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2018-10-21page cache: Add and replace pages using the XArrayMatthew Wilcox
Use the XArray APIs to add and replace pages in the page cache. This removes two uses of the radix tree preload API and is significantly shorter code. It also removes the last user of __radix_tree_create() outside radix-tree.c itself, so make it static. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21ida: Convert to XArrayMatthew Wilcox
Use the XA_TRACK_FREE ability to track which entries have a free bit, similarly to how it uses the radix tree's IDR_FREE tag. This eliminates the per-cpu ida_bitmap preload, and fixes the memory consumption regression I introduced when making the IDR able to store any pointer. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Track free entries in an XArrayMatthew Wilcox
Add the optional ability to track which entries in an XArray are free and provide xa_alloc() to replace most of the functionality of the IDR. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add xa_reserve and xa_releaseMatthew Wilcox
This function reserves a slot in the XArray for users which need to acquire multiple locks before storing their entry in the tree and so cannot use a plain xa_store(). Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add xas_create_rangeMatthew Wilcox
This hopefully temporary function is useful for users who have not yet been converted to multi-index entries. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add xas_for_each_conflictMatthew Wilcox
This iterator iterates over each entry that is stored in the index or indices specified by the xa_state. This is intended for use for a conditional store of a multiindex entry, or to allow entries which are about to be removed from the xarray to be disposed of properly. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Step through an XArrayMatthew Wilcox
The xas_next and xas_prev functions move the xas index by one position, and adjust the rest of the iterator state to match it. This is more efficient than calling xas_set() as it keeps the iterator at the leaves of the tree instead of walking the iterator from the root each time. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Destroy an XArrayMatthew Wilcox
This function frees all the internal memory allocated to the xarray and reinitialises it to be empty. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Extract entries from an XArrayMatthew Wilcox
The xa_extract function combines the functionality of radix_tree_gang_lookup() and radix_tree_gang_lookup_tagged(). It extracts entries matching the specified filter into a normal array. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add XArray iteratorsMatthew Wilcox
The xa_for_each iterator allows the user to efficiently walk a range of the array, executing the loop body once for each entry in that range that matches the filter. This commit also includes xa_find() and xa_find_after() which are helper functions for xa_for_each() but may also be useful in their own right. In the xas family of functions, we have xas_for_each(), xas_find(), xas_next_entry(), xas_for_each_tagged(), xas_find_tagged(), xas_next_tagged() and xas_pause(). Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add XArray conditional store operationsMatthew Wilcox
Like cmpxchg(), xa_cmpxchg will only store to the index if the current entry matches the old entry. It returns the current entry, which is usually more useful than the errno returned by radix_tree_insert(). For the users who really only want the errno, the xa_insert() wrapper provides a more convenient calling convention. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add XArray unconditional store operationsMatthew Wilcox
xa_store() differs from radix_tree_insert() in that it will overwrite an existing element in the array rather than returning an error. This is the behaviour which most users want, and those that want more complex behaviour generally want to use the xas family of routines anyway. For memory allocation, xa_store() will first attempt to request memory from the slab allocator; if memory is not immediately available, it will drop the xa_lock and allocate memory, keeping a pointer in the xa_state. It does not use the per-CPU cache, although those will continue to exist until all radix tree users are converted to the xarray. This patch also includes xa_erase() and __xa_erase() for a streamlined way to store NULL. Since there is no need to allocate memory in order to store a NULL in the XArray, we do not need to trouble the user with deciding what memory allocation flags to use. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add XArray marksMatthew Wilcox
XArray marks are like the radix tree tags, only slightly more strongly typed. They are renamed in order to distinguish them from tagged pointers. This commit adds the basic get/set/clear operations. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Add XArray load operationMatthew Wilcox
The xa_load function brings with it a lot of infrastructure; xa_empty(), xa_is_err(), and large chunks of the XArray advanced API that are used to implement xa_load. As the test-suite demonstrates, it is possible to use the XArray functions on a radix tree. The radix tree functions depend on the GFP flags being stored in the root of the tree, so it's not possible to use the radix tree functions on an XArray. Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-21xarray: Define struct xa_nodeMatthew Wilcox
This is a direct replacement for struct radix_tree_node. A couple of struct members have changed name, so convert those. Use a #define so that radix tree users continue to work without change. Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Josef Bacik <jbacik@fb.com>
2018-10-21xarray: Add definition of struct xarrayMatthew Wilcox
This is a direct replacement for struct radix_tree_root. Some of the struct members have changed name; convert those, and use a #define so that radix_tree users continue to work without change. Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Josef Bacik <jbacik@fb.com>
2018-10-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
net/sched/cls_api.c has overlapping changes to a call to nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL to the 5th argument, and another (from 'net-next') added cb->extack instead of NULL to the 6th argument. net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to code which moved (to mr_table_dump)) in 'net-next'. Thanks to David Ahern for the heads up. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-19locking/lockdep: Make global debug_locks* variables read-mostlyWaiman Long
Make the frequently used lockdep global variable debug_locks read-mostly. As debug_locks_silent is sometime used together with debug_locks, it is also made read-mostly so that they can be close together. With false cacheline sharing, cacheline contention problem can happen depending on what get put into the same cacheline as debug_locks. Signed-off-by: Waiman Long <longman@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/1539913518-15598-2-git-send-email-longman@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-19locking/lockdep: Fix debug_locks off performance problemWaiman Long
It was found that when debug_locks was turned off because of a problem found by the lockdep code, the system performance could drop quite significantly when the lock_stat code was also configured into the kernel. For instance, parallel kernel build time on a 4-socket x86-64 server nearly doubled. Further analysis into the cause of the slowdown traced back to the frequent call to debug_locks_off() from the __lock_acquired() function probably due to some inconsistent lockdep states with debug_locks off. The debug_locks_off() function did an unconditional atomic xchg to write a 0 value into debug_locks which had already been set to 0. This led to severe cacheline contention in the cacheline that held debug_locks. As debug_locks is being referenced in quite a few different places in the kernel, this greatly slow down the system performance. To prevent that trashing of debug_locks cacheline, lock_acquired() and lock_contended() now checks the state of debug_locks before proceeding. The debug_locks_off() function is also modified to check debug_locks before calling __debug_locks_off(). Signed-off-by: Waiman Long <longman@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Link: http://lkml.kernel.org/r/1539913518-15598-1-git-send-email-longman@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-10-16lib: Fix ia64 bootloader linkageAlexander Shishkin
kbuild robot reports that since commit ce76d938dd98 ("lib: Add memcat_p(): paste 2 pointer arrays together") the ia64/hp/sim/boot fails to link: > LD arch/ia64/hp/sim/boot/bootloader > lib/string.o: In function `__memcat_p': > string.c:(.text+0x1f22): undefined reference to `__kmalloc' > string.c:(.text+0x1ff2): undefined reference to `__kmalloc' > make[1]: *** [arch/ia64/hp/sim/boot/Makefile:37: arch/ia64/hp/sim/boot/bootloader] Error 1 The reason is, the above commit, via __memcat_p(), adds a call to __kmalloc to string.o, which happens to be used in the bootloader, but there's no kmalloc or slab or anything. Since the linker would only pull in objects that contain referenced symbols, moving __memcat_p() to a different compilation unit solves the problem. Fixes: ce76d938dd98 ("lib: Add memcat_p(): paste 2 pointer arrays together") Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reported-by: kbuild test robot <lkp@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-15test_ida: Fix lockdep warningMatthew Wilcox
