| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
mpls: fix NULL deref in mpls_valid_fib_dump_req() on CONFIG_INET=n
On CONFIG_INET=n builds, mpls_valid_fib_dump_req() walks the parsed
attribute table itself instead of calling ip_valid_fib_dump_req(). The
RTA_OIF arm passes tb[RTA_OIF] to nla_get_u32() without checking it is
present, so an RTM_GETROUTE dump for AF_MPLS with strict checking and no
RTA_OIF hits a NULL dereference.
RTM_GETROUTE is RTNL_KIND_GET, which rtnetlink_rcv_msg() permits without
CAP_NET_ADMIN, so an unprivileged user can trigger it.
Oops: general protection fault, probably for non-canonical address
0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:mpls_valid_fib_dump_req (net/mpls/af_mpls.c:2189)
Call Trace:
mpls_dump_routes (net/mpls/af_mpls.c:2236)
netlink_dump (net/netlink/af_netlink.c:2331)
__netlink_dump_start (net/netlink/af_netlink.c:2446)
rtnetlink_rcv_msg (net/core/rtnetlink.c:7033)
netlink_rcv_skb (net/netlink/af_netlink.c:2556)
netlink_unicast (net/netlink/af_netlink.c:1345)
netlink_sendmsg (net/netlink/af_netlink.c:1900)
__sock_sendmsg (net/socket.c:790)
____sys_sendmsg (net/socket.c:2684)
___sys_sendmsg (net/socket.c:2738)
__sys_sendmsg (net/socket.c:2770)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Skip unset attributes, as ip_valid_fib_dump_req() does. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: reject free space cache with more entries than pages
When loading a v1 free space cache, __load_free_space_cache() takes
num_entries and num_bitmaps straight from the on-disk
btrfs_free_space_header. That header is stored in the tree_root under a key
with type 0, which the tree-checker has no case for, so neither count is
validated before the load trusts it.
The load loops num_entries times and maps the next page whenever the current
one runs out, going through io_ctl_check_crc() -> io_ctl_map_page(), which
does io_ctl->pages[io_ctl->index++]. But pages[] is allocated in
io_ctl_init() from the cache inode's i_size, not from num_entries:
num_pages = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE);
io_ctl->pages = kcalloc(num_pages, sizeof(struct page *), GFP_NOFS);
So if num_entries claims more records than the pages can hold, io_ctl->index
runs off the end of pages[]. The write side never hits this because
io_ctl_add_entry() and io_ctl_add_bitmap() both stop once
io_ctl->index >= io_ctl->num_pages; the read side just never had the same
check.
To trigger it, take a clean cache (num_entries = <N> here), set num_entries
in the header to 0x10000, and fix up the leaf checksum so it still passes
the tree-checker. The cache inode has i_size = 65536, so num_pages is 16 and
pages[] is a 16-pointer (kmalloc-128) array. The load now tries to read
65536 entries, io_ctl->index walks up to 16, and pages[16] is read past the
array:
BUG: KASAN: slab-out-of-bounds in io_ctl_check_crc (fs/btrfs/free-space-cache.c:420 fs/btrfs/free-space-cache.c:565)
Read of size 8 at addr ffff88800c833a80 by task kworker/u8:3/58
io_ctl_check_crc (fs/btrfs/free-space-cache.c:420 fs/btrfs/free-space-cache.c:565)
__load_free_space_cache (fs/btrfs/free-space-cache.c:655 fs/btrfs/free-space-cache.c:820)
load_free_space_cache (fs/btrfs/free-space-cache.c:1017)
caching_thread (fs/btrfs/block-group.c:880)
btrfs_work_helper (fs/btrfs/async-thread.c:312)
process_one_work
worker_thread
kthread
ret_from_fork
free-space-cache.c:420 is io_ctl_map_page(), inlined into io_ctl_check_crc()
at line 565, which is why that is the frame KASAN names. The out-of-bounds
slot is then treated as a struct page and handed to crc32c(), so the bad
read turns into a GP fault.
