linux-stable.git/include/linux, branch v6.18.40

seqlock: fix scoped_seqlock_read kernel-doc

2026-07-24T14:17:26+00:00

commit f88a31308db6a856229150039b0f56d59696ed31 upstream.

Eliminate all kernel-doc warnings in seqlock.h:

- correct the macro to have "()" immediately following the macro name
- don't include the macro parameters in the short description (first line)
- make the parameter names in the comments match the actual macro
  parameter names.
- use "::" for the Example

WARNING: include/linux/seqlock.h:1341 This comment starts with '/**', but isn't a kernel-doc comment.
 * scoped_seqlock_read (lock, ss_state) - execute the read side critical
Documentation/locking/seqlock:242: include/linux/seqlock.h:1351: WARNING:
  Definition list ends without a blank line; unexpected unindent. [docutils]
Warning: include/linux/seqlock.h:1357 function parameter '_seqlock' not described in 'scoped_seqlock_read'
Warning: include/linux/seqlock.h:1357 function parameter '_target' not described in 'scoped_seqlock_read'

Fixes: cc39f3872c08 ("seqlock: Introduce scoped_seqlock_read()")
Signed-off-by: Randy Dunlap 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://patch.msgid.link/20260123183749.3997533-1-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman

bpf: Reject BPF_MAP_TYPE_INODE_STORAGE creation if BPF LSM is uninitialized

2026-07-24T14:17:26+00:00

[ Upstream commit a6f0643e4f63cfaa0d5d4a69de4f132eac4b8fe4 ]

When CONFIG_BPF_LSM=y is set, BPF inode storage maps
(BPF_MAP_TYPE_INODE_STORAGE) are compiled into the kernel. However,
if the BPF LSM is not explicitly enabled at boot time (e.g. omitted
from the "lsm=" boot parameter), lsm_prepare() is never executed for
the BPF LSM.

Consequently, the BPF inode security blob offset
(bpf_lsm_blob_sizes.lbs_inode) is never initialized and remains at
its default compiled size of 8 bytes instead of being updated to a
valid offset past the reserved struct rcu_head (typically 16 bytes
or more).

When a privileged user creates and updates a BPF_MAP_TYPE_INODE_STORAGE
map, bpf_inode() evaluates inode->i_security + 8. This erroneously
aliases the struct rcu_head.func callback pointer at the beginning
of the inode->i_security blob. During subsequent map element cleanup
or inode destruction, writing NULL to owner_storage clears the queued
RCU callback pointer. When rcu_do_batch() later executes the queued
callback, it attempts an instruction fetch at address 0x0, triggering
an immediate kernel panic.

Fix this by introducing a global bpf_lsm_initialized boolean flag
marked with __ro_after_init. Set this flag to true inside bpf_lsm_init()
when the LSM framework successfully registers the BPF LSM. Gate map
allocation in inode_storage_map_alloc() on this flag, returning
-EOPNOTSUPP if the BPF LSM is in turn uninitialized.

This fail-fast approach prevents userspace from allocating inode
storage maps when the supporting BPF LSM infrastructure is absent,
avoiding zombie map states.

Fixes: 8ea636848aca ("bpf: Implement bpf_local_storage for inodes")
Reported-by: oxsignal 
Signed-off-by: Matt Bobrowski 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Emil Tsalapatis 
Reviewed-by: Amery Hung 
Link: https://lore.kernel.org/bpf/20260628201103.3624525-1-mattbobrowski@google.com
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

new helper: simple_remove_by_name()

2026-07-24T14:17:24+00:00

[ Upstream commit 4051a9115ad24bb9a691774730ca9c1dd56de665 ]

simple_recursive_removal(), but instead of victim dentry it takes
parent + name.

Used to be open-coded in fs/fuse/control.c, but there's no need to expose
the guts of that thing there and there are other potential users, so
let's lift it into libfs...

Acked-by: Miklos Szeredi 
Signed-off-by: Al Viro 
Stable-dep-of: 3137b243c939 ("usb: gadget: f_fs: initialize reset_work at allocation time")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

bpf: Consistently use bpf_rcu_lock_held() everywhere

2026-07-24T14:17:23+00:00

[ Upstream commit 48a97ffc6c826640907d13b199e29008f4fe2c15 ]

We have many places which open-code what's now is bpf_rcu_lock_held()
macro, so replace all those places with a clean and short macro invocation.
For that, move bpf_rcu_lock_held() macro into include/linux/bpf.h.

Signed-off-by: Andrii Nakryiko 
Signed-off-by: Daniel Borkmann 
Acked-by: Jiri Olsa 
Link: https://lore.kernel.org/bpf/20251014201403.4104511-1-andrii@kernel.org
Stable-dep-of: 2f884d371faf ("bpf: Allow LPM map access from sleepable BPF programs")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

seqlock: Introduce scoped_seqlock_read()

2026-07-24T14:17:23+00:00

[ Upstream commit cc39f3872c0865bef992b713338df369554fa9e0 ]

The read_seqbegin/need_seqretry/done_seqretry API is cumbersome and
error prone. With the new helper the "typical" code like

	int seq, nextseq;
	unsigned long flags;

	nextseq = 0;
	do {
		seq = nextseq;
		flags = read_seqbegin_or_lock_irqsave(&seqlock, &seq);

		// read-side critical section

		nextseq = 1;
	} while (need_seqretry(&seqlock, seq));
	done_seqretry_irqrestore(&seqlock, seq, flags);

can be rewritten as

	scoped_seqlock_read (&seqlock, ss_lock_irqsave) {
		// read-side critical section
	}

Original idea by Oleg Nesterov; with contributions from Linus.

