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2021-04-17locking/qrwlock: Fix ordering in queued_write_lock_slowpath()Ali Saidi
While this code is executed with the wait_lock held, a reader can acquire the lock without holding wait_lock. The writer side loops checking the value with the atomic_cond_read_acquire(), but only truly acquires the lock when the compare-and-exchange is completed successfully which isn’t ordered. This exposes the window between the acquire and the cmpxchg to an A-B-A problem which allows reads following the lock acquisition to observe values speculatively before the write lock is truly acquired. We've seen a problem in epoll where the reader does a xchg while holding the read lock, but the writer can see a value change out from under it. Writer | Reader -------------------------------------------------------------------------------- ep_scan_ready_list() | |- write_lock_irq() | |- queued_write_lock_slowpath() | |- atomic_cond_read_acquire() | | read_lock_irqsave(&ep->lock, flags); --> (observes value before unlock) | chain_epi_lockless() | | epi->next = xchg(&ep->ovflist, epi); | | read_unlock_irqrestore(&ep->lock, flags); | | | atomic_cmpxchg_relaxed() | |-- READ_ONCE(ep->ovflist); | A core can order the read of the ovflist ahead of the atomic_cmpxchg_relaxed(). Switching the cmpxchg to use acquire semantics addresses this issue at which point the atomic_cond_read can be switched to use relaxed semantics. Fixes: b519b56e378ee ("locking/qrwlock: Use atomic_cond_read_acquire() when spinning in qrwlock") Signed-off-by: Ali Saidi <alisaidi@amazon.com> [peterz: use try_cmpxchg()] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Steve Capper <steve.capper@arm.com> Acked-by: Will Deacon <will@kernel.org> Acked-by: Waiman Long <longman@redhat.com> Tested-by: Steve Capper <steve.capper@arm.com>
2021-04-17sched/debug: Rename the sched_debug parameter to sched_verbosePeter Zijlstra
CONFIG_SCHED_DEBUG is the build-time Kconfig knob, the boot param sched_debug and the /debug/sched/debug_enabled knobs control the sched_debug_enabled variable, but what they really do is make SCHED_DEBUG more verbose, so rename the lot. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2021-04-16cxl/mem: Fix memory device capacity probingDan Williams
The CXL Identify Memory Device output payload emits capacity in 256MB units. The driver is treating the capacity field as bytes. This was missed because QEMU reports bytes when it should report bytes / 256MB. Fixes: 8adaf747c9f0 ("cxl/mem: Find device capabilities") Reviewed-by: Vishal Verma <vishal.l.verma@intel.com> Cc: Ben Widawsky <ben.widawsky@intel.com> Link: https://lore.kernel.org/r/161862021044.3259705.7008520073059739760.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-04-16netlink: don't call ->netlink_bind with table lock heldFlorian Westphal
When I added support to allow generic netlink multicast groups to be restricted to subscribers with CAP_NET_ADMIN I was unaware that a genl_bind implementation already existed in the past. It was reverted due to ABBA deadlock: 1. ->netlink_bind gets called with the table lock held. 2. genetlink bind callback is invoked, it grabs the genl lock. But when a new genl subsystem is (un)registered, these two locks are taken in reverse order. One solution would be to revert again and add a comment in genl referring 1e82a62fec613, "genetlink: remove genl_bind"). This would need a second change in mptcp to not expose the raw token value anymore, e.g. by hashing the token with a secret key so userspace can still associate subflow events with the correct mptcp connection. However, Paolo Abeni reminded me to double-check why the netlink table is locked in the first place. I can't find one. netlink_bind() is already called without this lock when userspace joins a group via NETLINK_ADD_MEMBERSHIP setsockopt. Same holds for the netlink_unbind operation. Digging through the history, commit f773608026ee1 ("netlink: access nlk groups safely in netlink bind and getname") expanded the lock scope. commit 3a20773beeeeade ("net: netlink: cap max groups which will be considered in netlink_bind()") ... removed the nlk->ngroups access that the lock scope extension was all about. Reduce the lock scope again and always call ->netlink_bind without the table lock. The Fixes tag should be vs. the patch mentioned in the link below, but that one got squash-merged into the patch that came earlier in the series. Fixes: 4d54cc32112d8d ("mptcp: avoid lock_fast usage in accept path") Link: https://lore.kernel.org/mptcp/20210213000001.379332-8-mathew.j.martineau@linux.intel.com/T/#u Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Xin Long <lucien.xin@gmail.com> Cc: Johannes Berg <johannes.berg@intel.com> Cc: Sean Tranchetti <stranche@codeaurora.org> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16Merge tag 'io_uring-5.12-2021-04-16' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull io_uring fix from Jens Axboe: "Fix for a potential hang at exit with SQPOLL from Pavel" * tag 'io_uring-5.12-2021-04-16' of git://git.kernel.dk/linux-block: io_uring: fix early sqd_list removal sqpoll hangs
2021-04-16lib: remove "expecting prototype" kernel-doc warningsRandy Dunlap
Fix various kernel-doc warnings in lib/ due to missing or erroneous function names. Add kernel-doc for some function parameters that was missing. Use kernel-doc "Return:" notation in earlycpio.c. Quietens the following warnings: lib/earlycpio.c:61: warning: expecting prototype for cpio_data find_cpio_data(). Prototype was for find_cpio_data() instead lib/lru_cache.c:640: warning: expecting prototype for lc_dump(). Prototype was for lc_seq_dump_details() instead lru_cache.c:90: warning: Function parameter or member 'cache' not described in 'lc_create' lib/parman.c:368: warning: expecting prototype for parman_item_del(). Prototype was for parman_item_remove() instead parman.c:309: warning: Excess function parameter 'prority' description in 'parman_prio_init' lib/radix-tree.c:703: warning: expecting prototype for __radix_tree_insert(). Prototype was for radix_tree_insert() instead radix-tree.c:180: warning: Excess function parameter 'addr' description in 'radix_tree_find_next_bit' radix-tree.c:180: warning: Excess function parameter 'size' description in 'radix_tree_find_next_bit' radix-tree.c:931: warning: Function parameter or member 'iter' not described in 'radix_tree_iter_replace' Link: https://lkml.kernel.org/r/20210411221756.15461-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Philipp Reisner <philipp.reisner@linbit.com> Cc: Lars Ellenberg <lars.ellenberg@linbit.com> Cc: Jiri Pirko <jiri@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16gcov: clang: fix clang-11+ buildJohannes Berg
With clang-11+, the code is broken due to my kvmalloc() conversion (which predated the clang-11 support code) leaving one vmalloc() in place. Fix that. Link: https://lkml.kernel.org/r/20210412214210.6e1ecca9cdc5.I24459763acf0591d5e6b31c7e3a59890d802f79c@changeid Signed-off-by: Johannes Berg <johannes.berg@intel.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16mm: ptdump: fix build failureChristophe Leroy
READ_ONCE() cannot be used for reading PTEs. Use ptep_get() instead, to avoid the following errors: CC mm/ptdump.o In file included from <command-line>: mm/ptdump.c: In function 'ptdump_pte_entry': include/linux/compiler_types.h:320:38: error: call to '__compiletime_assert_207' declared with attribute error: Unsupported access size for {READ,WRITE}_ONCE(). 320 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^ include/linux/compiler_types.h:301:4: note: in definition of macro '__compiletime_assert' 301 | prefix ## suffix(); \ | ^~~~~~ include/linux/compiler_types.h:320:2: note: in expansion of macro '_compiletime_assert' 320 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:36:2: note: in expansion of macro 'compiletime_assert' 36 | compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ | ^~~~~~~~~~~~~~~~~~ include/asm-generic/rwonce.h:49:2: note: in expansion of macro 'compiletime_assert_rwonce_type' 49 | compiletime_assert_rwonce_type(x); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mm/ptdump.c:114:14: note: in expansion of macro 'READ_ONCE' 114 | pte_t val = READ_ONCE(*pte); | ^~~~~~~~~ make[2]: *** [mm/ptdump.o] Error 1 See commit 481e980a7c19 ("mm: Allow arches to provide ptep_get()") and commit c0e1c8c22beb ("powerpc/8xx: Provide ptep_get() with 16k pages") for details. Link: https://lkml.kernel.org/r/912b349e2bcaa88939904815ca0af945740c6bd4.1618478922.git.christophe.leroy@csgroup.eu Fixes: 30d621f6723b ("mm: add generic ptdump") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Steven Price <steven.price@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16mm/mapping_dirty_helpers: guard hugepage pud's usageZack Rusin
