| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
dst: fix races in rt6_uncached_list_del() and rt_del_uncached_list()
syzbot was able to crash the kernel in rt6_uncached_list_flush_dev()
in an interesting way [1]
Crash happens in list_del_init()/INIT_LIST_HEAD() while writing
list->prev, while the prior write on list->next went well.
static inline void INIT_LIST_HEAD(struct list_head *list)
{
WRITE_ONCE(list->next, list); // This went well
WRITE_ONCE(list->prev, list); // Crash, @list has been freed.
}
Issue here is that rt6_uncached_list_del() did not attempt to lock
ul->lock, as list_empty(&rt->dst.rt_uncached) returned
true because the WRITE_ONCE(list->next, list) happened on the other CPU.
We might use list_del_init_careful() and list_empty_careful(),
or make sure rt6_uncached_list_del() always grabs the spinlock
whenever rt->dst.rt_uncached_list has been set.
A similar fix is neeed for IPv4.
[1]
BUG: KASAN: slab-use-after-free in INIT_LIST_HEAD include/linux/list.h:46 [inline]
BUG: KASAN: slab-use-after-free in list_del_init include/linux/list.h:296 [inline]
BUG: KASAN: slab-use-after-free in rt6_uncached_list_flush_dev net/ipv6/route.c:191 [inline]
BUG: KASAN: slab-use-after-free in rt6_disable_ip+0x633/0x730 net/ipv6/route.c:5020
Write of size 8 at addr ffff8880294cfa78 by task kworker/u8:14/3450
CPU: 0 UID: 0 PID: 3450 Comm: kworker/u8:14 Tainted: G L syzkaller #0 PREEMPT_{RT,(full)}
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: netns cleanup_net
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description mm/kasan/report.c:378 [inline]
print_report+0xca/0x240 mm/kasan/report.c:482
kasan_report+0x118/0x150 mm/kasan/report.c:595
INIT_LIST_HEAD include/linux/list.h:46 [inline]
list_del_init include/linux/list.h:296 [inline]
rt6_uncached_list_flush_dev net/ipv6/route.c:191 [inline]
rt6_disable_ip+0x633/0x730 net/ipv6/route.c:5020
addrconf_ifdown+0x143/0x18a0 net/ipv6/addrconf.c:3853
addrconf_notify+0x1bc/0x1050 net/ipv6/addrconf.c:-1
notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2268 [inline]
call_netdevice_notifiers net/core/dev.c:2282 [inline]
netif_close_many+0x29c/0x410 net/core/dev.c:1785
unregister_netdevice_many_notify+0xb50/0x2330 net/core/dev.c:12353
ops_exit_rtnl_list net/core/net_namespace.c:187 [inline]
ops_undo_list+0x3dc/0x990 net/core/net_namespace.c:248
cleanup_net+0x4de/0x7b0 net/core/net_namespace.c:696
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246
</TASK>
Allocated by task 803:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4953 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_noprof+0x18d/0x6c0 mm/slub.c:5270
dst_alloc+0x105/0x170 net/core/dst.c:89
ip6_dst_alloc net/ipv6/route.c:342 [inline]
icmp6_dst_alloc+0x75/0x460 net/ipv6/route.c:3333
mld_sendpack+0x683/0xe60 net/ipv6/mcast.c:1844
mld_send_cr net/ipv6/mcast.c:2154 [inline]
mld_ifc_work+0x83e/0xd60 net/ipv6/mcast.c:2693
process_one_work kernel/workqueue.c:3257 [inline]
process_scheduled_works+0xad1/0x1770 kernel/workqueue.c:3340
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3421
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entr
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
ip6_tunnel: use skb_vlan_inet_prepare() in __ip6_tnl_rcv()
Blamed commit did not take care of VLAN encapsulations
as spotted by syzbot [1].
Use skb_vlan_inet_prepare() instead of pskb_inet_may_pull().
