linux-stable.git/include, branch v6.12.85

crypto: algif_aead - Revert to operating out-of-place

2026-04-30T09:14:46+00:00

commit a664bf3d603dc3bdcf9ae47cc21e0daec706d7a5 upstream.

This mostly reverts commit 72548b093ee3 except for the copying of
the associated data.

There is no benefit in operating in-place in algif_aead since the
source and destination come from different mappings.  Get rid of
all the complexity added for in-place operation and just copy the
AD directly.

Fixes: 72548b093ee3 ("crypto: algif_aead - copy AAD from src to dst")
Reported-by: Taeyang Lee <0wn@theori.io>
Signed-off-by: Herbert Xu 
Signed-off-by: Eric Biggers 
Signed-off-by: Greg Kroah-Hartman

crypto: scatterwalk - Backport memcpy_sglist()

2026-04-30T09:14:46+00:00

This backports the current implementation of memcpy_sglist() from
upstream commit 4dffc9bbffb9ccfcda730d899c97c553599e7ca8.

This function was rewritten twice.  The earlier implementations had many
prerequisite commits, while the latest implementation is standalone.
It's much easier to just backport the latest code directly.

Signed-off-by: Eric Biggers 
Signed-off-by: Greg Kroah-Hartman

wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure

2026-04-27T13:24:24+00:00

[ Upstream commit d5ad6ab61cbd89afdb60881f6274f74328af3ee9 ]

ieee80211_tx_prepare_skb() has three error paths, but only two of them
free the skb. The first error path (ieee80211_tx_prepare() returning
TX_DROP) does not free it, while invoke_tx_handlers() failure and the
fragmentation check both do.

Add kfree_skb() to the first error path so all three are consistent,
and remove the now-redundant frees in callers (ath9k, mt76,
mac80211_hwsim) to avoid double-free.

Document the skb ownership guarantee in the function's kdoc.

Signed-off-by: Felix Fietkau 
Link: https://patch.msgid.link/20260314065455.2462900-1-nbd@nbd.name
Fixes: 06be6b149f7e ("mac80211: add ieee80211_tx_prepare_skb() helper function")
Signed-off-by: Johannes Berg 
[ Exclude changes to drivers/net/wireless/mediatek/mt76/scan.c as this file is first
 introduced by commit 31083e38548f("wifi: mt76: add code for emulating hardware scanning")
 after linux-6.14.]
Signed-off-by: Li hongliang <1468888505@139.com>
Signed-off-by: Sasha Levin

mm/userfaultfd: fix hugetlb fault mutex hash calculation

2026-04-27T13:24:24+00:00

[ Upstream commit 0217c7fb4de4a40cee667eb21901f3204effe5ac ]

In mfill_atomic_hugetlb(), linear_page_index() is used to calculate the
page index for hugetlb_fault_mutex_hash().  However, linear_page_index()
returns the index in PAGE_SIZE units, while hugetlb_fault_mutex_hash()
expects the index in huge page units.  This mismatch means that different
addresses within the same huge page can produce different hash values,
leading to the use of different mutexes for the same huge page.  This can
cause races between faulting threads, which can corrupt the reservation
map and trigger the BUG_ON in resv_map_release().

Fix this by introducing hugetlb_linear_page_index(), which returns the
page index in huge page granularity, and using it in place of
linear_page_index().

Link: https://lkml.kernel.org/r/20260310110526.335749-1-jianhuizzzzz@gmail.com
Fixes: a08c7193e4f1 ("mm/filemap: remove hugetlb special casing in filemap.c")
Signed-off-by: Jianhui Zhou 
Reported-by: syzbot+f525fd79634858f478e7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f525fd79634858f478e7
Acked-by: SeongJae Park 
Reviewed-by: David Hildenbrand (Arm) 
Acked-by: Mike Rapoport (Microsoft) 
Cc: Jane Chu 
Cc: Andrea Arcangeli 
Cc: Hugh Dickins 
Cc: JonasZhou 
Cc: Muchun Song 
Cc: Oscar Salvador 
Cc: Peter Xu 
Cc: SeongJae Park 
Cc: Sidhartha Kumar 
Cc: 
Signed-off-by: Andrew Morton 
[ placed new `hugetlb_linear_page_index()` before `hstate_is_gigantic()` ]
Signed-off-by: Sasha Levin

KVM: x86: Use scratch field in MMIO fragment to hold small write values

2026-04-22T11:19:02+00:00

commit 0b16e69d17d8c35c5c9d5918bf596c75a44655d3 upstream.

