[ Upstream commit 674e2b24791cbe8fd5dc8a0aed4cb4404fcd2028 ]

This command:
    # echo foo/bar >/proc/$$/attr/smack/current

gives the task a label 'foo' w/o indication
that label does not match input.
Setting the label with lsm_set_self_attr() syscall
behaves identically.

This occures because:

1) smk_parse_smack() is used to convert input to a label
2) smk_parse_smack() takes only that part from the
   beginning of the input that looks like a label.
3) `/' is prohibited in labels, so only "foo" is taken.

(2) is by design, because smk_parse_smack() is used
for parsing strings which are more than just a label.

Silent failure is not a good thing, and there are two
indicators that this was not done intentionally:

    (size >= SMK_LONGLABEL) ~> invalid

clause at the beginning of the do_setattr() and the
"Returns the length of the smack label" claim
in the do_setattr() description.

So I fixed this by adding one tiny check:
the taken label length == input length.

Since input length is now strictly controlled,
I changed the two ways of setting label

   smack_setselfattr(): lsm_set_self_attr() syscall
   smack_setprocattr(): > /proc/.../current

to accommodate the divergence in
what they understand by "input length":

  smack_setselfattr counts mandatory \0 into input length,
  smack_setprocattr does not.

  smack_setprocattr allows various trailers after label

Related changes:

* fixed description for smk_parse_smack

* allow unprivileged tasks validate label syntax.

* extract smk_parse_label_len() from smk_parse_smack()
  so parsing may be done w/o string allocation.

* extract smk_import_valid_label() from smk_import_entry()
  to avoid repeated parsing.

* smk_parse_smack(): scan null-terminated strings
  for no more than SMK_LONGLABEL(256) characters

* smack_setselfattr(): require struct lsm_ctx . flags == 0
  to reserve them for future.

Fixes: e114e473771c ("Smack: Simplified Mandatory Access Control Kernel")
Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 78fc6a94be252b27bb73e4926eed70b5e302a8e0 ]

According to [1], the label of a UNIX domain socket (UDS)
file (i.e., the filesystem object representing the socket)
is not supposed to participate in Smack security.

To achieve this, [1] labels UDS files with "*"
in smack_d_instantiate().

Before [2], smack_d_instantiate() was responsible
for initializing Smack security for all inodes,
except ones under /proc

[2] imposed the sole responsibility for initializing
inode security for newly created filesystem objects
on smack_inode_init_security().

However, smack_inode_init_security() lacks some logic
present in smack_d_instantiate().
In particular, it does not label UDS files with "*".

This patch adds the missing labeling of UDS files
with "*" to smack_inode_init_security().

Labeling UDS files with "*" in smack_d_instantiate()
still works for stale UDS files that already exist on
disk. Stale UDS files are useless, but I keep labeling
them for consistency and maybe to make easier for user
to delete them.

Compared to [1], this version introduces the following
improvements:

  * UDS file label is held inside inode only
    and not saved to xattrs.

  * relabeling UDS files (setxattr, removexattr, etc.)
    is blocked.

[1] 2010-11-24 Casey Schaufler
commit b4e0d5f0791b ("Smack: UDS revision")

[2] 2023-11-16 roberto.sassu
Fixes: e63d86b8b764 ("smack: Initialize the in-memory inode in smack_inode_init_security()")
Link: https://lore.kernel.org/linux-security-module/20231116090125.187209-5-roberto.sassu@huaweicloud.com/

Signed-off-by: Konstantin Andreev <andreev@swemel.ru>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 5799d5d8a6c877f03ad5b5a640977053be45059a ]

Use attack vector controls to select whether VMSCAPE requires mitigation,
similar to other bugs.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 278033a225e13ec21900f0a92b8351658f5377f2 ]

When CONFIG_TMPFS is enabled, the initial root filesystem is a tmpfs.
By default, a tmpfs mount is limited to using 50% of the available RAM
for its content. This can be problematic in memory-constrained
environments, particularly during a kdump capture.

In a kdump scenario, the capture kernel boots with a limited amount of
memory specified by the 'crashkernel' parameter. If the initramfs is
large, it may fail to unpack into the tmpfs rootfs due to insufficient
space. This is because to get X MB of usable space in tmpfs, 2*X MB of
memory must be available for the mount. This leads to an OOM failure
during the early boot process, preventing a successful crash dump.

This patch introduces a new kernel command-line parameter,
initramfs_options, which allows passing specific mount options directly
to the rootfs when it is first mounted. This gives users control over
the rootfs behavior.

For example, a user can now specify initramfs_options=size=75% to allow
the tmpfs to use up to 75% of the available memory. This can
significantly reduce the memory pressure for kdump.

Consider a practical example:

To unpack a 48MB initramfs, the tmpfs needs 48MB of usable space. With
the default 50% limit, this requires a memory pool of 96MB to be
available for the tmpfs mount. The total memory requirement is therefore
approximately: 16MB (vmlinuz) + 48MB (loaded initramfs) + 48MB (unpacked
kernel) + 96MB (for tmpfs) + 12MB (runtime overhead) ≈ 220MB.

By using initramfs_options=size=75%, the memory pool required for the
48MB tmpfs is reduced to 48MB / 0.75 = 64MB. This reduces the total
memory requirement by 32MB (96MB - 64MB), allowing the kdump to succeed
with a smaller crashkernel size, such as 192MB.

An alternative approach of reusing the existing rootflags parameter was
considered. However, a new, dedicated initramfs_options parameter was
chosen to avoid altering the current behavior of rootflags (which
applies to the final root filesystem) and to prevent any potential
regressions.

Also add documentation for the new kernel parameter "initramfs_options"

This approach is inspired by prior discussions and patches on the topic.
Ref: https://www.lightofdawn.org/blog/?viewDetailed=00128
Ref: https://landley.net/notes-2015.html#01-01-2015
Ref: https://lkml.org/lkml/2021/6/29/783
Ref: https://www.kernel.org/doc/html/latest/filesystems/ramfs-rootfs-initramfs.html#what-is-rootfs

Signed-off-by: Lichen Liu <lichliu@redhat.com>
Link: https://lore.kernel.org/20250815121459.3391223-1-lichliu@redhat.com
Tested-by: Rob Landley <rob@landley.net>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Pull x86 platform driver fixes from Ilpo Järvinen:
 "Fixes and New HW Supoort

   - amd/pmc: Use 8042 quirk for Stellaris Slim Gen6 AMD

   - dell: Set USTT mode according to BIOS after reboot

   - dell-lis3lv02d: Add Latitude E6530

   - lg-laptop: Fix setting the fan mode"

* tag 'platform-drivers-x86-v6.17-5' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: lg-laptop: Fix WMAB call in fan_mode_store()
  platform/x86: dell-lis3lv02d: Add Latitude E6530
  platform/x86/dell: Set USTT mode according to BIOS after reboot
  platform/x86/amd/pmc: Add Stellaris Slim Gen6 AMD to spurious 8042 quirks list

When WMAB is called to set the fan mode, the new mode is read from either
bits 0-1 or bits 4-5 (depending on the value of some other EC register).
Thus when WMAB is called with bits 4-5 zeroed and called again with
bits 0-1 zeroed, the second call undoes the effect of the first call.
This causes writes to /sys/devices/platform/lg-laptop/fan_mode to have
no effect (and causes reads to always report a status of zero).

Fix this by calling WMAB once, with the mode set in bits 0,1 and 4,5.
When the fan mode is returned from WMAB it always has this form, so
there is no need to preserve the other bits.  As a bonus, the driver
now supports the "Performance" fan mode seen in the LG-provided Windows
control app, which provides less aggressive CPU throttling but louder
fan noise and shorter battery life.

Also, correct the documentation to reflect that 0 corresponds to the
default mode (what the Windows app calls "Optimal") and 1 corresponds
to the silent mode.

Fixes: dbf0c5a6b1f8 ("platform/x86: Add LG Gram laptop special features driver")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=204913#c4
Signed-off-by: Daniel Lee <dany97@live.ca>
Link: https://patch.msgid.link/MN2PR06MB55989CB10E91C8DA00EE868DDC1CA@MN2PR06MB5598.namprd06.prod.outlook.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

Pull vmescape mitigation fixes from Dave Hansen:
 "Mitigate vmscape issue with indirect branch predictor flushes.

  vmscape is a vulnerability that essentially takes Spectre-v2 and
  attacks host userspace from a guest. It particularly affects
  hypervisors like QEMU.

  Even if a hypervisor may not have any sensitive data like disk
  encryption keys, guest-userspace may be able to attack the
  guest-kernel using the hypervisor as a confused deputy.

  There are many ways to mitigate vmscape using the existing Spectre-v2
  defenses like IBRS variants or the IBPB flushes. This series focuses
  solely on IBPB because it works universally across vendors and all
  vulnerable processors. Further work doing vendor and model-specific
  optimizations can build on top of this if needed / wanted.

  Do the normal issue mitigation dance:

   - Add the CPU bug boilerplate

   - Add a list of vulnerable CPUs

   - Use IBPB to flush the branch predictors after running guests"

* tag 'vmscape-for-linus-20250904' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/vmscape: Add old Intel CPUs to affected list
  x86/vmscape: Warn when STIBP is disabled with SMT
  x86/bugs: Move cpu_bugs_smt_update() down
  x86/vmscape: Enable the mitigation
  x86/vmscape: Add conditional IBPB mitigation
  x86/vmscape: Enumerate VMSCAPE bug
  Documentation/hw-vuln: Add VMSCAPE documentation

Attack vector controls for SSB were missed in the initial attack vector series.
The default mitigation for SSB requires user-space opt-in so it is only
relevant for user->user attacks.  Check with attack vector controls when
the command is auto - i.e., no explicit user selection has been done.

Fixes: 2d31d2874663 ("x86/bugs: Define attack vectors relevant for each bug")
Signed-off-by: David Kaplan <david.kaplan@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250819192200.2003074-5-david.kaplan@amd.com

Pull cgroup fixes from Tejun Heo:

 - Fix NULL de-ref in css_rstat_exit() which could happen after
   allocation failure

 - Fix a cpuset partition handling bug and a couple other misc issues

 - Doc spelling fix

* tag 'cgroup-for-6.17-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  docs: cgroup: fixed spelling mistakes in documentation
  cgroup: avoid null de-ref in css_rstat_exit()
  cgroup/cpuset: Remove the unnecessary css_get/put() in cpuset_partition_write()
  cgroup/cpuset: Fix a partition error with CPU hotplug
  cgroup/cpuset: Use static_branch_enable_cpuslocked() on cpusets_insane_config_key

Pull x86 fixes from Borislav Petkov:

 - Remove a transitional asm/cpuid.h header which was added only as a
   fallback during cpuid helpers reorg

 - Initialize reserved fields in the SVSM page validation calls
   structure to zero in order to allow for future structure extensions

 - Have the sev-guest driver's buffers used in encryption operations be
   in linear mapping space as the encryption operation can be offloaded
   to an accelerator

 - Have a read-only MSR write when in an AMD SNP guest trap to the
   hypervisor as it is usually done. This makes the guest user
   experience better by simply raising a #GP instead of terminating said
   guest

 - Do not output AVX512 elapsed time for kernel threads because the data
   is wrong and fix a NULL pointer dereferencing in the process

 - Adjust the SRSO mitigation selection to the new attack vectors

* tag 'x86_urgent_for_v6.17_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/cpuid: Remove transitional <asm/cpuid.h> header
  x86/sev: Ensure SVSM reserved fields in a page validation entry are initialized to zero
  virt: sev-guest: Satisfy linear mapping requirement in get_derived_key()
  x86/sev: Improve handling of writes to intercepted TSC MSRs
  x86/fpu: Fix NULL dereference in avx512_status()
  x86/bugs: Select best SRSO mitigation