[1]
BUG: KMSAN: uninit-value in __INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]
BUG: KMSAN: uninit-value in INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]
BUG: KMSAN: uninit-value in IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321
__INET_ECN_decapsulate include/net/inet_ecn.h:253 [inline]
INET_ECN_decapsulate include/net/inet_ecn.h:275 [inline]
IP6_ECN_decapsulate+0x7a8/0x1fa0 include/net/inet_ecn.h:321
ip6ip6_dscp_ecn_decapsulate+0x16f/0x1b0 net/ipv6/ip6_tunnel.c:729
__ip6_tnl_rcv+0xed9/0x1b50 net/ipv6/ip6_tunnel.c:860
ip6_tnl_rcv+0xc3/0x100 net/ipv6/ip6_tunnel.c:903
gre_rcv+0x1529/0x1b90 net/ipv6/ip6_gre.c:-1
ip6_protocol_deliver_rcu+0x1c89/0x2c60 net/ipv6/ip6_input.c:438
ip6_input_finish+0x1f4/0x4a0 net/ipv6/ip6_input.c:489
NF_HOOK include/linux/netfilter.h:318 [inline]
ip6_input+0x9c/0x330 net/ipv6/ip6_input.c:500
ip6_mc_input+0x7ca/0xc10 net/ipv6/ip6_input.c:590
dst_input include/net/dst.h:474 [inline]
ip6_rcv_finish+0x958/0x990 net/ipv6/ip6_input.c:79
NF_HOOK include/linux/netfilter.h:318 [inline]
ipv6_rcv+0xf1/0x3c0 net/ipv6/ip6_input.c:311
__netif_receive_skb_one_core net/core/dev.c:6139 [inline]
__netif_receive_skb+0x1df/0xac0 net/core/dev.c:6252
netif_receive_skb_internal net/core/dev.c:6338 [inline]
netif_receive_skb+0x57/0x630 net/core/dev.c:6397
tun_rx_batched+0x1df/0x980 drivers/net/tun.c:1485
tun_get_user+0x5c0e/0x6c60 drivers/net/tun.c:1953
tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0xbe2/0x15d0 fs/read_write.c:686
ksys_write fs/read_write.c:738 [inline]
__do_sys_write fs/read_write.c:749 [inline]
__se_sys_write fs/read_write.c:746 [inline]
__x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Uninit was created at:
slab_post_alloc_hook mm/slub.c:4960 [inline]
slab_alloc_node mm/slub.c:5263 [inline]
kmem_cache_alloc_node_noprof+0x9e7/0x17a0 mm/slub.c:5315
kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:586
__alloc_skb+0x805/0x1040 net/core/skbuff.c:690
alloc_skb include/linux/skbuff.h:1383 [inline]
alloc_skb_with_frags+0xc5/0xa60 net/core/skbuff.c:6712
sock_alloc_send_pskb+0xacc/0xc60 net/core/sock.c:2995
tun_alloc_skb drivers/net/tun.c:1461 [inline]
tun_get_user+0x1142/0x6c60 drivers/net/tun.c:1794
tun_chr_write_iter+0x3e9/0x5c0 drivers/net/tun.c:1999
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0xbe2/0x15d0 fs/read_write.c:686
ksys_write fs/read_write.c:738 [inline]
__do_sys_write fs/read_write.c:749 [inline]
__se_sys_write fs/read_write.c:746 [inline]
__x64_sys_write+0x1fb/0x4d0 fs/read_write.c:746
x64_sys_call+0x30ab/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
CPU: 0 UID: 0 PID: 6465 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(none)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 |
| In the Linux kernel, the following vulnerability has been resolved:
lib/buildid: use __kernel_read() for sleepable context
Prevent a "BUG: unable to handle kernel NULL pointer dereference in
filemap_read_folio".
For the sleepable context, convert freader to use __kernel_read() instead
of direct page cache access via read_cache_folio(). This simplifies the
faultable code path by using the standard kernel file reading interface
which handles all the complexity of reading file data.
At the moment we are not changing the code for non-sleepable context which
uses filemap_get_folio() and only succeeds if the target folios are
already in memory and up-to-date. The reason is to keep the patch simple
and easier to backport to stable kernels.
Syzbot repro does not crash the kernel anymore and the selftests run
successfully.
In the follow up we will make __kernel_read() with IOCB_NOWAIT work for
non-sleepable contexts. In addition, I would like to replace the
secretmem check with a more generic approach and will add fstest for the
buildid code. |
| In the Linux kernel, the following vulnerability has been resolved:
macvlan: fix possible UAF in macvlan_forward_source()
Add RCU protection on (struct macvlan_source_entry)->vlan.
Whenever macvlan_hash_del_source() is called, we must clear
entry->vlan pointer before RCU grace period starts.
This allows macvlan_forward_source() to skip over
entries queued for freeing.
Note that macvlan_dev are already RCU protected, as they
are embedded in a standard netdev (netdev_priv(ndev)).
https: //lore.kernel.org/netdev/695fb1e8.050a0220.1c677c.039f.GAE@google.com/T/#u |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: Discard Beacon frames to non-broadcast address
Beacon frames are required to be sent to the broadcast address, see IEEE
Std 802.11-2020, 11.1.3.1 ("The Address 1 field of the Beacon .. frame
shall be set to the broadcast address"). A unicast Beacon frame might be
used as a targeted attack to get one of the associated STAs to do
something (e.g., using CSA to move it to another channel). As such, it
is better have strict filtering for this on the received side and
discard all Beacon frames that are sent to an unexpected address.
This is even more important for cases where beacon protection is used.
