| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
posix-cpu-timers: Prevent freeing a timer which is queued on the expiry list
Kijo analyzed another race in the POSIX CPU timer code:
Commit bf635681c906 converted cpu_timer::firing from a tristate value to a
boolean. This lost the distinction between "not owned by the firing list"
and "still owned, but delivery was canceled". The resulting race is:
expiry handler timer_settime() timer_delete()
-------------- --------------- --------------
collect timer onto
private firing list
firing = true
observes firing = true
firing = false
return TIMER_RETRY
wait for handler
observes firing = false
finish deletion
unhash and free timer
resume list traversal
read freed elist.next
-> UAF
The firing bit is clearly the wrong indicator since that commit.
Check whether the timer is queued on the expiry list or not instead. If it
is queued clear the firing bit to prevent signal delivery as before and
return TIMER_RETRY so the caller unlocks the timer which allows the expiry
code to make progress and remove it from the list. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: libipw: reject too-short association responses
libipw_handle_assoc_resp() reads the capability, status and aid fields
of the 30-byte association response prefix and then computes the
information element length as
stats->len - sizeof(*frame)
stats->len is a u16 and sizeof() has type size_t, so the subtraction is
evaluated as size_t and wraps instead of going negative. Truncating
that to the u16 length parameter of libipw_parse_info_param() turns a
frame shorter than the fixed fields into a length near 64 KiB, and the
parser then reads past the receive buffer.
Both the ipw2100 and ipw2200 management receive paths reach this
function having established only that the frame carries the generic
24-byte three-address header.
Reject the frame before any fixed field is touched.
Found by an AI-assisted review of length arithmetic in management frame
parsers. Verified with a KUnit case under Generic KASAN on arm64 under
QEMU; I do not have the hardware, so it is not tested on a real device. |
| In the Linux kernel, the following vulnerability has been resolved:
mips: select CONFIG_WEAK_REORDERING_BEYOND_LLSC from CONFIG_EYEQ
On I6500 CPU cores, lld and scd give no ordering guarantees (same as all
other instructions). To respect the assumption that arch_cmpxchg() is
fully ordered, we must inject sync instructions above and below our
lld/scd loops using the already in place WEAK_REORDERING_BEYOND_LLSC
infrastructure.
Otherwise, bad things can happen:
[ 34.054496] CPU 3 Unable to handle kernel paging request at virtual address 0000000000000000, epc == a80000080838e01c, ra == a80000080838dfc4
[ 34.054559] Oops[#1]:
[ 34.069561] CPU: 3 UID: 0 PID: 170 Comm: pipe_race Not tainted 7.2.0-rc6-01553-gb73c35220968-dirty #103 VOLUNTARY
[ 34.079932] Hardware name: Mobile EyeQ5 MP5 Evaluation board
[ 34.085592] $ 0 : 0000000000000000 0000000000000001 0000000000000000 0000000000000000
[ 34.093616] $ 4 : a800000808ee2618 000000000b7a879d 0000000000001000 0000000000000000
[ 34.101638] $ 8 : 0000000000e3f2c9 0000000000000000 a800000808a2a9f8 0000000000000000
[ 34.109660] $12 : a8000008139ffcd8 ffffffff84080018 a80000080837fae0 7878787878787878
[ 34.117682] $16 : a800000807e82940 0000000000001000 0000000000000000 0000000000000000
[ 34.125704] $20 : a800000802920e00 a8000008139ffdf8 a800000802649400 0000000000e3f2c9
[ 34.133726] $24 : 0000000000000006 00000001200406e0
[ 34.141783] $28 : a8000008139fc000 a8000008139ffd10 0000000000e3f2c8 a80000080838dfc4
[ 34.149837] epc : a80000080838e01c anon_pipe_read+0xd4/0x428
[ 34.155697] ra : a80000080838dfc4 anon_pipe_read+0x7c/0x428
[ 34.161549] Status: 140000e3 KX SX UX KERNEL EXL IE
[ 34.166551] Cause : 40800408 (ExcCode 02)
[ 34.170574] BadVA : 0000000000000000
[ 34.174161] PrId : 0001b028 (MIPS I6500)
[ 34.178183] Process pipe_race (pid: 170, threadinfo=000000005ca35720, task=00000000e1013890, tls=000000014ebbb780)
[ 34.188568] Stack : a800000802649400 0000000000000000 0000000000000000 a8000008139ffdd0
[ 34.196623] 0000000000000fba a800000808ee0000 0000000000000001 a8000008130c3e80
[ 34.204676] a8000008080d1280 a8000008139ffd58 a8000008139ffd58 1dbd2b22ea1dd500
[ 34.212729] a800000802649400 a800000808ee0000 ffffffffffffffea 0000000000000001
[ 34.220783] 0000000000001000 0000000000000000 00000001200ae518 ffffffffffffffff
[ 34.228836] 000000fffbe0e530 a80000080837edf4 000000fffbe0e530 0000000000000000
[ 34.236890] 0000000000000000 0000000000000000 000000014ebb55a0 0000000000001000
[ 34.244943] 0000000000000001 a800000802649400 0000000000000000 0000000000000000
[ 34.252996] 0000000000000000 0000400400000000 0000000000000000 1dbd2b22ea1dd500
[ 34.261049] 00000000140000e3 a800000802649400 a800000802649400 a800000808ee0000
[ 34.269103] ...
