_completion+0xd0/0xdc
[ 4.256076] process_one_work+0x244/0x3fc
[ 4.260129] process_scheduled_works+0x6c/0x74
[ 4.264610] worker_thread+0x150/0x1dc
[ 4.268398] kthread+0xd8/0xe8
[ 4.271492] ret_from_fork+0x10/0x20
[ 4.275107] irq event stamp: 220
[ 4.278363] hardirqs last enabled at (219): [<ffffffc080a27c7c>] _raw_spin_unlock_irq+0x38/0x50
[ 4.287183] hardirqs last disabled at (220): [<ffffffc080a1c154>] el1_dbg+0x24/0x50
[ 4.294879] softirqs last enabled at (182): [<ffffffc080037e68>] handle_softirqs+0x1c0/0x3cc
[ 4.303437] softirqs last disabled at (177): [<ffffffc080010170>] __do_softirq+0x1c/0x28
[ 4.311559] ---[ end trace 0000000000000000 ]---
This commit adds the missing locking. |
| In the Linux kernel, the following vulnerability has been resolved:
can: bcm: add locking for bcm_op runtime updates
The CAN broadcast manager (CAN BCM) can send a sequence of CAN frames via
hrtimer. The content and also the length of the sequence can be changed
resp reduced at runtime where the 'currframe' counter is then set to zero.
Although this appeared to be a safe operation the updates of 'currframe'
can be triggered from user space and hrtimer context in bcm_can_tx().
Anderson Nascimento created a proof of concept that triggered a KASAN
slab-out-of-bounds read access which can be prevented with a spin_lock_bh.
At the rework of bcm_can_tx() the 'count' variable has been moved into
the protected section as this variable can be modified from both contexts
too. |
| In the Linux kernel, the following vulnerability has been resolved:
can: bcm: add missing rcu read protection for procfs content
When the procfs content is generated for a bcm_op which is in the process
to be removed the procfs output might show unreliable data (UAF).
As the removal of bcm_op's is already implemented with rcu handling this
patch adds the missing rcu_read_lock() and makes sure the list entries
are properly removed under rcu protection. |
| In the Linux kernel, the following vulnerability has been resolved:
net_sched: hfsc: Address reentrant enqueue adding class to eltree twice
Savino says:
"We are writing to report that this recent patch
(141d34391abbb315d68556b7c67ad97885407547) [1]
can be bypassed, and a UAF can still occur when HFSC is utilized with
NETEM.
The patch only checks the cl->cl_nactive field to determine whether
it is the first insertion or not [2], but this field is only
incremented by init_vf [3].
By using HFSC_RSC (which uses init_ed) [4], it is possible to bypass the
check and insert the class twice in the eltree.
Under normal conditions, this would lead to an infinite loop in
hfsc_dequeue for the reasons we already explained in this report [5].
However, if TBF is added as root qdisc and it is configured with a
very low rate,
it can be utilized to prevent packets from being dequeued.
This behavior can be exploited to perform subsequent insertions in the
HFSC eltree and cause a UAF."
To fix both the UAF and the infinite loop, with netem as an hfsc child,
check explicitly in hfsc_enqueue whether the class is already in the eltree
whenever the HFSC_RSC flag is set.
[1] https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=141d34391abbb315d68556b7c67ad97885407547
[2] https://elixir.bootlin.com/linux/v6.15-rc5/source/net/sched/sch_hfsc.c#L1572
[3] https://elixir.bootlin.com/linux/v6.15-rc5/source/net/sched/sch_hfsc.c#L677
[4] https://elixir.bootlin.com/linux/v6.15-rc5/source/net/sched/sch_hfsc.c#L1574
[5] https://lore.kernel.org/netdev/8DuRWwfqjoRDLDmBMlIfbrsZg9Gx50DHJc1ilxsEBNe2D6NMoigR_eIRIG0LOjMc3r10nUUZtArXx4oZBIdUfZQrwjcQhdinnMis_0G7VEk=@willsroot.io/T/#u |
| In the Linux kernel, the following vulnerability has been resolved:
openvswitch: Fix unsafe attribute parsing in output_userspace()
This patch replaces the manual Netlink attribute iteration in
output_userspace() with nla_for_each_nested(), which ensures that only
well-formed attributes are processed. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: fix region locking in hash types
Region locking introduced in v5.6-rc4 contained three macros to handle
the region locks: ahash_bucket_start(), ahash_bucket_end() which gave
back the start and end hash bucket values belonging to a given region
lock and ahash_region() which should give back the region lock belonging
to a given hash bucket. The latter was incorrect which can lead to a
race condition between the garbage collector and adding new elements
when a hash type of set is defined with timeouts. |
| In the Linux kernel, the following vulnerability has been resolved:
x86/mm: Eliminate window where TLB flushes may be inadvertently skipped
tl;dr: There is a window in the mm switching code where the new CR3 is
set and the CPU should be getting TLB flushes for the new mm. But
should_flush_tlb() has a bug and suppresses the flush. Fix it by
widening the window where should_flush_tlb() sends an IPI.