The current implementation in mac80211 is correctly discarding unicast
Beacon frames if the Protected Frame bit in the Frame Control field is
set to 0. However, if that bit is set to 1, the logic used for checking
for configured BIGTK(s) does not actually work. If the driver does not
have logic for dropping unicast Beacon frames with Protected Frame bit
1, these frames would be accepted in mac80211 processing as valid Beacon
frames even though they are not protected. This would allow beacon
protection to be bypassed. While the logic for checking beacon
protection could be extended to cover this corner case, a more generic
check for discard all Beacon frames based on A1=unicast address covers
this without needing additional changes.
Address all these issues by dropping received Beacon frames if they are
sent to a non-broadcast address. |
| In the Linux kernel, the following vulnerability has been resolved:
tracing: Do not register unsupported perf events
Synthetic events currently do not have a function to register perf events.
This leads to calling the tracepoint register functions with a NULL
function pointer which triggers:
------------[ cut here ]------------
WARNING: kernel/tracepoint.c:175 at tracepoint_add_func+0x357/0x370, CPU#2: perf/2272
Modules linked in: kvm_intel kvm irqbypass
CPU: 2 UID: 0 PID: 2272 Comm: perf Not tainted 6.18.0-ftest-11964-ge022764176fc-dirty #323 PREEMPTLAZY
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
RIP: 0010:tracepoint_add_func+0x357/0x370
Code: 28 9c e8 4c 0b f5 ff eb 0f 4c 89 f7 48 c7 c6 80 4d 28 9c e8 ab 89 f4 ff 31 c0 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc <0f> 0b 49 c7 c6 ea ff ff ff e9 ee fe ff ff 0f 0b e9 f9 fe ff ff 0f
RSP: 0018:ffffabc0c44d3c40 EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffff9380aa9e4060 RCX: 0000000000000000
RDX: 000000000000000a RSI: ffffffff9e1d4a98 RDI: ffff937fcf5fd6c8
RBP: 0000000000000001 R08: 0000000000000007 R09: ffff937fcf5fc780
R10: 0000000000000003 R11: ffffffff9c193910 R12: 000000000000000a
R13: ffffffff9e1e5888 R14: 0000000000000000 R15: ffffabc0c44d3c78
FS: 00007f6202f5f340(0000) GS:ffff93819f00f000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d3162281a8 CR3: 0000000106a56003 CR4: 0000000000172ef0
Call Trace:
<TASK>
tracepoint_probe_register+0x5d/0x90
synth_event_reg+0x3c/0x60
perf_trace_event_init+0x204/0x340
perf_trace_init+0x85/0xd0
perf_tp_event_init+0x2e/0x50
perf_try_init_event+0x6f/0x230
? perf_event_alloc+0x4bb/0xdc0
perf_event_alloc+0x65a/0xdc0
__se_sys_perf_event_open+0x290/0x9f0
do_syscall_64+0x93/0x7b0
? entry_SYSCALL_64_after_hwframe+0x76/0x7e
? trace_hardirqs_off+0x53/0xc0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Instead, have the code return -ENODEV, which doesn't warn and has perf
error out with:
# perf record -e synthetic:futex_wait
Error:
The sys_perf_event_open() syscall returned with 19 (No such device) for event (synthetic:futex_wait).
"dmesg | grep -i perf" may provide additional information.
Ideally perf should support synthetic events, but for now just fix the
warning. The support can come later. |
| In the Linux kernel, the following vulnerability has been resolved:
parisc: Do not reprogram affinitiy on ASP chip
The ASP chip is a very old variant of the GSP chip and is used e.g. in
HP 730 workstations. When trying to reprogram the affinity it will crash
with a HPMC as the relevant registers don't seem to be at the usual
location. Let's avoid the crash by checking the sversion. Also note,
that reprogramming isn't necessary either, as the HP730 is a just a
single-CPU machine. |
| In the Linux kernel, the following vulnerability has been resolved:
SUNRPC: svcauth_gss: avoid NULL deref on zero length gss_token in gss_read_proxy_verf
A zero length gss_token results in pages == 0 and in_token->pages[0]
is NULL. The code unconditionally evaluates
page_address(in_token->pages[0]) for the initial memcpy, which can
dereference NULL even when the copy length is 0. Guard the first
memcpy so it only runs when length > 0. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: use global inline_xattr_slab instead of per-sb slab cache
As Hong Yun reported in mailing list:
loop7: detected capacity change from 0 to 131072
------------[ cut here ]------------
kmem_cache of name 'f2fs_xattr_entry-7:7' already exists
WARNING: CPU: 0 PID: 24426 at mm/slab_common.c:110 kmem_cache_sanity_check mm/slab_common.c:109 [inline]
