This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
The ability to map PCI resources to user-space is controlled by global
defines. For vfio there is VFIO_PCI_MMAP which is only disabled on s390 and
controls mapping of PCI resources using vfio-pci with a fallback option via
the pread()/pwrite() interface.
For the PCI core there is ARCH_GENERIC_PCI_MMAP_RESOURCE which enables a
generic implementation for mapping PCI resources plus the newer sysfs
interface. Then there is HAVE_PCI_MMAP which can be used with custom
definitions of pci_mmap_resource_range() and the historical /proc/bus/pci
interface. Both mechanisms are all or nothing.
For s390 mapping PCI resources is possible and useful for testing and
certain applications such as QEMU's vfio-pci based user-space NVMe driver.
For certain devices, however access to PCI resources via mappings to
user-space is not possible and these must be excluded from the general PCI
resource mapping mechanisms.
Introduce pdev->non_mappable_bars to indicate that a PCI device's BARs can
not be accessed via mappings to user-space. In the future this enables
per-device restrictions of PCI resource mapping.
For now, set this flag for all PCI devices on s390 in line with the
existing, general disable of PCI resource mapping. As s390 is the only user
of the VFI_PCI_MMAP Kconfig options this can already be replaced with a
check of this new flag. Also add similar checks in the other code protected
by HAVE_PCI_MMAP respectively ARCH_GENERIC_PCI_MMAP in preparation for
enabling these for supported devices.
Link: https://lore.kernel.org/lkml/20250212132808.08dcf03c.alex.williamson@redhat.com/
Link: https://lore.kernel.org/r/20250226-vfio_pci_mmap-v7-2-c5c0f1d26efd@linux.ibm.com
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The ARCH_GENERIC_PCI_MMAP_RESOURCE symbol came up in a recent discussion,
and I noticed that this was left behind by an unfinished cleanup from 2017.
The only architecture that still relies on providing its own
pci_mmap_page_range() helper instead of using the generic
pci_mmap_resource_range() is sparc. Presumably the reasons for this have
not changed, but at least this can be simplified by converting sparc to use
the same interface as the others.
The only difference between the two is the device-specific offset that gets
added to or subtracted from vma->vm_pgoff.
Change the only caller of pci_mmap_page_range() in common code to subtract
this offset and call the modern interface, while adding it back in the
sparc implementation to preserve the existing behavior.
This removes the complexities of the dual interfaces from the common code,
and keeps it all specific to the sparc architecture code. According to
David Miller, the sparc code lets user space poke into the VGA I/O port
registers by mmapping the I/O space of the parent bridge device, which is
something that the generic pci_mmap_resource_range() code apparently does
not.
Link: https://lore.kernel.org/lkml/1519887203.622.3.camel@infradead.org/t/
Link: https://lore.kernel.org/lkml/20220714214657.2402250-3-shorne@gmail.com/
Link: https://lore.kernel.org/r/20220715153617.3393420-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Stafford Horne <shorne@gmail.com>
Remove variables and assignments that are never used.
Found by Krzysztof using cppcheck, e.g.,
$ cppcheck --enable=all --force
uselessAssignmentPtrArg drivers/pci/proc.c:102 Assignment of function parameter has no effect outside the function. Did you forget dereferencing it?
unreadVariable drivers/pci/setup-bus.c:1528 Variable 'old_flags' is assigned a value that is never used.
Reported-by: Krzysztof Wilczyński <kw@linux.com>
Link: https://lore.kernel.org/r/20220313192933.434746-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The struct pci_filp_private has no users outside drivers/pci/proc.c and is
only used when HAVE_PCI_MMAP is defined.
Wrap the struct pci_filp_private definition itself in #ifdef HAVE_PCI_MMAP.
Found by cppcheck:
$ cppcheck --enable=all --force drivers/pci/proc.c
drivers/pci/proc.c:192:6: style: struct member 'pci_filp_private::write_combine' is never used. [unusedStructMember]
Link: https://lore.kernel.org/r/20210706003145.3054881-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Since 3234ac664a ("/dev/mem: Revoke mappings when a driver claims
the region") /dev/kmem zaps PTEs when the kernel requests exclusive
acccess to an iomem region. And with CONFIG_IO_STRICT_DEVMEM, this is
the default for all driver uses.
Except there are two more ways to access PCI BARs: sysfs and proc mmap
support. Let's plug that hole.
For revoke_devmem() to work we need to link our vma into the same
address_space, with consistent vma->vm_pgoff. ->pgoff is already
adjusted, because that's how (io_)remap_pfn_range works, but for the
mapping we need to adjust vma->vm_file->f_mapping. The cleanest way is
to adjust this at at ->open time:
- for sysfs this is easy, now that binary attributes support this. We
just set bin_attr->mapping when mmap is supported
- for procfs it's a bit more tricky, since procfs PCI access has only
one file per device, and access to a specific resource first needs
to be set up with some ioctl calls. But mmap is only supported for
the same resources as sysfs exposes with mmap support, and otherwise
rejected, so we can set the mapping unconditionally at open time
without harm.
A special consideration is for arch_can_pci_mmap_io() - we need to
make sure that the ->f_mapping doesn't alias between ioport and iomem
space. There are only 2 ways in-tree to support mmap of ioports: generic
PCI mmap (ARCH_GENERIC_PCI_MMAP_RESOURCE), and sparc as the single
architecture hand-rolling. Both approaches support ioport mmap through a
special PFN range and not through magic PTE attributes. Aliasing is
therefore not a problem.
The only difference in access checks left is that sysfs PCI mmap does
not check for CAP_RAWIO. I'm not really sure whether that should be
added or not.
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Kees Cook <keescook@chromium.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-mm@kvack.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-media@vger.kernel.org
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20210204165831.2703772-3-daniel.vetter@ffwll.ch
Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.
From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.
The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.
There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/
- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.
The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.
The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:
lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.
This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.
New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.
The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.
Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"
* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
Any hardware that can potentially generate DMA has to be locked down in
order to avoid it being possible for an attacker to modify kernel code,
allowing them to circumvent disabled module loading or module signing.
Default to paranoid - in future we can potentially relax this for
sufficiently IOMMU-isolated devices.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: linux-pci@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warnings:
drivers/pci/proc.c: In function ‘proc_bus_pci_ioctl’:
drivers/pci/proc.c:216:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (arch_can_pci_mmap_wc()) {
^
drivers/pci/proc.c:225:2: note: here
default:
^~~~~~~
drivers/pci/xen-pcifront.c: In function ‘pcifront_backend_changed’:
drivers/pci/xen-pcifront.c:1105:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (xdev->state == XenbusStateClosed)
^
drivers/pci/xen-pcifront.c:1108:2: note: here
case XenbusStateClosing:
^~~~
Notice that, in this particular case, the /* fall through */
comment is placed at the very bottom of the case statement,
which is what GCC is expecting to find.
Warning level 3 was used: -Wimplicit-fallthrough=3
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Variants of proc_create{,_data} that directly take a struct seq_operations
argument and drastically reduces the boilerplate code in the callers.
All trivial callers converted over.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Remove pointless comments that tell us the file name, remove blank line
comments, follow multi-line comment conventions. No functional change
intended.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In all cases we know which BAR it is. Passing it in means that arch code
(or generic code; watch this space) won't have to go looking for it again.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This is relatively esoteric, and knowing that we don't have it makes life
easier in some cases rather than just an eventual -EINVAL from
pci_mmap_page_range().
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