The IDA was declared on the stack instead of statically, so lockdep triggered a warning that it was improperly initialised. Reported-by: 0day bot Tested-by: Rong Chen <rong.a.chen@intel.com> Signed-off-by: Matthew Wilcox <willy@infradead.org>
2018-10-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts were easy to resolve using immediate context mostly, except the cls_u32.c one where I simply too the entire HEAD chunk. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12doc: printk-formats: Remove bogus kobject references for device nodesGeert Uytterhoeven
When converting from text to rst, the kobjects section and its sole subsection about device tree nodes were coalesced into a single section, yielding an inconsistent result. Remove all references to kobjects, as 1. Device tree object pointers are not compatible to kobject pointers (the former may embed the latter, though), and 2. there are no printk formats defined for kobject types. Update the vsprintf() source code comments to match the above. Fixes: b3ed23213eab1e08 ("doc: convert printk-formats.txt to rst") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-10-12Merge tag 'mtd/fixes-for-4.19-rc8' of git://git.infradead.org/linux-mtdGreg Kroah-Hartman
Boris writes: "mdt: fix for 4.19-rc8 * Fix a stack overflow in lib/bch.c" * tag 'mtd/fixes-for-4.19-rc8' of git://git.infradead.org/linux-mtd: lib/bch: fix possible stack overrun
2018-10-12lib/vsprintf: Hash printed address for netdev bits fallbackGeert Uytterhoeven
The handler for "%pN" falls back to printing the raw pointer value when using a different format than the (sole supported) special format "%pNF", potentially leaking sensitive information regarding the kernel layout in memory. Avoid this leak by printing the hashed address instead. Note that there are no in-tree users of the fallback. Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p") Link: http://lkml.kernel.org/r/20181011084249.4520-4-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12lib/vsprintf: Hash legacy clock addressesGeert Uytterhoeven
On platforms using the Common Clock Framework, "%pC" prints the clock's name. On legacy platforms, it prints the unhashed clock's address, potentially leaking sensitive information regarding the kernel layout in memory. Avoid this leak by printing the hashed address instead. To distinguish between clocks, a 32-bit unique identifier is as good as an actual pointer value. Fixes: ad67b74d2469d9b8 ("printk: hash addresses printed with %p") Link: http://lkml.kernel.org/r/20181011084249.4520-3-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12lib/vsprintf: Prepare for more general use of ptr_to_id()Geert Uytterhoeven
Move the function and its dependencies up so it can be called from special pointer type formatting routines. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: Split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12lib/vsprintf: Make ptr argument conts in ptr_to_id()Geert Uytterhoeven
Make the ptr argument const to avoid adding casts in future callers. Link: http://lkml.kernel.org/r/20181011084249.4520-2-geert+renesas@glider.be To: "Tobin C . Harding" <me@tobin.cc> To: Andrew Morton <akpm@linux-foundation.org> To: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [pmladek@suse.com: split into separate patch] Signed-off-by: Petr Mladek <pmladek@suse.com>
2018-10-12lib/bch: fix possible stack overrunArnd Bergmann
The previous patch introduced very large kernel stack usage and a Makefile change to hide the warning about it. From what I can tell, a number of things went wrong here: - The BCH_MAX_T constant was set to the maximum value for 'n', not the maximum for 't', which is much smaller. - The stack usage is actually larger than the entire kernel stack on some architectures that can use 4KB stacks (m68k, sh, c6x), which leads to an immediate overrun. - The justification in the patch description claimed that nothing changed, however that is not the case even without the two points above: the configuration is machine specific, and most boards never use the maximum BCH_ECC_WORDS() length but instead have something much smaller. That maximum would only apply to machines that use both the maximum block size and the maximum ECC strength. The largest value for 't' that I could find is '32', which in turn leads to a 60 byte array instead of 2048 bytes. Making it '64' for future extension seems also worthwhile, with 120 bytes for the array. Anything larger won't fit into the OOB area on NAND flash. With that changed, the warning can be enabled again. Only linux-4.19+ contains the breakage, so this is only needed as a stable backport if it does not make it into the release. Fixes: 02361bc77888 ("lib/bch: Remove VLA usage") Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: stable@vger.kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-10-11Makefile: Globally enable VLA warningKees Cook
