In the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: capture fast-RX rate before mesh reuses skb->cb
ieee80211_invoke_fast_rx() reads RX status through
IEEE80211_SKB_RXCB(skb), which alia...Show moreIn the Linux kernel, the following vulnerability has been resolved:
wifi: mac80211: capture fast-RX rate before mesh reuses skb->cb
ieee80211_invoke_fast_rx() reads RX status through
IEEE80211_SKB_RXCB(skb), which aliases the same skb->cb storage
that ieee80211_rx_mesh_data() reuses as IEEE80211_TX_INFO. In the
unicast forward path, mesh_data does:
info = IEEE80211_SKB_CB(fwd_skb);
memset(info, 0, sizeof(*info));
on the same skb the caller still names via rx->skb, then either
queues the skb for TX (success) or kfree_skb()'s it (no-route)
before returning RX_QUEUED. The caller's RX_QUEUED arm then
calls sta_stats_encode_rate(status) on memory that is either
zeroed (success path) or freed (no-route path). The latter is
KASAN slab-use-after-free in ieee80211_prepare_and_rx_handle.
Fix by encoding the rate from status before invoking
ieee80211_rx_mesh_data(), so the RX_QUEUED arm consumes a value
captured while status was still backed by valid memory.Show less |
In the Linux kernel, the following vulnerability has been resolved:
vsock/vmci: fix UAF when peer resets connection during handshake
vmci_transport_recv_connecting_server() returned err = 0 for a peer
RST in its defaul...Show moreIn the Linux kernel, the following vulnerability has been resolved:
vsock/vmci: fix UAF when peer resets connection during handshake
vmci_transport_recv_connecting_server() returned err = 0 for a peer
RST in its default switch arm:
err = pkt->type == VMCI_TRANSPORT_PACKET_TYPE_RST ? 0 : -EINVAL;
That made vmci_transport_recv_listen() skip vsock_remove_pending(),
leaving the pending socket on the listener's pending_links with
sk_state = TCP_CLOSE while destroy: still dropped the explicit
reference taken before schedule_delayed_work().
One second later vsock_pending_work() observed is_pending=true and
performed full cleanup: vsock_remove_pending() then the two trailing
sock_put(sk) calls -- the first reached refcount 0 and __sk_freed
the socket, and the second wrote into the freed object:
BUG: KASAN: slab-use-after-free in refcount_warn_saturate
Write of size 4 at addr ffff88800b1cac80 by task kworker
Workqueue: events vsock_pending_work
Treat peer RST like any other unexpected packet type (err = -EINVAL).
All destroy: arms now return err < 0, so vmci_transport_recv_listen()
removes pending from pending_links synchronously and
vsock_pending_work() takes the is_pending=false / !rejected branch,
dropping only its own work reference. This also closes the
multi-packet race Sashiko reported on v2: pending is removed from
the list before any subsequent packet can find it.
The pre-existing sk_acceptq_removed() gap on the err < 0 path of
vmci_transport_recv_listen() that Sashiko also noted is not
introduced or changed by this patch.
Tested on lts-6.12.79 with KASAN: 52/100 unpatched -> 0/100 patched.Show less |
In the Linux kernel, the following vulnerability has been resolved:
ixgbevf: fix use-after-free in VEPA multicast source pruning
ixgbevf_clean_rx_irq() prunes frames whose source MAC matches the VF's
own address (VEPA...Show moreIn the Linux kernel, the following vulnerability has been resolved:
ixgbevf: fix use-after-free in VEPA multicast source pruning
ixgbevf_clean_rx_irq() prunes frames whose source MAC matches the VF's
own address (VEPA multicast workaround) by freeing the skb and
continuing to the next descriptor:
dev_kfree_skb_irq(skb);
continue;
The skb pointer is declared outside the while loop and persists across
iterations. Because the continue skips the "skb = NULL" reset at the
bottom of the loop, the next iteration enters the "else if (skb)" path
and calls ixgbevf_add_rx_frag() on the freed skb, dereferencing
skb_shinfo(skb)->nr_frags - a use-after-free in NAPI softirq context.
