| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
block: RCU protect disk->conv_zones_bitmap
Ensure that a disk revalidation changing the conventional zones bitmap
of a disk does not cause invalid memory references when using the
disk_zone_is_conv() helper by RCU protecting the disk->conv_zones_bitmap
pointer.
disk_zone_is_conv() is modified to operate under the RCU read lock and
the function disk_set_conv_zones_bitmap() is added to update a disk
conv_zones_bitmap pointer using rcu_replace_pointer() with the disk
zone_wplugs_lock spinlock held.
disk_free_zone_resources() is modified to call
disk_update_zone_resources() with a NULL bitmap pointer to free the disk
conv_zones_bitmap. disk_set_conv_zones_bitmap() is also used in
disk_update_zone_resources() to set the new (revalidated) bitmap and
free the old one. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/cpum_sf: Handle CPU hotplug remove during sampling
CPU hotplug remove handling triggers the following function
call sequence:
CPUHP_AP_PERF_S390_SF_ONLINE --> s390_pmu_sf_offline_cpu()
...
CPUHP_AP_PERF_ONLINE --> perf_event_exit_cpu()
The s390 CPUMF sampling CPU hotplug handler invokes:
s390_pmu_sf_offline_cpu()
+--> cpusf_pmu_setup()
+--> setup_pmc_cpu()
+--> deallocate_buffers()
This function de-allocates all sampling data buffers (SDBs) allocated
for that CPU at event initialization. It also clears the
PMU_F_RESERVED bit. The CPU is gone and can not be sampled.
With the event still being active on the removed CPU, the CPU event
hotplug support in kernel performance subsystem triggers the
following function calls on the removed CPU:
perf_event_exit_cpu()
+--> perf_event_exit_cpu_context()
+--> __perf_event_exit_context()
+--> __perf_remove_from_context()
+--> event_sched_out()
+--> cpumsf_pmu_del()
+--> cpumsf_pmu_stop()
+--> hw_perf_event_update()
to stop and remove the event. During removal of the event, the
sampling device driver tries to read out the remaining samples from
the sample data buffers (SDBs). But they have already been freed
(and may have been re-assigned). This may lead to a use after free
situation in which case the samples are most likely invalid. In the
best case the memory has not been reassigned and still contains
valid data.
Remedy this situation and check if the CPU is still in reserved
state (bit PMU_F_RESERVED set). In this case the SDBs have not been
released an contain valid data. This is always the case when
the event is removed (and no CPU hotplug off occured).
If the PMU_F_RESERVED bit is not set, the SDB buffers are gone. |
| In the Linux kernel, the following vulnerability has been resolved:
virt: tdx-guest: Just leak decrypted memory on unrecoverable errors
In CoCo VMs it is possible for the untrusted host to cause
set_memory_decrypted() to fail such that an error is returned
and the resulting memory is shared. Callers need to take care
to handle these errors to avoid returning decrypted (shared)
memory to the page allocator, which could lead to functional
or security issues.
Leak the decrypted memory when set_memory_decrypted() fails,
and don't need to print an error since set_memory_decrypted()
will call WARN_ONCE(). |
| In the Linux kernel, the following vulnerability has been resolved:
net/smc: check return value of sock_recvmsg when draining clc data
When receiving clc msg, the field length in smc_clc_msg_hdr indicates the
length of msg should be received from network and the value should not be
fully trusted as it is from the network. Once the value of length exceeds
the value of buflen in function smc_clc_wait_msg it may run into deadloop
when trying to drain the remaining data exceeding buflen.
This patch checks the return value of sock_recvmsg when draining data in
case of deadloop in draining. |
| In the Linux kernel, the following vulnerability has been resolved:
crypto: bcm - add error check in the ahash_hmac_init function
The ahash_init functions may return fails. The ahash_hmac_init should
not return ok when ahash_init returns error. For an example, ahash_init
will return -ENOMEM when allocation memory is error. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf, sockmap: Fix race between element replace and close()
Element replace (with a socket different from the one stored) may race
with socket's close() link popping & unlinking. __sock_map_delete()
unconditionally unrefs the (wrong) element:
// set map[0] = s0
map_update_elem(map, 0, s0)
// drop fd of s0
close(s0)
sock_map_close()
lock_sock(sk) (s0!)