When exiting to userspace to service an emulated MMIO write, copy the
to-be-written value to a scratch field in the MMIO fragment if the size
of the data payload is 8 bytes or less, i.e. can fit in a single chunk,
instead of pointing the fragment directly at the source value.

This fixes a class of use-after-free bugs that occur when the emulator
initiates a write using an on-stack, local variable as the source, the
write splits a page boundary, *and* both pages are MMIO pages.  Because
KVM's ABI only allows for physically contiguous MMIO requests, accesses
that split MMIO pages are separated into two fragments, and are sent to
userspace one at a time.  When KVM attempts to complete userspace MMIO in
response to KVM_RUN after the first fragment, KVM will detect the second
fragment and generate a second userspace exit, and reference the on-stack
variable.

The issue is most visible if the second KVM_RUN is performed by a separate
task, in which case the stack of the initiating task can show up as truly
freed data.

  ==================================================================
  BUG: KASAN: use-after-free in complete_emulated_mmio+0x305/0x420
  Read of size 1 at addr ffff888009c378d1 by task syz-executor417/984

  CPU: 1 PID: 984 Comm: syz-executor417 Not tainted 5.10.0-182.0.0.95.h2627.eulerosv2r13.x86_64 #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace:
  dump_stack+0xbe/0xfd
  print_address_description.constprop.0+0x19/0x170
  __kasan_report.cold+0x6c/0x84
  kasan_report+0x3a/0x50
  check_memory_region+0xfd/0x1f0
  memcpy+0x20/0x60
  complete_emulated_mmio+0x305/0x420
  kvm_arch_vcpu_ioctl_run+0x63f/0x6d0
  kvm_vcpu_ioctl+0x413/0xb20
  __se_sys_ioctl+0x111/0x160
  do_syscall_64+0x30/0x40
  entry_SYSCALL_64_after_hwframe+0x67/0xd1
  RIP: 0033:0x42477d
  Code: <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
  RSP: 002b:00007faa8e6890e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00000000004d7338 RCX: 000000000042477d
  RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
  RBP: 00000000004d7330 R08: 00007fff28d546df R09: 0000000000000000
  R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004d733c
  R13: 0000000000000000 R14: 000000000040a200 R15: 00007fff28d54720

  The buggy address belongs to the page:
  page:0000000029f6a428 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x9c37
  flags: 0xfffffc0000000(node=0|zone=1|lastcpupid=0x1fffff)
  raw: 000fffffc0000000 0000000000000000 ffffea0000270dc8 0000000000000000
  raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected

  Memory state around the buggy address:
  ffff888009c37780: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff888009c37800: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  >ffff888009c37880: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                   ^
  ffff888009c37900: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ffff888009c37980: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
  ==================================================================

The bug can also be reproduced with a targeted KVM-Unit-Test by hacking
KVM to fill a large on-stack variable in complete_emulated_mmio(), i.e. by
overwrite the data value with garbage.

Limit the use of the scratch fields to 8-byte or smaller accesses, and to
just writes, as larger accesses and reads are not affected thanks to
implementation details in the emulator, but add a sanity check to ensure
those details don't change in the future.  Specifically, KVM never uses
on-stack variables for accesses larger that 8 bytes, e.g. uses an operand
in the emulator context, and *all* reads are buffered through the mem_read
cache.

Note!  Using the scratch field for reads is not only unnecessary, it's
also extremely difficult to handle correctly.  As above, KVM buffers all
reads through the mem_read cache, and heavily relies on that behavior when
re-emulating the instruction after a userspace MMIO read exit.  If a read
splits a page, the first page is NOT an MMIO page, and the second page IS
an MMIO page, then the MMIO fragment needs to point at _just_ the second
chunk of the destination, i.e. its position in the mem_read cache.  Taking
the "obvious" approach of copying the fragment value into the destination
when re-emulating the instruction would clobber the first chunk of the
destination, i.e. would clobber the data that was read from guest memory.