The sibling driver iavf already handles this correctly by nulling the
pointer before continuing. Apply the same pattern here.
I do not have ixgbevf hardware; the bug was found by static analysis
(scan_drop_continue_loops.py + semgrep drop_continue_in_loop, multi-tool
corroboration with the highest score in the scan). The UAF was confirmed
under KASAN by loading a test module that reproduces the exact code
pattern (alloc skb, kfree_skb, then read skb_shinfo(skb)->nr_frags):
BUG: KASAN: slab-use-after-free in ixgbevf_uaf_test_init+0x100/0x1000
Read of size 8 at addr 000000006163ae78 by task insmod/30
freed 208-byte region [000000006163adc0, 000000006163ae90)
QEMU emulates igb (82576) but not ixgbe (82599), and the igbvf VF
driver does not include the VEPA source pruning path, so a full
end-to-end reproduction with emulated hardware was not possible.Show less |
In the Linux kernel, the following vulnerability has been resolved:
af_unix: Fix UAF read of tail->len in unix_stream_data_wait()
unix_stream_data_wait() does skb_peek_tail(&sk->sk_receive_queue) without
holding any lo...Show moreIn the Linux kernel, the following vulnerability has been resolved:
af_unix: Fix UAF read of tail->len in unix_stream_data_wait()
unix_stream_data_wait() does skb_peek_tail(&sk->sk_receive_queue) without
holding any lock that prevents SKBs on that queue from being dequeued and
freed.
This has been the case since commit 79f632c71bea ("unix/stream: fix
peeking with an offset larger than data in queue").
The first consequence of this is that the pointer comparison
`tail != last` can be false even if `last` semantically refers to an
already-freed SKB while `tail` is a new SKB allocated at the same address;
which can cause unix_stream_data_wait() to wrongly keep blocking after new
data has arrived, but only in a weird scenario where a peeking recv() and
a normal recv() on the same socket are racing, which is probably not a
real problem.
But since commit 2b514574f7e8 ("net: af_unix: implement splice for stream
af_unix sockets"), `tail` is actually dereferenced, which can cause UAF in
the following race scenario (where test_setup() runs single-threaded,
and afterwards, test_thread1() and test_thread2() run concurrently in
two threads:
```
static int socks[2];
void test_setup(void) {
socketpair(AF_UNIX, SOCK_STREAM, 0, socks);
send(socks[1], "A", 1, 0);
int peekoff = 1;
setsockopt(socks[0], SOL_SOCKET, SO_PEEK_OFF, &peekoff, sizeof(peekoff));
}
void test_thread1(void) {
char dummy;
recv(socks[0], &dummy, 1, MSG_PEEK);
}
void test_thread2(void) {
char dummy;
recv(socks[0], &dummy, 1, 0);
shutdown(socks[1], SHUT_WR);
}
```
when racing like this:
```
thread1 thread2
unix_stream_read_generic
mutex_lock(&u->iolock)
skb_peek(&sk->sk_receive_queue)
skb_peek_next(skb, &sk->sk_receive_queue)
mutex_unlock(&u->iolock)
unix_stream_read_generic
unix_state_lock(sk)
skb_peek(&sk->sk_receive_queue)
unix_state_unlock(sk)
unix_stream_data_wait
unix_state_lock(sk)
tail = skb_peek_tail(&sk->sk_receive_queue)
spin_lock(&sk->sk_receive_queue.lock)
__skb_unlink(skb, &sk->sk_receive_queue)
spin_unlock(&sk->sk_receive_queue.lock)
consume_skb(skb) [frees the SKB]
`tail != last`: false
`tail`: true
`tail->len != last_len` ***UAF***
```
Fix the UAF by removing the read of tail->len; checking tail->len would
only make sense if SKBs in the receive queue of a UNIX socket could grow,
which can no longer happen.
Kuniyuki explained:
> When commit 869e7c62486e ("net: af_unix: implement stream sendpage
> support") added sendpage() support, data could be appended to the last
> skb in the receiver's queue.
