| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: hide VRAM sysfs attributes on GPUs without VRAM
Otherwise accessing them can cause a crash. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix NULL pointer dereference in VRAM logic for APU devices
Previously, APU platforms (and other scenarios with uninitialized VRAM managers)
triggered a NULL pointer dereference in `ttm_resource_manager_usage()`. The root
cause is not that the `struct ttm_resource_manager *man` pointer itself is NULL,
but that `man->bdev` (the backing device pointer within the manager) remains
uninitialized (NULL) on APUs—since APUs lack dedicated VRAM and do not fully
set up VRAM manager structures. When `ttm_resource_manager_usage()` attempts to
acquire `man->bdev->lru_lock`, it dereferences the NULL `man->bdev`, leading to
a kernel OOPS.
1. **amdgpu_cs.c**: Extend the existing bandwidth control check in
`amdgpu_cs_get_threshold_for_moves()` to include a check for
`ttm_resource_manager_used()`. If the manager is not used (uninitialized
`bdev`), return 0 for migration thresholds immediately—skipping VRAM-specific
logic that would trigger the NULL dereference.
2. **amdgpu_kms.c**: Update the `AMDGPU_INFO_VRAM_USAGE` ioctl and memory info
reporting to use a conditional: if the manager is used, return the real VRAM
usage; otherwise, return 0. This avoids accessing `man->bdev` when it is
NULL.
3. **amdgpu_virt.c**: Modify the vf2pf (virtual function to physical function)
data write path. Use `ttm_resource_manager_used()` to check validity: if the
manager is usable, calculate `fb_usage` from VRAM usage; otherwise, set
`fb_usage` to 0 (APUs have no discrete framebuffer to report).
This approach is more robust than APU-specific checks because it:
- Works for all scenarios where the VRAM manager is uninitialized (not just APUs),
- Aligns with TTM's design by using its native helper function,
- Preserves correct behavior for discrete GPUs (which have fully initialized
`man->bdev` and pass the `ttm_resource_manager_used()` check).
v4: use ttm_resource_manager_used(&adev->mman.vram_mgr.manager) instead of checking the adev->gmc.is_app_apu flag (Christian) |
| In the Linux kernel, the following vulnerability has been resolved:
exfat: fix improper check of dentry.stream.valid_size
We found an infinite loop bug in the exFAT file system that can lead to a
Denial-of-Service (DoS) condition. When a dentry in an exFAT filesystem is
malformed, the following system calls — SYS_openat, SYS_ftruncate, and
SYS_pwrite64 — can cause the kernel to hang.
Root cause analysis shows that the size validation code in exfat_find()
does not check whether dentry.stream.valid_size is negative. As a result,
the system calls mentioned above can succeed and eventually trigger the DoS
issue.
This patch adds a check for negative dentry.stream.valid_size to prevent
this vulnerability. |
| In the Linux kernel, the following vulnerability has been resolved:
smb/server: fix possible memory leak in smb2_read()
Memory leak occurs when ksmbd_vfs_read() fails.
Fix this by adding the missing kvfree(). |
| In the Linux kernel, the following vulnerability has been resolved:
smb/server: fix possible refcount leak in smb2_sess_setup()
Reference count of ksmbd_session will leak when session need reconnect.
Fix this by adding the missing ksmbd_user_session_put(). |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: MGMT: cancel mesh send timer when hdev removed
mesh_send_done timer is not canceled when hdev is removed, which causes
crash if the timer triggers after hdev is gone.
Cancel the timer when MGMT removes the hdev, like other MGMT timers.
Should fix the BUG: sporadically seen by BlueZ test bot
(in "Mesh - Send cancel - 1" test).
Log:
------
BUG: KASAN: slab-use-after-free in run_timer_softirq+0x76b/0x7d0
...