Long Version:
=== History ===
There were a few things leading up to this.
First, updating mm_cpumask() was observed to be too expensive, so it was
made lazier. But being lazy caused too many unnecessary IPIs to CPUs
due to the now-lazy mm_cpumask(). So code was added to cull
mm_cpumask() periodically[2]. But that culling was a bit too aggressive
and skipped sending TLB flushes to CPUs that need them. So here we are
again.
=== Problem ===
The too-aggressive code in should_flush_tlb() strikes in this window:
// Turn on IPIs for this CPU/mm combination, but only
// if should_flush_tlb() agrees:
cpumask_set_cpu(cpu, mm_cpumask(next));
next_tlb_gen = atomic64_read(&next->context.tlb_gen);
choose_new_asid(next, next_tlb_gen, &new_asid, &need_flush);
load_new_mm_cr3(need_flush);
// ^ After 'need_flush' is set to false, IPIs *MUST*
// be sent to this CPU and not be ignored.
this_cpu_write(cpu_tlbstate.loaded_mm, next);
// ^ Not until this point does should_flush_tlb()
// become true!
should_flush_tlb() will suppress TLB flushes between load_new_mm_cr3()
and writing to 'loaded_mm', which is a window where they should not be
suppressed. Whoops.
=== Solution ===
Thankfully, the fuzzy "just about to write CR3" window is already marked
with loaded_mm==LOADED_MM_SWITCHING. Simply checking for that state in
should_flush_tlb() is sufficient to ensure that the CPU is targeted with
an IPI.
This will cause more TLB flush IPIs. But the window is relatively small
and I do not expect this to cause any kind of measurable performance
impact.
Update the comment where LOADED_MM_SWITCHING is written since it grew
yet another user.
Peter Z also raised a concern that should_flush_tlb() might not observe
'loaded_mm' and 'is_lazy' in the same order that switch_mm_irqs_off()
writes them. Add a barrier to ensure that they are observed in the
order they are written. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Scrub packet on bpf_redirect_peer
When bpf_redirect_peer is used to redirect packets to a device in
another network namespace, the skb isn't scrubbed. That can lead skb
information from one namespace to be "misused" in another namespace.
As one example, this is causing Cilium to drop traffic when using
bpf_redirect_peer to redirect packets that just went through IPsec
decryption to a container namespace. The following pwru trace shows (1)
the packet path from the host's XFRM layer to the container's XFRM
layer where it's dropped and (2) the number of active skb extensions at
each function.
NETNS MARK IFACE TUPLE FUNC
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm_rcv_cb
.active_extensions = (__u8)2,
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 xfrm4_rcv_cb
.active_extensions = (__u8)2,
4026533547 d00 eth0 10.244.3.124:35473->10.244.2.158:53 gro_cells_receive
.active_extensions = (__u8)2,
[...]
4026533547 0 eth0 10.244.3.124:35473->10.244.2.158:53 skb_do_redirect
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 ip_rcv_core
.active_extensions = (__u8)2,
[...]
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 udp_queue_rcv_one_skb
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_policy_check
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 __xfrm_decode_session
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 security_xfrm_decode_session
.active_extensions = (__u8)2,
4026534999 0 eth0 10.244.3.124:35473->10.244.2.158:53 kfree_skb_reason(SKB_DROP_REASON_XFRM_POLICY)
.active_extensions = (__u8)2,
In this case, there are no XFRM policies in the container's network
namespace so the drop is unexpected. When we decrypt the IPsec packet,
the XFRM state used for decryption is set in the skb extensions. This
information is preserved across the netns switch. When we reach the
XFRM policy check in the container's netns, __xfrm_policy_check drops
the packet with LINUX_MIB_XFRMINNOPOLS because a (container-side) XFRM
policy can't be found that matches the (host-side) XFRM state used for
decryption.
This patch fixes this by scrubbing the packet when using
bpf_redirect_peer, as is done on typical netns switches via veth
devices except skb->mark and skb->tstamp are not zeroed. |