>
> That's why we needed to check if the length of the last skb was changed
> while waiting for new data in unix_stream_data_wait().
>
> However, commit a0dbf5f818f9 ("af_unix: Support MSG_SPLICE_PAGES") and
> commit 57d44a354a43 ("unix: Convert unix_stream_sendpage() to use
> MSG_SPLICE_PAGES") refactored sendmsg(), and now data is always added
> to a new skb.
That means this fix is not suitable for kernels before 6.5.Show less |
In the Linux kernel, the following vulnerability has been resolved:
scsi: isci: Fix use-after-free in device removal path
The ISCI completion tasklet is initialized in isci_host_alloc()
(drivers/scsi/isci/init.c:496) a...Show moreIn the Linux kernel, the following vulnerability has been resolved:
scsi: isci: Fix use-after-free in device removal path
The ISCI completion tasklet is initialized in isci_host_alloc()
(drivers/scsi/isci/init.c:496) and scheduled from both MSI-X and legacy
interrupt handlers (drivers/scsi/isci/host.c:223,613).
isci_host_deinit() stops the controller and waits for stop completion,
but it never kills completion_tasklet before teardown continues. A
top-of-function tasklet_kill() is not sufficient here: interrupts are
only disabled when isci_host_stop_complete() runs, so until
wait_for_stop() returns the IRQ handlers can still requeue the
tasklet. The tasklet callback also re-enables interrupts after draining
completions, so killing the tasklet before the source is quiesced leaves
the same race open.
Once wait_for_stop() returns, no further IRQ-driven scheduling can
occur. Kill completion_tasklet there so teardown cannot race a queued
tasklet running on a dead ihost. On remove or unload, the stale callback
can otherwise dereference ihost and touch ihost->smu_registers after the
host lifetime ends.
A UML + KASAN analogue reproduced the failure class both with no
tasklet_kill() and with tasklet_kill() placed before source quiesce, and
stayed clean once the kill happened after quiescing the scheduling
source.
This mirrors commit f6ab594672d4 ("scsi: aic94xx: fix use-after-free in
device removal path"), but ISCI needs the kill after wait_for_stop().Show less |
In the Linux kernel, the following vulnerability has been resolved:
drm/v3d: Fix use-after-free of CPU job query arrays on error path
The CPU job ioctl's fail label calls kvfree() on cpu_job's timestamp and
performance...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/v3d: Fix use-after-free of CPU job query arrays on error path
The CPU job ioctl's fail label calls kvfree() on cpu_job's timestamp and
performance query arrays after v3d_job_cleanup(), which drops the job's
last reference and frees cpu_job. Reading cpu_job at that point is a
use-after-free. Also, on the early v3d_job_init() failure path, it is a
NULL dereference, since v3d_job_deallocate() zeroes the local pointer.
In the success path, the arrays are released from the scheduler's
.free_job callback, but on the error path, they are freed manually, as
the job was never pushed to the scheduler. While the success path deals
with this correctly, the fail path doesn't.
On top of that, the manual kvfree() calls only free the array storage;
they don't drm_syncobj_put() the per-query syncobjs that
v3d_timestamp_query_info_free() and v3d_performance_query_info_free()
release on the success path. So the same fail path that triggers the
use-after-free also leaks one syncobj reference per query.
Unify the CPU job teardown into the CPU job's kref destructor, mirroring
v3d_render_job_free(). The scheduler's .free_job slot reverts to the
generic v3d_sched_job_free() and the fail label drops the manual
kvfree() calls, leaving a single teardown path that is reached from both
the scheduler and the ioctl error path. That removes the use-after-free,
the NULL dereference, and the syncobj leak by construction.Show less |
In the Linux kernel, the following vulnerability has been resolved:
batman-adv: mcast: fix use-after-free in orig_node RCU release
batadv_mcast_purge_orig() removes entries from RCU-protected hlists but
does not wait f...Show moreIn the Linux kernel, the following vulnerability has been resolved:
batman-adv: mcast: fix use-after-free in orig_node RCU release
batadv_mcast_purge_orig() removes entries from RCU-protected hlists but
does not wait for an RCU grace period before returning. Concurrent RCU
readers may still accesses references to those entries at the point of
removal. RCU-protected readers trying to operate on entries like
orig->mcast_want_all_ipv6_node will then access already freed memory.