WARNING: CPU: 0 PID: 24426 at mm/slab_common.c:110 __kmem_cache_create_args+0xa6/0x320 mm/slab_common.c:307
CPU: 0 UID: 0 PID: 24426 Comm: syz.7.1370 Not tainted 6.17.0-rc4 #1 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014
RIP: 0010:kmem_cache_sanity_check mm/slab_common.c:109 [inline]
RIP: 0010:__kmem_cache_create_args+0xa6/0x320 mm/slab_common.c:307
Call Trace:
__kmem_cache_create include/linux/slab.h:353 [inline]
f2fs_kmem_cache_create fs/f2fs/f2fs.h:2943 [inline]
f2fs_init_xattr_caches+0xa5/0xe0 fs/f2fs/xattr.c:843
f2fs_fill_super+0x1645/0x2620 fs/f2fs/super.c:4918
get_tree_bdev_flags+0x1fb/0x260 fs/super.c:1692
vfs_get_tree+0x43/0x140 fs/super.c:1815
do_new_mount+0x201/0x550 fs/namespace.c:3808
do_mount fs/namespace.c:4136 [inline]
__do_sys_mount fs/namespace.c:4347 [inline]
__se_sys_mount+0x298/0x2f0 fs/namespace.c:4324
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x8e/0x3a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x76/0x7e
The bug can be reproduced w/ below scripts:
- mount /dev/vdb /mnt1
- mount /dev/vdc /mnt2
- umount /mnt1
- mounnt /dev/vdb /mnt1
The reason is if we created two slab caches, named f2fs_xattr_entry-7:3
and f2fs_xattr_entry-7:7, and they have the same slab size. Actually,
slab system will only create one slab cache core structure which has
slab name of "f2fs_xattr_entry-7:3", and two slab caches share the same
structure and cache address.
So, if we destroy f2fs_xattr_entry-7:3 cache w/ cache address, it will
decrease reference count of slab cache, rather than release slab cache
entirely, since there is one more user has referenced the cache.
Then, if we try to create slab cache w/ name "f2fs_xattr_entry-7:3" again,
slab system will find that there is existed cache which has the same name
and trigger the warning.
Let's changes to use global inline_xattr_slab instead of per-sb slab cache
for fixing. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Fix VM hard lockup after prolonged inactivity with periodic HV timer
When advancing the target expiration for the guest's APIC timer in periodic
mode, set the expiration to "now" if the target expiration is in the past
(similar to what is done in update_target_expiration()). Blindly adding
the period to the previous target expiration can result in KVM generating
a practically unbounded number of hrtimer IRQs due to programming an
expired timer over and over. In extreme scenarios, e.g. if userspace
pauses/suspends a VM for an extended duration, this can even cause hard
lockups in the host.
Currently, the bug only affects Intel CPUs when using the hypervisor timer
(HV timer), a.k.a. the VMX preemption timer. Unlike the software timer,
a.k.a. hrtimer, which KVM keeps running even on exits to userspace, the
HV timer only runs while the guest is active. As a result, if the vCPU
does not run for an extended duration, there will be a huge gap between
the target expiration and the current time the vCPU resumes running.
Because the target expiration is incremented by only one period on each
timer expiration, this leads to a series of timer expirations occurring
rapidly after the vCPU/VM resumes.
More critically, when the vCPU first triggers a periodic HV timer
expiration after resuming, advancing the expiration by only one period
will result in a target expiration in the past. As a result, the delta
may be calculated as a negative value. When the delta is converted into
an absolute value (tscdeadline is an unsigned u64), the resulting value
can overflow what the HV timer is capable of programming. I.e. the large
value will exceed the VMX Preemption Timer's maximum bit width of
cpu_preemption_timer_multi + 32, and thus cause KVM to switch from the
HV timer to the software timer (hrtimers).
After switching to the software timer, periodic timer expiration callbacks
may be executed consecutively within a single clock interrupt handler,
because hrtimers honors KVM's request for an expiration in the past and
immediately re-invokes KVM's callback after reprogramming. And because
the interrupt handler runs with IRQs disabled, restarting KVM's hrtimer
over and over until the target expiration is advanced to "now" can result
in a hard lockup.
E.g. the following hard lockup was triggered in the host when running a
Windows VM (only relevant because it used the APIC timer in periodic mode)
after resuming the VM from a long suspend (in the host).
NMI watchdog: Watchdog detected hard LOCKUP on cpu 45
...
RIP: 0010:advance_periodic_target_expiration+0x4d/0x80 [kvm]
...