Freed by task 36:
kasan_save_stack+0x24/0x50
kasan_save_track+0x14/0x30
__kasan_save_free_info+0x3a/0x60
__kasan_slab_free+0x43/0x70
kfree+0x103/0x500
device_release+0x9a/0x210
kobject_put+0x100/0x1e0
vhci_release+0x18b/0x240
------ |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: btusb: reorder cleanup in btusb_disconnect to avoid UAF
There is a KASAN: slab-use-after-free read in btusb_disconnect().
Calling "usb_driver_release_interface(&btusb_driver, data->intf)" will
free the btusb data associated with the interface. The same data is
then used later in the function, hence the UAF.
Fix by moving the accesses to btusb data to before the data is free'd. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: 6lowpan: reset link-local header on ipv6 recv path
Bluetooth 6lowpan.c netdev has header_ops, so it must set link-local
header for RX skb, otherwise things crash, eg. with AF_PACKET SOCK_RAW
Add missing skb_reset_mac_header() for uncompressed ipv6 RX path.
For the compressed one, it is done in lowpan_header_decompress().
Log: (BlueZ 6lowpan-tester Client Recv Raw - Success)
------
kernel BUG at net/core/skbuff.c:212!
Call Trace:
<IRQ>
...
packet_rcv (net/packet/af_packet.c:2152)
...
<TASK>
__local_bh_enable_ip (kernel/softirq.c:407)
netif_rx (net/core/dev.c:5648)
chan_recv_cb (net/bluetooth/6lowpan.c:294 net/bluetooth/6lowpan.c:359)
------ |
| In the Linux kernel, the following vulnerability has been resolved:
sctp: prevent possible shift-out-of-bounds in sctp_transport_update_rto
syzbot reported a possible shift-out-of-bounds [1]
Blamed commit added rto_alpha_max and rto_beta_max set to 1000.
It is unclear if some sctp users are setting very large rto_alpha
and/or rto_beta.
In order to prevent user regression, perform the test at run time.
Also add READ_ONCE() annotations as sysctl values can change under us.
[1]
UBSAN: shift-out-of-bounds in net/sctp/transport.c:509:41
shift exponent 64 is too large for 32-bit type 'unsigned int'
CPU: 0 UID: 0 PID: 16704 Comm: syz.2.2320 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x16c/0x1f0 lib/dump_stack.c:120
ubsan_epilogue lib/ubsan.c:233 [inline]
__ubsan_handle_shift_out_of_bounds+0x27f/0x420 lib/ubsan.c:494
sctp_transport_update_rto.cold+0x1c/0x34b net/sctp/transport.c:509
sctp_check_transmitted+0x11c4/0x1c30 net/sctp/outqueue.c:1502
sctp_outq_sack+0x4ef/0x1b20 net/sctp/outqueue.c:1338
sctp_cmd_process_sack net/sctp/sm_sideeffect.c:840 [inline]
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1372 [inline] |
| In the Linux kernel, the following vulnerability has been resolved:
tipc: Fix use-after-free in tipc_mon_reinit_self().
syzbot reported use-after-free of tipc_net(net)->monitors[]
in tipc_mon_reinit_self(). [0]
The array is protected by RTNL, but tipc_mon_reinit_self()
iterates over it without RTNL.
tipc_mon_reinit_self() is called from tipc_net_finalize(),
which is always under RTNL except for tipc_net_finalize_work().
Let's hold RTNL in tipc_net_finalize_work().