Fix this by moving batadv_mcast_purge_orig() to batadv_orig_node_release(),
just before the call_rcu() invocation. This ensures RCU readers that were
active at purge time have drained before the orig_node memory is reclaimed.Show less |
In the Linux kernel, the following vulnerability has been resolved:
firmware: arm_ffa: Snapshot notifier callbacks under lock
Both notification handlers currently look up a notifier callback under
notify_lock, drop the...Show moreIn the Linux kernel, the following vulnerability has been resolved:
firmware: arm_ffa: Snapshot notifier callbacks under lock
Both notification handlers currently look up a notifier callback under
notify_lock, drop the lock, and then dereference the returned
notifier entry. A concurrent unregister can delete and free that
entry in the gap, leaving the handler to dereference stale memory.
Copy the callback pointer and callback data while notify_lock is
still held and invoke the callback only after the lock is dropped.
This keeps the existing callback execution model while removing the
use-after-free window in both the framework and non-framework
notification paths.Show less |
In the Linux kernel, the following vulnerability has been resolved:
fprobe: Fix unregister_fprobe() to wait for RCU grace period
Commit 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
changed fprobe t...Show moreIn the Linux kernel, the following vulnerability has been resolved:
fprobe: Fix unregister_fprobe() to wait for RCU grace period
Commit 4346ba1604093 ("fprobe: Rewrite fprobe on function-graph tracer")
changed fprobe to register struct fprobe to an rcu-hlist, but it forgot
to wait for RCU GP. Thus there can be use-after-free if the fprobe is
released right after unregistering. This can be happened on fprobe
event and sample module code.
To fix this issue, add synchronize_rcu() in unregister_fprobe().
Note that BPF is OK because fprobe is used as a part of
bpf_kprobe_multi_link. This unregisters its fprobe in
bpf_kprobe_multi_link_release() and it is deallocated via
bpf_kprobe_multi_link_dealloc(), which is invoked from
bpf_link_defer_dealloc_rcu_gp() RCU callback.
For BPF, this also introduced unregister_fprobe_async() which does
NOT wait for RCU grace priod.Show less |
In the Linux kernel, the following vulnerability has been resolved:
irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT
On PREEMPT_RT, non-HARD irq_work runs in per-CPU kthreads via
run_irq_workd(), so irq_...Show moreIn the Linux kernel, the following vulnerability has been resolved:
irq_work: Fix use-after-free in irq_work_single() on PREEMPT_RT
On PREEMPT_RT, non-HARD irq_work runs in per-CPU kthreads via
run_irq_workd(), so irq_work_sync() uses rcuwait() to wait for BUSY==0.
After irq_work_single() clears BUSY via atomic_cmpxchg(), it still
dereferences @work for irq_work_is_hard() and rcuwait_wake_up().
An irq_work_sync() caller on another CPU that enters after BUSY is cleared
can observe BUSY==0 immediately, return, and free the work before those
accesses complete — causing a use-after-free.
Fix this by wrapping run_irq_workd() in guard(rcu)() so that the entire
irq_work_single() execution is within an RCU read-side critical
section. Then add synchronize_rcu() in irq_work_sync() after
rcuwait_wait_event() to ensure the caller waits for the RCU grace period
before returning, preventing premature frees.Show less |
In the Linux kernel, the following vulnerability has been resolved:
nvme-pci: fix use-after-free in nvme_free_host_mem()
nvme_free_host_mem() frees dev->hmb_sgt via dma_free_noncontiguous()
but never clears the pointer...Show moreIn the Linux kernel, the following vulnerability has been resolved:
nvme-pci: fix use-after-free in nvme_free_host_mem()
nvme_free_host_mem() frees dev->hmb_sgt via dma_free_noncontiguous()
but never clears the pointer afterward. This leads to a use-after-free
if nvme_free_host_mem() is called twice in the same error path.