Originally-by: Oleg Nesterov 
Signed-off-by: Peter Zijlstra (Intel) 
Stable-dep-of: 6650527444da ("proc: protect ptrace_may_access() with exec_update_lock (part 1)")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PCI: Fix restoring BARs on BAR resize rollback path

2026-07-24T14:17:21+00:00

[ Upstream commit 337b1b566db087347194e4543ddfdfa5645275cc ]

BAR resize operation is implemented in the pci_resize_resource() and
pbus_reassign_bridge_resources() functions. pci_resize_resource() can be
called either from __resource_resize_store() from sysfs or directly by the
driver for the Endpoint Device.

The pci_resize_resource() requires that caller has released the device
resources that share the bridge window with the BAR to be resized as
otherwise the bridge window is pinned in place and cannot be changed.

pbus_reassign_bridge_resources() rolls back resources if the resize
operation fails, but rollback is performed only for the bridge windows.
Because releasing the device resources are done by the caller of the BAR
resize interface, these functions performing the BAR resize do not have
access to the device resources as they were before the resize.

pbus_reassign_bridge_resources() could try __pci_bridge_assign_resources()
after rolling back the bridge windows as they were, however, it will not
guarantee the resource are assigned due to differences in how FW and the
kernel assign the resources (alignment of the start address and tail).

To perform rollback robustly, the BAR resize interface has to be altered to
also release the device resources that share the bridge window with the BAR
to be resized.

Also, remove restoring from the entries failed list as saved list should
now contain both the bridge windows and device resources so the extra
restore is duplicated work.

Some drivers (currently only amdgpu) want to prevent releasing some
resources. Add exclude_bars param to pci_resize_resource() and make amdgpu
pass its register BAR (BAR 2 or 5), which should never be released during
resize operation. Normally 64-bit prefetchable resources do not share a
bridge window with the 32-bit only register BAR, but there are various
fallbacks in the resource assignment logic which may make the resources
share the bridge window in rare cases.

This change (together with the driver side changes) is to counter the
resource releases that had to be done to prevent resource tree corruption
in the ("PCI: Release assigned resource before restoring them") change. As
such, it likely restores functionality in cases where device resources were
released to avoid resource tree conflicts which appeared to be "working"
when such conflicts were not correctly detected by the kernel.

Reported-by: Simon Richter 
Link: https://lore.kernel.org/linux-pci/f9a8c975-f5d3-4dd2-988e-4371a1433a60@hogyros.de/
Reported-by: Alex Bennée 
Link: https://lore.kernel.org/linux-pci/874irqop6b.fsf@draig.linaro.org/
Signed-off-by: Ilpo Järvinen 
[bhelgaas: squash amdgpu BAR selection from
https: //lore.kernel.org/r/20251114103053.13778-1-ilpo.jarvinen@linux.intel.com]
Signed-off-by: Bjorn Helgaas 
Tested-by: Alex Bennée  # AVA, AMD GPU
Reviewed-by: Christian König 
Link: https://patch.msgid.link/20251113162628.5946-7-ilpo.jarvinen@linux.intel.com
Stable-dep-of: ee7471fe968d ("PCI: Skip Resizable BAR restore on read error")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

firmware_loader: Add cancel helper for async requests

2026-07-24T14:17:20+00:00

[ Upstream commit b9bdd68b8b979c7e9de58b2e7d21e1d7d932c755 ]

request_firmware_nowait() keeps the callback module pinned and holds
a device reference until the firmware work completes.

Callers still have no way to cancel or synchronize the queued callback
before tearing down their driver-private state.

Track scheduled async firmware work in an internal list and add
request_firmware_nowait_cancel(). The helper cancels work matching the
device, callback context and callback function. It cancels work that has
not started yet and waits for an already-running callback to return. If
the request has already completed, it is a no-op.

Keep the existing request_firmware_nowait() lifetime model manual. A
devres-managed variant can be layered on top separately if needed.

Signed-off-by: Cássio Gabriel 
Reviewed-by: Takashi Iwai 
Acked-by: Danilo Krummrich 
Signed-off-by: Takashi Iwai 
Link: https://patch.msgid.link/20260505-alsa-hda-tas2781-fw-callback-teardown-v4-1-e7c4bf930dc8@gmail.com
Stable-dep-of: 5367e2ad14f0 ("ALSA: hda/tas2781: Cancel async firmware request at unbind")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

wifi: ieee80211: validate MLE common info length

2026-07-24T14:17:18+00:00

commit 293baeae9b2434a3e432629d7720b5603db2d77e upstream.

ieee80211_mle_common_size() uses the first common-info octet as the
common information length for all known MLE types. However,
ieee80211_mle_size_ok() only validates that octet for Basic, Probe
Request, and TDLS MLEs.

Reconfiguration MLEs also skipped the length octet when calculating the
minimum common size, and Priority Access MLEs skipped validation of the
advertised common information length.

Account for the Reconfiguration common-info length octet and validate
the advertised common information length for all known MLE types. Keep
unknown-type handling unchanged.

Fixes: 0f48b8b88aa9 ("wifi: ieee80211: add definitions for multi-link element")
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Li 
Link: https://patch.msgid.link/20260611173506.36838-2-enderaoelyther@gmail.com
[remove now misleading comment]
Signed-off-by: Johannes Berg 
Signed-off-by: Greg Kroah-Hartman

SUNRPC: pin upper rpc_clnt across the TLS connect_worker

2026-07-24T14:16:50+00:00

[ Upstream commit 46bc86c833956219bbfd246c1ffd832a479c5199 ]

The TLS connect path has a use-after-free: nothing pins the
upper rpc_clnt across the delayed connect_worker. xs_connect()
stores task->tk_client in sock_xprt::clnt as a raw pointer
and queues the worker; for TLS-secured transports that worker
is xs_tcp_tls_setup_socket(), which reads several fields out
of the saved pointer (cl_timeout, cl_program, cl_prog,
cl_vers, cl_cred, cl_stats) to construct the args for the
inner handshake rpc_clnt.

The xprt does not reference the rpc_clnt; the rpc_clnt
references the xprt. xs_destroy() does cancel the
connect_worker, but it runs only when the xprt's refcount
drops to zero, which cannot happen until the rpc_clnt
releases its cl_xprt reference in rpc_free_client_work().
When a TLS handshake fails fatally (for example, an mTLS
mount whose client cert does not match the server), the
connecting task is woken with -EACCES and exits, the mount
caller invokes rpc_shutdown_client(), and the upper rpc_clnt
is freed before the queued connect_worker fires.
xs_tcp_tls_setup_socket() then dereferences the freed clnt,
producing the refcount_t underflow Michael Nemanov reported.

Take a reference on the upper rpc_clnt in xs_connect() for
TLS transports via a new rpc_hold_client() helper, and drop
it in the connect_worker's exit path with rpc_release_client().
The xprt_lock_connect() / xprt_unlock_connect() pairing
already serialises xs_connect() with xs_tcp_tls_setup_socket(),
so the take and release are balanced one-for-one.

The non-TLS connect worker (xs_tcp_setup_socket) never reads
sock_xprt::clnt, so leave that path alone and avoid the
clnt-holds-xprt-holds-clnt cycle that would otherwise prevent
xprt destruction.

Reported-by: Michael Nemanov 
Closes: https://lore.kernel.org/linux-nfs/40e3d522-dfcf-4fc1-9c55-b5e81f1536d5@vastdata.com/
Fixes: 75eb6af7acdf ("SUNRPC: Add a TCP-with-TLS RPC transport class")
Signed-off-by: Chuck Lever 
Tested-by: Michael Nemanov 
Reviewed-by: Michael Nemanov 
Signed-off-by: Anna Schumaker 
Signed-off-by: Sasha Levin

ipv4: igmp: Fix potential UAF in igmp_gq_start_timer()

2026-07-24T14:16:49+00:00

[ Upstream commit 7b19c0f81ed1fdaec6bc522569be367199a9edf3 ]

A race condition exists between device teardown (inetdev_destroy) and
incoming IGMP query processing (igmp_rcv), leading to a Use-After-Free
in the IGMP timer callback.

During device destruction, inetdev_destroy() drops the primary reference
to in_device, which can drop its refcount to 0. The actual freeing of
in_device memory is deferred via RCU (using call_rcu()).

Concurrently, igmp_rcv() runs under RCU read lock and obtains the
in_device pointer. Because the memory is RCU-protected, CPU-0 can safely
dereference in_device even if its refcount has hit 0.

However, if CPU-0 calls igmp_gq_start_timer() and re-arms the timer, it
attempts to acquire a reference using in_dev_hold(). This increments the
refcount from 0 to 1, triggering a "refcount_t: addition on 0" warning.
Since the in_device memory is still scheduled to be freed after the RCU
grace period (as the free callback does not check the refcount again),
the device is freed while the timer is still armed. When the timer
expires, it accesses the freed memory, causing a kernel panic.

Fix this by using refcount_inc_not_zero() (via a new helper
in_dev_hold_safe()) to prevent acquiring a reference if the device is
already being destroyed. If the refcount is 0, we do not arm the timer.

A similar issue in IPv6 MLD is fixed in a subsequent patch.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Zero Day Initiative 
Signed-off-by: Eric Dumazet 
Reviewed-by: Ido Schimmel 
Link: https://patch.msgid.link/20260705181756.963063-2-edumazet@google.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Sasha Levin