linux-stable.git/include, branch linux-5.15.y

can: use skb hash instead of private variable in headroom

2026-08-27T12:28:22+00:00

commit d4fb6514ff8ed6912a71294e6b66a5d59ee88007 upstream.

The can_skb_priv::skbcnt variable is used to identify CAN skbs in the RX
path analogue to the skb->hash.

As the skb hash is not filled in CAN skbs move the private skbcnt value to
skb->hash and set skb->sw_hash accordingly. The skb->hash is a value used
for RPS to identify skbs. Use it as intended.

Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Oliver Hartkopp 
Link: https://patch.msgid.link/20260201-can_skb_ext-v8-1-3635d790fe8b@hartkopp.net
Signed-off-by: Paolo Abeni 
Signed-off-by: Oliver Hartkopp 
Signed-off-by: Greg Kroah-Hartman

KVM: Rename mmu_notifier_* to mmu_invalidate_*

2026-08-27T12:28:21+00:00

[ Upstream commit 20ec3ebd707c77fb9b11b37193449193d4649f33 ]

The motivation of this renaming is to make these variables and related
helper functions less mmu_notifier bound and can also be used for non
mmu_notifier based page invalidation. mmu_invalidate_* was chosen to
better describe the purpose of 'invalidating' a page that those
variables are used for.

  - mmu_notifier_seq/range_start/range_end are renamed to
    mmu_invalidate_seq/range_start/range_end.

  - mmu_notifier_retry{_hva} helper functions are renamed to
    mmu_invalidate_retry{_hva}.

  - mmu_notifier_count is renamed to mmu_invalidate_in_progress to
    avoid confusion with mn_active_invalidate_count.

  - While here, also update kvm_inc/dec_notifier_count() to
    kvm_mmu_invalidate_begin/end() to match the change for
    mmu_notifier_count.

No functional change intended.

Signed-off-by: Chao Peng 
Message-Id: <20220816125322.1110439-3-chao.p.peng@linux.intel.com>
Signed-off-by: Paolo Bonzini 
Stable-dep-of: 2abd5287f083 ("KVM: x86: Check for invalid/obsolete root *after* making MMU pages available")
Signed-off-by: Sasha Levin 
Signed-off-by: Kenta Akagi 
Signed-off-by: Greg Kroah-Hartman

net/sched: reject overly deep qdisc hierarchies

2026-08-27T12:28:19+00:00

[ Upstream commit dedd34b0f2310e28c5f6d4875cfbf4b7ed821c01 ]

Deep qdisc hierarchies can lead to excessive recursion in qdisc tree
walkers and exhaust the kernel stack. The existing loop check does not
cover the create-and-graft path, so a hierarchy can still be extended by
creating a new child qdisc below an already deep parent.

Store the hierarchy depth in struct Qdisc and update it when qdiscs are
grafted. Reject new child qdiscs once the parent is already at the maximum
allowed depth.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Suggested-by: Jamal Hadi Salim 
Reported-by: Vega 
Assisted-by: Codex:gpt-5.4
Signed-off-by: Zijie Huang 
Signed-off-by: Ren Wei 
Reviewed-by: Victor Nogueira 
Link: https://patch.msgid.link/1e9ab39597423fd5d13cfaaf52279b8ee3d9fc3c.1785434373.git.milkory@outlook.com
Acked-by: Jamal Hadi Salim 
Signed-off-by: Paolo Abeni 
[ Dropped the `extack` argument from the `notify_and_destroy()` context line to match 5.15's 6-parameter version. ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

packet: use consistent hard_header_len in non-ring send paths

2026-08-27T12:28:19+00:00

[ Upstream commit 03390aa32e669cc4ecd7d34108e2e1afc13d689d ]

packet_snd() reads dev->hard_header_len multiple times while allocating
and constructing an skb. Device reconfiguration can change this value
concurrently, for example through bonding device type changes.

For SOCK_RAW, packet_snd() can save a larger value in reserve and later
allocate headroom using a smaller value. Moving skb->data back by reserve
then places it before skb->head, and the following copy from userspace can
attempt an out-of-bounds write.

packet_sendmsg_spkt() has the same issue because it calculates its
reservation and header offset from separate reads before dropping the RCU
read lock to allocate the skb.