Mapping dirty helpers have, so far, been only used on X86, but a port of vmwgfx to ARM64 exposed a problem which results in a compilation error on ARM64 systems: mm/mapping_dirty_helpers.c: In function `wp_clean_pud_entry': mm/mapping_dirty_helpers.c:172:32: error: implicit declaration of function `pud_dirty'; did you mean `pmd_dirty'? [-Werror=implicit-function-declaration] This is due to the fact that mapping_dirty_helpers code assumes that pud_dirty is always defined, which is not the case for architectures that don't define CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD. ARM64 arch is a little inconsistent when it comes to PUD hugepage helpers, e.g. it defines pud_young but not pud_dirty but regardless of that the core kernel code shouldn't assume that any of the PUD hugepage helpers are available unless CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is defined. This prevents compilation errors whenever one of the drivers is ported to new architectures. Link: https://lkml.kernel.org/r/20210409165151.694574-1-zackr@vmware.com Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Thomas Hellstrm (Intel) <thomas_os@shipmail.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16ia64: tools: remove duplicate definition of ia64_mf() on ia64John Paul Adrian Glaubitz
The ia64_mf() macro defined in tools/arch/ia64/include/asm/barrier.h is already defined in <asm/gcc_intrin.h> on ia64 which causes libbpf failing to build: CC /usr/src/linux/tools/bpf/bpftool//libbpf/staticobjs/libbpf.o In file included from /usr/src/linux/tools/include/asm/barrier.h:24, from /usr/src/linux/tools/include/linux/ring_buffer.h:4, from libbpf.c:37: /usr/src/linux/tools/include/asm/../../arch/ia64/include/asm/barrier.h:43: error: "ia64_mf" redefined [-Werror] 43 | #define ia64_mf() asm volatile ("mf" ::: "memory") | In file included from /usr/include/ia64-linux-gnu/asm/intrinsics.h:20, from /usr/include/ia64-linux-gnu/asm/swab.h:11, from /usr/include/linux/swab.h:8, from /usr/include/linux/byteorder/little_endian.h:13, from /usr/include/ia64-linux-gnu/asm/byteorder.h:5, from /usr/src/linux/tools/include/uapi/linux/perf_event.h:20, from libbpf.c:36: /usr/include/ia64-linux-gnu/asm/gcc_intrin.h:382: note: this is the location of the previous definition 382 | #define ia64_mf() __asm__ volatile ("mf" ::: "memory") | cc1: all warnings being treated as errors Thus, remove the definition from tools/arch/ia64/include/asm/barrier.h. Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16ia64: tools: remove inclusion of ia64-specific version of errno.h headerJohn Paul Adrian Glaubitz
There is no longer an ia64-specific version of the errno.h header below arch/ia64/include/uapi/asm/, so trying to build tools/bpf fails with: CC /usr/src/linux/tools/bpf/bpftool/btf_dumper.o In file included from /usr/src/linux/tools/include/linux/err.h:8, from btf_dumper.c:11: /usr/src/linux/tools/include/uapi/asm/errno.h:13:10: fatal error: ../../../arch/ia64/include/uapi/asm/errno.h: No such file or directory 13 | #include "../../../arch/ia64/include/uapi/asm/errno.h" | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ compilation terminated. Thus, just remove the inclusion of the ia64-specific errno.h so that the build will use the generic errno.h header on this target which was used there anyway as the ia64-specific errno.h was just a wrapper for the generic header. Fixes: c25f867ddd00 ("ia64: remove unneeded uapi asm-generic wrappers") Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16ia64: fix discontig.c section mismatchesRandy Dunlap