sock_map_remove_links(sk)
link = sk_psock_link_pop()
sock_map_unlink(sk, link)
sock_map_delete_from_link
// replace map[0] with s1
map_update_elem(map, 0, s1)
sock_map_update_elem
(s1!) lock_sock(sk)
sock_map_update_common
psock = sk_psock(sk)
spin_lock(&stab->lock)
osk = stab->sks[idx]
sock_map_add_link(..., &stab->sks[idx])
sock_map_unref(osk, &stab->sks[idx])
psock = sk_psock(osk)
sk_psock_put(sk, psock)
if (refcount_dec_and_test(&psock))
sk_psock_drop(sk, psock)
spin_unlock(&stab->lock)
unlock_sock(sk)
__sock_map_delete
spin_lock(&stab->lock)
sk = *psk // s1 replaced s0; sk == s1
if (!sk_test || sk_test == sk) // sk_test (s0) != sk (s1); no branch
sk = xchg(psk, NULL)
if (sk)
sock_map_unref(sk, psk) // unref s1; sks[idx] will dangle
psock = sk_psock(sk)
sk_psock_put(sk, psock)
if (refcount_dec_and_test())
sk_psock_drop(sk, psock)
spin_unlock(&stab->lock)
release_sock(sk)
Then close(map) enqueues bpf_map_free_deferred, which finally calls
sock_map_free(). This results in some refcount_t warnings along with
a KASAN splat [1].
Fix __sock_map_delete(), do not allow sock_map_unref() on elements that
may have been replaced.
[1]:
BUG: KASAN: slab-use-after-free in sock_map_free+0x10e/0x330
Write of size 4 at addr ffff88811f5b9100 by task kworker/u64:12/1063
CPU: 14 UID: 0 PID: 1063 Comm: kworker/u64:12 Not tainted 6.12.0+ #125
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Arch Linux 1.16.3-1-1 04/01/2014
Workqueue: events_unbound bpf_map_free_deferred
Call Trace:
<TASK>
dump_stack_lvl+0x68/0x90
print_report+0x174/0x4f6
kasan_report+0xb9/0x190
kasan_check_range+0x10f/0x1e0
sock_map_free+0x10e/0x330
bpf_map_free_deferred+0x173/0x320
process_one_work+0x846/0x1420
worker_thread+0x5b3/0xf80
kthread+0x29e/0x360
ret_from_fork+0x2d/0x70
ret_from_fork_asm+0x1a/0x30
</TASK>
Allocated by task 1202:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x10/0x30
__kasan_slab_alloc+0x85/0x90
kmem_cache_alloc_noprof+0x131/0x450
sk_prot_alloc+0x5b/0x220
sk_alloc+0x2c/0x870
unix_create1+0x88/0x8a0
unix_create+0xc5/0x180
__sock_create+0x241/0x650
__sys_socketpair+0x1ce/0x420
__x64_sys_socketpair+0x92/0x100
do_syscall_64+0x93/0x180
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Freed by task 46:
kasan_save_stack+0x1e/0x40
kasan_save_track+0x10/0x30
kasan_save_free_info+0x37/0x60
__kasan_slab_free+0x4b/0x70
kmem_cache_free+0x1a1/0x590
__sk_destruct+0x388/0x5a0
sk_psock_destroy+0x73e/0xa50
process_one_work+0x846/0x1420
worker_thread+0x5b3/0xf80
kthread+0x29e/0x360
ret_from_fork+0x2d/0x70
ret_from_fork_asm+0x1a/0x30
The bu
---truncated--- |
| In the Linux kernel, the following vulnerability has been resolved:
net/ipv6: release expired exception dst cached in socket
Dst objects get leaked in ip6_negative_advice() when this function is
executed for an expired IPv6 route located in the exception table. There
are several conditions that must be fulfilled for the leak to occur:
* an ICMPv6 packet indicating a change of the MTU for the path is received,
resulting in an exception dst being created
* a TCP connection that uses the exception dst for routing packets must
start timing out so that TCP begins retransmissions
* after the exception dst expires, the FIB6 garbage collector must not run
before TCP executes ip6_negative_advice() for the expired exception dst
When TCP executes ip6_negative_advice() for an exception dst that has
expired and if no other socket holds a reference to the exception dst, the
refcount of the exception dst is 2, which corresponds to the increment
made by dst_init() and the increment made by the TCP socket for which the
connection is timing out. The refcount made by the socket is never
released. The refcount of the dst is decremented in sk_dst_reset() but
that decrement is counteracted by a dst_hold() intentionally placed just
before the sk_dst_reset() in ip6_negative_advice(). After
ip6_negative_advice() has finished, there is no other object tied to the
dst. The socket lost its reference stored in sk_dst_cache and the dst is
no longer in the exception table. The exception dst becomes a leaked
object.
As a result of this dst leak, an unbalanced refcount is reported for the
loopback device of a net namespace being destroyed under kernels that do
not contain e5f80fcf869a ("ipv6: give an IPv6 dev to blackhole_netdev"):
unregister_netdevice: waiting for lo to become free. Usage count = 2
Fix the dst leak by removing the dst_hold() in ip6_negative_advice(). The
patch that introduced the dst_hold() in ip6_negative_advice() was
92f1655aa2b22 ("net: fix __dst_negative_advice() race"). But 92f1655aa2b22
merely refactored the code with regards to the dst refcount so the issue
was present even before 92f1655aa2b22. The bug was introduced in
54c1a859efd9f ("ipv6: Don't drop cache route entry unless timer actually
expired.") where the expired cached route is deleted and the sk_dst_cache
member of the socket is set to NULL by calling dst_negative_advice() but
the refcount belonging to the socket is left unbalanced.
The IPv4 version - ipv4_negative_advice() - is not affected by this bug.
When the TCP connection times out ipv4_negative_advice() merely resets the
sk_dst_cache of the socket while decrementing the refcount of the
exception dst. |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: Hold module reference while requesting a module
User space may unload ip_set.ko while it is itself requesting a set type
backend module, leading to a kernel crash. The race condition may be
provoked by inserting an mdelay() right after the nfnl_unlock() call. |
| In the Linux kernel, the following vulnerability has been resolved:
iommufd: Fix out_fput in iommufd_fault_alloc()
As fput() calls the file->f_op->release op, where fault obj and ictx are
getting released, there is no need to release these two after fput() one
more time, which would result in imbalanced refcounts:
refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 48 PID: 2369 at lib/refcount.c:31 refcount_warn_saturate+0x60/0x230
Call trace:
refcount_warn_saturate+0x60/0x230 (P)
refcount_warn_saturate+0x60/0x230 (L)
iommufd_fault_fops_release+0x9c/0xe0 [iommufd]
...
VFS: Close: file count is 0 (f_op=iommufd_fops [iommufd])
WARNING: CPU: 48 PID: 2369 at fs/open.c:1507 filp_flush+0x3c/0xf0
Call trace:
filp_flush+0x3c/0xf0 (P)
filp_flush+0x3c/0xf0 (L)
__arm64_sys_close+0x34/0x98
...
imbalanced put on file reference count
WARNING: CPU: 48 PID: 2369 at fs/file.c:74 __file_ref_put+0x100/0x138
Call trace:
__file_ref_put+0x100/0x138 (P)
__file_ref_put+0x100/0x138 (L)
__fput_sync+0x4c/0xd0
Drop those two lines to fix the warnings above. |
| In the Linux kernel, the following vulnerability has been resolved:
cachefiles: Fix NULL pointer dereference in object->file
At present, the object->file has the NULL pointer dereference problem in
ondemand-mode. The root cause is that the allocated fd and object->file
lifetime are inconsistent, and the user-space invocation to anon_fd uses
object->file. Following is the process that triggers the issue:
[write fd] [umount]
cachefiles_ondemand_fd_write_iter
fscache_cookie_state_machine
cachefiles_withdraw_cookie
if (!file) return -ENOBUFS
cachefiles_clean_up_object
cachefiles_unmark_inode_in_use
fput(object->file)
object->file = NULL
// file NULL pointer dereference!
__cachefiles_write(..., file, ...)
Fix this issue by add an additional reference count to the object->file
before write/llseek, and decrement after it finished. |
| In the Linux kernel, the following vulnerability has been resolved:
bnxt_en: Fix receive ring space parameters when XDP is active
The MTU setting at the time an XDP multi-buffer is attached
determines whether the aggregation ring will be used and the
rx_skb_func handler. This is done in bnxt_set_rx_skb_mode().