Add LL_RESERVED_SPACE_EX() for callers that already saved a header length.
Read hard_header_len once in packet_snd() and use it for allocation and
construction. In packet_sendmsg_spkt(), preserve the allocation-time value
through the device lookup retry.

The separate SOCK_DGRAM consistency problem between hard_header_len and
header_ops->create is not addressed here.

Fixes: b84bbaf7a6c8 ("packet: in packet_snd start writing at link layer allocation")
Cc: stable@vger.kernel.org
Signed-off-by: Qihang Tang 
Reviewed-by: Willem de Bruijn 
Link: https://patch.msgid.link/20260805125729.19220-3-q.h.hack.winter@gmail.com
Signed-off-by: Jakub Kicinski 
Stable-dep-of: 21b5953e7494 ("packet: use consistent hard_header_len in TX_RING send path")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PCI: host-generic: Fix NULL pointer dereference on 32-bit CAM systems

2026-08-27T12:28:18+00:00

commit 008cb88edb41f3c7c8e0ed763ff9f26719830984 upstream.

On 32-bit systems the config space is too large to ioremap in one go, so
pci_ecam_create() maps each bus segment separately and relies on the
->add_bus callback (pci_ecam_add_bus) to populate the per-bus mapping in
cfg->winp[]. pci_ecam_map_bus() then uses that mapping as the base for
every config access.

The generic ECAM ops (pci_generic_ecam_ops) already provide the ->add_bus
and ->remove_bus callbacks, but the CAM (legacy) ops in pci-host-generic.c
do not. As a result, on a 32-bit host using "pci-host-cam-generic" the
per-bus mapping is never set up and the first config read dereferences a
NULL base, crashing during bus enumeration:

 Unable to handle kernel NULL pointer dereference at virtual address 00000800
 Oops [#1]
 CPU: 0 PID: 1 Comm: swapper Not tainted 6.9.7+ #43
 Hardware name: Digilent Nexys-Video-A7 RV32 (DT)
 epc : pci_generic_config_read+0x40/0xb0
  ra : pci_generic_config_read+0x2c/0xb0
 [] pci_generic_config_read+0x40/0xb0
 [] pci_bus_read_config_dword+0x50/0xb0
 [] pci_bus_generic_read_dev_vendor_id+0x3c/0x1ec
 [] pci_scan_single_device+0xa4/0x11c
 [] pci_scan_slot+0x9c/0x23c
 [] pci_scan_child_bus_extend+0x58/0x2f4
 [] pci_scan_root_bus_bridge+0x64/0xe8
 [] pci_host_probe+0x20/0xc8
 [] pci_host_common_probe+0x144/0x1e4

Fix this by giving the CAM ops the same ->add_bus/->remove_bus callbacks.
Since pci_ecam_add_bus() and pci_ecam_remove_bus() are static to ecam.c,
move the CAM ops definition there as pci_generic_cam_ops (mirroring
pci_generic_ecam_ops) and export it for pci-host-generic.c to reference.

Fixes: 8fe55ef23387 ("PCI: Dynamically map ECAM regions")
Signed-off-by: Steffen Persvold 
[mani: removed timestamp from log]
Signed-off-by: Manivannan Sadhasivam 
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260709122446.3151899-1-spersvold@gmail.com
Signed-off-by: Greg Kroah-Hartman

jiffies: Cast to unsigned long in secs_to_jiffies() conversion

2026-08-23T12:17:31+00:00

commit bb2784d9ab49587ba4fbff37a319fff2924db289 upstream.

While converting users of msecs_to_jiffies(), lkp reported that some range
checks would always be true because of the mismatch between the implied int
value of secs_to_jiffies() vs the unsigned long return value of the
msecs_to_jiffies() calls it was replacing.

Fix this by casting the secs_to_jiffies() input value to unsigned long.

Fixes: b35108a51cf7ba ("jiffies: Define secs_to_jiffies()")
Reported-by: kernel test robot 
Signed-off-by: Easwar Hariharan 
Signed-off-by: Thomas Gleixner 
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20250130192701.99626-1-eahariha@linux.microsoft.com
Closes: https://lore.kernel.org/oe-kbuild-all/202501301334.NB6NszQR-lkp@intel.com/
Signed-off-by: Greg Kroah-Hartman

net: add a couple of helpers for iph tot_len

2026-08-23T12:17:30+00:00

[ Upstream commit 058a8f7f73aae1cc22b53fcefec031b9e391b54d ]

This patch adds three APIs to replace the iph->tot_len setting
and getting in all places where IPv4 BIG TCP packets may reach,
they will be used in the following patches.