Fixes: f78146b0f923 ("KVM: Fix page-crossing MMIO")
Suggested-by: Yashu Zhang 
Reported-by: Yashu Zhang 
Closes: https://lore.kernel.org/all/369eaaa2b3c1425c85e8477066391bc7@huawei.com
Cc: stable@vger.kernel.org
Tested-by: Tom Lendacky 
Tested-by: Rick Edgecombe 
Link: https://patch.msgid.link/20260225012049.920665-2-seanjc@google.com
Signed-off-by: Sean Christopherson 
Signed-off-by: Greg Kroah-Hartman

x86: rename and clean up __copy_from_user_inatomic_nocache()

2026-04-22T11:19:02+00:00

commit 5de7bcaadf160c1716b20a263cf8f5b06f658959 upstream.

Similarly to the previous commit, this renames the somewhat confusingly
named function.  But in this case, it was at least less confusing: the
__copy_from_user_inatomic_nocache is indeed copying from user memory,
and it is indeed ok to be used in an atomic context, so it will not warn
about it.

But the previous commit also removed the NTB mis-use of the
__copy_from_user_inatomic_nocache() function, and as a result every
call-site is now _actually_ doing a real user copy.  That means that we
can now do the proper user pointer verification too.

End result: add proper address checking, remove the double underscores,
and change the "nocache" to "nontemporal" to more accurately describe
what this x86-only function actually does.  It might be worth noting
that only the target is non-temporal: the actual user accesses are
normal memory accesses.

Also worth noting is that non-x86 targets (and on older 32-bit x86 CPU's
before XMM2 in the Pentium III) we end up just falling back on a regular
user copy, so nothing can actually depend on the non-temporal semantics,
but that has always been true.

Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: Use __DECLARE_FLEX_ARRAY() for UAPI structures with VLAs

2026-04-22T11:19:01+00:00

[ Upstream commit 2619da73bb2f10d88f7e1087125c40144fdf0987 ]

Commit 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with
flexible-array members") broke the userspace API for C++.

These structures ending in VLAs are typically a *header*, which can be
followed by an arbitrary number of entries. Userspace typically creates
a larger structure with some non-zero number of entries, for example in
QEMU's kvm_arch_get_supported_msr_feature():

    struct {
        struct kvm_msrs info;
        struct kvm_msr_entry entries[1];
    } msr_data = {};

While that works in C, it fails in C++ with an error like:
 flexible array member 'kvm_msrs::entries' not at end of 'struct msr_data'

Fix this by using __DECLARE_FLEX_ARRAY() for the VLA, which uses [0]
for C++ compilation.

Fixes: 94dfc73e7cf4 ("treewide: uapi: Replace zero-length arrays with flexible-array members")
Cc: stable@vger.kernel.org
Signed-off-by: David Woodhouse 
Link: https://patch.msgid.link/3abaf6aefd6e5efeff3b860ac38421d9dec908db.camel@infradead.org
[sean: tag for stable@]
Signed-off-by: Sean Christopherson 
Signed-off-by: Sasha Levin

KVM: Remove subtle "struct kvm_stats_desc" pseudo-overlay

2026-04-22T11:19:01+00:00

[ Upstream commit da142f3d373a6ddaca0119615a8db2175ddc4121 ]

Remove KVM's internal pseudo-overlay of kvm_stats_desc, which subtly
aliases the flexible name[] in the uAPI definition with a fixed-size array
of the same name.  The unusual embedded structure results in compiler
warnings due to -Wflex-array-member-not-at-end, and also necessitates an
extra level of dereferencing in KVM.  To avoid the "overlay", define the
uAPI structure to have a fixed-size name when building for the kernel.

Opportunistically clean up the indentation for the stats macros, and
replace spaces with tabs.

No functional change intended.

Reported-by: Gustavo A. R. Silva 
Closes: https://lore.kernel.org/all/aPfNKRpLfhmhYqfP@kspp
Acked-by: Marc Zyngier 
Acked-by: Christian Borntraeger 
[..]
Acked-by: Anup Patel 
Reviewed-by: Bibo Mao 
Acked-by: Gustavo A. R. Silva 
Link: https://patch.msgid.link/20251205232655.445294-1-seanjc@google.com
Signed-off-by: Sean Christopherson 
Signed-off-by: Sasha Levin

net: sched: fix TCF_LAYER_TRANSPORT handling in tcf_get_base_ptr()

2026-04-22T11:19:01+00:00

[Upstream commit 4fe5a00ec70717a7f1002d8913ec6143582b3c8e]

syzbot reported that tcf_get_base_ptr() can be called while transport
header is not set [1].