RSP: 0018:ff4f88f5d98d8ef0 EFLAGS: 00000046
RAX: fff0103f91be678e RBX: fff0103f91be678e RCX: 00843a7d9e127bcc
RDX: 0000000000000002 RSI: 0052ca4003697505 RDI: ff440d5bfbdbd500
RBP: ff440d5956f99200 R08: ff2ff2a42deb6a84 R09: 000000000002a6c0
R10: 0122d794016332b3 R11: 0000000000000000 R12: ff440db1af39cfc0
R13: ff440db1af39cfc0 R14: ffffffffc0d4a560 R15: ff440db1af39d0f8
FS: 00007f04a6ffd700(0000) GS:ff440db1af380000(0000) knlGS:000000e38a3b8000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000d5651feff8 CR3: 000000684e038002 CR4: 0000000000773ee0
PKRU: 55555554
Call Trace:
<IRQ>
apic_timer_fn+0x31/0x50 [kvm]
__hrtimer_run_queues+0x100/0x280
hrtimer_interrupt+0x100/0x210
? ttwu_do_wakeup+0x19/0x160
smp_apic_timer_interrupt+0x6a/0x130
apic_timer_interrupt+0xf/0x20
</IRQ>
Moreover, if the suspend duration of the virtual machine is not long enough
to trigger a hard lockup in this scenario, since commit 98c25ead5eda
("KVM: VMX: Move preemption timer <=> hrtimer dance to common x86"), KVM
will continue using the software timer until the guest reprograms the APIC
timer in some way. Since the periodic timer does not require frequent APIC
timer register programming, the guest may continue to use the software
timer in
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
scs: fix a wrong parameter in __scs_magic
__scs_magic() needs a 'void *' variable, but a 'struct task_struct *' is
given. 'task_scs(tsk)' is the starting address of the task's shadow call
stack, and '__scs_magic(task_scs(tsk))' is the end address of the task's
shadow call stack. Here should be '__scs_magic(task_scs(tsk))'.
The user-visible effect of this bug is that when CONFIG_DEBUG_STACK_USAGE
is enabled, the shadow call stack usage checking function
(scs_check_usage) would scan an incorrect memory range. This could lead
1. **Inaccurate stack usage reporting**: The function would calculate
wrong usage statistics for the shadow call stack, potentially showing
incorrect value in kmsg.
2. **Potential kernel crash**: If the value of __scs_magic(tsk)is
greater than that of __scs_magic(task_scs(tsk)), the for loop may
access unmapped memory, potentially causing a kernel panic. However,
this scenario is unlikely because task_struct is allocated via the slab
allocator (which typically returns lower addresses), while the shadow
call stack returned by task_scs(tsk) is allocated via vmalloc(which
typically returns higher addresses).
However, since this is purely a debugging feature
(CONFIG_DEBUG_STACK_USAGE), normal production systems should be not
unaffected. The bug only impacts developers and testers who are actively
debugging stack usage with this configuration enabled. |
| In the Linux kernel, the following vulnerability has been resolved:
ip6_gre: make ip6gre_header() robust
Over the years, syzbot found many ways to crash the kernel
in ip6gre_header() [1].
This involves team or bonding drivers ability to dynamically
change their dev->needed_headroom and/or dev->hard_header_len
In this particular crash mld_newpack() allocated an skb
with a too small reserve/headroom, and by the time mld_sendpack()
was called, syzbot managed to attach an ip6gre device.
[1]
skbuff: skb_under_panic: text:ffffffff8a1d69a8 len:136 put:40 head:ffff888059bc7000 data:ffff888059bc6fe8 tail:0x70 end:0x6c0 dev:team0
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:213 !
<TASK>
skb_under_panic net/core/skbuff.c:223 [inline]
skb_push+0xc3/0xe0 net/core/skbuff.c:2641
ip6gre_header+0xc8/0x790 net/ipv6/ip6_gre.c:1371
dev_hard_header include/linux/netdevice.h:3436 [inline]
neigh_connected_output+0x286/0x460 net/core/neighbour.c:1618
neigh_output include/net/neighbour.h:556 [inline]
ip6_finish_output2+0xfb3/0x1480 net/ipv6/ip6_output.c:136
__ip6_finish_output net/ipv6/ip6_output.c:-1 [inline]
ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:220
NF_HOOK_COND include/linux/netfilter.h:307 [inline]
ip6_output+0x340/0x550 net/ipv6/ip6_output.c:247
NF_HOOK+0x9e/0x380 include/linux/netfilter.h:318
mld_sendpack+0x8d4/0xe60 net/ipv6/mcast.c:1855
mld_send_cr net/ipv6/mcast.c:2154 [inline]
mld_ifc_work+0x83e/0xd60 net/ipv6/mcast.c:2693 |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/core: Check for the presence of LS_NLA_TYPE_DGID correctly
The netlink response for RDMA_NL_LS_OP_IP_RESOLVE should always have a
LS_NLA_TYPE_DGID attribute, it is invalid if it does not.
Use the nl parsing logic properly and call nla_parse_deprecated() to fill
the nlattrs array and then directly index that array to get the data for
the DGID. Just fail if it is NULL.