Note that iph_totlen() will be used when iph is not in linear
data of the skb.

Signed-off-by: Xin Long 
Reviewed-by: David Ahern 
Reviewed-by: Eric Dumazet 
Signed-off-by: Jakub Kicinski 
Stable-dep-of: 8a7ed561671a ("net/sched: act_ct: fix sk_buff leak when the header checks reject a packet")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

jiffies: Define secs_to_jiffies()

2026-08-23T12:17:30+00:00

[ Upstream commit b35108a51cf7bab58d7eace1267d7965978bcdb8 ]

secs_to_jiffies() is defined in hci_event.c and cannot be reused by
other call sites. Hoist it into the core code to allow conversion of the
~1150 usages of msecs_to_jiffies() that either:

 - use a multiplier value of 1000 or equivalently MSEC_PER_SEC, or
 - have timeouts that are denominated in seconds (i.e. end in 000)

It's implemented as a macro to allow usage in static initializers.

This will also allow conversion of yet more sites that use (sec * HZ)
directly, and improve their readability.

Suggested-by: Michael Kelley 
Signed-off-by: Easwar Hariharan 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Luiz Augusto von Dentz 
Link: https://lore.kernel.org/all/20241030-open-coded-timeouts-v3-1-9ba123facf88@linux.microsoft.com
Stable-dep-of: c2816d613f38 ("ice: wait for reset completion in ice_resume()")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

fs: don't block write during exec on pre-content watched files

2026-08-23T12:17:29+00:00

[ Upstream commit 0357ef03c94ef835bd44a0658b8edb672a9dbf51 ]

Commit 2a010c412853 ("fs: don't block i_writecount during exec") removed
the legacy behavior of getting ETXTBSY on attempt to open and executable
file for write while it is being executed.

This commit was reverted because an application that depends on this
legacy behavior was broken by the change.

We need to allow HSM writing into executable files while executed to
fill their content on-the-fly.

To that end, disable the ETXTBSY legacy behavior for files that are
watched by pre-content events.

This change is not expected to cause regressions with existing systems
which do not have any pre-content event listeners.

Signed-off-by: Amir Goldstein 
Acked-by: Christian Brauner 
Signed-off-by: Jan Kara 
Link: https://patch.msgid.link/20241128142532.465176-1-amir73il@gmail.com
Stable-dep-of: db1856ea9196 ("binfmt_misc: restore write access when removing an entry")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

fsnotify: opt-in for permission events at file open time

2026-08-23T12:17:29+00:00

[ Upstream commit a94204f4d48e28a711b7ed10399f749286c433e3 ]

Legacy inotify/fanotify listeners can add watches for events on inode,
parent or mount and expect to get events (e.g. FS_MODIFY) on files that
were already open at the time of setting up the watches.

fanotify permission events are typically used by Anti-malware sofware,
that is watching the entire mount and it is not common to have more that
one Anti-malware engine installed on a system.

To reduce the overhead of the fsnotify_file_perm() hooks on every file
access, relax the semantics of the legacy FAN_ACCESS_PERM event to generate
events only if there were *any* permission event listeners on the
filesystem at the time that the file was opened.

The new semantic is implemented by extending the FMODE_NONOTIFY bit into
two FMODE_NONOTIFY_* bits, that are used to store a mode for which of the
events types to report.

This is going to apply to the new fanotify pre-content events in order
to reduce the cost of the new pre-content event vfs hooks.

[Thanks to Bert Karwatzki  for reporting a bug in this
code with CONFIG_FANOTIFY_ACCESS_PERMISSIONS disabled]

Suggested-by: Linus Torvalds 
Link: https://lore.kernel.org/linux-fsdevel/CAHk-=wj8L=mtcRTi=NECHMGfZQgXOp_uix1YVh04fEmrKaMnXA@mail.gmail.com/
Signed-off-by: Amir Goldstein 
Signed-off-by: Jan Kara 
Link: https://patch.msgid.link/5ea5f8e283d1edb55aa79c35187bfe344056af14.1731684329.git.josef@toxicpanda.com
Stable-dep-of: db1856ea9196 ("binfmt_misc: restore write access when removing an entry")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman