user/sven/linux.git/include, branch v4.14.124

include/linux/module.h: copy init/exit attrs to init/cleanup_module

2019-06-09T07:18:19Z

commit a6e60d84989fa0e91db7f236eda40453b0e44afa upstream. The upcoming GCC 9 release extends the -Wmissing-attributes warnings (enabled by -Wall) to C and aliases: it warns when particular function attributes are missing in the aliases but not in their target. In particular, it triggers for all the init/cleanup_module aliases in the kernel (defined by the module_init/exit macros), ending up being very noisy. These aliases point to the __init/__exit functions of a module, which are defined as __cold (among other attributes). However, the aliases themselves do not have the __cold attribute. Since the compiler behaves differently when compiling a __cold function as well as when compiling paths leading to calls to __cold functions, the warning is trying to point out the possibly-forgotten attribute in the alias. In order to keep the warning enabled, we decided to silence this case. Ideally, we would mark the aliases directly as __init/__exit. However, there are currently around 132 modules in the kernel which are missing __init/__exit in their init/cleanup functions (either because they are missing, or for other reasons, e.g. the functions being called from somewhere else); and a section mismatch is a hard error. A conservative alternative was to mark the aliases as __cold only. However, since we would like to eventually enforce __init/__exit to be always marked, we chose to use the new __copy function attribute (introduced by GCC 9 as well to deal with this). With it, we copy the attributes used by the target functions into the aliases. This way, functions that were not marked as __init/__exit won't have their aliases marked either, and therefore there won't be a section mismatch. Note that the warning would go away marking either the extern declaration, the definition, or both. However, we only mark the definition of the alias, since we do not want callers (which only see the declaration) to be compiled as if the function was __cold (and therefore the paths leading to those calls would be assumed to be unlikely). Link: https://lore.kernel.org/lkml/20190123173707.GA16603@gmail.com/ Link: https://lore.kernel.org/lkml/20190206175627.GA20399@gmail.com/ Suggested-by: Martin Sebor Acked-by: Jessica Yu Signed-off-by: Miguel Ojeda Signed-off-by: Stefan Agner Signed-off-by: Greg Kroah-Hartman

Compiler Attributes: add support for __copy (gcc >= 9)

2019-06-09T07:18:19Z

commit c0d9782f5b6d7157635ae2fd782a4b27d55a6013 upstream. From the GCC manual: copy copy(function) The copy attribute applies the set of attributes with which function has been declared to the declaration of the function to which the attribute is applied. The attribute is designed for libraries that define aliases or function resolvers that are expected to specify the same set of attributes as their targets. The copy attribute can be used with functions, variables, or types. However, the kind of symbol to which the attribute is applied (either function or variable) must match the kind of symbol to which the argument refers. The copy attribute copies only syntactic and semantic attributes but not attributes that affect a symbol’s linkage or visibility such as alias, visibility, or weak. The deprecated attribute is also not copied. https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html The upcoming GCC 9 release extends the -Wmissing-attributes warnings (enabled by -Wall) to C and aliases: it warns when particular function attributes are missing in the aliases but not in their target, e.g.: void __cold f(void) {} void __alias("f") g(void); diagnoses: warning: 'g' specifies less restrictive attribute than its target 'f': 'cold' [-Wmissing-attributes] Using __copy(f) we can copy the __cold attribute from f to g: void __cold f(void) {} void __copy(f) __alias("f") g(void); This attribute is most useful to deal with situations where an alias is declared but we don't know the exact attributes the target has. For instance, in the kernel, the widely used module_init/exit macros define the init/cleanup_module aliases, but those cannot be marked always as __init/__exit since some modules do not have their functions marked as such. Suggested-by: Martin Sebor Reviewed-by: Nick Desaulniers Signed-off-by: Miguel Ojeda Signed-off-by: Stefan Agner Signed-off-by: Greg Kroah-Hartman