Fix IA64 discontig.c Section mismatch warnings. When CONFIG_SPARSEMEM=y and CONFIG_MEMORY_HOTPLUG=y, the functions computer_pernodesize() and scatter_node_data() should not be marked as __meminit because they are needed after init, on any memory hotplug event. Also, early_nr_cpus_node() is called by compute_pernodesize(), so early_nr_cpus_node() cannot be __meminit either. WARNING: modpost: vmlinux.o(.text.unlikely+0x1612): Section mismatch in reference from the function arch_alloc_nodedata() to the function .meminit.text:compute_pernodesize() The function arch_alloc_nodedata() references the function __meminit compute_pernodesize(). This is often because arch_alloc_nodedata lacks a __meminit annotation or the annotation of compute_pernodesize is wrong. WARNING: modpost: vmlinux.o(.text.unlikely+0x1692): Section mismatch in reference from the function arch_refresh_nodedata() to the function .meminit.text:scatter_node_data() The function arch_refresh_nodedata() references the function __meminit scatter_node_data(). This is often because arch_refresh_nodedata lacks a __meminit annotation or the annotation of scatter_node_data is wrong. WARNING: modpost: vmlinux.o(.text.unlikely+0x1502): Section mismatch in reference from the function compute_pernodesize() to the function .meminit.text:early_nr_cpus_node() The function compute_pernodesize() references the function __meminit early_nr_cpus_node(). This is often because compute_pernodesize lacks a __meminit annotation or the annotation of early_nr_cpus_node is wrong. Link: https://lkml.kernel.org/r/20210411001201.3069-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Mike Rapoport <rppt@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16ia64: remove duplicate entries in generic_defconfigRandy Dunlap
Fix ia64 generic_defconfig duplicate entries, as warned by: arch/ia64/configs/generic_defconfig: warning: override: reassigning to symbol ATA: => 58 arch/ia64/configs/generic_defconfig: warning: override: reassigning to symbol ATA_PIIX: => 59 These 2 symbols still have the same value as in the removed lines. Link: https://lkml.kernel.org/r/20210411020255.18052-1-rdunlap@infradead.org Fixes: c331649e6371 ("ia64: Use libata instead of the legacy ide driver in defconfigs") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16csky: change a Kconfig symbol name to fix e1000 build errorRandy Dunlap
e1000's #define of CONFIG_RAM_BASE conflicts with a Kconfig symbol in arch/csky/Kconfig. The symbol in e1000 has been around longer, so change arch/csky/ to use DRAM_BASE instead of RAM_BASE to remove the conflict. (although e1000 is also a 2-line change) Link: https://lkml.kernel.org/r/20210411055335.7111-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Acked-by: Guo Ren <guoren@kernel.org> Cc: Jesse Brandeburg <jesse.brandeburg@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16kasan: remove redundant config optionWalter Wu
CONFIG_KASAN_STACK and CONFIG_KASAN_STACK_ENABLE both enable KASAN stack instrumentation, but we should only need one config, so that we remove CONFIG_KASAN_STACK_ENABLE and make CONFIG_KASAN_STACK workable. see [1]. When enable KASAN stack instrumentation, then for gcc we could do no prompt and default value y, and for clang prompt and default value n. This patch fixes the following compilation warning: include/linux/kasan.h:333:30: warning: 'CONFIG_KASAN_STACK' is not defined, evaluates to 0 [-Wundef] [akpm@linux-foundation.org: fix merge snafu] Link: https://bugzilla.kernel.org/show_bug.cgi?id=210221 [1] Link: https://lkml.kernel.org/r/20210226012531.29231-1-walter-zh.wu@mediatek.com Fixes: d9b571c885a8 ("kasan: fix KASAN_STACK dependency for HW_TAGS") Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Andrey Konovalov <andreyknvl@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16kasan: fix hwasan build for gccArnd Bergmann
gcc-11 adds support for -fsanitize=kernel-hwaddress, so it becomes possible to enable CONFIG_KASAN_SW_TAGS. Unfortunately this fails to build at the moment, because the corresponding command line arguments use llvm specific syntax. Change it to use the cc-param macro instead, which works on both clang and gcc. [elver@google.com: fixup for "kasan: fix hwasan build for gcc"] Link: https://lkml.kernel.org/r/YHQZVfVVLE/LDK2v@elver.google.com Link: https://lkml.kernel.org/r/20210323124112.1229772-1-arnd@kernel.org Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Marco Elver <elver@google.com> Reviewed-by: Marco Elver <elver@google.com> Acked-by: Andrey Konovalov <andreyknvl@gmail.com> Cc: Masahiro Yamada <masahiroy@kernel.org> Cc: Michal Marek <michal.lkml@markovi.net> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16mm: eliminate "expecting prototype" kernel-doc warningsRandy Dunlap