[ 34.271568] Call Trace:
[ 34.274026] [<a80000080838e01c>] anon_pipe_read+0xd4/0x428
[ 34.279533] [<a80000080837edf4>] vfs_read+0x25c/0x318
[ 34.284607] [<a80000080837faac>] ksys_read+0x104/0x138
[ 34.289763] [<a80000080802b9cc>] syscall_common+0x44/0x68
[ 34.295187]
[ 34.296689] Code: f84000cf 02209825 de020010 <dc420000> d8400004 02002825 0040f809 02802025 f84000c3
[ 34.306504]
[ 34.308099] ---[ end trace 0000000000000000 ]---
My initial reproducer was the xdp-tools test suite. A standalone
reproducer would be an lld/scd loop that, when the read is reordered by
the CPU, triggers a fault. We can achieve this from userspace by
stressing an anonymous pipe, which uses a mutex. Program used:
// SPDX-License-Identifier: GPL-2.0
// pipe_race.c - reproducer for MIPS LL/SC reordering vs fs/pipe.c
//
// Two userspace processes on an anonymous pipe:
// parent = writer: tight write() loop
// child = reader: tight read() loop
#define _GNU_SOURCE
#include <assert.h>
#include <errno.h>
#include <sched.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: PPC: Book3S HV: fix use-after-free in kvmhv_emulate_tlbie_all_lpid()
kvmhv_emulate_tlbie_all_lpid() iterates the nested-guest IDR and drops
mmu_lock before calling kvmhv_emulate_tlbie_lpid(), but does not hold a
reference on the kvm_nested_guest pointer obtained from the IDR. A
concurrent vCPU issuing a single-LPID tlbie (is=2, ric=2) can race
through kvmhv_flush_nested() -> kvmhv_remove_nested() -> idr_remove /
--refcnt -> kvmhv_release_nested() -> kfree(gp) in that window, leaving
the iterating vCPU with a dangling pointer. The subsequent
mutex_lock(&gp->tlb_lock) and accesses to gp->shadow_pgtable,
gp->shadow_lpid and gp->l1_host all touch freed memory. The free path
is fully L1-controlled.
Fix this by incrementing gp->refcnt inside the loop before dropping
mmu_lock, mirroring what kvmhv_get_nested() does, and releasing the
reference with kvmhv_put_nested() after the per-guest work completes.
This is the same get/put discipline already used at every other
call site that drops mmu_lock while holding a nested-guest pointer. |
| In the Linux kernel, the following vulnerability has been resolved:
ntfs: protect runlist updates with the runlist lock
ntfs_non_resident_attr_shrink() calls runlist helpers that require the
runlist write lock, but did not hold it while freeing clusters and
truncating the runlist. Serialize those operations and the resident
conversion with the runlist lock.
ntfs_attr_map_cluster() can merge a newly allocated run before updating
mapping pairs. If the update fails, free the clusters and restore both
the in-memory runlist and on-disk mapping pairs from a saved runlist.
Mark the volume in error if either rollback step fails. |
| In the Linux kernel, the following vulnerability has been resolved:
RDMA/siw: Bound fragmented header copies by the remaining length
siw_get_hdr() can receive an extended DDP/RDMAP header across more than
one TCP callback. The first callback may receive most of the header,
while the next one still limits the copy to hdrlen - MIN_DDP_HDR instead
of the number of missing bytes. This makes the destination move past the
end of the header and overwrite the receive state, including
fpdu_part_rcvd. A later callback can then use a negative fpdu_part_rcvd
value as a copy offset, which creates an OOB write.
Use the number of header bytes already received when calculating the
next copy length. |
| In the Linux kernel, the following vulnerability has been resolved:
mmc: sdio_uart: fix xmit_fifo leak when the port table is full
sdio_uart_add_port() allocates the transmit fifo before claiming a
slot in sdio_uart_table[]. When all UART_NR slots are taken, it
returns -EBUSY with the fifo still allocated, but the probe error
path only kfree()s the port, leaking the transmit fifo.
Free the fifo in the failure path of sdio_uart_add_port() itself so
the function retains nothing on error. |
| In the Linux kernel, the following vulnerability has been resolved:
xfrm: save input state data before secpath resets
xfrm_input() stores the current xfrm_state in the skb secpath while it
continues receive-side processing. Some input paths can reset that secpath
before xfrm_input() has finished dereferencing the state.
Receive callback users such as VTI and XFRM interfaces can reset the
secpath. The VTI receive path does so before checking whether the packet
crosses network namespaces, while the XFRM interface path does so only for
cross-network-namespace packets. The XFRM_MAX_DEPTH error path can also
reset the secpath before the final drop callback reports the current
state's protocol.
If secpath_reset() drops the last state reference while the state is
concurrently deleted, xfrm_input() can still dereference the freed state
when selecting transport_finish() or reporting the drop callback protocol.
Save the state protocol on the stack while the state is still valid,
and use the already saved address family for transport_finish(). A larval
XFRM_STATE_ACQ state has no type, so retain nexthdr as its protocol. This
preserves the existing drop-path fallback while avoiding the post-reset
state dereferences without adding an extra state reference to every
received packet. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: libipw: reject too-short beacon and probe responses
libipw_process_probe_response() and the libipw_network_init() call it
makes assume the frame contains the full 36-byte beacon and probe
response prefix, but the ipw2100 and ipw2200 receive paths only
establish that a management frame carries the generic 24-byte
three-address header.
libipw_network_init() then computes the information element length as
stats->len - sizeof(*beacon)
stats->len is a u16 and sizeof() has type size_t, so the subtraction is
evaluated as size_t and wraps instead of going negative. Truncating
that to the u16 length parameter of libipw_parse_info_param() yields
65524 for a 24-byte beacon, and the parser then walks the receive
buffer as if it held almost 64 KiB of information elements, reading
past the allocation.
Reject the frame before any fixed field is touched.
Found by an AI-assisted review of length arithmetic in management frame
parsers. Verified with a KUnit case under Generic KASAN on arm64 under
QEMU; I do not have the hardware, so it is not tested on a real device. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mwifiex: bound the pairwise-cipher OUI walk to the IE length
mwifiex_search_oui_in_ie() reads a pairwise-cipher (PTK) count from a
beacon/probe-response RSN or WPA information element and then walks that
many 4-byte OUIs, comparing each with memcmp(). The count comes straight
from the (attacker-supplied) IE and is never checked against the
element's own length, and the callers admit the element on element_id
alone (has_ieee_hdr() / has_vendor_hdr(), no length check). A crafted
RSN/WPA IE with a large pairwise count therefore makes the walk read up
to 255 * 4 bytes past the element -- an out-of-bounds read of the
kmemdup()'d beacon buffer, reachable from any AP whose beacon/probe
response is processed during scan-result parsing.
Pass the number of IE bytes available at the OUI list and bound the walk
to the element. Keep the length signed and reject a negative value
before any unsigned arithmetic, so a small or zero IE length cannot
underflow to a large size_t and defeat the bound.
Found by 0sec automated security-research tooling (https://0sec.ai). |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: mcast: use copy-on-write RCU updates in ip6_mc_source()
pmc->sflist is read locklessly under rcu_read_lock() by
inet6_mc_check() during packet reception in the UDP and RAW
multicast receive paths.
ip6_mc_source() mutated psl->sl_addr and psl->sl_count in-place
when adding or removing a source filter. Additionally, when expanding
the filter buffer, newpsl was published via rcu_assign_pointer()
before writing the new source into the array.
Because 16-byte struct in6_addr writes are not atomic and array
shifting is not synchronized with RCU readers, concurrent readers in
inet6_mc_check() could read torn IPv6 addresses or observe
duplicated/missed source entries.
Fix this by switching ip6_mc_source() to copy-on-write RCU updates:
allocate and fully populate newpsl before publishing it via
rcu_assign_pointer(), and reclaim the old filter via kfree_rcu(),
matching ip6_mc_msfilter().
Also remove the now unused IP6_SFBLOCK macro. |
| In the Linux kernel, the following vulnerability has been resolved:
ipv6: xfrm: use full sockets in local error paths
xfrm6_local_rxpmtu() and xfrm6_local_error() dereference skb->sk as if it
always pointed at a full IPv6 socket.
That is not guaranteed. TCP SYN-ACK skbs can be owned by a
TCP_NEW_SYN_RECV request_sock while the output path itself is driven by the
full listener. If rerouting selects an IPv6 XFRM tunnel route with a lower
MTU, the local PMTU/error handling path can reach these callbacks with that
mini-socket still attached to the skb.
The callbacks then miscast the request socket as a full inet/IPv6 socket and
can read beyond the request_sock allocation when they access inet_sock or
ipv6_pinfo state.
Resolve the owner with skb_to_full_sk() in both callbacks and bail out when
no full socket is attached. This matches the surrounding XFRM IPv6 PMTU/error
logic, which already reasons about full sockets with skb_to_full_sk(). |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/iommu: Fix the overflow validation in iommu_tce_check_ioba
The commit b1af23d836f8 ("KVM: PPC: iommu: Unify TCE checking") unified
IOBA parameter checking across KVM and VFIO into iommu_tce_check_ioba().
While doing so, the passed in argument npages is ignored and constant
value '1' is used leaving out a possible overflow as the callers can
legitimately be using npages > 1 for H_STUFF_TCE or H_PUT_TCE_INDIRECT
cases.
Fix this by accounting for 'npages', checking for arithmetic overflow,
and verifying that the entire requested range (ioba - offset + npages)
does not exceed the table capacity 'size'. |
| In the Linux kernel, the following vulnerability has been resolved:
ata: libahci: clear PxCLBU and PxFBU for AHCI_HFLAG_32BIT_ONLY
A user reported that commit 105c42566a55 ("ata: ahci: force 32-bit DMA for
JMicron JMB582/JMB585") made the JMicron JMB585 unusable on his board.
The failure is seen as soon as the ahci driver is probed, and booting with
iommu=off does not solve the problem.
Looking at the AHCI specification, PxCLBU and PxFBU are both read only '0'
for HBAs that do not support 64-bit addressing.
For HBAs that do support 64-bit addressing, the registers are read write,
with a reset value that is Implementation Specific.
When using the AHCI_HFLAG_32BIT_ONLY flag, the HBA does support 64-bit
addressing, and a 32-bit DMA mask is set by simply clearing HOST_CAP_64.
Thus, in this case, we need to explicitly clear the registers to 0. |
| In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: mesh: release the channel if start fails
ieee80211_join_mesh() acquires a channel context and then calls
ieee80211_start_mesh(), which can fail. In that case, the chanctx
isn't released then interface removal will attempt to unassign it
after it's removed from the driver, hitting:
wlan0: Failed check-sdata-in-driver check, flags: 0x0
WARNING: net/mac80211/driver-ops.c:366 at drv_unassign_vif_chanctx
ieee80211_assign_link_chanctx
__ieee80211_link_release_channel
ieee80211_link_release_channel
ieee80211_teardown_sdata
unregister_netdevice_many_notify
_cfg80211_unregister_wdev
ieee80211_remove_interfaces
ieee80211_unregister_hw
mac80211_hwsim_del_radio
hwsim_exit_net
Correctly release the channel on start failures. |
| In the Linux kernel, the following vulnerability has been resolved:
dma-buf/dma-fence: fix checking signaling bit for timeline and driver name v3
The patch "dma-buf: dma-fence: Fix potential NULL pointer dereference"
changed the check to test for the ops pointer instead of the signaled
bit to avoid a potential NULL dereference when the ops pointer has been
cleared.
The problem is now that the ops pointer is cleared only when neither the
release nor the wait callback is implemented and this isn't true for a lot
of dma_fence implementations yet. So those implementations lost the RCU
protection after signaling of the returned string resulting in potential
use after free.
Add the signaling check additional to the ops pointer check so that we
have both the protection against NULL dereference as well as the RCU
protection after signaling for the returned string.
v2: improve comments to note RCU protection and explain why we check
both signaling state and ops pointer
v3: some comment improvements suggested by Philip |
| In the Linux kernel, the following vulnerability has been resolved:
openvswitch: avoid reallocating confirmed conntrack labels
ovs_ct_get_conn_labels() adds the labels extension when a conntrack
entry does not have one. Confirmed conntracks can be read locklessly,
so adding an extension may reallocate and free the extension block
while another CPU accesses it.
Only add the extension for unconfirmed conntracks. A confirmed
conntrack without labels now fails the caller's label operation instead
of reallocating its extension storage. |
| In the Linux kernel, the following vulnerability has been resolved:
signal: Prevent exec() race
Hyunwoo debugged the following KASAN UAF splat:
BUG: KASAN: slab-use-after-free in __send_signal_locked+0xb27/0xba0
Write of size 8 at addr ffff888007ed80c8 by task poc/79
...