This can happen during nvme_probe() when nvme_setup_host_mem() succeeds
in allocating the HMB (setting dev->hmb_sgt) but nvme_set_host_mem()
fails with an I/O error:
nvme_setup_host_mem()
nvme_alloc_host_mem_single() -> sets dev->hmb_sgt
nvme_set_host_mem() -> fails with -EIO
nvme_free_host_mem() -> frees hmb_sgt, but does NOT NULL it
return error
nvme_probe() error path:
nvme_free_host_mem() -> dev->hmb_sgt is stale, use-after-free
The second call dereferences the freed sgt, causing a NULL pointer
dereference in iommu_dma_free_noncontiguous() when it accesses
sgt->sgl->dma_address (the backing memory has been freed and zeroed).
This is reproducible on Thunderbolt-attached NVMe devices (e.g., OWC
Envoy Express behind a Dell WD22TB4 dock) where the device intermittently
returns I/O errors during HMB setup due to PCIe link instability.
BUG: kernel NULL pointer dereference, address: 0000000000000010
RIP: 0010:iommu_dma_free_noncontiguous+0x22/0x80
Call Trace:
<TASK>
dma_free_noncontiguous+0x3b/0x130
nvme_free_host_mem+0x30/0xf0 [nvme]
nvme_probe.cold+0xcc/0x275 [nvme]
local_pci_probe+0x43/0xa0
pci_device_probe+0xeea/0x290
really_probe+0xf9/0x3b0
__driver_probe_device+0x8b/0x170
driver_probe_device+0x24/0xd0
__driver_attach_async_helper+0x6b/0x110
async_run_entry_fn+0x37/0x170
process_one_work+0x1ac/0x3d0
worker_thread+0x1b8/0x360
kthread+0xf7/0x130
ret_from_fork+0x2d8/0x3a0
ret_from_fork_asm+0x1a/0x30
</TASK>
Fix this by setting dev->hmb_sgt to NULL after freeing it, so the
second call takes the multi-descriptor path which safely handles the
already-cleaned-up state.Show less |
In the Linux kernel, the following vulnerability has been resolved:
netfs: Fix early put of sink folio in netfs_read_gaps()
Fix netfs_read_gaps() to release the sink page it uses after waiting for
the request to comple...Show moreIn the Linux kernel, the following vulnerability has been resolved:
netfs: Fix early put of sink folio in netfs_read_gaps()
Fix netfs_read_gaps() to release the sink page it uses after waiting for
the request to complete. The way the sink page is used is that an
ITER_BVEC-class iterator is created that has the gaps from the target folio
at either end, but has the sink page tiled over the middle so that a single
read op can fill in both gaps.
The bug was found by KASAN detecting a UAF on the generic/075 xfstest in
the cifsd kernel thread that handles reception of data from the TCP socket:
BUG: KASAN: use-after-free in _copy_to_iter+0x48a/0xa20
Write of size 885 at addr ffff888107f92000 by task cifsd/1285
CPU: 2 UID: 0 PID: 1285 Comm: cifsd Not tainted 7.0.0 #6 PREEMPT(lazy)
Call Trace:
dump_stack_lvl+0x5d/0x80
print_report+0x17f/0x4f1
kasan_report+0x100/0x1e0
kasan_check_range+0x10f/0x1e0
__asan_memcpy+0x3c/0x60
_copy_to_iter+0x48a/0xa20
__skb_datagram_iter+0x2c9/0x430
skb_copy_datagram_iter+0x6e/0x160
tcp_recvmsg_locked+0xce0/0x1130
tcp_recvmsg+0xeb/0x300
inet_recvmsg+0xcf/0x3a0
sock_recvmsg+0xea/0x100
cifs_readv_from_socket+0x3a6/0x4d0 [cifs]
cifs_read_iter_from_socket+0xdd/0x130 [cifs]
cifs_readv_receive+0xaad/0xb10 [cifs]
cifs_demultiplex_thread+0x1148/0x1740 [cifs]
kthread+0x1cf/0x210Show less |
In the Linux kernel, the following vulnerability has been resolved:
accel/qaic: Add overflow check to remap_pfn_range during mmap
The call to remap_pfn_range in qaic_gem_object_mmap is susceptible to
(re)mapping beyond...Show moreIn the Linux kernel, the following vulnerability has been resolved:
accel/qaic: Add overflow check to remap_pfn_range during mmap
The call to remap_pfn_range in qaic_gem_object_mmap is susceptible to
(re)mapping beyond the VMA if the BO is too large. This can cause use
after free issues when munmap() unmaps only the VMA region and not the
additional mappings. To prevent this, check the remaining size of the
VMA before remapping and truncate the remapped length if sg->length is
too large.