Fix stray kernel-doc warnings in mm/ due to mis-typed or missing function names. Quietens these kernel-doc warnings: mm/mmu_gather.c:264: warning: expecting prototype for tlb_gather_mmu(). Prototype was for __tlb_gather_mmu() instead mm/oom_kill.c:180: warning: expecting prototype for Check whether unreclaimable slab amount is greater than(). Prototype was for should_dump_unreclaim_slab() instead mm/shuffle.c:155: warning: expecting prototype for shuffle_free_memory(). Prototype was for __shuffle_free_memory() instead Link: https://lkml.kernel.org/r/20210411210642.11362-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-16Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2021-04-17 The following pull-request contains BPF updates for your *net* tree. We've added 10 non-merge commits during the last 9 day(s) which contain a total of 8 files changed, 175 insertions(+), 111 deletions(-). The main changes are: 1) Fix a potential NULL pointer dereference in libbpf's xsk umem handling, from Ciara Loftus. 2) Mitigate a speculative oob read of up to map value size by tightening the masking window, from Daniel Borkmann. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16MAINTAINERS: update my emailLijun Pan
Update my email and change myself to Reviewer. Signed-off-by: Lijun Pan <lijunp213@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-16bpf: Update selftests to reflect new error statesDaniel Borkmann
Update various selftest error messages: * The 'Rx tried to sub from different maps, paths, or prohibited types' is reworked into more specific/differentiated error messages for better guidance. * The change into 'value -4294967168 makes map_value pointer be out of bounds' is due to moving the mixed bounds check into the speculation handling and thus occuring slightly later than above mentioned sanity check. * The change into 'math between map_value pointer and register with unbounded min value' is similarly due to register sanity check coming before the mixed bounds check. * The case of 'map access: known scalar += value_ptr from different maps' now loads fine given masks are the same from the different paths (despite max map value size being different). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Tighten speculative pointer arithmetic maskDaniel Borkmann
This work tightens the offset mask we use for unprivileged pointer arithmetic in order to mitigate a corner case reported by Piotr and Benedict where in the speculative domain it is possible to advance, for example, the map value pointer by up to value_size-1 out-of-bounds in order to leak kernel memory via side-channel to user space. Before this change, the computed ptr_limit for retrieve_ptr_limit() helper represents largest valid distance when moving pointer to the right or left which is then fed as aux->alu_limit to generate masking instructions against the offset register. After the change, the derived aux->alu_limit represents the largest potential value of the offset register which we mask against which is just a narrower subset of the former limit. For minimal complexity, we call sanitize_ptr_alu() from 2 observation points in adjust_ptr_min_max_vals(), that is, before and after the simulated alu operation. In the first step, we retieve the alu_state and alu_limit before the operation as well as we branch-off a verifier path and push it to the verification stack as we did before which checks the dst_reg under truncation, in other words, when the speculative domain would attempt to move the pointer out-of-bounds. In the second step, we retrieve the new alu_limit and calculate the absolute distance between both. Moreover, we commit the alu_state and final alu_limit via update_alu_sanitation_state() to the env's instruction aux data, and bail out from there if there is a mismatch due to coming from different verification paths with different states. Reported-by: Piotr Krysiuk <piotras@gmail.com> Reported-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Tested-by: Benedict Schlueter <benedict.schlueter@rub.de>
2021-04-16bpf: Move sanitize_val_alu out of op switchDaniel Borkmann
Add a small sanitize_needed() helper function and move sanitize_val_alu() out of the main opcode switch. In upcoming work, we'll move sanitize_ptr_alu() as well out of its opcode switch so this helps to streamline both. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Refactor and streamline bounds check into helperDaniel Borkmann
Move the bounds check in adjust_ptr_min_max_vals() into a small helper named sanitize_check_bounds() in order to simplify the former a bit. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Improve verifier error messages for usersDaniel Borkmann
Consolidate all error handling and provide more user-friendly error messages from sanitize_ptr_alu() and sanitize_val_alu(). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Rework ptr_limit into alu_limit and add common error pathDaniel Borkmann
Small refactor with no semantic changes in order to consolidate the max ptr_limit boundary check. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Ensure off_reg has no mixed signed bounds for all typesDaniel Borkmann
The mixed signed bounds check really belongs into retrieve_ptr_limit() instead of outside of it in adjust_ptr_min_max_vals(). The reason is that this check is not tied to PTR_TO_MAP_VALUE only, but to all pointer types that we handle in retrieve_ptr_limit() and given errors from the latter propagate back to adjust_ptr_min_max_vals() and lead to rejection of the program, it's a better place to reside to avoid anything slipping through for future types. The reason why we must reject such off_reg is that we otherwise would not be able to derive a mask, see details in 9d7eceede769 ("bpf: restrict unknown scalars of mixed signed bounds for unprivileged"). Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Move off_reg into sanitize_ptr_aluDaniel Borkmann
Small refactor to drag off_reg into sanitize_ptr_alu(), so we later on can use off_reg for generalizing some of the checks for all pointer types. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16bpf: Use correct permission flag for mixed signed bounds arithmeticDaniel Borkmann
We forbid adding unknown scalars with mixed signed bounds due to the spectre v1 masking mitigation. Hence this also needs bypass_spec_v1 flag instead of allow_ptr_leaks. Fixes: 2c78ee898d8f ("bpf: Implement CAP_BPF") Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: John Fastabend <john.fastabend@gmail.com> Acked-by: Alexei Starovoitov <ast@kernel.org>
2021-04-16blk-mq: Fix spurious debugfs directory creation during initializationSaravanan D
blk_mq_debugfs_register_sched_hctx() called from device_add_disk()->elevator_init_mq()->blk_mq_init_sched() initialization sequence does not have relevant parent directory setup and thus spuriously attempts "sched" directory creation from root mount of debugfs for every hw queue detected on the block device dmesg ... debugfs: Directory 'sched' with parent '/' already present! debugfs: Directory 'sched' with parent '/' already present! . . debugfs: Directory 'sched' with parent '/' already present! ... The parent debugfs directory for hw queues get properly setup device_add_disk()->blk_register_queue()->blk_mq_debugfs_register() ->blk_mq_debugfs_register_hctx() later in the block device initialization sequence. A simple check for debugfs_dir has been added to thwart premature debugfs directory/file creation attempts. Signed-off-by: Saravanan D <saravanand@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16cgroup: use tsk->in_iowait instead of delayacct_is_task_waiting_on_io()Chunguang Xu
If delayacct is disabled, then delayacct_is_task_waiting_on_io() always returns false, which causes the statistical value to be wrong. Perhaps tsk->in_iowait is better. Signed-off-by: Chunguang Xu <brookxu@tencent.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2021-04-16tick/broadcast: Allow late registered device to enter oneshot modeJindong Yue
The broadcast device is switched to oneshot mode when the system switches to oneshot mode. If a broadcast clock event device is registered after the system switched to oneshot mode, it will stay in periodic mode forever. Ensure that a late registered device which is selected as broadcast device is initialized in oneshot mode when the system already uses oneshot mode. [ tglx: Massage changelog ] Signed-off-by: Jindong Yue <jindong.yue@nxp.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210331083318.21794-1-jindong.yue@nxp.com
2021-04-16tick: Use tick_check_replacement() instead of open coding itWang Wensheng
The function tick_check_replacement() is the combination of tick_check_percpu() and tick_check_preferred(), but tick_check_new_device() has the same logic open coded. Use the helper to simplify the code. [ tglx: Massage changelog ] Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210326022328.3266-1-wangwensheng4@huawei.com
2021-04-16time/timecounter: Mark 1st argument of timecounter_cyc2time() as constMarc Kleine-Budde
The timecounter is not modified in this function. Mark it as const. Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lore.kernel.org/r/20210303103544.994855-1-mkl@pengutronix.de
2021-04-16mtd: core: Constify buf in mtd_write_user_prot_reg()Tudor Ambarus
The write buffer comes from user and should be const. Constify write buffer in mtd core and across all _write_user_prot_reg() users. cfi_cmdset_{0001, 0002} and onenand_base will pay the cost of an explicit cast to discard the const qualifier since the beginning, since they are using an otp_op_t function prototype that is used for both reads and writes. mtd_dataflash and SPI NOR will benefit of the const buffer because they are using different paths for writes and reads. Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/linux-mtd/20210403060931.7119-1-tudor.ambarus@microchip.com
2021-04-16Merge tag 'riscv-for-linus-5.12-rc8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: "A handful of fixes: - a fix to properly select SPARSEMEM_STATIC on rv32 - a few fixes to kprobes I don't generally like sending stuff this late, but these all seem pretty safe" * tag 'riscv-for-linus-5.12-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: keep interrupts disabled for BREAKPOINT exception riscv: kprobes/ftrace: Add recursion protection to the ftrace callback riscv: add do_page_fault and do_trap_break into the kprobes blacklist riscv: Fix spelling mistake "SPARSEMEM" to "SPARSMEM"
2021-04-16perf/amd/uncore: Fix sysfs type mismatchNathan Chancellor
dev_attr_show() calls the __uncore_*_show() functions via an indirect call but their type does not currently match the type of the show() member in 'struct device_attribute', resulting in a Control Flow Integrity violation. $ cat /sys/devices/amd_l3/format/umask config:8-15 $ dmesg | grep "CFI failure" [ 1258.174653] CFI failure (target: __uncore_umask_show...): Update the type in the DEFINE_UNCORE_FORMAT_ATTR macro to match 'struct device_attribute' so that there is no more CFI violation. Fixes: 06f2c24584f3 ("perf/amd/uncore: Prepare to scale for more attributes that vary per family") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210415001112.3024673-2-nathan@kernel.org
2021-04-16x86/events/amd/iommu: Fix sysfs type mismatchNathan Chancellor
dev_attr_show() calls _iommu_event_show() via an indirect call but _iommu_event_show()'s type does not currently match the type of the show() member in 'struct device_attribute', resulting in a Control Flow Integrity violation. $ cat /sys/devices/amd_iommu_1/events/mem_dte_hit csource=0x0a $ dmesg | grep "CFI failure" [ 3526.735140] CFI failure (target: _iommu_event_show...): Change _iommu_event_show() and 'struct amd_iommu_event_desc' to 'struct device_attribute' so that there is no more CFI violation. Fixes: 7be6296fdd75 ("perf/x86/amd: AMD IOMMU Performance Counter PERF uncore PMU implementation") Signed-off-by: Nathan Chancellor <nathan@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210415001112.3024673-1-nathan@kernel.org
2021-04-16perf core: Add PERF_COUNT_SW_CGROUP_SWITCHES eventNamhyung Kim
This patch adds a new software event to count context switches involving cgroup switches. So it's counted only if cgroups of previous and next tasks are different. Note that it only checks the cgroups in the perf_event subsystem. For cgroup v2, it shouldn't matter anyway. One can argue that we can do this by using existing sched_switch event with eBPF. But some systems might not have eBPF for some reason so I'd like to add this as a simple way. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210210083327.22726-2-namhyung@kernel.org
2021-04-16perf core: Factor out __perf_sw_event_schedNamhyung Kim
In some cases, we need to check more than whether the software event is enabled. So split the condition check and the actual event handling. This is a preparation for the next change. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20210210083327.22726-1-namhyung@kernel.org
2021-04-16Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fix from Catalin Marinas: "Fix kernel compilation when using the LLVM integrated assembly. A recent commit (2decad92f473, "arm64: mte: Ensure TIF_MTE_ASYNC_FAULT is set atomically") broke the kernel build when using the LLVM integrated assembly (only noticeable with clang-12 as MTE is not supported by earlier versions and the code in question not compiled). The Fixes: tag in the commit refers to the original patch introducing subsections for the alternative code sequences" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: alternatives: Move length validation in alternative_{insn, endif}
2021-04-16io_uring: fix merge error for async resubmitJens Axboe
A hand-edit while applying this patch on top of a new base resulted in a reverted check for re-issue, resulting in spurious -EAGAIN errors. Fixes: 8c130827f417 ("io_uring: don't alter iopoll reissue fail ret code") Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16io_uring: tie req->apoll to request lifetimeJens Axboe
We manage these separately right now, just tie it to the request lifetime and make it be part of the usual REQ_F_NEED_CLEANUP logic. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16io_uring: put flag checking for needing req cleanup in one spotJens Axboe
We have this in two spots right now, which is a bit fragile. In preparation for moving REQ_F_POLLED cleanup into the same spot, move the check into a separate helper so we only have it once. Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-16drm/bridge: lt8912b: fix incorrect handling of of_* return valuesAdrien Grassein
A static analysis shows several issues in the driver code at probing time. DT parsing errors were bad handled and could lead to bugs: - Bad error detection; - Bad release of resources Fixes: 30e2ae943c26 ("drm/bridge: Introduce LT8912B DSI to HDMI bridge") Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Suggested-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Adrien Grassein <adrien.grassein@gmail.com> Reviewed-by: Andrzej Hajda <a.hajda@samsung.com> Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210415183639.1487-1-rdunlap@infradead.org Signed-off-by: Robert Foss <robert.foss@linaro.org>
2021-04-16sched,fair: Alternative sched_slice()Peter Zijlstra
The current sched_slice() seems to have issues; there's two possible things that could be improved: - the 'nr_running' used for __sched_period() is daft when cgroups are considered. Using the RQ wide h_nr_running seems like a much more consistent number. - (esp) cgroups can slice it real fine, which makes for easy over-scheduling, ensure min_gran is what the name says. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210412102001.611897312@infradead.org
2021-04-16sched: Move /proc/sched_debug to debugfsPeter Zijlstra
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210412102001.548833671@infradead.org
2021-04-16sched,debug: Convert sysctl sched_domains to debugfsPeter Zijlstra
Stop polluting sysctl, move to debugfs for SCHED_DEBUG stuff. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/YHgB/s4KCBQ1ifdm@hirez.programming.kicks-ass.net
2021-04-16debugfs: Implement debugfs_create_str()Peter Zijlstra
Implement debugfs_create_str() to easily display names and such in debugfs. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210412102001.415407080@infradead.org
2021-04-16sched,preempt: Move preempt_dynamic to debug.cPeter Zijlstra
Move the #ifdef SCHED_DEBUG bits to kernel/sched/debug.c in order to collect all the debugfs bits. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210412102001.353833279@infradead.org
2021-04-16sched: Move SCHED_DEBUG sysctl to debugfsPeter Zijlstra
Stop polluting sysctl with undocumented knobs that really are debug only, move them all to /debug/sched/ along with the existing /debug/sched_* files that already exist. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Tested-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20210412102001.287610138@infradead.org