Add the missing check to io_ctl_check_crc(), which is where both the entry
loop and the bitmap loop end up. When num_entries is too large the load now
fails like any corrupt cache: __load_free_space_cache() drops it and rebuilds
the free space from the extent tree, so a valid cache is never rejected. |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: fix sk_dst_cache double-free in xfrm_user_policy()
xfrm_user_policy() clears the socket dst cache with __sk_dst_reset(),
i.e. the non-atomic __sk_dst_set(sk, NULL): it reads sk_dst_cache with
rcu_dereference_protected(), stores NULL and dst_release()s the old dst.
That is only safe if no other thread modifies sk_dst_cache concurrently.
For a connected UDP socket that does not hold: the transmit fast path
(udp_sendmsg -> sk_dst_check -> sk_dst_reset) resets the cache locklessly
with an atomic xchg(). A per-socket policy change racing a send can make
both sides observe the same old dst and each dst_release() it, dropping
the socket's single reference twice and freeing the xfrm_dst bundle while
it is still referenced:
BUG: KASAN: slab-use-after-free in dst_release
Write of size 4 at addr ffff88801897b6c0 by task exploit/155
Call Trace:
...
dst_release (... ./include/linux/rcuref.h:109)
xfrm_user_policy (./include/net/sock.h:2239 ./include/net/sock.h:2256 net/xfrm/xfrm_state.c:3053)
do_ip_setsockopt (net/ipv4/ip_sockglue.c:1347)
ip_setsockopt (net/ipv4/ip_sockglue.c:1417)
do_sock_setsockopt (net/socket.c:2368)
__sys_setsockopt (net/socket.c:2393)
__x64_sys_setsockopt (net/socket.c:2396)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Reachable by an unprivileged user via a user+network namespace.
Use the atomic sk_dst_reset() so the cache is cleared and released with a
single xchg(): whichever side wins releases the dst once, the other sees
NULL and does nothing. Behaviour is otherwise unchanged. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: p54: validate RX frame length in p54_rx_eeprom_readback()
p54_rx_eeprom_readback() copies the requested EEPROM slice out of a
device-supplied readback frame without checking that the skb actually holds
that many bytes. Commit da1b9a55ff11 ("wifi: p54: prevent buffer-overflow in
p54_rx_eeprom_readback()") closed the destination overflow by copying a
fixed priv->eeprom_slice_size (and rejecting a mismatched advertised len),
but the source side is still unbounded: nothing verifies the frame is long
enough to supply that many bytes.
A malicious USB device can send a short frame whose advertised len matches
priv->eeprom_slice_size while the payload is truncated. The equality check
passes and memcpy() reads past the end of the skb, leaking adjacent heap:
BUG: KASAN: slab-out-of-bounds in p54_rx (drivers/net/wireless/intersil/p54/txrx.c:507)
Read of size 1016 at addr ffff88800f077114 by task swapper/0/0
Call Trace:
<IRQ>
...
__asan_memcpy (mm/kasan/shadow.c:105)
p54_rx (drivers/net/wireless/intersil/p54/txrx.c:507)
p54u_rx_cb (drivers/net/wireless/intersil/p54/p54usb.c:163)
__usb_hcd_giveback_urb (drivers/usb/core/hcd.c:1657)
dummy_timer (drivers/usb/gadget/udc/dummy_hcd.c:2005)
...
</IRQ>
The buggy address belongs to the object at ffff88800f0770c0
which belongs to the cache skbuff_small_head of size 704
The buggy address is located 84 bytes inside of
allocated 704-byte region [ffff88800f0770c0, ffff88800f077380)
Check that the slice fits in the skb before copying. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: fix unsol_bcast_probe_resp double free on alloc failure
ieee80211_set_unsol_bcast_probe_resp() calls kfree_rcu() on the old
template before allocating the replacement. If the kzalloc() then fails,
it returns -ENOMEM while link->u.ap.unsol_bcast_probe_resp still points
at the object already queued for freeing. A later update or AP teardown
re-queues that same rcu_head; the second free is caught by KASAN when the
RCU sheaf is processed in softirq:
BUG: KASAN: double-free in rcu_free_sheaf (mm/slub.c:5850)
Free of addr ffff88800d06f300 by task exploit/145
...
__rcu_free_sheaf_prepare (mm/slub.c:2634 mm/slub.c:2940)
rcu_free_sheaf (mm/slub.c:5850)
rcu_core (kernel/rcu/tree.c:2617 kernel/rcu/tree.c:2869)
handle_softirqs (kernel/softirq.c:622)
The buggy address belongs to the cache kmalloc-128 of size 128
Queue the old object for kfree_rcu() only after the new one is published,
matching ieee80211_set_probe_resp() and ieee80211_set_s1g_short_beacon(). |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm6: clear dst.dev on error to avoid double netdev_put in xfrm6_fill_dst()
On the error path where in6_dev_get(dev) returns NULL, xfrm6_fill_dst()
releases the device reference with netdev_put() but leaves
xdst->u.dst.dev set. dst_destroy() later calls netdev_put(dst->dev)
again, so the same net_device reference is released twice, underflowing
its refcount (ref_tracker WARNING + "unregister_netdevice: waiting for
<dev> to become free").
Clear xdst->u.dst.dev after the netdev_put(), the same way the XFRM
device-offload paths xfrm_dev_state_add() and xfrm_dev_policy_add() in
net/xfrm/xfrm_device.c NULL ->dev when releasing the reference on error.
ref_tracker: reference already released.
ref_tracker: allocated in:
xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:86)
...
udpv6_sendmsg (net/ipv6/udp.c:1696)
...
ref_tracker: freed in:
xfrm6_fill_dst (net/ipv6/xfrm6_policy.c:90)
...
WARNING: lib/ref_tracker.c:322 at ref_tracker_free+0x58b/0x780
dst_destroy (net/core/dst.c:115)
rcu_core
handle_softirqs
... |
| In the Linux kernel, the following vulnerability has been resolved:
f2fs: compress: fix to avoid use-after-free on dic
Call trace:
__memcpy+0x128/0x250
f2fs_read_multi_pages+0x940/0xf7c
f2fs_mpage_readpages+0x5a8/0x624
f2fs_readahead+0x5c/0x110
page_cache_ra_unbounded+0x1b8/0x590
do_sync_mmap_readahead+0x1dc/0x2e4
filemap_fault+0x254/0xa8c
f2fs_filemap_fault+0x2c/0x104
__do_fault+0x7c/0x238
do_handle_mm_fault+0x11bc/0x2d14
do_mem_abort+0x3a8/0x1004
el0_da+0x3c/0xa0
el0t_64_sync_handler+0xc4/0xec
el0t_64_sync+0x1b4/0x1b8
In f2fs_read_multi_pages(), once f2fs_decompress_cluster() was called if
we hit cached page in compress_inode's cache, dic may be released, it needs
break the loop rather than continuing it, in order to avoid accessing
invalid dic pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
ibmvnic: fix race between xmit and reset
There is a race between reset and the transmit paths that can lead to
ibmvnic_xmit() accessing an scrq after it has been freed in the reset
path. It can result in a crash like:
Kernel attempted to read user page (0) - exploit attempt? (uid: 0)
BUG: Kernel NULL pointer dereference on read at 0x00000000
Faulting instruction address: 0xc0080000016189f8
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP [c0080000016189f8] ibmvnic_xmit+0x60/0xb60 [ibmvnic]
LR [c000000000c0046c] dev_hard_start_xmit+0x11c/0x280
Call Trace:
[c008000001618f08] ibmvnic_xmit+0x570/0xb60 [ibmvnic] (unreliable)
[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280
[c000000000c9cfcc] sch_direct_xmit+0xec/0x330
[c000000000bfe640] __dev_xmit_skb+0x3a0/0x9d0
[c000000000c00ad4] __dev_queue_xmit+0x394/0x730
[c008000002db813c] __bond_start_xmit+0x254/0x450 [bonding]
[c008000002db8378] bond_start_xmit+0x40/0xc0 [bonding]
[c000000000c0046c] dev_hard_start_xmit+0x11c/0x280
[c000000000c00ca4] __dev_queue_xmit+0x564/0x730
[c000000000cf97e0] neigh_hh_output+0xd0/0x180
[c000000000cfa69c] ip_finish_output2+0x31c/0x5c0
[c000000000cfd244] __ip_queue_xmit+0x194/0x4f0
[c000000000d2a3c4] __tcp_transmit_skb+0x434/0x9b0
[c000000000d2d1e0] __tcp_retransmit_skb+0x1d0/0x6a0
[c000000000d2d984] tcp_retransmit_skb+0x34/0x130
[c000000000d310e8] tcp_retransmit_timer+0x388/0x6d0
[c000000000d315ec] tcp_write_timer_handler+0x1bc/0x330
[c000000000d317bc] tcp_write_timer+0x5c/0x200
[c000000000243270] call_timer_fn+0x50/0x1c0
[c000000000243704] __run_timers.part.0+0x324/0x460
[c000000000243894] run_timer_softirq+0x54/0xa0
[c000000000ea713c] __do_softirq+0x15c/0x3e0
[c000000000166258] __irq_exit_rcu+0x158/0x190
[c000000000166420] irq_exit+0x20/0x40
[c00000000002853c] timer_interrupt+0x14c/0x2b0
[c000000000009a00] decrementer_common_virt+0x210/0x220
--- interrupt: 900 at plpar_hcall_norets_notrace+0x18/0x2c
The immediate cause of the crash is the access of tx_scrq in the following
snippet during a reset, where the tx_scrq can be either NULL or an address
that will soon be invalid:
ibmvnic_xmit()
{
...
