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2018-02-22metag: Remove arch/metag/James Hogan1-213/+0
The earliest Meta architecture port of Linux I have a record of was an import of a Meta port of Linux v2.4.1 in February 2004, which was worked on significantly over the next few years by Graham Whaley, Will Newton, Matt Fleming, myself and others. Eventually the port was merged into mainline in v3.9 in March 2013, not long after Imagination Technologies bought MIPS Technologies and shifted its CPU focus over to the MIPS architecture. As a result, though the port was maintained for a while, kept on life support for a while longer, and useful for testing a few specific drivers for which I don't have ready access to the equivalent MIPS hardware, it is now essentially dead with no users. It is also stuck using an out-of-tree toolchain based on GCC 4.2.4 which is no longer maintained, now struggles to build modern kernels due to toolchain bugs, and doesn't itself build with a modern GCC. The latest buildroot port is still using an old uClibc snapshot which is no longer served, and the latest uClibc doesn't build with GCC 4.2.4. So lets call it a day and drop the Meta architecture port from the kernel. RIP Meta. Signed-off-by: James Hogan <jhogan@kernel.org> Link: https://lkml.kernel.org/r/95906b76-6ce1-3f84-eaba-c29b4ae952eb@roeck-us.net Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Graham Whaley <graham.whaley@gmail.com> Cc: linux-metag@vger.kernel.org
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
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>
2017-05-15kill strlen_user()Al Viro1-2/+0
no callers, no consistent semantics, no sane way to use it... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-05-10Merge tag 'metag-for-v4.12' of ↵Linus Torvalds1-20/+38
git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag Pull metag updates from James Hogan: "These patches primarily make some usercopy improvements (following on from the recent usercopy fixes): - reformat and simplify rapf copy loops - add 64-bit get_user support And fix a couple more uaccess issues, partily pointed out by Al: - fix access_ok() serious shortcomings - fix strncpy_from_user() address validation Also included is a trivial removal of a redundant increment" * tag 'metag-for-v4.12' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag: metag/mm: Drop pointless increment metag/uaccess: Check access_ok in strncpy_from_user metag/uaccess: Fix access_ok() metag/usercopy: Add 64-bit get_user support metag/usercopy: Simplify rapf loop fixup corner case metag/usercopy: Reformat rapf loop inline asm
2017-05-02metag/uaccess: Check access_ok in strncpy_from_userJames Hogan1-2/+7
The metag implementation of strncpy_from_user() doesn't validate the src pointer, which could allow reading of arbitrary kernel memory. Add a short access_ok() check to prevent that. Its still possible for it to read across the user/kernel boundary, but it will invariably reach a NUL character after only 9 bytes, leaking only a static kernel address being loaded into D0Re0 at the beginning of __start, which is acceptable for the immediate fix. Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org Cc: stable@vger.kernel.org
2017-05-02metag/uaccess: Fix access_ok()James Hogan1-16/+24
The __user_bad() macro used by access_ok() has a few corner cases noticed by Al Viro where it doesn't behave correctly: - The kernel range check has off by 1 errors which permit access to the first and last byte of the kernel mapped range. - The kernel range check ends at LINCORE_BASE rather than META_MEMORY_LIMIT, which is ineffective when the kernel is in global space (an extremely uncommon configuration). There are a couple of other shortcomings here too: - Access to the whole of the other address space is permitted (i.e. the global half of the address space when the kernel is in local space). This isn't ideal as it could theoretically still contain privileged mappings set up by the bootloader. - The size argument is unused, permitting user copies which start on valid pages at the end of the user address range and cross the boundary into the kernel address space (e.g. addr = 0x3ffffff0, size > 0x10). It isn't very convenient to add size checks when disallowing certain regions, and it seems far safer to be sure and explicit about what userland is able to access, so invert the logic to allow certain regions instead, and fix the off by 1 errors and missing size checks. This also allows the get_fs() == KERNEL_DS check to be more easily optimised into the user address range case. We now have 3 such allowed regions: - The user address range (incorporating the get_fs() == KERNEL_DS check). - NULL (some kernel code expects this to work, and we'll always catch the fault anyway). - The core code memory region. Fixes: 373cd784d0fc ("metag: Memory handling") Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org Cc: stable@vger.kernel.org
2017-04-05metag/usercopy: Switch to RAW_COPY_USERJames Hogan1-29/+2
Switch to using raw user copy instead of providing metag specific [__]copy_{to,from}_user[_inatomic](). This simplifies the metag uaccess.h and allows us to take advantage of extra checking in the generic versions. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-metag@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-04-05Merge branch 'fixes' of ↵Al Viro1-7/+8
git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag into uaccess.metag
2017-04-05metag/usercopy: Add 64-bit get_user supportJames Hogan1-2/+7
Metag already supports 64-bit put_user, so add support for 64-bit get_user too so that the test_user_copy module can test both. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org
2017-04-05metag/usercopy: Zero rest of buffer from copy_from_userJames Hogan1-7/+8
Currently we try to zero the destination for a failed read from userland in fixup code in the usercopy.c macros. The rest of the destination buffer is then zeroed from __copy_user_zeroing(), which is used for both copy_from_user() and __copy_from_user(). Unfortunately we fail to zero in the fixup code as D1Ar1 is set to 0 before the fixup code entry labels, and __copy_from_user() shouldn't even be zeroing the rest of the buffer. Move the zeroing out into copy_from_user() and rename __copy_user_zeroing() to raw_copy_from_user() since it no longer does any zeroing. This also conveniently matches the name needed for RAW_COPY_USER support in a later patch. Fixes: 373cd784d0fc ("metag: Memory handling") Reported-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org Cc: stable@vger.kernel.org
2017-03-28metag: kill verify_area()Al Viro1-5/+0
Deprecated in 2.6.12, killed in 2.6.13. Time to end that depravity, let's bury the body... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-28metag: switch to generic extable.hAl Viro1-17/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-28new helper: uaccess_kernel()Al Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-05uaccess: drop duplicate includes from asm/uaccess.hAl Viro1-1/+0
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-03-05uaccess: move VERIFY_{READ,WRITE} definitions to linux/uaccess.hAl Viro1-3/+0
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-13metag: copy_from_user() should zero the destination on access_ok() failureAl Viro1-1/+2
Cc: stable@vger.kernel.org Acked-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-01-13metag: fix put_user sparse errorsMichael S. Tsirkin1-8/+13
virtio wants to write bitwise types to userspace using put_user. At the moment this triggers sparse errors, since the value is passed through an integer. For example: __le32 __user *p; __le32 x; put_user(x, p); is safe, but currently triggers a sparse warning. Fix that up using __force. This also fixes warnings due to writing a pointer out to userland. Note: this does not suppress any useful sparse checks since callers do a cast (__typeof__(*(ptr))) (x) which in turn forces all the necessary type checks. Suggested-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: James Hogan <james.hogan@imgtec.com>
2015-01-13metag/uaccess: fix sparse errorsMichael S. Tsirkin1-2/+2
virtio wants to read bitwise types from userspace using get_user. At the moment this triggers sparse errors, since the value is passed through an integer. Fix that up using __force. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: James Hogan <james.hogan@imgtec.com>
2013-03-02metag: Memory handlingJames Hogan1-0/+241
Meta has instructions for accessing: - bytes - GETB (1 byte) - words - GETW (2 bytes) - doublewords - GETD (4 bytes) - longwords - GETL (8 bytes) All accesses must be aligned. Unaligned accesses can be detected and made to fault on Meta2, however it isn't possible to fix up unaligned writes so we don't bother fixing up reads either. This patch adds metag memory handling code including: - I/O memory (io.h, ioremap.c): Actually any virtual memory can be accessed with these helpers. A part of the non-MMUable address space is used for memory mapped I/O. The ioremap() function is implemented one to one for non-MMUable addresses. - User memory (uaccess.h, usercopy.c): User memory is directly accessible from privileged code. - Kernel memory (maccess.c): probe_kernel_write() needs to be overwridden to use the I/O functions when doing a simple aligned write to non-writecombined memory, otherwise the write may be split by the generic version. Note that due to the fact that a portion of the virtual address space is non-MMUable, and therefore always maps directly to the physical address space, metag specific I/O functions are made available (metag_in32, metag_out32 etc). These cast the address argument to a pointer so that they can be used with raw physical addresses. These accessors are only to be used for accessing fixed core Meta architecture registers in the non-MMU region, and not for any SoC/peripheral registers. Signed-off-by: James Hogan <james.hogan@imgtec.com>