If the MTU is later changed, the aggregation ring setting may need
to be changed and it may become out-of-sync with the settings
initially done in bnxt_set_rx_skb_mode(). This may result in
random memory corruption and crashes as the HW may DMA data larger
than the allocated buffer size, such as:
BUG: kernel NULL pointer dereference, address: 00000000000003c0
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 17 PID: 0 Comm: swapper/17 Kdump: loaded Tainted: G S OE 6.1.0-226bf9805506 #1
Hardware name: Wiwynn Delta Lake PVT BZA.02601.0150/Delta Lake-Class1, BIOS F0E_3A12 08/26/2021
RIP: 0010:bnxt_rx_pkt+0xe97/0x1ae0 [bnxt_en]
Code: 8b 95 70 ff ff ff 4c 8b 9d 48 ff ff ff 66 41 89 87 b4 00 00 00 e9 0b f7 ff ff 0f b7 43 0a 49 8b 95 a8 04 00 00 25 ff 0f 00 00 <0f> b7 14 42 48 c1 e2 06 49 03 95 a0 04 00 00 0f b6 42 33f
RSP: 0018:ffffa19f40cc0d18 EFLAGS: 00010202
RAX: 00000000000001e0 RBX: ffff8e2c805c6100 RCX: 00000000000007ff
RDX: 0000000000000000 RSI: ffff8e2c271ab990 RDI: ffff8e2c84f12380
RBP: ffffa19f40cc0e48 R08: 000000000001000d R09: 974ea2fcddfa4cbf
R10: 0000000000000000 R11: ffffa19f40cc0ff8 R12: ffff8e2c94b58980
R13: ffff8e2c952d6600 R14: 0000000000000016 R15: ffff8e2c271ab990
FS: 0000000000000000(0000) GS:ffff8e3b3f840000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000003c0 CR3: 0000000e8580a004 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<IRQ>
__bnxt_poll_work+0x1c2/0x3e0 [bnxt_en]
To address the issue, we now call bnxt_set_rx_skb_mode() within
bnxt_change_mtu() to properly set the AGG rings configuration and
update rx_skb_func based on the new MTU value.
Additionally, BNXT_FLAG_NO_AGG_RINGS is cleared at the beginning of
bnxt_set_rx_skb_mode() to make sure it gets set or cleared based on
the current MTU. |
| In the Linux kernel, the following vulnerability has been resolved:
nfs/blocklayout: Don't attempt unregister for invalid block device
Since commit d869da91cccb ("nfs/blocklayout: Fix premature PR key
unregistration") an unmount of a pNFS SCSI layout-enabled NFS may
dereference a NULL block_device in:
bl_unregister_scsi+0x16/0xe0 [blocklayoutdriver]
bl_free_device+0x70/0x80 [blocklayoutdriver]
bl_free_deviceid_node+0x12/0x30 [blocklayoutdriver]
nfs4_put_deviceid_node+0x60/0xc0 [nfsv4]
nfs4_deviceid_purge_client+0x132/0x190 [nfsv4]
unset_pnfs_layoutdriver+0x59/0x60 [nfsv4]
nfs4_destroy_server+0x36/0x70 [nfsv4]
nfs_free_server+0x23/0xe0 [nfs]
deactivate_locked_super+0x30/0xb0
cleanup_mnt+0xba/0x150
task_work_run+0x59/0x90
syscall_exit_to_user_mode+0x217/0x220
do_syscall_64+0x8e/0x160
This happens because even though we were able to create the
nfs4_deviceid_node, the lookup for the device was unable to attach the
block device to the pnfs_block_dev.
If we never found a block device to register, we can avoid this case with
the PNFS_BDEV_REGISTERED flag. Move the deref behind the test for the
flag. |
| In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_event: Align BR/EDR JUST_WORKS paring with LE
This aligned BR/EDR JUST_WORKS method with LE which since 92516cd97fd4
("Bluetooth: Always request for user confirmation for Just Works")
always request user confirmation with confirm_hint set since the
likes of bluetoothd have dedicated policy around JUST_WORKS method
(e.g. main.conf:JustWorksRepairing).
