| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_api: Always acquire rtnl_lock when destroying locked classifiers
Another challenge with unlocked filters.
There is a short window in tc_new_tfilter where a tcf_proto can be found
and briefly referenced by a totally unrelated, unlocked classifier's request
and cause a race.
Feng created a poc which created this race with two threads, one creating a
u32 filter and other a flower filter in the same chain/prio:
1. Both threads enter tc_new_tfilter, both find the chain empty, both
drop filter_chain_lock
2. u32 finishes tcf_proto_create("u32") first, calls
tcf_chain_tp_insert_unique() -> inserts u32_tp into the chain
3. flower finishes tcf_proto_create("flower") later, calls
tcf_chain_tp_insert_unique() -> tcf_chain_tp_find() now sees u32_tp
already there, takes a reference on it, destroys flower's own tp_new
and returns u32_tp to the caller.
Flower then hits the kind mismatch check (because it requested for kind
"flower" but tp->ops->kind is "u32") and goes through the errout path
which calls tcf_proto_put() on u32_tp. If the u32 thread has already
gone through its own errout (its change() call failed on the PoC's empty
options) and dropped its create and insert refs, flower's put is the
last one and drops u32_tp's refcnt to zero.
At this point tp->ops->destroy() runs in a context that never took
rtnl_lock. When that happens, it might cause a UAF like the following
(illustrated by the PoC):
[ +0.000710] BUG: KASAN: slab-use-after-free in u32_init (net/sched/cls_u32.c:393)
[ +0.000281] Read of size 8 at addr ffff888120022f00 by task poc_feng_xue/524
Call Trace:
u32_init (net/sched/cls_u32.c:393)
tc_new_tfilter (net/sched/cls_api.c:2378)
Allocated by task 526:
u32_init (net/sched/cls_u32.c:378)
tc_new_tfilter (net/sched/cls_api.c:2378)
Freed by task 522:
kfree
u32_destroy (net/sched/cls_u32.c:662)
tcf_proto_destroy (net/sched/cls_api.c:446)
tcf_proto_put (net/sched/cls_api.c:459)
tc_new_tfilter (net/sched/cls_api.c:2459)
Fix this by having tcf_proto_destroy() take rtnl_lock around
tp->ops->destroy() for locked classifiers whenever rtnl is not held.
To explain why I used a temp variable "not_lockless" I'd like to point to a
semi-related note on rtnl_held vs TCF_PROTO_OPS_DOIT_UNLOCKED (adding here
for future cleanup if deemed necessary):
The rtnl_held parameter and the TCF_PROTO_OPS_DOIT_UNLOCKED flag are
redundant sources of truth for whether rtnl_lock is held. Among the nine
classifier destroy(..rtnl_held..) callbacks, only flower consults the
rtnl_held parameter which it propagates to tc_setup_cb_destroy()
and tc_setup_cb_call(). The other eight (u32, flow, bpf, cgroup, route, basic,
fw, mall) ignore it entirely;-> those that call tc_setup_cb_destroy()
(u32, bpf, mall) hardcode true always instead of forwarding the parameter.
A future cleanup should remove the rtnl_held parameter from the destroy callback
signature entirely and have callers rely solely on their knowledge whether
they are running in an unlocked context. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_flow_table: drop existing skb dst before skb_dst_set_noref()
Incoming skbs passing through netfilter flowtable offload hooks (or XFRM
offload path) might already carry a ref-counted dst_entry assigned during
earlier RX or routing steps.
Calling skb_dst_set_noref() when skb already holds a ref-counted dst
overwrites skb->_skb_refdst, leaking the previous dst_entry reference
count and triggering a DEBUG_NET_WARN_ON_ONCE assertion in
skb_dst_check_unset():
WARNING: at skb_dst_check_unset include/linux/skbuff.h:1170
WARNING: at skb_dst_set_noref include/linux/skbuff.h:1234
WARNING: at nf_flow_offload_ip_hook+0xf6c/0x2b60 net/netfilter/nf_flow_table_ip.c:864
Drop any existing dst_entry reference with skb_dst_drop(skb) before
setting the non-referenced flowtable destination. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/ism: Fix UAF of sba and ieq during ism_dev_exit()
A ism interrupt handler can be active in parallel with ism_dev_exit(),
accessing freed data structures.