Instead of returning a dangling pointer, return NULL.

Fix tcf_get_base_ptr() callers to handle this NULL value.

[1]
 WARNING: CPU: 1 PID: 6019 at ./include/linux/skbuff.h:3071 skb_transport_header include/linux/skbuff.h:3071 [inline]
 WARNING: CPU: 1 PID: 6019 at ./include/linux/skbuff.h:3071 tcf_get_base_ptr include/net/pkt_cls.h:539 [inline]
 WARNING: CPU: 1 PID: 6019 at ./include/linux/skbuff.h:3071 em_nbyte_match+0x2d8/0x3f0 net/sched/em_nbyte.c:43
Modules linked in:
CPU: 1 UID: 0 PID: 6019 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full)
Call Trace:
 
  tcf_em_match net/sched/ematch.c:494 [inline]
  __tcf_em_tree_match+0x1ac/0x770 net/sched/ematch.c:520
  tcf_em_tree_match include/net/pkt_cls.h:512 [inline]
  basic_classify+0x115/0x2d0 net/sched/cls_basic.c:50
  tc_classify include/net/tc_wrapper.h:197 [inline]
  __tcf_classify net/sched/cls_api.c:1764 [inline]
  tcf_classify+0x4cf/0x1140 net/sched/cls_api.c:1860
  multiq_classify net/sched/sch_multiq.c:39 [inline]
  multiq_enqueue+0xfd/0x4c0 net/sched/sch_multiq.c:66
  dev_qdisc_enqueue+0x4e/0x260 net/core/dev.c:4118
  __dev_xmit_skb net/core/dev.c:4214 [inline]
  __dev_queue_xmit+0xe83/0x3b50 net/core/dev.c:4729
  packet_snd net/packet/af_packet.c:3076 [inline]
  packet_sendmsg+0x3e33/0x5080 net/packet/af_packet.c:3108
  sock_sendmsg_nosec net/socket.c:727 [inline]
  __sock_sendmsg+0x21c/0x270 net/socket.c:742
  ____sys_sendmsg+0x505/0x830 net/socket.c:2630

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot+f3a497f02c389d86ef16@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6920855a.a70a0220.2ea503.0058.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet 
Reviewed-by: Jamal Hadi Salim 
Link: https://patch.msgid.link/20251121154100.1616228-1-edumazet@google.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Chelsy Ratnawat 
Signed-off-by: Sasha Levin

KVM: SEV: Disallow LAUNCH_FINISH if vCPUs are actively being created

2026-04-22T11:19:00+00:00

commit 624bf3440d7214b62c22d698a0a294323f331d5d upstream.

Reject LAUNCH_FINISH for SEV-ES and SNP VMs if KVM is actively creating
one or more vCPUs, as KVM needs to process and encrypt each vCPU's VMSA.
Letting userspace create vCPUs while LAUNCH_FINISH is in-progress is
"fine", at least in the current code base, as kvm_for_each_vcpu() operates
on online_vcpus, LAUNCH_FINISH (all SEV+ sub-ioctls) holds kvm->mutex, and
fully onlining a vCPU in kvm_vm_ioctl_create_vcpu() is done under
kvm->mutex.  I.e. there's no difference between an in-progress vCPU and a
vCPU that is created entirely after LAUNCH_FINISH.

However, given that concurrent LAUNCH_FINISH and vCPU creation can't
possibly work (for any reasonable definition of "work"), since userspace
can't guarantee whether a particular vCPU will be encrypted or not,
disallow the combination as a hardening measure, to reduce the probability
of introducing bugs in the future, and to avoid having to reason about the
safety of future changes related to LAUNCH_FINISH.

Cc: Jethro Beekman 
Closes: https://lore.kernel.org/all/b31f7c6e-2807-4662-bcdd-eea2c1e132fa@fortanix.com
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260310234829.2608037-5-seanjc@google.com
Signed-off-by: Sean Christopherson 
Signed-off-by: Greg Kroah-Hartman