tx_scrq = adapter->tx_scrq[queue_num];
txq = netdev_get_tx_queue(netdev, queue_num);
ind_bufp = &tx_scrq->ind_buf;
if (test_bit(0, &adapter->resetting)) {
...
}
But beyond that, the call to ibmvnic_xmit() itself is not safe during a
reset and the reset path attempts to avoid this by stopping the queue in
ibmvnic_cleanup(). However just after the queue was stopped, an in-flight
ibmvnic_complete_tx() could have restarted the queue even as the reset is
progressing.
Since the queue was restarted we could get a call to ibmvnic_xmit() which
can then access the bad tx_scrq (or other fields).
We cannot however simply have ibmvnic_complete_tx() check the ->resetting
bit and skip starting the queue. This can race at the "back-end" of a good
reset which just restarted the queue but has not cleared the ->resetting
bit yet. If we skip restarting the queue due to ->resetting being true,
the queue would remain stopped indefinitely potentially leading to transmit
timeouts.
IOW ->resetting is too broad for this purpose. Instead use a new flag
that indicates whether or not the queues are active. Only the open/
reset paths control when the queues are active. ibmvnic_complete_tx()
and others wake up the queue only if the queue is marked active.
So we will have:
A. reset/open thread in ibmvnic_cleanup() and __ibmvnic_open()
->resetting = true
->tx_queues_active = false
disable tx queues
...
->tx_queues_active = true
start tx queues
B. Tx interrupt in ibmvnic_complete_tx():
if (->tx_queues_active)
netif_wake_subqueue();
To ensure that ->tx_queues_active and state of the queues are consistent,
we need a lock which:
- must also be taken in the interrupt path (ibmvnic_complete_tx())
- shared across the multiple
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
vdpa/mlx5: add validation for VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET command
When control vq receives a VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET command
request from the driver, presently there is no validation against the
number of queue pairs to configure, or even if multiqueue had been
negotiated or not is unverified. This may lead to kernel panic due to
uninitialized resource for the queues were there any bogus request
sent down by untrusted driver. Tie up the loose ends there. |
| In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix out-of-bounds read in rtw_get_ie() parser
The Information Element (IE) parser rtw_get_ie() trusted the length
byte of each IE without validating that the IE body (len bytes after
the 2-byte header) fits inside the remaining frame buffer. A malformed
frame can advertise an IE length larger than the available data, causing
the parser to increment its pointer beyond the buffer end. This results
in out-of-bounds reads or, depending on the pattern, an infinite loop.
Fix by validating that (offset + 2 + len) does not exceed the limit
before accepting the IE or advancing to the next element.