[0]:
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
Read of size 1 at addr ffff88805eae1030 by task kworker/0:7/5989
CPU: 0 UID: 0 PID: 5989 Comm: kworker/0:7 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Workqueue: events tipc_net_finalize_work
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 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
__kasan_check_byte+0x2a/0x40 mm/kasan/common.c:568
kasan_check_byte include/linux/kasan.h:399 [inline]
lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5842
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
rtlock_slowlock kernel/locking/rtmutex.c:1894 [inline]
rwbase_rtmutex_lock_state kernel/locking/spinlock_rt.c:160 [inline]
rwbase_write_lock+0xd3/0x7e0 kernel/locking/rwbase_rt.c:244
rt_write_lock+0x76/0x110 kernel/locking/spinlock_rt.c:243
write_lock_bh include/linux/rwlock_rt.h:99 [inline]
tipc_mon_reinit_self+0x79/0x430 net/tipc/monitor.c:718
tipc_net_finalize+0x115/0x190 net/tipc/net.c:140
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x439/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 6089:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:388 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:405
kasan_kmalloc include/linux/kasan.h:260 [inline]
__kmalloc_cache_noprof+0x1a8/0x320 mm/slub.c:4407
kmalloc_noprof include/linux/slab.h:905 [inline]
kzalloc_noprof include/linux/slab.h:1039 [inline]
tipc_mon_create+0xc3/0x4d0 net/tipc/monitor.c:657
tipc_enable_bearer net/tipc/bearer.c:357 [inline]
__tipc_nl_bearer_enable+0xe16/0x13f0 net/tipc/bearer.c:1047
__tipc_nl_compat_doit net/tipc/netlink_compat.c:371 [inline]
tipc_nl_compat_doit+0x3bc/0x5f0 net/tipc/netlink_compat.c:393
tipc_nl_compat_handle net/tipc/netlink_compat.c:-1 [inline]
tipc_nl_compat_recv+0x83c/0xbe0 net/tipc/netlink_compat.c:1321
genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115
genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210
netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552
genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
netlink_unicast+0x846/0xa10 net/netlink/af_netlink.c:1346
netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896
sock_sendmsg_nosec net/socket.c:714 [inline]
__sock_sendmsg+0x21c/0x270 net/socket.c:729
____sys_sendmsg+0x508/0x820 net/socket.c:2614
___sys_sendmsg+0x21f/0x2a0 net/socket.c:2668
__sys_sendmsg net/socket.c:2700 [inline]
__do_sys_sendmsg net/socket.c:2705 [inline]
__se_sys_sendmsg net/socket.c:2703 [inline]
__x64_sys_sendmsg+0x1a1/0x260 net/socket.c:2703
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net: sched: act_connmark: initialize struct tc_ife to fix kernel leak
In tcf_connmark_dump(), the variable 'opt' was partially initialized using a
designatied initializer. While the padding bytes are reamined
uninitialized. nla_put() copies the entire structure into a
netlink message, these uninitialized bytes leaked to userspace.
Initialize the structure with memset before assigning its fields
to ensure all members and padding are cleared prior to beign copied. |
| In the Linux kernel, the following vulnerability has been resolved:
net: sched: act_ife: initialize struct tc_ife to fix KMSAN kernel-infoleak
Fix a KMSAN kernel-infoleak detected by the syzbot .
[net?] KMSAN: kernel-infoleak in __skb_datagram_iter
In tcf_ife_dump(), the variable 'opt' was partially initialized using a
designatied initializer. While the padding bytes are reamined
uninitialized. nla_put() copies the entire structure into a
netlink message, these uninitialized bytes leaked to userspace.
Initialize the structure with memset before assigning its fields
to ensure all members and padding are cleared prior to beign copied.
This change silences the KMSAN report and prevents potential information
leaks from the kernel memory.
This fix has been tested and validated by syzbot. This patch closes the
bug reported at the following syzkaller link and ensures no infoleak. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vmwgfx: Validate command header size against SVGA_CMD_MAX_DATASIZE
This data originates from userspace and is used in buffer offset
calculations which could potentially overflow causing an out-of-bounds
access. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/panthor: Flush shmem writes before mapping buffers CPU-uncached
The shmem layer zeroes out the new pages using cached mappings, and if
we don't CPU-flush we might leave dirty cachelines behind, leading to
potential data leaks and/or asynchronous buffer corruption when dirty
cachelines are evicted. |
| In the Linux kernel, the following vulnerability has been resolved:
ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd
In snd_usb_create_streams(), for UAC version 3 devices, the Interface
Association Descriptor (IAD) is retrieved via usb_ifnum_to_if(). If this
call fails, a fallback routine attempts to obtain the IAD from the next
interface and sets a BADD profile. However, snd_usb_mixer_controls_badd()
assumes that the IAD retrieved from usb_ifnum_to_if() is always valid,
without performing a NULL check. This can lead to a NULL pointer
dereference when usb_ifnum_to_if() fails to find the interface descriptor.