Call Trace:
__send_signal_locked+0xb27/0xba0
do_send_sig_info+0xa7/0x160
do_send_specific+0x76/0xa0
__x64_sys_tgkill+0x193/0x270
...
Allocated by task 80:
do_timer_create+0x1a4/0x1030
__x64_sys_timer_create+0x145/0x190
...
Freed by task 12:
kmem_cache_free_bulk+0x1f8/0x4a0
kvfree_rcu_bulk+0x14f/0x1c0
kfree_rcu_work+0x128/0x1a0
...
Last potentially related work creation:
kvfree_call_rcu+0x39/0x390
__flush_itimer_signals+0x211/0x320
flush_itimer_signals+0x47/0x90
begin_new_exec+0xa6b/0x28c0
It turned out that this happens with a non-leader exec() as Hyunwoo
explained:
de_thread() calls exchange_tids() before release_task(leader), so the
struct pid held by a SIGEV_THREAD_ID timer created against the leader's tid
now points to the thread which called execve(). pid_task() returns that
thread and lock_task_sighand() on it succeeds.
If the timer signal is blocked, its sigqueue stays queued on the leader's
task::pending. The next expiry of that timer can then run while
release_task() flushes the queue.
posixtimer_send_sigqueue() checks whether the sigqueue is already queued
with a plain list_empty(), which only reads list_head::next.
list_del_init() is not atomic and INIT_LIST_HEAD() stores list_head::next
before list_head::prev, so the check can pass in between. list_add_tail()
queues the entry on the task::pending of the live thread, and the
list_head::prev store from the flush then overwrites the list_head::prev
link that list_add_tail() has just set.
__flush_itimer_signals() does not undo that either. With list_head::prev
pointing at the entry itself, its list_del_init() only stores the same
values again, so the entry is not removed from the list. It is still there
after the last reference is dropped and the timer is freed by RCU, and the
list_add_tail() of a later tgkill() follows that list_head::prev into the
freed timer.
This problem surfaced with the recent commit which moved the sigqueue flush
out of the sighand lock held region.
Hyonwoo proposed to fix this by using list_del_init_careful(), but that
just papers over the problem. After some disucssions and various attempts
to solve it, Eric pointed out that there is no reason to flush
task::pending late in release_task() and it should be done in
exit_signals() already.
As nothing can collect and deliver signals which are queued in a dying
task's pending queue, there is no reason to delay it further.
But it has to be ensured that no signals can be queued into it after that
point. exit_signals() sets PF_EXITING in task::flags, which can be used as
an indicator for this.
Cure it by:
- Preventing signal queueing for task private signals (PIDTYPE_PID) when
the task has PF_EXITING set in __send_signal_locked() and in
posixtimer_send_sigqueue().
- Protecting the unlocked setting of PF_EXITING in exit_signals() for the
task group empty and the group exit case with sighand lock
- Flushing task::pending signals right there.
Optimize that by moving the whole pending list to an on-stack list head
under sighand lock and free the signals without the lock held.
There has been quite some discussion about the lockless flush and the
non-leader exec case on weakly ordered systems. The problem is that a third
party which tries to send a posix timer signal relies on the PID lookup to
find the target task and that lookup might result in the new leader when
the signal was originaly directed to the old leader. In case that the
signal was queued on the old leader then the lockless flush raised a
concern over the following situation:
old_leader new_leader third party
A: flush_list() // list_del_in
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
smb: client: validate absolute native symlink targets before NT fixups
With symlinkroot unset, an absolute target is copied without conversion
to an NT drive path. Later code still assumes an NT prefix is present
when modifying the target and calculating the print name length.
For "/ab", this causes two failures: sym[5] and path[5] are written
past their allocations, and plen -= 2 * poff subtracts an assumed
8-byte prefix from a 6-byte UTF-16 target, wrapping u16 plen to 65534.
That underflow causes another overflow: memcpy() copies 65534 bytes
into a 24-byte buffer. A user with write access to a mounted share
can trigger these bugs with default settings.
Validate the NT drive prefix, including an ASCII drive letter, before
accessing fixed offsets or subtracting the prefix length. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: flowtable: hold reference on ct until flow is released
nf_ct_put() releases the ct->ext area inmediately, the rcu typesafe
semantics also allow to refer to the wrong conntrack from the flowtable
datapath. Hold reference on ct until flow is released after rcu grace
period.
Add rcu_barrier() on module exit path, to ensure pending flow entries
are release before module goes away. |