[jhugo: fix braces from checkpatch --strict]Show less |
In the Linux kernel, the following vulnerability has been resolved:
drm/msm/dpu: don't mix devm and drmm functions
Mixing devm and drmm functions will result in a use-after-free on msm
driver teardown if userspace keep...Show moreIn the Linux kernel, the following vulnerability has been resolved:
drm/msm/dpu: don't mix devm and drmm functions
Mixing devm and drmm functions will result in a use-after-free on msm
driver teardown if userspace keeps a reference on the drm device:
The WB connector data will be destroyed because of the use of
devm_kzalloc()), while the usersoace still can try interacting with the
WB connector (which uses drmm_ functions).
Change dpu_writeback_init() to use drmm_.
Patchwork: https://patchwork.freedesktop.org/patch/722656/Show less |
In the Linux kernel, the following vulnerability has been resolved:
gfs2: fix use-after-free in gfs2_qd_dealloc
gfs2_qd_dealloc(), called as an RCU callback from gfs2_qd_dispose(),
accesses the superblock object sdp th...Show moreIn the Linux kernel, the following vulnerability has been resolved:
gfs2: fix use-after-free in gfs2_qd_dealloc
gfs2_qd_dealloc(), called as an RCU callback from gfs2_qd_dispose(),
accesses the superblock object sdp through qd->qd_sbd after freeing qd.
It does so to decrement sd_quota_count and wake up sd_kill_wait.
However, by the time the RCU callback runs, gfs2_put_super() may have
already freed sdp via free_sbd(). This can happen when
gfs2_quota_cleanup() is called during unmount: it disposes of quota
objects via call_rcu() and then waits on sd_kill_wait with a 60-second
timeout. If the timeout expires, or if gfs2_gl_hash_clear() triggers
additional qd_put() calls that schedule more RCU callbacks after the
wait completes, gfs2_put_super() will proceed to free the superblock
while RCU callbacks referencing it are still pending.
Add an rcu_barrier() before free_sbd() in gfs2_put_super() to ensure
all pending RCU callbacks (including gfs2_qd_dealloc) have completed
before the superblock is freed.Show less |
In the Linux kernel, the following vulnerability has been resolved:
hdlc_ppp: sync per-proto timers before freeing hdlc state
Each PPP control protocol (LCP/IPCP/IPV6CP) embedded in struct ppp
registers a timer via tim...Show moreIn the Linux kernel, the following vulnerability has been resolved:
hdlc_ppp: sync per-proto timers before freeing hdlc state
Each PPP control protocol (LCP/IPCP/IPV6CP) embedded in struct ppp
registers a timer via timer_setup(). That struct ppp is the
hdlc->state allocation, which detach_hdlc_protocol() frees with kfree()
in both teardown paths: unregister_hdlc_device() and the re-attach inside
attach_hdlc_protocol().
The ppp proto never registered a .detach callback, so
detach_hdlc_protocol() performs no timer synchronization before the
kfree(). The only cancel, timer_delete(&proto->timer) in ppp_cp_event(),
is partial (it does not wait for a running callback) and only runs on the
->CLOSED transition; ppp_stop()/ppp_close() do not sync either. A
ppp_timer callback already executing (blocked on ppp->lock) survives the
kfree and then dereferences proto->state / ppp->lock in freed memory,
leading to a use-after-free.