This prevents OOB reads and ensures the parser terminates safely on
malformed frames. |
| In the Linux kernel, the following vulnerability has been resolved:
nvme: fix admin request_queue lifetime
The namespaces can access the controller's admin request_queue, and
stale references on the namespaces may exist after tearing down the
controller. Ensure the admin request_queue is active by moving the
controller's 'put' to after all controller references have been released
to ensure no one is can access the request_queue. This fixes a reported
use-after-free bug:
BUG: KASAN: slab-use-after-free in blk_queue_enter+0x41c/0x4a0
Read of size 8 at addr ffff88c0a53819f8 by task nvme/3287
CPU: 67 UID: 0 PID: 3287 Comm: nvme Tainted: G E 6.13.2-ga1582f1a031e #15
Tainted: [E]=UNSIGNED_MODULE
Hardware name: Jabil /EGS 2S MB1, BIOS 1.00 06/18/2025
Call Trace:
<TASK>
dump_stack_lvl+0x4f/0x60
print_report+0xc4/0x620
? _raw_spin_lock_irqsave+0x70/0xb0
? _raw_read_unlock_irqrestore+0x30/0x30
? blk_queue_enter+0x41c/0x4a0
kasan_report+0xab/0xe0
? blk_queue_enter+0x41c/0x4a0
blk_queue_enter+0x41c/0x4a0
? __irq_work_queue_local+0x75/0x1d0
? blk_queue_start_drain+0x70/0x70
? irq_work_queue+0x18/0x20
? vprintk_emit.part.0+0x1cc/0x350
? wake_up_klogd_work_func+0x60/0x60
blk_mq_alloc_request+0x2b7/0x6b0
? __blk_mq_alloc_requests+0x1060/0x1060
? __switch_to+0x5b7/0x1060
nvme_submit_user_cmd+0xa9/0x330
nvme_user_cmd.isra.0+0x240/0x3f0
? force_sigsegv+0xe0/0xe0
? nvme_user_cmd64+0x400/0x400
? vfs_fileattr_set+0x9b0/0x9b0
? cgroup_update_frozen_flag+0x24/0x1c0
? cgroup_leave_frozen+0x204/0x330
? nvme_ioctl+0x7c/0x2c0
blkdev_ioctl+0x1a8/0x4d0
? blkdev_common_ioctl+0x1930/0x1930
? fdget+0x54/0x380
__x64_sys_ioctl+0x129/0x190
do_syscall_64+0x5b/0x160
entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f765f703b0b
Code: ff ff ff 85 c0 79 9b 49 c7 c4 ff ff ff ff 5b 5d 4c 89 e0 41 5c c3 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d dd 52 0f 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe2cefe808 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffe2cefe860 RCX: 00007f765f703b0b
RDX: 00007ffe2cefe860 RSI: 00000000c0484e41 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000000
R10: 00007f765f611d50 R11: 0000000000000202 R12: 0000000000000003
R13: 00000000c0484e41 R14: 0000000000000001 R15: 00007ffe2cefea60
</TASK> |
| In the Linux kernel, the following vulnerability has been resolved:
proc: protect ptrace_may_access() with exec_update_lock (part 1)
Fix the easy cases where procfs currently calls ptrace_may_access() without
exec_update_lock protection, where the fix is to simply add the extra lock
or use mm_access():
- do_task_stat(): grab exec_update_lock
- proc_pid_wchan(): grab exec_update_lock
- proc_map_files_lookup(): use mm_access() instead of get_task_mm()
- proc_map_files_readdir(): use mm_access() instead of get_task_mm()
- proc_ns_get_link(): grab exec_update_lock
- proc_ns_readlink(): grab exec_update_lock |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: asymmetric_keys - fix OOB read in pefile_digest_pe_contents
pefile_digest_pe_contents() computes the trailing-data hash length as
pelen - (hashed_bytes + certs_size). A crafted PE can make the addition
exceed pelen, causing the unsigned subtraction to underflow to ~4 GiB.
This is passed to crypto_shash_update() which reads out of bounds and
panics on unmapped vmalloc guard pages.
BUG: unable to handle page fault for address: ffffc900038d8000
Oops: Oops: 0000 [#1] SMP KASAN NOPTI
RIP: 0010:sha256_blocks_generic (lib/crypto/sha256.c:152)
Call Trace:
<TASK>
__sha256_update (lib/crypto/sha256.c:208)
crypto_sha256_update (crypto/sha256.c:142)
verify_pefile_signature (crypto/asymmetric_keys/verify_pefile.c:436)
kexec_kernel_verify_pe_sig (kernel/kexec_file.c:151)
__do_sys_kexec_file_load (kernel/kexec_file.c:406)
do_syscall_64 (arch/x86/entry/syscall_64.c:94)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
</TASK>
Kernel panic - not syncing: Fatal exception
Validate that the addition does not overflow and the result does not
exceed pelen before the subtraction. Return -ELIBBAD on failure. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: uvc: hold opts->lock across XU walks in uvc_function_bind
uvc_function_bind() walks &opts->extension_units twice without holding
opts->lock:
- directly, for the iExtension string-descriptor fixup loop;
- indirectly, four times via uvc_copy_descriptors() (once per speed),
where the helper iterates uvc->desc.extension_units (which aliases
&opts->extension_units) to size and emit XU descriptors.
The configfs side (uvcg_extension_make / uvcg_extension_drop, in
drivers/usb/gadget/function/uvc_configfs.c) takes opts->lock around its
list_add_tail / list_del operations. A privileged userspace process
that holds the configfs subtree open and writes the gadget UDC name
to bind the function while concurrently rmdir()'ing an extensions
subdir can race uvcg_extension_drop() against the bind-time list walks
and dereference a freed struct uvcg_extension.
Hold opts->lock from the start of the XU string-descriptor fixup
through the last uvc_copy_descriptors() call, releasing on the
descriptor-error path via a new error_unlock label that drops the
lock before falling through to the existing error label. This
matches the locking discipline of the configfs callbacks and removes
the only remaining unsynchronised reader of the XU list during bind.
Reachability: only privileged processes that can mount configfs and
write to gadget UDC files can trigger the race, so this is a
correctness fix rather than a security boundary. |
| In the Linux kernel, the following vulnerability has been resolved:
power: reset: linkstation-poweroff: fix use-after-free in the linkstation_poweroff_init()
Move of_node_put(dn) after the of_match_node() call, which still needs
the node pointer. The node reference is correctly released after use. |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: Unconditionally recompute CR8 intercept on PPR update
The TPR_THRESHOLD field in the VMCS is used by VMX to induce VM exits
when the guest's virtual TPR falls under the specified threshold,
allowing KVM to inject previously masked interrupts.
KVM handles these VM exits in handle_tpr_below_threshold().
Commit eb90f3417a0c ("KVM: vmx: speed up TPR below threshold vmexits")
optimized this function by calling apic_update_ppr() instead of raising
KVM_REQ_EVENT. apic_update_ppr() then raises KVM_REQ_EVENT if there is
a pending, deliverable interrupt.
However, if there are no new interrupts pending, apic_update_ppr() does
not issue the request. Thus, kvm_lapic_update_cr8_intercept() and
vmx_update_cr8_intercept() are not called before VM entry, which results
in a high, stale TPR_THRESHOLD. This is problematic due to the following
sentence in 28.2.1.1 "VM-Execution Control Fields" in the SDM:
The following check is performed if the “use TPR shadow” VM-execution
control is 1 and the “virtualize APIC accesses” and “virtual-interrupt
delivery” VM-execution controls are both 0: the value of bits 3:0 of
the TPR threshold VM-execution control field should not be greater
than the value of bits 7:4 of VTPR.
This error condition is typically not observed when KVM runs on a bare
metal system because modern processors support APICv, which enables
virtual-interrupt delivery, and which KVM uses when possible. This
causes the processor to no longer generate TPR-below-threshold exits
and to no longer check TPR_THRESHOLD on entry. However, when running
on older platforms, or under nested virtualization on a hypervisor that
does not support virtual-interrupt delivery and enforces this check
(like Hyper-V) this can cause a VM entry failure with hardware error
0x7, as seen in [1].
Call kvm_lapic_update_cr8_intercept() if apic_update_ppr() does not
find a deliverable interrupt (and thus does not raise KVM_REQ_EVENT).
Remove calls to kvm_lapic_update_cr8_intercept() on paths that end up in
apic_update_ppr(), as they now become redundant. This ensures that any
path that updates the guest's PPR also figures out if KVM needs to wait
for a TPR change (using TPR_THRESHOLD on VMX or CR8 intercepts on SVM). |
| In the Linux kernel, the following vulnerability has been resolved:
drm/hyperv: validate resolution_count and fix WIN8 fallback
A SYNTHVID_RESOLUTION_RESPONSE with resolution_count > 64 walks past
the supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT] array in the
parse loop. Bound resolution_count against the array size, folded
into the existing zero-check.