No new interrupts will be generated after unregister_ieq(). Drain ongoing
interrupt handlers by free_irq(), before freeing ism data structures. |
| In the Linux kernel, the following vulnerability has been resolved:
watchdog: at91sam9_wdt: prevent timer rearm during teardown
at91_ping() rearms the watchdog timer from its callback. timer_delete()
neither waits for a running callback nor prevents it from rearming the
timer, so probe failure or driver removal can leave the timer accessing the
devm-allocated at91wdt after it has been freed.
Use timer_shutdown_sync() on both teardown paths. It waits for a running
callback and rejects any attempt by the callback to rearm the timer. |
| In the Linux kernel, the following vulnerability has been resolved:
net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp()
The commit 4f61f133f354 ("net: tap: NULL pointer derefence in
dev_parse_header_protocol when skb->dev is null") fixed a crash in
tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb().
This is required because virtio_net_hdr_to_skb() may invoke
dev_parse_header_protocol(), which dereferences skb->dev. Without the
assignment, a NULL pointer dereference can occur.
However, tap_get_user_xdp() still parses the virtio-net header before
assigning skb->dev. When the vhost TX path passes an XDP buffer containing
a GSO virtio-net header but the protocol is set to zero on purpose,
tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev
is still NULL, resulting in a crash.
Fix this by looking up the tap device and assigning skb->dev before calling
tun_vnet_hdr_to_skb(), matching the ordering already used in
tap_get_user(). Preserve the existing RCU read-side critical section across
dev_queue_xmit(). |
| In the Linux kernel, the following vulnerability has been resolved:
mm/vmalloc: acquire init_mm lock on huge vmap to avoid ptdump UAF
Patch series "mm: fix UAF caused by race between ptdump and vmap pgtable
freeing", v6.
Kernel page table walkers fall into two broad categories - those ranges
where no exclusion is required via walk_kernel_page_table_range_lockless()
and those where exclusion is required via walk_kernel_page_table_range()
or walk_page_range_debug().
The former category is used only by arm64 arch code operating on ranges it
both wholly owns and does not concurrently write.
The latter category consists of kernel page table walkers operating on
ranges that are wholly owned (but which need exclusion against concurrent
writers).
The lock used for exclusion is the mmap lock, and for kernel ranges this
is the mmap lock on init_mm.
ptdump is a special case being both the only user of
walk_page_range_debug(), and the only case in which it walks ranges it
does not own.
This presents a problem, as page tables may be freed under ptdump. And
indeed there is a use-after-free bug in the kernel as a result, which this
series addresses.
vmap promotes page tables to huge leaf entries where possible, freeing the
lower page table when it does. It does this with no meaningful locks held
against concurrent ptdump walks.
As a result, use-after-free can currently occur. This series addresses
the issue by having the vmap huge promotion logic acquire the mmap read
lock while both setting the huge page table entry and freeing the prior
leaf page table.
The ptdump code already acquires the mmap write lock, so by doing so we
ensure that the ptdump walker only ever observes either the huge page
table entry or the existing page table entry, and nothing is freed
underneath it.
A mitigation for this issue was already applied for arm64 in commit
fa93b45fd397 ("arm64: Enable vmalloc-huge with ptdump"), which this series
has to deal with carefully.
This mitigation resolves the issue by acquiring the mmap read lock on
init_mm on vmap page table free if a ptdump is in progress.
However the fix in this series would cause a deadlock if we were to simply
apply it for arm64 without also reverting the change.
This is because vmap may acquire the read lock before ptdump attempts to
acquire the write lock, which then gets queued, and rwsem starvation rules
mean that the (unacknowledged) nested mmap read lock in the arm64 code
would also block, meaning the original read lock is never released and
thus deadlock.
This series works around this by #ifndef CONFIG_ARM64'ing the mmap read
lock in vmap logic, then partially reverting commit fa93b45fd397 ("arm64:
Enable vmalloc-huge with ptdump"), keeping the enablement of huge vmap
support, and removing the ifdeffery with the partial revert patch.
There are related issues that are also addressed in this series:
* x86 page attribute logic, specifically Change Page Attributes (CPA),
implements a feature whereby huge ranges can be collapsed into huge leaf
entries. This can similarly cause a UAF when done in parallel with a
ptdump walk, so similarly acquire the init_mm mmap lock to avoid this.
* The CPA logic allows concurrent page table manipulation and CPA
collapse, meaning the former risks accessing a page table the latter
frees. Fix this by acquiring mmap write lock on init_mm across the
whole CPA collapse operation and read lock on the page table
manipulation.
* x86 and arm64 permit walks of non-kernel mm's (both allowing efi mm
walks, and in x86's case arbitrary mm's), so we ensure kernel mappings
remain stable by locking the init_mm as well as the mm being walked.
The ordering of patches is established for both strict dependencies (the
arm64 partial revert in particular has to be done after the vmap changes)
and logical ones (the non-kernel mm fix only makes sense once the vmap/CPA
fixes are in place).
This patch (of 3):
Currently there is a nasty ra
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
tls: rx: restore msg_iter before TLS 1.3 optimistic retry
tls_decrypt_sg() advances msg->msg_iter when it maps user pages for
the optimistic TLS 1.3 zero-copy path. If the decrypted record turns
out not to be unpadded application data, tls_decrypt_sw() retries into
a kernel skb, but leaves the iterator advanced.
The subsequent copy from the skb then writes decrypted bytes again at
a later point in the caller iovecs while recvmsg() reports only the
post-retry length. A TLS peer can trigger this after the receiver
enables TLS_RX_EXPECT_NO_PAD.
Revert the iterator by the number of bytes consumed by the optimistic
mapping before retrying without zero-copy.
Add a selftest which sends a TLS 1.3 control record with
TLS_RX_EXPECT_NO_PAD enabled and verifies that recvmsg() does not
overwrite later iovecs beyond the returned length. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/page_table_check: skip special zero mappings
page_table_check_set() and page_table_check_clear() account mappings based
on PageAnon(). Shared zero-page PTEs and huge zero PMDs are special
mappings, but page_table_check can still account them as file-backed
pages.
An unprivileged process can populate enough zero mappings to overflow
file_map_count and hit the existing BUG_ON(). The PTE path can do this
with the shared zero page, and the PMD path can do the same with huge zero
mappings.
Skip special zero mappings in the user page-table accounting paths. Keep
the PTE-side pte_special() check, and identify huge zero PMDs from the
mapped folio instead of pmd_special(). That covers architectures where
pmd_special() is a no-op without adding huge_zero_pfn checks to the
generic counter helpers. |
| In the Linux kernel, the following vulnerability has been resolved:
mm/ptdump: always stabilise against page table freeing using init_mm
Previous commits have established the invariant that kernel page table
freeing is performed while an mmap read lock on init_mm is held, which
fixes races between ptdump and kernel page table freeing over init_mm.
However, x86 and arm64 can perform a ptdump over an mm other than init_mm
via ptdump_walk_pgd() and since kernel memory ranges are shared across
non-kernel mm's, this means that the race still exists for these cases.
Fix this by acquiring a nested mmap write lock for init_mm in
ptdump_walk_pgd().
This is safe as we take this after mmap write locking the mm, and nothing
acquires the init_mm lock first before locking an arbitrary mm, so no
deadlock is possible.
Also update walk_page_range_debug() to assert that init_mm is write
locked, add a comment explaining why and remove some redundant code, and
eliminate the unnecessary and confusing invocation of
walk_kernel_page_table_range().
We can safely remove the non-NULL check for walk.mm, as the mmap lock
asserts would NULL pointer deref if it was (and of course no callers do
this).
The first point at which ptdump can race kernel page table freeing is
commit b6bdb7517c3d ("mm/vmalloc: add interfaces to free unmapped page
table"), so we target this in the Fixes tag. |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: skip global block reserve accounting for rescue mounts
[BUG]
Mounting with rescue=ibadroots after corrupting the block group tree
root triggers a NULL pointer dereference:
BUG: kernel NULL pointer dereference, address: 0000000000000100
RIP: 0010:btrfs_update_global_block_rsv+0x9d/0x1c0 [btrfs]
Call Trace:
fill_dummy_bgs+0xd4/0x120 [btrfs]
open_ctree+0xc6e/0x1ca0 [btrfs]
btrfs_get_tree+0x50d/0xa40 [btrfs]
The same crash occurs with a corrupted raid stripe tree root, via
btrfs_read_block_groups() instead of fill_dummy_bgs().
[CAUSE]
With rescue=ibadroots, btrfs_read_roots() allows the mount to continue
when either root cannot be read, leaving the corresponding root pointer
NULL while its on-disk feature bit remains set.
btrfs_update_global_block_rsv() then dereferences the missing root based
on the feature bit alone.
[FIX]
Rescue mounts are fully read-only and cannot start transactions, so the
global reserve is never consumed. Under btrfs_is_full_ro(), mark the
reserve as full and return before performing the accounting.
And since we need to check if the fs is mount fully RO, export
fs_is_full_ro() as btrfs_is_full_ro(), and move it to fs.h.
[ Squash the fs_is_full_ro() export commit into this one. ] |
| In the Linux kernel, the following vulnerability has been resolved:
net/sched: cls_u32: validate offshift to prevent shift-out-of-bounds
u32_change() copies the user-provided tc_u32_sel.offshift (unsigned char,
0-255) into the kernel knode object without bounds validation. When a
packet later hits u32_classify() with TC_U32_VAROFFSET set, it evaluates
`ntohs(offmask & *data) >> offshift` where the left operand is a 16-bit
value promoted to a 32-bit int. Any offshift >= 32 is undefined behavior
per C11 6.5.7p3, triggerable by an unprivileged user via user/network
namespaces.
UBSAN: shift-out-of-bounds in net/sched/cls_u32.c:236:43
shift exponent 32 is too large for 32-bit type int
Fix this by rejecting offshift >= 16 during filter creation in
u32_change(). |
| In the Linux kernel, the following vulnerability has been resolved:
net: udp_tunnel: fix memory leak in udp_tunnel_nic_unregister()
syzbot reported a memory leak [1] in the UDP tunnel NIC offload code.
When device registration fails (e.g. in register_netdevice()), netdev core
unwinds by sending a single NETDEV_UNREGISTER notification. If work was queued
during NETDEV_REGISTER (utn->work_pending is set), udp_tunnel_nic_unregister()
returns early:
if (utn->work_pending)
return;
Because failed registrations do not enter netdev_wait_allrefs_any(), no
subsequent NETDEV_UNREGISTER rebroadcast will ever occur. As a result, the
struct udp_tunnel_nic allocated in udp_tunnel_nic_alloc() is leaked
permanently.
Fix this by removing the early return. Instead, synchronously cancel any
pending work with cancel_delayed_work_sync() before freeing @utn.
To be able to call cancel_delayed_work_sync() while holding RTNL (the work also
needs RTNL), switch udp_tunnel_nic_device_sync_work() to rtnl_trylock(). If RTNL
is contended, requeue the work with a 1 jiffy delay (via queue_delayed_work())
to prevent high CPU contention while waiting for RTNL lock.
The utn->work_pending bookkeeping is no longer needed and is removed, as
the workqueue core already tracks the pending/running state of the work.
[1]
BUG: memory leak
unreferenced object 0xffff888127d5f840 (size 96):
comm "syz-executor", pid 5806, jiffies 4294942188
backtrace (crc 99fdb6c8):
__kmalloc_noprof+0x3bf/0x550
udp_tunnel_nic_alloc net/ipv4/udp_tunnel_nic.c:756 [inline]
udp_tunnel_nic_register net/ipv4/udp_tunnel_nic.c:833 [inline]
udp_tunnel_nic_netdevice_event+0x804/0xab0 net/ipv4/udp_tunnel_nic.c:931
notifier_call_chain+0x59/0x160 kernel/notifier.c:85
call_netdevice_notifiers_info+0x7d/0xb0 net/core/dev.c:2250
register_netdevice+0xc10/0xeb0 net/core/dev.c:11478 |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: ISO: hold sk properly in iso_conn_ready
sk deref in iso_conn_ready must be done either under conn->lock, or
holding a refcount, to avoid concurrent close. conn->sk is currently
accessed without either:
[Task 1] [Task 2]
iso_sock_release
iso_conn_ready
sk = conn->sk
lock_sock(sk)
conn->sk = NULL
lock_sock(sk)
release_sock(sk)
iso_sock_kill(sk)
UAF on sk deref
Fix possible UAF by holding sk refcount in iso_conn_ready(). Also
recheck after lock_sock that the socket is still valid. Adjust locking
so conn->sk is cleared only under lock_sock. |
| In the Linux kernel, the following vulnerability has been resolved:
octeontx2-af: Block VFs from clobbering special CGX PKIND state
PF and VF NIX LFs that share a CGX LMAC reuse the same hardware PKIND
programming. When HiGig2 or EDSA parsing is enabled, a VF NIX LF alloc must
not reset the LMAC RX PKIND or default TX parse config over the PF setup.
Add cgx_get_pkind() and rvu_cgx_is_pkind_config_permitted() so VFs skip
cgx_set_pkind(), rvu_npc_set_pkind(), and NIX_AF_LFX_TX_PARSE_CFG updates
when the LMAC is using NPC_RX_HIGIG_PKIND or NPC_RX_EDSA_PKIND. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/zcrypt: Close speculative mem read possibility
The domain value is extracted from a given CCA or EP11 ioctl struct
when a CPRB is about to be sent. Thus this is a user controlled value.