CVE: CVE-2024-8805 |
| In the Linux kernel, the following vulnerability has been resolved:
netfilter: ipset: add missing range check in bitmap_ip_uadt
When tb[IPSET_ATTR_IP_TO] is not present but tb[IPSET_ATTR_CIDR] exists,
the values of ip and ip_to are slightly swapped. Therefore, the range check
for ip should be done later, but this part is missing and it seems that the
vulnerability occurs.
So we should add missing range checks and remove unnecessary range checks. |
| In the Linux kernel, the following vulnerability has been resolved:
netlink: terminate outstanding dump on socket close
Netlink supports iterative dumping of data. It provides the families
the following ops:
- start - (optional) kicks off the dumping process
- dump - actual dump helper, keeps getting called until it returns 0
- done - (optional) pairs with .start, can be used for cleanup
The whole process is asynchronous and the repeated calls to .dump
don't actually happen in a tight loop, but rather are triggered
in response to recvmsg() on the socket.
This gives the user full control over the dump, but also means that
the user can close the socket without getting to the end of the dump.
To make sure .start is always paired with .done we check if there
is an ongoing dump before freeing the socket, and if so call .done.
The complication is that sockets can get freed from BH and .done
is allowed to sleep. So we use a workqueue to defer the call, when
needed.
Unfortunately this does not work correctly. What we defer is not
the cleanup but rather releasing a reference on the socket.
We have no guarantee that we own the last reference, if someone
else holds the socket they may release it in BH and we're back
to square one.
The whole dance, however, appears to be unnecessary. Only the user
can interact with dumps, so we can clean up when socket is closed.
And close always happens in process context. Some async code may
still access the socket after close, queue notification skbs to it etc.
but no dumps can start, end or otherwise make progress.
Delete the workqueue and flush the dump state directly from the release
handler. Note that further cleanup is possible in -next, for instance
we now always call .done before releasing the main module reference,
so dump doesn't have to take a reference of its own. |
| In the Linux kernel, the following vulnerability has been resolved:
net/mlx5e: kTLS, Fix incorrect page refcounting
The kTLS tx handling code is using a mix of get_page() and
page_ref_inc() APIs to increment the page reference. But on the release
path (mlx5e_ktls_tx_handle_resync_dump_comp()), only put_page() is used.
This is an issue when using pages from large folios: the get_page()
references are stored on the folio page while the page_ref_inc()
references are stored directly in the given page. On release the folio
page will be dereferenced too many times.
This was found while doing kTLS testing with sendfile() + ZC when the
served file was read from NFS on a kernel with NFS large folios support
(commit 49b29a573da8 ("nfs: add support for large folios")). |
| In the Linux kernel, the following vulnerability has been resolved:
KVM: VMX: Bury Intel PT virtualization (guest/host mode) behind CONFIG_BROKEN
Hide KVM's pt_mode module param behind CONFIG_BROKEN, i.e. disable support
for virtualizing Intel PT via guest/host mode unless BROKEN=y. There are
myriad bugs in the implementation, some of which are fatal to the guest,
and others which put the stability and health of the host at risk.
For guest fatalities, the most glaring issue is that KVM fails to ensure
tracing is disabled, and *stays* disabled prior to VM-Enter, which is
necessary as hardware disallows loading (the guest's) RTIT_CTL if tracing
is enabled (enforced via a VMX consistency check). Per the SDM:
If the logical processor is operating with Intel PT enabled (if
IA32_RTIT_CTL.TraceEn = 1) at the time of VM entry, the "load
IA32_RTIT_CTL" VM-entry control must be 0.
On the host side, KVM doesn't validate the guest CPUID configuration
provided by userspace, and even worse, uses the guest configuration to
decide what MSRs to save/load at VM-Enter and VM-Exit. E.g. configuring
guest CPUID to enumerate more address ranges than are supported in hardware
will result in KVM trying to passthrough, save, and load non-existent MSRs,
which generates a variety of WARNs, ToPA ERRORs in the host, a potential
deadlock, etc. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: sync_linked_regs() must preserve subreg_def
Range propagation must not affect subreg_def marks, otherwise the
following example is rewritten by verifier incorrectly when
BPF_F_TEST_RND_HI32 flag is set:
0: call bpf_ktime_get_ns call bpf_ktime_get_ns
1: r0 &= 0x7fffffff after verifier r0 &= 0x7fffffff
2: w1 = w0 rewrites w1 = w0
3: if w0 < 10 goto +0 --------------> r11 = 0x2f5674a6 (r)
4: r1 >>= 32 r11 <<= 32 (r)
5: r0 = r1 r1 |= r11 (r)
6: exit; if w0 < 0xa goto pc+0
r1 >>= 32
r0 = r1
exit
(or zero extension of w1 at (2) is missing for architectures that
require zero extension for upper register half).