memcg: make it work on sparse non-0-node systems

2019-06-09T07:18:17Z

commit 3e8589963773a5c23e2f1fe4bcad0e9a90b7f471 upstream. We have a single node system with node 0 disabled: Scanning NUMA topology in Northbridge 24 Number of physical nodes 2 Skipping disabled node 0 Node 1 MemBase 0000000000000000 Limit 00000000fbff0000 NODE_DATA(1) allocated [mem 0xfbfda000-0xfbfeffff] This causes crashes in memcg when system boots: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 #PF error: [normal kernel read fault] ... RIP: 0010:list_lru_add+0x94/0x170 ... Call Trace: d_lru_add+0x44/0x50 dput.part.34+0xfc/0x110 __fput+0x108/0x230 task_work_run+0x9f/0xc0 exit_to_usermode_loop+0xf5/0x100 It is reproducible as far as 4.12. I did not try older kernels. You have to have a new enough systemd, e.g. 241 (the reason is unknown -- was not investigated). Cannot be reproduced with systemd 234. The system crashes because the size of lru array is never updated in memcg_update_all_list_lrus and the reads are past the zero-sized array, causing dereferences of random memory. The root cause are list_lru_memcg_aware checks in the list_lru code. The test in list_lru_memcg_aware is broken: it assumes node 0 is always present, but it is not true on some systems as can be seen above. So fix this by avoiding checks on node 0. Remember the memcg-awareness by a bool flag in struct list_lru. Link: http://lkml.kernel.org/r/20190522091940.3615-1-jslaby@suse.cz Fixes: 60d3fd32a7a9 ("list_lru: introduce per-memcg lists") Signed-off-by: Jiri Slaby Acked-by: Michal Hocko Suggested-by: Vladimir Davydov Acked-by: Vladimir Davydov Reviewed-by: Shakeel Butt Cc: Johannes Weiner Cc: Raghavendra K T Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

include/linux/bitops.h: sanitize rotate primitives

2019-06-09T07:18:13Z

commit ef4d6f6b275c498f8e5626c99dbeefdc5027f843 upstream. The ror32 implementation (word >> shift) | (word << (32 - shift) has undefined behaviour if shift is outside the [1, 31] range. Similarly for the 64 bit variants. Most callers pass a compile-time constant (naturally in that range), but there's an UBSAN report that these may actually be called with a shift count of 0. Instead of special-casing that, we can make them DTRT for all values of shift while also avoiding UB. For some reason, this was already partly done for rol32 (which was well-defined for [0, 31]). gcc 8 recognizes these patterns as rotates, so for example __u32 rol32(__u32 word, unsigned int shift) { return (word << (shift & 31)) | (word >> ((-shift) & 31)); } compiles to 0000000000000020 : 20: 89 f8 mov %edi,%eax 22: 89 f1 mov %esi,%ecx 24: d3 c0 rol %cl,%eax 26: c3 retq Older compilers unfortunately do not do as well, but this only affects the small minority of users that don't pass constants. Due to integer promotions, ro[lr]8 were already well-defined for shifts in [0, 8], and ro[lr]16 were mostly well-defined for shifts in [0, 16] (only mostly - u16 gets promoted to _signed_ int, so if bit 15 is set, word << 16 is undefined). For consistency, update those as well. Link: http://lkml.kernel.org/r/20190410211906.2190-1-linux@rasmusvillemoes.dk Signed-off-by: Rasmus Villemoes Reported-by: Ido Schimmel Tested-by: Ido Schimmel Reviewed-by: Will Deacon Cc: Vadim Pasternak Cc: Andrey Ryabinin Cc: Jacek Anaszewski Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Matthias Kaehlcke Signed-off-by: Greg Kroah-Hartman

tipc: Avoid copying bytes beyond the supplied data

2019-06-09T07:18:11Z

TLV_SET is called with a data pointer and a len parameter that tells us how many bytes are pointed to by data. When invoking memcpy() we need to careful to only copy len bytes. Previously we would copy TLV_LENGTH(len) bytes which would copy an extra 4 bytes past the end of the data pointer which newer GCC versions complain about. In file included from test.c:17: In function 'TLV_SET', inlined from 'test' at test.c:186:5: /usr/include/linux/tipc_config.h:317:3: warning: 'memcpy' forming offset [33, 36] is out of the bounds [0, 32] of object 'bearer_name' with type 'char[32]' [-Warray-bounds] memcpy(TLV_DATA(tlv_ptr), data, tlv_len); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ test.c: In function 'test': test.c::161:10: note: 'bearer_name' declared here char bearer_name[TIPC_MAX_BEARER_NAME]; ^~~~~~~~~~~ We still want to ensure any padding bytes at the end are initialised, do this with a explicit memset() rather than copy bytes past the end of data. Apply the same logic to TCM_SET. Signed-off-by: Chris Packham Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