Fix this by adding a .detach helper that calls timer_shutdown_sync() on
every per-proto timer. detach_hdlc_protocol() invokes proto->detach(dev)
before kfree(hdlc->state), so timer_shutdown_sync()
now runs on both free paths.
timer_shutdown_sync() is used instead of timer_delete_sync() because the
keepalive path re-arms the timer through add_timer()/mod_timer() and
shutdown blocks any re-activation during teardown.
Initialize the per-protocol timers in ppp_ioctl() when the protocol is
attached, and remove the now-redundant timer_setup() from ppp_start(), so
that the timers are initialized exactly once at attach time and
ppp_timer_release() never operates on uninitialized timer_list
structures. attach_hdlc_protocol() uses kmalloc() (not kzalloc), so
struct ppp's protos[i].timer is uninitialized garbage until the first
timer_setup(); without this init-at-attach, attaching the PPP protocol
without ever bringing the device up would leave timer_shutdown_sync()
operating on uninitialized memory in .detach. Moving the init out of
ppp_start() (which only runs on NETDEV_UP) into the attach path makes the
initialization unconditional and avoids initializing the same timer_list
twice.
This bug was found by static analysis.Show less |
In the Linux kernel, the following vulnerability has been resolved:
blk-cgroup: fix UAF in __blkcg_rstat_flush()
When multiple blkgs in the same blkcg are released concurrently,
a use-after-free can occur. The race hap...Show moreIn the Linux kernel, the following vulnerability has been resolved:
blk-cgroup: fix UAF in __blkcg_rstat_flush()
When multiple blkgs in the same blkcg are released concurrently,
a use-after-free can occur. The race happens when one blkg's
__blkcg_rstat_flush() removes another blkg's iostat entries via
llist_del_all(). The second blkg sees an empty list and proceeds
to free itself while the first is still iterating over its entries.
Move the flush from __blkg_release() (RCU callback) to blkg_release()
(before call_rcu). This ensures the RCU grace period waits for any
concurrent flush's rcu_read_lock() section to complete before freeing.Show less |
In the Linux kernel, the following vulnerability has been resolved:
tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done
tipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to
crypto_aead_decrypt(req) wi...Show moreIn the Linux kernel, the following vulnerability has been resolved:
tipc: fix slab-use-after-free Read in tipc_aead_decrypt_done
tipc_aead_decrypt() goes straight from tipc_bearer_hold(b) to
crypto_aead_decrypt(req) without taking a reference on the netns, unlike
the encrypt path. When crypto_aead_decrypt() is offloaded asynchronously
(e.g. the SIMD aead wrapper queuing to cryptd), the cryptd worker runs
tipc_aead_decrypt_done() later. If the bearer's netns is torn down in the
meantime, cleanup_net() -> tipc_exit_net() -> tipc_crypto_stop() frees the
per-netns tipc_crypto, and the completion then reads it:
tipc_aead_decrypt_done() dereferences aead->crypto->stats and
aead->crypto->net, and tipc_crypto_rcv_complete() dereferences
aead->crypto->aead[] and the node table -- reading freed memory.
Decoded KASAN splat (v7.1-rc7, CONFIG_KASAN_INLINE + TIPC + TIPC_CRYPTO):
BUG: KASAN: slab-use-after-free in tipc_aead_decrypt_done (net/tipc/crypto.c:999)
Read of size 8 at addr ffff8881056258a8 by task kworker/u16:2/51
Workqueue: events_unbound
Call Trace:
tipc_aead_decrypt_done (net/tipc/crypto.c:999)
process_one_work (kernel/workqueue.c:3314)
worker_thread (kernel/workqueue.c:3397 kernel/workqueue.c:3478)
kthread (kernel/kthread.c:436)
ret_from_fork (arch/x86/kernel/process.c:158)
ret_from_fork_asm (arch/x86/entry/entry_64.S:245)
Allocated by task 169:
__kasan_kmalloc (mm/kasan/common.c:398 mm/kasan/common.c:415)
tipc_crypto_start (net/tipc/crypto.c:1502)
tipc_init_net (net/tipc/core.c:72)
ops_init (net/core/net_namespace.c:137)
setup_net (net/core/net_namespace.c:446)
copy_net_ns (net/core/net_namespace.c:579)
create_new_namespaces (kernel/nsproxy.c:132)
__x64_sys_unshare (kernel/fork.c:3316)
do_syscall_64 (arch/x86/entry/syscall_64.c:63)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Freed by task 8:
kfree (mm/slub.c:6566)
tipc_exit_net (net/tipc/core.c:119)
cleanup_net (net/core/net_namespace.c:704)
process_one_work (kernel/workqueue.c:3314)
kthread (kernel/kthread.c:436)
This is the same class of bug that commit e279024617134 ("net/tipc: fix
slab-use-after-free Read in tipc_aead_encrypt_done") fixed for the encrypt
side. The encrypt path takes maybe_get_net(aead->crypto->net) before
crypto_aead_encrypt() and drops it with put_net() on the synchronous
return paths and in tipc_aead_encrypt_done(); the -EINPROGRESS/-EBUSY
return keeps the reference for the async callback to release. The decrypt
path was left without the equivalent guard.
Mirror the encrypt-side fix on the decrypt path: take a net reference
before crypto_aead_decrypt() (failing with -ENODEV and the matching
bearer put if it cannot be acquired), keep it across the
-EINPROGRESS/-EBUSY async return, and drop it with put_net() on the
synchronous success/error return and at the end of
tipc_aead_decrypt_done().
Reproduced under KASAN on v7.1-rc7: a UDP bearer with a cluster key is
flooded with crafted encrypted frames from an unknown peer (driving the
cluster-key decrypt path) while the bearer's netns is repeatedly torn
down. The completion must run asynchronously to outlive
tipc_crypto_stop(); on x86 the stock aesni gcm(aes) now decrypts
synchronously, so the async path was exercised via cryptd offload. The
unguarded aead->crypto dereference in tipc_aead_decrypt_done() is the
unpatched upstream path; tipc_aead_decrypt() still lacks
maybe_get_net(aead->crypto->net), so the completion can outlive the free
on any config where crypto_aead_decrypt() goes async.
Found by 0sec automated security-research tooling (https://0sec.ai).Show less |
In the Linux kernel, the following vulnerability has been resolved:
pNFS: Fix use-after-free in pnfs_update_layout()
When hitting the NFS_LAYOUT_RETURN branch in pnfs_update_layout(),
the code calls pnfs_prepare_to_ret...Show moreIn the Linux kernel, the following vulnerability has been resolved:
pNFS: Fix use-after-free in pnfs_update_layout()
When hitting the NFS_LAYOUT_RETURN branch in pnfs_update_layout(),
the code calls pnfs_prepare_to_retry_layoutget(lo). If it succeeds,
pnfs_put_layout_hdr(lo) is called before trace_pnfs_update_layout(),
which still references 'lo'. This results in a use-after-free when the
tracepoint accesses lo's fields.
Fix this by moving the tracepoint call before pnfs_put_layout_hdr(lo).Show less |
In the Linux kernel, the following vulnerability has been resolved:
rpmsg: char: Fix use-after-free on probe error path
rpmsg_chrdev_probe() stores the newly allocated eptdev in the default
endpoint's priv pointer befo...Show moreIn the Linux kernel, the following vulnerability has been resolved:
rpmsg: char: Fix use-after-free on probe error path
rpmsg_chrdev_probe() stores the newly allocated eptdev in the default
endpoint's priv pointer before calling rpmsg_chrdev_eptdev_add(). If
rpmsg_chrdev_eptdev_add() then fails, its error path frees eptdev while
the default endpoint may still dispatch callbacks with the stale priv
pointer.
Avoid publishing eptdev through the default endpoint until
rpmsg_chrdev_eptdev_add() succeeds. Messages received before the priv
pointer is published should be ignored by rpmsg_ept_cb(). Flow-control
updates can hit rpmsg_ept_flow_cb() in the same window, so make both
callbacks return success when priv is NULL.Show less |