The following happens w/o this patch:
- r0 is marked as not a subreg at (0);
- w1 is marked as subreg at (2);
- w1 subreg_def is overridden at (3) by copy_register_state();
- w1 is read at (5) but mark_insn_zext() does not mark (2)
for zero extension, because w1 subreg_def is not set;
- because of BPF_F_TEST_RND_HI32 flag verifier inserts random
value for hi32 bits of (2) (marked (r));
- this random value is read at (5). |
| In the Linux kernel, the following vulnerability has been resolved:
mptcp: cope racing subflow creation in mptcp_rcv_space_adjust
Additional active subflows - i.e. created by the in kernel path
manager - are included into the subflow list before starting the
3whs.
A racing recvmsg() spooling data received on an already established
subflow would unconditionally call tcp_cleanup_rbuf() on all the
current subflows, potentially hitting a divide by zero error on
the newly created ones.
Explicitly check that the subflow is in a suitable state before
invoking tcp_cleanup_rbuf(). |
| In the Linux kernel, the following vulnerability has been resolved:
arm64/sve: Discard stale CPU state when handling SVE traps
The logic for handling SVE traps manipulates saved FPSIMD/SVE state
incorrectly, and a race with preemption can result in a task having
TIF_SVE set and TIF_FOREIGN_FPSTATE clear even though the live CPU state
is stale (e.g. with SVE traps enabled). This has been observed to result
in warnings from do_sve_acc() where SVE traps are not expected while
TIF_SVE is set:
| if (test_and_set_thread_flag(TIF_SVE))
| WARN_ON(1); /* SVE access shouldn't have trapped */
Warnings of this form have been reported intermittently, e.g.
https://lore.kernel.org/linux-arm-kernel/CA+G9fYtEGe_DhY2Ms7+L7NKsLYUomGsgqpdBj+QwDLeSg=JhGg@mail.gmail.com/
https://lore.kernel.org/linux-arm-kernel/000000000000511e9a060ce5a45c@google.com/
The race can occur when the SVE trap handler is preempted before and
after manipulating the saved FPSIMD/SVE state, starting and ending on
the same CPU, e.g.
| void do_sve_acc(unsigned long esr, struct pt_regs *regs)
| {
| // Trap on CPU 0 with TIF_SVE clear, SVE traps enabled
| // task->fpsimd_cpu is 0.
| // per_cpu_ptr(&fpsimd_last_state, 0) is task.
|
| ...
|
| // Preempted; migrated from CPU 0 to CPU 1.
| // TIF_FOREIGN_FPSTATE is set.
|
| get_cpu_fpsimd_context();
|
| if (test_and_set_thread_flag(TIF_SVE))
| WARN_ON(1); /* SVE access shouldn't have trapped */
|
| sve_init_regs() {
| if (!test_thread_flag(TIF_FOREIGN_FPSTATE)) {
| ...
| } else {
| fpsimd_to_sve(current);
| current->thread.fp_type = FP_STATE_SVE;
| }
| }
|
| put_cpu_fpsimd_context();
|
| // Preempted; migrated from CPU 1 to CPU 0.
| // task->fpsimd_cpu is still 0
| // If per_cpu_ptr(&fpsimd_last_state, 0) is still task then:
| // - Stale HW state is reused (with SVE traps enabled)
| // - TIF_FOREIGN_FPSTATE is cleared
| // - A return to userspace skips HW state restore
| }
Fix the case where the state is not live and TIF_FOREIGN_FPSTATE is set
by calling fpsimd_flush_task_state() to detach from the saved CPU
state. This ensures that a subsequent context switch will not reuse the
stale CPU state, and will instead set TIF_FOREIGN_FPSTATE, forcing the
new state to be reloaded from memory prior to a return to userspace. |