Remove the for loop searching for the nla, and squash the validation and
parsing into one function.
Fixes an uninitialized read from the stack triggered by userspace if it
does not provide the DGID to a kernel initiated RDMA_NL_LS_OP_IP_RESOLVE
query.
BUG: KMSAN: uninit-value in hex_byte_pack include/linux/hex.h:13 [inline]
BUG: KMSAN: uninit-value in ip6_string+0xef4/0x13a0 lib/vsprintf.c:1490
hex_byte_pack include/linux/hex.h:13 [inline]
ip6_string+0xef4/0x13a0 lib/vsprintf.c:1490
ip6_addr_string+0x18a/0x3e0 lib/vsprintf.c:1509
ip_addr_string+0x245/0xee0 lib/vsprintf.c:1633
pointer+0xc09/0x1bd0 lib/vsprintf.c:2542
vsnprintf+0xf8a/0x1bd0 lib/vsprintf.c:2930
vprintk_store+0x3ae/0x1530 kernel/printk/printk.c:2279
vprintk_emit+0x307/0xcd0 kernel/printk/printk.c:2426
vprintk_default+0x3f/0x50 kernel/printk/printk.c:2465
vprintk+0x36/0x50 kernel/printk/printk_safe.c:82
_printk+0x17e/0x1b0 kernel/printk/printk.c:2475
ib_nl_process_good_ip_rsep drivers/infiniband/core/addr.c:128 [inline]
ib_nl_handle_ip_res_resp+0x963/0x9d0 drivers/infiniband/core/addr.c:141
rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline]
rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
rdma_nl_rcv+0xefa/0x11c0 drivers/infiniband/core/netlink.c:259
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0xf04/0x12b0 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x333/0x3d0 net/socket.c:729
____sys_sendmsg+0x7e0/0xd80 net/socket.c:2617
___sys_sendmsg+0x271/0x3b0 net/socket.c:2671
__sys_sendmsg+0x1aa/0x300 net/socket.c:2703
__compat_sys_sendmsg net/compat.c:346 [inline]
__do_compat_sys_sendmsg net/compat.c:353 [inline]
__se_compat_sys_sendmsg net/compat.c:350 [inline]
__ia32_compat_sys_sendmsg+0xa4/0x100 net/compat.c:350
ia32_sys_call+0x3f6c/0x4310 arch/x86/include/generated/asm/syscalls_32.h:371
do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
__do_fast_syscall_32+0xb0/0x150 arch/x86/entry/syscall_32.c:306
do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:3 |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: BUG() in pskb_expand_head() as part of calipso_skbuff_setattr()
There exists a kernel oops caused by a BUG_ON(nhead < 0) at
net/core/skbuff.c:2232 in pskb_expand_head().
This bug is triggered as part of the calipso_skbuff_setattr()
routine when skb_cow() is passed headroom > INT_MAX
(i.e. (int)(skb_headroom(skb) + len_delta) < 0).
The root cause of the bug is due to an implicit integer cast in
__skb_cow(). The check (headroom > skb_headroom(skb)) is meant to ensure
that delta = headroom - skb_headroom(skb) is never negative, otherwise
we will trigger a BUG_ON in pskb_expand_head(). However, if
headroom > INT_MAX and delta <= -NET_SKB_PAD, the check passes, delta
becomes negative, and pskb_expand_head() is passed a negative value for
nhead.
Fix the trigger condition in calipso_skbuff_setattr(). Avoid passing
"negative" headroom sizes to skb_cow() within calipso_skbuff_setattr()
by only using skb_cow() to grow headroom.
PoC:
Using `netlabelctl` tool:
netlabelctl map del default
netlabelctl calipso add pass doi:7
netlabelctl map add default address:0::1/128 protocol:calipso,7
Then run the following PoC:
int fd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
// setup msghdr
int cmsg_size = 2;
int cmsg_len = 0x60;
struct msghdr msg;
struct sockaddr_in6 dest_addr;
struct cmsghdr * cmsg = (struct cmsghdr *) calloc(1,
sizeof(struct cmsghdr) + cmsg_len);
msg.msg_name = &dest_addr;
msg.msg_namelen = sizeof(dest_addr);
msg.msg_iov = NULL;
msg.msg_iovlen = 0;
msg.msg_control = cmsg;
msg.msg_controllen = cmsg_len;
msg.msg_flags = 0;
// setup sockaddr
dest_addr.sin6_family = AF_INET6;
dest_addr.sin6_port = htons(31337);
dest_addr.sin6_flowinfo = htonl(31337);
dest_addr.sin6_addr = in6addr_loopback;
dest_addr.sin6_scope_id = 31337;
// setup cmsghdr
cmsg->cmsg_len = cmsg_len;
cmsg->cmsg_level = IPPROTO_IPV6;
cmsg->cmsg_type = IPV6_HOPOPTS;
char * hop_hdr = (char *)cmsg + sizeof(struct cmsghdr);
hop_hdr[1] = 0x9; //set hop size - (0x9 + 1) * 8 = 80
sendmsg(fd, &msg, 0); |
| In the Linux kernel, the following vulnerability has been resolved:
tpm: Cap the number of PCR banks
tpm2_get_pcr_allocation() does not cap any upper limit for the number of
banks. Cap the limit to eight banks so that out of bounds values coming
from external I/O cause on only limited harm. |
| In the Linux kernel, the following vulnerability has been resolved:
functionfs: fix the open/removal races
ffs_epfile_open() can race with removal, ending up with file->private_data
pointing to freed object.
There is a total count of opened files on functionfs (both ep0 and
dynamic ones) and when it hits zero, dynamic files get removed.
Unfortunately, that removal can happen while another thread is
in ffs_epfile_open(), but has not incremented the count yet.
In that case open will succeed, leaving us with UAF on any subsequent
read() or write().
The root cause is that ffs->opened is misused; atomic_dec_and_test() vs.
atomic_add_return() is not a good idea, when object remains visible all
along.
To untangle that
* serialize openers on ffs->mutex (both for ep0 and for dynamic files)
* have dynamic ones use atomic_inc_not_zero() and fail if we had
zero ->opened; in that case the file we are opening is doomed.
* have the inodes of dynamic files marked on removal (from the
callback of simple_recursive_removal()) - clear ->i_private there.
* have open of dynamic ones verify they hadn't been already removed,
along with checking that state is FFS_ACTIVE. |
| In the Linux kernel, the following vulnerability has been resolved:
ipvs: fix ipv4 null-ptr-deref in route error path
The IPv4 code path in __ip_vs_get_out_rt() calls dst_link_failure()
without ensuring skb->dev is set, leading to a NULL pointer dereference
in fib_compute_spec_dst() when ipv4_link_failure() attempts to send
ICMP destination unreachable messages.
The issue emerged after commit ed0de45a1008 ("ipv4: recompile ip options
in ipv4_link_failure") started calling __ip_options_compile() from
ipv4_link_failure(). This code path eventually calls fib_compute_spec_dst()
which dereferences skb->dev. An attempt was made to fix the NULL skb->dev
dereference in commit 0113d9c9d1cc ("ipv4: fix null-deref in
ipv4_link_failure"), but it only addressed the immediate dev_net(skb->dev)
dereference by using a fallback device. The fix was incomplete because
fib_compute_spec_dst() later in the call chain still accesses skb->dev
directly, which remains NULL when IPVS calls dst_link_failure().
The crash occurs when:
1. IPVS processes a packet in NAT mode with a misconfigured destination
2. Route lookup fails in __ip_vs_get_out_rt() before establishing a route
3. The error path calls dst_link_failure(skb) with skb->dev == NULL
4. ipv4_link_failure() → ipv4_send_dest_unreach() →
__ip_options_compile() → fib_compute_spec_dst()
5. fib_compute_spec_dst() dereferences NULL skb->dev
Apply the same fix used for IPv6 in commit 326bf17ea5d4 ("ipvs: fix
ipv6 route unreach panic"): set skb->dev from skb_dst(skb)->dev before
calling dst_link_failure().
KASAN: null-ptr-deref in range [0x0000000000000328-0x000000000000032f]
CPU: 1 PID: 12732 Comm: syz.1.3469 Not tainted 6.6.114 #2
RIP: 0010:__in_dev_get_rcu include/linux/inetdevice.h:233
RIP: 0010:fib_compute_spec_dst+0x17a/0x9f0 net/ipv4/fib_frontend.c:285
Call Trace:
<TASK>
spec_dst_fill net/ipv4/ip_options.c:232
spec_dst_fill net/ipv4/ip_options.c:229
__ip_options_compile+0x13a1/0x17d0 net/ipv4/ip_options.c:330
ipv4_send_dest_unreach net/ipv4/route.c:1252
ipv4_link_failure+0x702/0xb80 net/ipv4/route.c:1265
dst_link_failure include/net/dst.h:437
__ip_vs_get_out_rt+0x15fd/0x19e0 net/netfilter/ipvs/ip_vs_xmit.c:412
ip_vs_nat_xmit+0x1d8/0xc80 net/netfilter/ipvs/ip_vs_xmit.c:764 |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: NFSv4 file creation neglects setting ACL
An NFSv4 client that sets an ACL with a named principal during file
creation retrieves the ACL afterwards, and finds that it is only a
default ACL (based on the mode bits) and not the ACL that was
requested during file creation. This violates RFC 8881 section
6.4.1.3: "the ACL attribute is set as given".
The issue occurs in nfsd_create_setattr(), which calls
nfsd_attrs_valid() to determine whether to call nfsd_setattr().
However, nfsd_attrs_valid() checks only for iattr changes and
security labels, but not POSIX ACLs. When only an ACL is present,
the function returns false, nfsd_setattr() is skipped, and the
POSIX ACL is never applied to the inode.
Subsequently, when the client retrieves the ACL, the server finds
no POSIX ACL on the inode and returns one generated from the file's
mode bits rather than returning the originally-specified ACL. |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix to avoid updating zero-sized extent in extent cache
As syzbot reported:
F2FS-fs (loop0): __update_extent_tree_range: extent len is zero, type: 0, extent [0, 0, 0], age [0, 0]
------------[ cut here ]------------
kernel BUG at fs/f2fs/extent_cache.c:678!
Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5336 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__update_extent_tree_range+0x13bc/0x1500 fs/f2fs/extent_cache.c:678
Call Trace:
<TASK>
f2fs_update_read_extent_cache_range+0x192/0x3e0 fs/f2fs/extent_cache.c:1085
f2fs_do_zero_range fs/f2fs/file.c:1657 [inline]
f2fs_zero_range+0x10c1/0x1580 fs/f2fs/file.c:1737
f2fs_fallocate+0x583/0x990 fs/f2fs/file.c:2030
vfs_fallocate+0x669/0x7e0 fs/open.c:342
ioctl_preallocate fs/ioctl.c:289 [inline]
file_ioctl+0x611/0x780 fs/ioctl.c:-1
do_vfs_ioctl+0xb33/0x1430 fs/ioctl.c:576
__do_sys_ioctl fs/ioctl.c:595 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:583
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: 0033:0x7f07bc58eec9
In error path of f2fs_zero_range(), it may add a zero-sized extent
into extent cache, it should be avoided. |
| In the Linux kernel, the following vulnerability has been resolved:
net: openvswitch: fix middle attribute validation in push_nsh() action
The push_nsh() action structure looks like this:
OVS_ACTION_ATTR_PUSH_NSH(OVS_KEY_ATTR_NSH(OVS_NSH_KEY_ATTR_BASE,...))
The outermost OVS_ACTION_ATTR_PUSH_NSH attribute is OK'ed by the
nla_for_each_nested() inside __ovs_nla_copy_actions(). The innermost
OVS_NSH_KEY_ATTR_BASE/MD1/MD2 are OK'ed by the nla_for_each_nested()
inside nsh_key_put_from_nlattr(). But nothing checks if the attribute
in the middle is OK. We don't even check that this attribute is the
OVS_KEY_ATTR_NSH. We just do a double unwrap with a pair of nla_data()
calls - first time directly while calling validate_push_nsh() and the
second time as part of the nla_for_each_nested() macro, which isn't
safe, potentially causing invalid memory access if the size of this
attribute is incorrect. The failure may not be noticed during
validation due to larger netlink buffer, but cause trouble later during
action execution where the buffer is allocated exactly to the size:
BUG: KASAN: slab-out-of-bounds in nsh_hdr_from_nlattr+0x1dd/0x6a0 [openvswitch]
Read of size 184 at addr ffff88816459a634 by task a.out/22624
CPU: 8 UID: 0 PID: 22624 6.18.0-rc7+ #115 PREEMPT(voluntary)
Call Trace:
<TASK>
dump_stack_lvl+0x51/0x70
print_address_description.constprop.0+0x2c/0x390
kasan_report+0xdd/0x110
kasan_check_range+0x35/0x1b0
__asan_memcpy+0x20/0x60
nsh_hdr_from_nlattr+0x1dd/0x6a0 [openvswitch]
push_nsh+0x82/0x120 [openvswitch]
do_execute_actions+0x1405/0x2840 [openvswitch]
ovs_execute_actions+0xd5/0x3b0 [openvswitch]
ovs_packet_cmd_execute+0x949/0xdb0 [openvswitch]
genl_family_rcv_msg_doit+0x1d6/0x2b0
genl_family_rcv_msg+0x336/0x580
genl_rcv_msg+0x9f/0x130
netlink_rcv_skb+0x11f/0x370
genl_rcv+0x24/0x40
netlink_unicast+0x73e/0xaa0
netlink_sendmsg+0x744/0xbf0
__sys_sendto+0x3d6/0x450
do_syscall_64+0x79/0x2c0
entry_SYSCALL_64_after_hwframe+0x76/0x7e
</TASK>
Let's add some checks that the attribute is properly sized and it's
the only one attribute inside the action. Technically, there is no
real reason for OVS_KEY_ATTR_NSH to be there, as we know that we're
pushing an NSH header already, it just creates extra nesting, but
that's how uAPI works today. So, keeping as it is. |