inet: switch IP ID generator to siphash

2019-06-09T07:18:10Z

[ Upstream commit df453700e8d81b1bdafdf684365ee2b9431fb702 ] According to Amit Klein and Benny Pinkas, IP ID generation is too weak and might be used by attackers. Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix()) having 64bit key and Jenkins hash is risky. It is time to switch to siphash and its 128bit keys. Signed-off-by: Eric Dumazet Reported-by: Amit Klein Reported-by: Benny Pinkas Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

HID: core: move Usage Page concatenation to Main item

2019-05-31T13:47:31Z

[ Upstream commit 58e75155009cc800005629955d3482f36a1e0eec ] As seen on some USB wireless keyboards manufactured by Primax, the HID parser was using some assumptions that are not always true. In this case it's s the fact that, inside the scope of a main item, an Usage Page will always precede an Usage. The spec is not pretty clear as 6.2.2.7 states "Any usage that follows is interpreted as a Usage ID and concatenated with the Usage Page". While 6.2.2.8 states "When the parser encounters a main item it concatenates the last declared Usage Page with a Usage to form a complete usage value." Being somewhat contradictory it was decided to match Window's implementation, which follows 6.2.2.8. In summary, the patch moves the Usage Page concatenation from the local item parsing function to the main item parsing function. Signed-off-by: Nicolas Saenz Julienne Reviewed-by: Terry Junge Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin

iio: ad_sigma_delta: Properly handle SPI bus locking vs CS assertion

2019-05-31T13:47:29Z

[ Upstream commit df1d80aee963480c5c2938c64ec0ac3e4a0df2e0 ] For devices from the SigmaDelta family we need to keep CS low when doing a conversion, since the device will use the MISO line as a interrupt to indicate that the conversion is complete. This is why the driver locks the SPI bus and when the SPI bus is locked keeps as long as a conversion is going on. The current implementation gets one small detail wrong though. CS is only de-asserted after the SPI bus is unlocked. This means it is possible for a different SPI device on the same bus to send a message which would be wrongfully be addressed to the SigmaDelta device as well. Make sure that the last SPI transfer that is done while holding the SPI bus lock de-asserts the CS signal. Signed-off-by: Lars-Peter Clausen Signed-off-by: Alexandru Ardelean Signed-off-by: Jonathan Cameron Signed-off-by: Sasha Levin

cgroup: protect cgroup->nr_(dying_)descendants by css_set_lock

2019-05-31T13:47:25Z

[ Upstream commit 4dcabece4c3a9f9522127be12cc12cc120399b2f ] The number of descendant cgroups and the number of dying descendant cgroups are currently synchronized using the cgroup_mutex. The number of descendant cgroups will be required by the cgroup v2 freezer, which will use it to determine if a cgroup is frozen (depending on total number of descendants and number of frozen descendants). It's not always acceptable to grab the cgroup_mutex, especially from quite hot paths (e.g. exit()). To avoid this, let's additionally synchronize these counters using the css_set_lock. So, it's safe to read these counters with either cgroup_mutex or css_set_lock locked, and for changing both locks should be acquired. Signed-off-by: Roman Gushchin Signed-off-by: Tejun Heo Cc: kernel-team@fb.com Signed-off-by: Sasha Levin

smpboot: Place the __percpu annotation correctly

2019-05-31T13:47:23Z

[ Upstream commit d4645d30b50d1691c26ff0f8fa4e718b08f8d3bb ] The test robot reported a wrong assignment of a per-CPU variable which it detected by using sparse and sent a report. The assignment itself is correct. The annotation for sparse was wrong and hence the report. The first pointer is a "normal" pointer and points to the per-CPU memory area. That means that the __percpu annotation has to be moved. Move the __percpu annotation to pointer which points to the per-CPU area. This change affects only the sparse tool (and is ignored by the compiler). Reported-by: kbuild test robot Signed-off-by: Sebastian Andrzej Siewior Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: f97f8f06a49fe ("smpboot: Provide infrastructure for percpu hotplug threads") Link: http://lkml.kernel.org/r/20190424085253.12178-1-bigeasy@linutronix.de Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin