| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
dma-buf: insert memory barrier before updating num_fences
smp_store_mb() inserts memory barrier after storing operation.
It is different with what the comment is originally aiming so Null
pointer dereference can be happened if memory update is reordered. |
| 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:
__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:
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:
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:
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:
sch_hfsc: Fix qlen accounting bug when using peek in hfsc_enqueue()
When enqueuing the first packet to an HFSC class, hfsc_enqueue() calls the
child qdisc's peek() operation before incrementing sch->q.qlen and
sch->qstats.backlog. If the child qdisc uses qdisc_peek_dequeued(), this may
trigger an immediate dequeue and potential packet drop. In such cases,
qdisc_tree_reduce_backlog() is called, but the HFSC qdisc's qlen and backlog
have not yet been updated, leading to inconsistent queue accounting. This
can leave an empty HFSC class in the active list, causing further
consequences like use-after-free.
This patch fixes the bug by moving the increment of sch->q.qlen and
sch->qstats.backlog before the call to the child qdisc's peek() operation.
This ensures that queue length and backlog are always accurate when packet
drops or dequeues are triggered during the peek. |
| 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:
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. |
| In the Linux kernel, the following vulnerability has been resolved:
xenbus: Use kref to track req lifetime
Marek reported seeing a NULL pointer fault in the xenbus_thread
callstack:
BUG: kernel NULL pointer dereference, address: 0000000000000000
RIP: e030:__wake_up_common+0x4c/0x180
Call Trace:
<TASK>
__wake_up_common_lock+0x82/0xd0
process_msg+0x18e/0x2f0
xenbus_thread+0x165/0x1c0
process_msg+0x18e is req->cb(req). req->cb is set to xs_wake_up(), a
thin wrapper around wake_up(), or xenbus_dev_queue_reply(). It seems
like it was xs_wake_up() in this case.
It seems like req may have woken up the xs_wait_for_reply(), which
kfree()ed the req. When xenbus_thread resumes, it faults on the zero-ed
data.
Linux Device Drivers 2nd edition states:
"Normally, a wake_up call can cause an immediate reschedule to happen,
meaning that other processes might run before wake_up returns."
... which would match the behaviour observed.
Change to keeping two krefs on each request. One for the caller, and
one for xenbus_thread. Each will kref_put() when finished, and the last
will free it.
This use of kref matches the description in
Documentation/core-api/kref.rst |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Verify event formats that have "%*p.."
The trace event verifier checks the formats of trace events to make sure
that they do not point at memory that is not in the trace event itself or
in data that will never be freed. If an event references data that was
allocated when the event triggered and that same data is freed before the
event is read, then the kernel can crash by reading freed memory.
The verifier runs at boot up (or module load) and scans the print formats
of the events and checks their arguments to make sure that dereferenced
pointers are safe. If the format uses "%*p.." the verifier will ignore it,
and that could be dangerous. Cover this case as well.
Also add to the sample code a use case of "%*pbl". |
| In the Linux kernel, the following vulnerability has been resolved:
perf/x86/intel: KVM: Mask PEBS_ENABLE loaded for guest with vCPU's value.
When generating the MSR_IA32_PEBS_ENABLE value that will be loaded on
VM-Entry to a KVM guest, mask the value with the vCPU's desired PEBS_ENABLE
value. Consulting only the host kernel's host vs. guest masks results in
running the guest with PEBS enabled even when the guest doesn't want to use
PEBS. Because KVM uses perf events to proxy the guest virtual PMU, simply
looking at exclude_host can't differentiate between events created by host
userspace, and events created by KVM on behalf of the guest.
Running the guest with PEBS unexpectedly enabled typically manifests as
crashes due to a near-infinite stream of #PFs. E.g. if the guest hasn't
written MSR_IA32_DS_AREA, the CPU will hit page faults on address '0' when
trying to record PEBS events.
The issue is most easily reproduced by running `perf kvm top` from before
commit 7b100989b4f6 ("perf evlist: Remove __evlist__add_default") (after
which, `perf kvm top` effectively stopped using PEBS). The userspace side
of perf creates a guest-only PEBS event, which intel_guest_get_msrs()
misconstrues a guest-*owned* PEBS event.
Arguably, this is a userspace bug, as enabling PEBS on guest-only events
simply cannot work, and userspace can kill VMs in many other ways (there
is no danger to the host). However, even if this is considered to be bad
userspace behavior, there's zero downside to perf/KVM restricting PEBS to
guest-owned events.
Note, commit 854250329c02 ("KVM: x86/pmu: Disable guest PEBS temporarily
in two rare situations") fixed the case where host userspace is profiling
KVM *and* userspace, but missed the case where userspace is profiling only
KVM. |
| In the Linux kernel, the following vulnerability has been resolved:
ksmbd: fix use-after-free in kerberos authentication
Setting sess->user = NULL was introduced to fix the dangling pointer
created by ksmbd_free_user. However, it is possible another thread could
be operating on the session and make use of sess->user after it has been
passed to ksmbd_free_user but before sess->user is set to NULL. |
| In the Linux kernel, the following vulnerability has been resolved:
vxlan: vnifilter: Fix unlocked deletion of default FDB entry
When a VNI is deleted from a VXLAN device in 'vnifilter' mode, the FDB
entry associated with the default remote (assuming one was configured)
is deleted without holding the hash lock. This is wrong and will result
in a warning [1] being generated by the lockdep annotation that was
added by commit ebe642067455 ("vxlan: Create wrappers for FDB lookup").
Reproducer:
# ip link add vx0 up type vxlan dstport 4789 external vnifilter local 192.0.2.1
# bridge vni add vni 10010 remote 198.51.100.1 dev vx0
# bridge vni del vni 10010 dev vx0
Fix by acquiring the hash lock before the deletion and releasing it
afterwards. Blame the original commit that introduced the issue rather
than the one that exposed it.
[1]
WARNING: CPU: 3 PID: 392 at drivers/net/vxlan/vxlan_core.c:417 vxlan_find_mac+0x17f/0x1a0
[...]
RIP: 0010:vxlan_find_mac+0x17f/0x1a0
[...]
Call Trace:
<TASK>
__vxlan_fdb_delete+0xbe/0x560
vxlan_vni_delete_group+0x2ba/0x940
vxlan_vni_del.isra.0+0x15f/0x580
vxlan_process_vni_filter+0x38b/0x7b0
vxlan_vnifilter_process+0x3bb/0x510
rtnetlink_rcv_msg+0x2f7/0xb70
netlink_rcv_skb+0x131/0x360
netlink_unicast+0x426/0x710
netlink_sendmsg+0x75a/0xc20
__sock_sendmsg+0xc1/0x150
____sys_sendmsg+0x5aa/0x7b0
___sys_sendmsg+0xfc/0x180
__sys_sendmsg+0x121/0x1b0
do_syscall_64+0xbb/0x1d0
entry_SYSCALL_64_after_hwframe+0x4b/0x53 |
| In the Linux kernel, the following vulnerability has been resolved:
net_sched: ets: Fix double list add in class with netem as child qdisc
As described in Gerrard's report [1], there are use cases where a netem
child qdisc will make the parent qdisc's enqueue callback reentrant.
In the case of ets, there won't be a UAF, but the code will add the same
classifier to the list twice, which will cause memory corruption.
In addition to checking for qlen being zero, this patch checks whether
the class was already added to the active_list (cl_is_active) before
doing the addition to cater for the reentrant case.
[1] https://lore.kernel.org/netdev/CAHcdcOm+03OD2j6R0=YHKqmy=VgJ8xEOKuP6c7mSgnp-TEJJbw@mail.gmail.com/ |