When the WIN10 resolution probe fails, the caller in
hyperv_connect_vsp() left hv->screen_*_max / preferred_* unpopulated,
which sets mode_config.max_width / max_height to 0 and makes
drm_internal_framebuffer_create() reject every userspace framebuffer
with -EINVAL. The pre-WIN10 branch had the same gap for
preferred_width / preferred_height. Use a single post-probe fallback
guarded by screen_width_max == 0 so both paths converge on the WIN8
defaults. |
| In the Linux kernel, the following vulnerability has been resolved:
block: recompute nr_integrity_segments in blk_insert_cloned_request
blk_insert_cloned_request() already recomputes nr_phys_segments
against the bottom queue, because "the queue settings related to
segment counting may differ from the original queue." The exact same
reasoning applies to integrity segments: a stacked driver's underlying
queue can have tighter virt_boundary_mask, seg_boundary_mask, or
max_segment_size than the top queue, in which case
blk_rq_count_integrity_sg() against the bottom queue produces a
different count than the cached rq->nr_integrity_segments inherited
from the source request by blk_rq_prep_clone().
When the cached count is lower than the bottom queue's actual count,
blk_rq_map_integrity_sg() trips
BUG_ON(segments > rq->nr_integrity_segments);
on dispatch. The same families of stacked setups that motivated the
existing nr_phys_segments recompute -- dm-multipath fanning out to
nvme-rdma in particular -- can produce this.
Mirror the nr_phys_segments handling: when the request carries
integrity, recompute nr_integrity_segments against the bottom queue
and reject the request if it exceeds the bottom queue's
max_integrity_segments. blk_rq_count_integrity_sg() and
queue_max_integrity_segments() are both already available via
<linux/blk-integrity.h>, which blk-mq.c includes.
This closes a latent gap in the stacking contract and brings the
integrity-segment accounting in line with the existing
phys-segment accounting. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/damon/sysfs-schemes: delete tried region in regions_rmdirs()
DAMON sysfs maintains the DAMOS tried region directory objects via a
linked list. When the user requests refresh of the directories, DAMON
sysfs removes all the region directories first, and then generate updated
regions directory on the empty space. The removal function
(damon_sysfs_scheme_regions_rm_dirs()) only puts the kobj objects.
Deletion of the container region object from the linked list is done
inside the kobj release callback function.
If somehow the callback invocation is delayed, the list will contain
regions list that gonna be freed. If the updated region directories
creation is started in this situation, the list can be corrupted and
use-after-free can happen.
Because the kobj objects are managed by only DAMON sysfs, the issue cannot
happen in normal situation. But, such delays can be made on kernels that
built with CONFIG_DEBUG_KOBJECT_RELEASE. On the kernel, the issue can
indeed be reproduced like below.
# damo start --damos_action stat
# cd /sys/kernel/mm/damon/admin/kdamonds/0/
# for i in {1..10}; do echo update_schemes_tried_regions > state; done
# dmesg | grep underflow
[ 89.296152] refcount_t: underflow; use-after-free.
Fix the issue by removing the region object from the list when
decrementing the reference count.
Also update damos_sysfs_populate_region_dir() to add the region object to
the list only after the kobject_init_and_add() is success, so that fail of
kobject_init_and_add() is not leaving the deallocated object on the list.
The issue was discovered [1] by Sashiko. |
| In the Linux kernel, the following vulnerability has been resolved:
usb: gadget: net2280: Fix double free in probe error path
usb_initialize_gadget() installs gadget_release() as the release
callback for the embedded gadget device. The struct net2280 instance is
therefore released through gadget_release() when the gadget device's last
reference is dropped.
The probe error path calls net2280_remove(), which tears down the
partially initialized device and drops the gadget reference with
usb_put_gadget(). Calling kfree(dev) afterwards can free the same object
again.
Drop the explicit kfree() and let the gadget device release callback
handle the final free. This issue was found by a static analysis tool
I am developing. |