This patch adds a NULL pointer check after calling usb_ifnum_to_if() in
snd_usb_mixer_controls_badd() to prevent the dereference.
This issue was discovered by syzkaller, which triggered the bug by sending
a crafted USB device descriptor. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: guest_memfd: Remove bindings on memslot deletion when gmem is dying
When unbinding a memslot from a guest_memfd instance, remove the bindings
even if the guest_memfd file is dying, i.e. even if its file refcount has
gone to zero. If the memslot is freed before the file is fully released,
nullifying the memslot side of the binding in kvm_gmem_release() will
write to freed memory, as detected by syzbot+KASAN:
==================================================================
BUG: KASAN: slab-use-after-free in kvm_gmem_release+0x176/0x440 virt/kvm/guest_memfd.c:353
Write of size 8 at addr ffff88807befa508 by task syz.0.17/6022
CPU: 0 UID: 0 PID: 6022 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x189/0x250 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
kvm_gmem_release+0x176/0x440 virt/kvm/guest_memfd.c:353
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbeeff8efc9
</TASK>
Allocated by task 6023:
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
poison_kmalloc_redzone mm/kasan/common.c:397 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414
kasan_kmalloc include/linux/kasan.h:262 [inline]
__kmalloc_cache_noprof+0x3e2/0x700 mm/slub.c:5758
kmalloc_noprof include/linux/slab.h:957 [inline]
kzalloc_noprof include/linux/slab.h:1094 [inline]
kvm_set_memory_region+0x747/0xb90 virt/kvm/kvm_main.c:2104
kvm_vm_ioctl_set_memory_region+0x6f/0xd0 virt/kvm/kvm_main.c:2154
kvm_vm_ioctl+0x957/0xc60 virt/kvm/kvm_main.c:5201
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 6023:
kasan_save_stack mm/kasan/common.c:56 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:252 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
kasan_slab_free include/linux/kasan.h:234 [inline]
slab_free_hook mm/slub.c:2533 [inline]
slab_free mm/slub.c:6622 [inline]
kfree+0x19a/0x6d0 mm/slub.c:6829
kvm_set_memory_region+0x9c4/0xb90 virt/kvm/kvm_main.c:2130
kvm_vm_ioctl_set_memory_region+0x6f/0xd0 virt/kvm/kvm_main.c:2154
kvm_vm_ioctl+0x957/0xc60 virt/kvm/kvm_main.c:5201
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:597 [inline]
__se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Deliberately don't acquire filemap invalid lock when the file is dying as
the lifecycle of f_mapping is outside the purview of KVM. Dereferencing
the mapping is *probably* fine, but there's no need to invalidate anything
as memslot deletion is responsible for zapping SPTEs, and the only code
that can access the dying file is kvm_gmem_release(), whose core code is
mutual
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
NFSD: free copynotify stateid in nfs4_free_ol_stateid()
Typically copynotify stateid is freed either when parent's stateid
is being close/freed or in nfsd4_laundromat if the stateid hasn't
been used in a lease period.
However, in case when the server got an OPEN (which created
a parent stateid), followed by a COPY_NOTIFY using that stateid,
followed by a client reboot. New client instance while doing
CREATE_SESSION would force expire previous state of this client.
It leads to the open state being freed thru release_openowner->
nfs4_free_ol_stateid() and it finds that it still has copynotify
stateid associated with it. We currently print a warning and is
triggerred
WARNING: CPU: 1 PID: 8858 at fs/nfsd/nfs4state.c:1550 nfs4_free_ol_stateid+0xb0/0x100 [nfsd]
This patch, instead, frees the associated copynotify stateid here.
If the parent stateid is freed (without freeing the copynotify
stateids associated with it), it leads to the list corruption
when laundromat ends up freeing the copynotify state later.
[ 1626.839430] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP
[ 1626.842828] Modules linked in: nfnetlink_queue nfnetlink_log bluetooth cfg80211 rpcrdma rdma_cm iw_cm ib_cm ib_core nfsd nfs_acl lockd grace nfs_localio ext4 crc16 mbcache jbd2 overlay uinput snd_seq_dummy snd_hrtimer qrtr rfkill vfat fat uvcvideo snd_hda_codec_generic videobuf2_vmalloc videobuf2_memops snd_hda_intel uvc snd_intel_dspcfg videobuf2_v4l2 videobuf2_common snd_hda_codec snd_hda_core videodev snd_hwdep snd_seq mc snd_seq_device snd_pcm snd_timer snd soundcore sg loop auth_rpcgss vsock_loopback vmw_vsock_virtio_transport_common vmw_vsock_vmci_transport vmw_vmci vsock xfs 8021q garp stp llc mrp nvme ghash_ce e1000e nvme_core sr_mod nvme_keyring nvme_auth cdrom vmwgfx drm_ttm_helper ttm sunrpc dm_mirror dm_region_hash dm_log iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi fuse dm_multipath dm_mod nfnetlink
[ 1626.855594] CPU: 2 UID: 0 PID: 199 Comm: kworker/u24:33 Kdump: loaded Tainted: G B W 6.17.0-rc7+ #22 PREEMPT(voluntary)
[ 1626.857075] Tainted: [B]=BAD_PAGE, [W]=WARN
[ 1626.857573] Hardware name: VMware, Inc. VMware20,1/VBSA, BIOS VMW201.00V.24006586.BA64.2406042154 06/04/2024
[ 1626.858724] Workqueue: nfsd4 laundromat_main [nfsd]
[ 1626.859304] pstate: 61400005 (nZCv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
[ 1626.860010] pc : __list_del_entry_valid_or_report+0x148/0x200
[ 1626.860601] lr : __list_del_entry_valid_or_report+0x148/0x200
[ 1626.861182] sp : ffff8000881d7a40
[ 1626.861521] x29: ffff8000881d7a40 x28: 0000000000000018 x27: ffff0000c2a98200
[ 1626.862260] x26: 0000000000000600 x25: 0000000000000000 x24: ffff8000881d7b20
[ 1626.862986] x23: ffff0000c2a981e8 x22: 1fffe00012410e7d x21: ffff0000920873e8
[ 1626.863701] x20: ffff0000920873e8 x19: ffff000086f22998 x18: 0000000000000000
[ 1626.864421] x17: 20747562202c3839 x16: 3932326636383030 x15: 3030666666662065
[ 1626.865092] x14: 6220646c756f6873 x13: 0000000000000001 x12: ffff60004fd9e4a3
[ 1626.865713] x11: 1fffe0004fd9e4a2 x10: ffff60004fd9e4a2 x9 : dfff800000000000
[ 1626.866320] x8 : 00009fffb0261b5e x7 : ffff00027ecf2513 x6 : 0000000000000001
[ 1626.866938] x5 : ffff00027ecf2510 x4 : ffff60004fd9e4a3 x3 : 0000000000000000
[ 1626.867553] x2 : 0000000000000000 x1 : ffff000096069640 x0 : 000000000000006d
[ 1626.868167] Call trace:
[ 1626.868382] __list_del_entry_valid_or_report+0x148/0x200 (P)
[ 1626.868876] _free_cpntf_state_locked+0xd0/0x268 [nfsd]
[ 1626.869368] nfs4_laundromat+0x6f8/0x1058 [nfsd]
[ 1626.869813] laundromat_main+0x24/0x60 [nfsd]
[ 1626.870231] process_one_work+0x584/0x1050
[ 1626.870595] worker_thread+0x4c4/0xc60
[ 1626.870893] kthread+0x2f8/0x398
[ 1626.871146] ret_from_fork+0x10/0x20
[ 1626.871422] Code: aa1303e1 aa1403e3 910e8000 97bc55d7 (d4210000)
[ 1626.871892] SMP: stopping secondary CPUs |
| In the Linux kernel, the following vulnerability has been resolved:
mm/secretmem: fix use-after-free race in fault handler
When a page fault occurs in a secret memory file created with
`memfd_secret(2)`, the kernel will allocate a new folio for it, mark the
underlying page as not-present in the direct map, and add it to the file
mapping.
If two tasks cause a fault in the same page concurrently, both could end
up allocating a folio and removing the page from the direct map, but only
one would succeed in adding the folio to the file mapping. The task that
failed undoes the effects of its attempt by (a) freeing the folio again
and (b) putting the page back into the direct map. However, by doing
these two operations in this order, the page becomes available to the
allocator again before it is placed back in the direct mapping.
If another task attempts to allocate the page between (a) and (b), and the
kernel tries to access it via the direct map, it would result in a
supervisor not-present page fault.
Fix the ordering to restore the direct map before the folio is freed. |
| In the Linux kernel, the following vulnerability has been resolved:
fs/proc: fix uaf in proc_readdir_de()
Pde is erased from subdir rbtree through rb_erase(), but not set the node
to EMPTY, which may result in uaf access. We should use RB_CLEAR_NODE()
set the erased node to EMPTY, then pde_subdir_next() will return NULL to
avoid uaf access.
We found an uaf issue while using stress-ng testing, need to run testcase
getdent and tun in the same time. The steps of the issue is as follows:
1) use getdent to traverse dir /proc/pid/net/dev_snmp6/, and current
pde is tun3;
2) in the [time windows] unregister netdevice tun3 and tun2, and erase
them from rbtree. erase tun3 first, and then erase tun2. the
pde(tun2) will be released to slab;
3) continue to getdent process, then pde_subdir_next() will return
pde(tun2) which is released, it will case uaf access.
CPU 0 | CPU 1
-------------------------------------------------------------------------
traverse dir /proc/pid/net/dev_snmp6/ | unregister_netdevice(tun->dev) //tun3 tun2
sys_getdents64() |
iterate_dir() |
proc_readdir() |
proc_readdir_de() | snmp6_unregister_dev()
pde_get(de); | proc_remove()
read_unlock(&proc_subdir_lock); | remove_proc_subtree()
| write_lock(&proc_subdir_lock);
[time window] | rb_erase(&root->subdir_node, &parent->subdir);
| write_unlock(&proc_subdir_lock);
read_lock(&proc_subdir_lock); |
next = pde_subdir_next(de); |
pde_put(de); |
de = next; //UAF |
rbtree of dev_snmp6
|
pde(tun3)
/ \
NULL pde(tun2) |
| In the Linux kernel, the following vulnerability has been resolved:
mm, swap: fix potential UAF issue for VMA readahead
Since commit 78524b05f1a3 ("mm, swap: avoid redundant swap device
pinning"), the common helper for allocating and preparing a folio in the
swap cache layer no longer tries to get a swap device reference
internally, because all callers of __read_swap_cache_async are already
holding a swap entry reference. The repeated swap device pinning isn't
needed on the same swap device.
Caller of VMA readahead is also holding a reference to the target entry's
swap device, but VMA readahead walks the page table, so it might encounter
swap entries from other devices, and call __read_swap_cache_async on
another device without holding a reference to it.
So it is possible to cause a UAF when swapoff of device A raced with
swapin on device B, and VMA readahead tries to read swap entries from
device A. It's not easy to trigger, but in theory, it could cause real
issues.
Make VMA readahead try to get the device reference first if the swap
device is a different one from the target entry. |