Now that Variable Length Arrays (VLAs) have been entirely removed[1] from the kernel, enable the VLA warning globally. The only exceptions to this are the KASan an UBSan tests which are explicitly checking that VLAs trigger their respective tests. [1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Airlie <airlied@linux.ie> Cc: linux-kbuild@vger.kernel.org Cc: intel-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Signed-off-by: Kees Cook <keescook@chromium.org>
2018-10-11lib: Add memcat_p(): paste 2 pointer arrays togetherAlexander Shishkin
This adds a helper to paste 2 pointer arrays together, useful for merging various types of attribute arrays. There are a few places in the kernel tree where this is open coded, and I just added one more in the STM class. The naming is inspired by memset_p() and memcat(), and partial credit for it goes to Andy Shevchenko. This patch adds the function wrapped in a type-enforcing macro and a test module. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-10Merge tag 'trace-v4.19-rc5' of ↵Greg Kroah-Hartman
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Steven writes: "vsprint fix: It was reported that trace_printk() was not reporting properly values that came after a dereference pointer. trace_printk() utilizes vbin_printf() and bstr_printf() to keep the overhead of tracing down. vbin_printf() does not do any conversions and just stors the string format and the raw arguments into the buffer. bstr_printf() is used to read the buffer and does the conversions to complete the printf() output. This can be troublesome with dereferenced pointers because the reference may be different from the time vbin_printf() is called to the time bstr_printf() is called. To fix this, a prior commit changed vbin_printf() to convert dereferenced pointers into strings and load the converted string into the buffer. But the change to bstr_printf() had an off-by-one error and didn't account for the nul character at the end of the string and this corrupted the rest of the values in the format that came after a dereferenced pointer." * tag 'trace-v4.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: vsprintf: Fix off-by-one bug in bstr_printf() processing dereferenced pointers
2018-10-09s390/kasan: add option for 4-level paging supportVasily Gorbik
By default 3-level paging is used when the kernel is compiled with kasan support. Add 4-level paging option to support systems with more then 3TB of physical memory and to cover 4-level paging specific code with kasan as well. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2018-10-08Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2018-10-08 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) sk_lookup_[tcp|udp] and sk_release helpers from Joe Stringer which allow BPF programs to perform lookups for sockets in a network namespace. This would allow programs to determine early on in processing whether the stack is expecting to receive the packet, and perform some action (eg drop, forward somewhere) based on this information. 2) per-cpu cgroup local storage from Roman Gushchin. Per-cpu cgroup local storage is very similar to simple cgroup storage except all the data is per-cpu. The main goal of per-cpu variant is to implement super fast counters (e.g. packet counters), which don't require neither lookups, neither atomic operations in a fast path. The example of these hybrid counters is in selftests/bpf/netcnt_prog.c 3) allow HW offload of programs with BPF-to-BPF function calls from Quentin Monnet 4) support more than 64-byte key/value in HW offloaded BPF maps from Jakub Kicinski 5) rename of libbpf interfaces from Andrey Ignatov. libbpf is maturing as a library and should follow good practices in library design and implementation to play well with other libraries. This patch set brings consistent naming convention to global symbols. 6) relicense libbpf as LGPL-2.1 OR BSD-2-Clause from Alexei Starovoitov to let Apache2 projects use libbpf 7) various AF_XDP fixes from Björn and Magnus ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08netlink: Add strict version of nlmsg_parse and nla_parseDavid Ahern
nla_parse is currently lenient on message parsing, allowing type to be 0 or greater than max expected and only logging a message "netlink: %d bytes leftover after parsing attributes in process `%s'." if the netlink message has unknown data at the end after parsing. What this could mean is that the header at the front of the attributes is actually wrong and the parsing is shifted from what is expected. Add a new strict version that actually fails with EINVAL if there are any bytes remaining after the parsing loop completes, if the atttrbitue type is 0 or greater than max expected. Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Christian Brauner <christian@brauner.io> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-05vsprintf: Fix off-by-one bug in bstr_printf() processing dereferenced pointersSteven Rostedt (VMware)
The functions vbin_printf() and bstr_printf() are used by trace_printk() to try to keep the overhead down during printing. trace_printk() uses vbin_printf() at the time of execution, as it only scans the fmt string to record the printf values into the buffer, and then uses vbin_printf() to do the conversions to print the string based on the format and the saved values in the buffer. This is an issue for dereferenced pointers, as before commit 841a915d20c7b, the processing of the pointer could happen some time after the pointer value was recorded (reading the trace buffer). This means the processing of the value at a later time could show different results, or even crash the system, if the pointer no longer existed. Commit 841a915d20c7b addressed this by processing dereferenced pointers at the time of execution and save the result in the ring buffer as a string. The bstr_printf() would then treat these pointers as normal strings, and print the value. But there was an off-by-one bug here, where after processing the argument, it move the pointer only "strlen(arg)" which made the arg pointer not point to the next argument in the ring buffer, but instead point to the nul character of the last argument. This causes any values after a dereferenced pointer to be corrupted. Cc: stable@vger.kernel.org Fixes: 841a915d20c7b ("vsprintf: Do not have bprintf dereference pointers") Reported-by: Nikolay Borisov <nborisov@suse.com> Tested-by: Nikolay Borisov <nborisov@suse.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-10-04ARM: 8800/1: use choice for kernel unwindersStefan Agner
While in theory multiple unwinders could be compiled in, it does not make sense in practise. Use a choice to make the unwinder selection mutually exclusive and mandatory. Already before this commit it has not been possible to deselect FRAME_POINTER. Remove the obsolete comment. Furthermore, to produce a meaningful backtrace with FRAME_POINTER enabled the kernel needs a specific function prologue: mov ip, sp stmfd sp!, {fp, ip, lr, pc} sub fp, ip, #4 To get to the required prologue gcc uses apcs and no-sched-prolog. This compiler options are not available on clang, and clang is not able to generate the required prologue. Make the FRAME_POINTER config symbol depending on !clang. Suggested-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Stefan Agner <stefan@agner.ch> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2018-10-01netlink: add validation function to policyJohannes Berg
Add the ability to have an arbitrary validation function attached to a netlink policy that doesn't already use the validation_data pointer in another way. This can be useful to validate for example the content of a binary attribute, like in nl80211 the "(information) elements", which must be valid streams of "u8 type, u8 length, u8 value[length]". Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-01netlink: add attribute range validation to policyJohannes Berg
Without further bloating the policy structs, we can overload the `validation_data' pointer with a struct of s16 min, max and use those to validate ranges in NLA_{U,S}{8,16,32,64} attributes. It may sound strange to validate NLA_U32 with a s16 max, but in many cases NLA_U32 is used for enums etc. since there's no size benefit in using a smaller attribute width anyway, due to netlink attribute alignment; in cases like that it's still useful, particularly when the attribute really transports an enum value. Doing so lets us remove quite a bit of validation code, if we can be sure that these attributes aren't used by userspace in places where they're ignored today. To achieve all this, split the 'type' field and introduce a new 'validation_type' field which indicates what further validation (beyond the validation prescribed by the type of the attribute) is done. This currently allows for no further validation (the default), as well as min, max and range checks. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02lib/xz: Put CRC32_POLY_LE in xz_private.hJoel Stanley
This fixes a regression introduced by faa16bc404d72a5 ("lib: Use existing define with polynomial"). The cleanup added a dependency on include/linux, which broke the PowerPC boot wrapper/decompresser when KERNEL_XZ is enabled: BOOTCC arch/powerpc/boot/decompress.o In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:233, from arch/powerpc/boot/decompress.c:42: arch/powerpc/boot/../../../lib/xz/xz_crc32.c:18:10: fatal error: linux/crc32poly.h: No such file or directory #include <linux/crc32poly.h> ^~~~~~~~~~~~~~~~~~~ The powerpc decompresser is a hairy corner of the kernel. Even while building a 64-bit kernel it needs to build a 32-bit binary and therefore avoid including files from include/linux. This allows users of the xz library to avoid including headers from 'include/linux/' while still achieving the cleanup of the magic number. Fixes: faa16bc404d72a5 ("lib: Use existing define with polynomial") Reported-by: Meelis Roos <mroos@linux.ee> Reported-by: kbuild test robot <lkp@intel.com> Suggested-by: Christophe LEROY <christophe.leroy@c-s.fr> Signed-off-by: Joel Stanley <joel@jms.id.au> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-29xarray: Change definition of sibling entriesMatthew Wilcox
Instead of storing a pointer to the slot containing the canonical entry, store the offset of the slot. Produces slightly more efficient code (~300 bytes) and simplifies the implementation. Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Josef Bacik <jbacik@fb.com>
2018-09-29xarray: Replace exceptional entriesMatthew Wilcox
Introduce xarray value entries and tagged pointers to replace radix tree exceptional entries. This is a slight change in encoding to allow the use of an extra bit (we can now store BITS_PER_LONG - 1 bits in a value entry). It is also a change in emphasis; exceptional entries are intimidating and different. As the comment explains, you can choose to store values or pointers in the xarray and they are both first-class citizens. Signed-off-by: Matthew Wilcox <willy@infradead.org> Reviewed-by: Josef Bacik <jbacik@fb.com>
2018-09-29idr: Permit any valid kernel pointer to be storedMatthew Wilcox
An upcoming change to the encoding of internal entries will set the bottom two bits to 0b10. Unfortunately, m68k only aligns some data structures to 2 bytes, so the IDR will interpret them as internal entries and things will go badly wrong. Change the radix tree so that it stops either when the node indicates that it's the bottom of the tree (shift == 0) or when the entry is not an internal entry. This means we cannot insert an arbitrary kernel pointer as a multiorder entry, but the IDR does not permit multiorder entries. Annoyingly, this means the IDR can no longer take advantage of the radix tree's ability to store a single entry at offset 0 without allocating memory. A pointer which is 2-byte aligned cannot be stored directly in the root as it would be indistinguishable from a node, so we must allocate a node in order to store a 2-byte pointer at index 0. The idr_replace() function does not take a GFP flags argument, so cannot allocate memory. If a user inserts a 4-byte aligned pointer at index 0 and then replaces it with a 2-byte aligned pointer, we must be able to store it. Arbitrary pointer values are still not permitted; pointers of the form 2 + (i * 4) for values of i between 0 and 1023 are reserved for the implementation. These are not valid kernel pointers as they would point into the zero page. This change does cause a runtime memory consumption regression for the IDA. I will recover that later. Signed-off-by: Matthew Wilcox <willy@infradead.org> Tested-by: Guenter Roeck <linux@roeck-us.net>
2018-09-28netlink: add nested array policy validationJohannes Berg
Sometimes nested netlink attributes are just used as arrays, with the nla_type() of each not being used; we have this in nl80211 and e.g. NFTA_SET_ELEM_LIST_ELEMENTS. Add the ability to validate this type of message directly in the policy, by adding the type NLA_NESTED_ARRAY which does exactly this: require a first level of nesting but ignore the attribute type, and then inside each require a second level of nested and validate those attributes against a given policy (if present). Note that some nested array types actually require that all of the entries have the same index, this is possible to express in a nested policy already, apart from the validation that only the one allowed type is used. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-28netlink: allow NLA_NESTED to specify nested policy to validateJohannes Berg
Now that we have a validation_data pointer, and the len field in the policy is unused for NLA_NESTED, we can allow using them both to have nested validation. This can be nice in code, although we still have to use nla_parse_nested() or similar which would also take a policy; however, it also serves as documentation in the policy without requiring a look at the code. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-28netlink: move extack setting into validate_nla()Johannes Berg
This unifies the code between nla_parse() which sets the bad attribute pointer and an error message, and nla_validate() which only sets the bad attribute pointer. It also cleans up the code for NLA_REJECT and paves the way for nested policy validation, as it will allow us to easily skip setting the "generic" message without any extra args like the **error_msg now, just passing the extack through is now enough. While at it, remove the unnecessary label in nla_parse(). Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-28netlink: make validation_data constJohannes Berg
The validation data is only used within the policy that should usually already be const, and isn't changed in any code that uses it. Therefore, make the validation_data pointer const. While at it, remove the duplicate variable in the bitfield validation that I'd otherwise have to change to const. Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-28netlink: remove NLA_NESTED_COMPATJohannes Berg
This isn't used anywhere, so we might as well get rid of it. Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-27bpf: test_bpf: add init_net to dev for flow_dissectorSong Liu
Latest changes in __skb_flow_dissect() assume skb->dev has valid nd_net. However, this is not true for test_bpf. As a result, test_bpf.ko crashes the system with the following stack trace: [ 1133.716622] BUG: unable to handle kernel paging request at 0000000000001030 [ 1133.716623] PGD 8000001fbf7ee067 [ 1133.716624] P4D 8000001fbf7ee067 [ 1133.716624] PUD 1f6c1cf067 [ 1133.716625] PMD 0 [ 1133.716628] Oops: 0000 [#1] SMP PTI [ 1133.716630] CPU: 7 PID: 40473 Comm: modprobe Kdump: loaded Not tainted 4.19.0-rc5-00805-gca11cc92ccd2 #1167 [ 1133.716631] Hardware name: Wiwynn Leopard-Orv2/Leopard-DDR BW, BIOS LBM12.5 12/06/2017 [ 1133.716638] RIP: 0010:__skb_flow_dissect+0x83/0x1680 [ 1133.716639] Code: 04 00 00 41 0f b7 44 24 04 48 85 db 4d 8d 14 07 0f 84 01 02 00 00 48 8b 43 10 48 85 c0 0f 84 e5 01 00 00 48 8b 80 a8 04 00 00 <48> 8b 90 30 10 00 00 48 85 d2 0f 84 dd 01 00 00 31 c0 b9 05 00 00 [ 1133.716640] RSP: 0018:ffffc900303c7a80 EFLAGS: 00010282 [ 1133.716642] RAX: 0000000000000000 RBX: ffff881fea0b7400 RCX: 0000000000000000 [ 1133.716643] RDX: ffffc900303c7bb4 RSI: ffffffff8235c3e0 RDI: ffff881fea0b7400 [ 1133.716643] RBP: ffffc900303c7b80 R08: 0000000000000000 R09: 000000000000000e [ 1133.716644] R10: ffffc900303c7bb4 R11: ffff881fb6840400 R12: ffffffff8235c3e0 [ 1133.716645] R13: 0000000000000008 R14: 000000000000001e R15: ffffc900303c7bb4 [ 1133.716646] FS: 00007f54e75d3740(0000) GS:ffff881fff5c0000(0000) knlGS:0000000000000000 [ 1133.716648] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1133.716649] CR2: 0000000000001030 CR3: 0000001f6c226005 CR4: 00000000003606e0 [ 1133.716649] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 1133.716650] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 1133.716651] Call Trace: [ 1133.716660] ? sched_clock_cpu+0xc/0xa0 [ 1133.716662] ? sched_clock_cpu+0xc/0xa0 [ 1133.716665] ? log_store+0x1b5/0x260 [ 1133.716667] ? up+0x12/0x60 [ 1133.716669] ? skb_get_poff+0x4b/0xa0 [ 1133.716674] ? __kmalloc_reserve.isra.47+0x2e/0x80 [ 1133.716675] skb_get_poff+0x4b/0xa0 [ 1133.716680] bpf_skb_get_pay_offset+0xa/0x10 [ 1133.716686] ? test_bpf_init+0x578/0x1000 [test_bpf] [ 1133.716690] ? netlink_broadcast_filtered+0x153/0x3d0 [ 1133.716695] ? free_pcppages_bulk+0x324/0x600 [ 1133.716696] ? 0xffffffffa0279000 [ 1133.716699] ? do_one_initcall+0x46/0x1bd [ 1133.716704] ? kmem_cache_alloc_trace+0x144/0x1a0 [ 1133.716709] ? do_init_module+0x5b/0x209 [ 1133.716712] ? load_module+0x2136/0x25d0 [ 1133.716715] ? __do_sys_finit_module+0xba/0xe0 [ 1133.716717] ? __do_sys_finit_module+0xba/0xe0 [ 1133.716719] ? do_syscall_64+0x48/0x100 [ 1133.716724] ? entry_SYSCALL_64_after_hwframe+0x44/0xa9 This patch fixes tes_bpf by using init_net in the dummy dev. Fixes: d58e468b1112 ("flow_dissector: implements flow dissector BPF hook") Reported-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Petar Penkov <ppenkov@google.com> Signed-off-by: Song Liu <songliubraving@fb.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-09-26percpu-refcount: Introduce percpu_ref_resurrect()Bart Van Assche
This function will be used in a later patch to switch the struct request_queue q_usage_counter from killed back to live. In contrast to percpu_ref_reinit(), this new function does not require that the refcount is zero. Signed-off-by: Bart Van Assche <bvanassche@acm.org> Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Ming Lei <ming.lei@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jianchao Wang <jianchao.w.wang@oracle.com> Cc: Hannes Reinecke <hare@suse.com> Cc: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Jens Axboe <axboe@kernel.dk>