Under some special conditions (custom device node used, administrative
load) this value is used as an array index after bounds checking, but
without speculation barrier.
Add the missing array_index_nospec() call to prevent speculative
execution where this domain value is used. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/vmwgfx: reject DX_BIND_QUERY without a DX context
vmw_cmd_dx_bind_query() unconditionally dereferences
sw_context->dx_ctx_node->ctx. Userspace can trigger a NULL pointer
dereference from any render-node fd by submitting an execbuf with
dx_context_handle == SVGA3D_INVALID_ID and a SVGA_3D_CMD_DX_BIND_QUERY
opcode in the command stream: dx_ctx_node is left NULL and the kernel
oopses on the assignment. The same NULL is then re-read in
vmw_resources_reserve() via vmw_context_get_dx_query_mob().
All sibling DX handlers fail-close on a missing dx_ctx_node using
VMW_GET_CTX_NODE(). Use the same pattern here, returning -EINVAL up
front before any relocation state is published. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: fix integer overflow in radeon_align_pitch()
radeon_align_pitch() has the same kind of overflow issue as the old
amdgpu helper: both the alignment round-up add and the final
'aligned * cpp' calculation can overflow signed int.
If that wraps, radeon_mode_dumb_create() can end up returning an
invalid pitch or creating a zero-sized dumb buffer.
Fix this by using check_add_overflow() for the alignment round-up and
check_mul_overflow() for the final pitch calculation, returning 0 on
overflow. Also reject zero pitch and size in
radeon_mode_dumb_create().
Found via AST-based call-graph analysis using sqry. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: ath11k: cancel SSR work items during PCI shutdown
A reboot can crash the kernel if it overlaps with WLAN firmware crash
recovery (SSR). The crash is a NULL pointer dereference in the MHI teardown
path while freeing DMA-backed MHI contexts.
Simplified trace:
dma_free_attrs
mhi_deinit_dev_ctxt [mhi]
ath11k_pci_power_down [ath11k_pci]
ath11k_pci_shutdown [ath11k_pci]
device_shutdown
kernel_restart
On the host side, SSR is driven by the MHI RDDM callback, which queues
reset_work to perform device recovery. reset_work power-cycles the device
by calling ath11k_hif_power_down() followed by ath11k_hif_power_up(). The
power-down phase deinitializes MHI and frees DMA resources.
Shutdown/reboot runs fully asynchronously with this RDDM-driven SSR
recovery flow. As a result, the shutdown path
(ath11k_pci_shutdown() -> ath11k_pci_power_down()) can race with the SSR
recovery sequence.
Fix this by canceling SSR-related work items during PCI shutdown, marking
the device as unregistering, and serializing the RDDM callback path that
checks and queues reset_work. This ensures that no new SSR recovery work
can be queued once teardown has started, and that any in-flight recovery
work is fully synchronized before device power-down, preventing MHI
teardown and DMA resource freeing from running more than once.
Note: This issue only affects PCI/MHI-based devices. AHB-based ath11k
devices do not queue reset_work in normal SSR flows.
Tested-on: WCN6855 hw2.1 PCI WLAN.HSP.1.1-04866.5-QCAHSPSWPL_V1_V2_SILICONZ_IOE-1 |
| In the Linux kernel, the following vulnerability has been resolved:
vxlan: Fix potential null-ptr-deref in vxlan_gro_prepare_receive().
udp_tunnel_sock_release() could set sk->sk_user_data to NULL
while vxlan_gro_prepare_receive() is running.
Let's check if rcu_dereference_sk_user_data() is NULL after
skb_gro_remcsum_init(). |
| In the Linux kernel, the following vulnerability has been resolved:
OPP: Fix race between OPP addition and lookup
A race exists between dev_pm_opp_add_dynamic() and
dev_pm_opp_find_freq_exact():
CPU0 (add) CPU1 (lookup)
------------------------------- ------------------------------
_opp_add()
mutex_lock()
list_add(&new_opp->node, head)
mutex_unlock() _opp_table_find_key()
mutex_lock()
dev_pm_opp_get(opp)
kref_get()
mutex_unlock()
kref_init(&new_opp->kref)
dev_pm_opp_put()
kref_put_mutex()
The newly added OPP is inserted into the list before its kref is
initialized. A concurrent lookup can find this OPP and increment its
reference count while it is still uninitialized, leading to refcount
corruption and a potential premature free.
Fix this by initializing ->kref and ->opp_table before making the OPP
visible via list_add(). This ensures any concurrent lookup observes a
fully initialized object.
[ Viresh: Updated commit log ] |
