aboutsummaryrefslogtreecommitdiffstats
path: root/tools (follow)
AgeCommit message (Collapse)AuthorFilesLines
2019-07-18objtool: Support conditional retpolinesJosh Poimboeuf2-2/+11
A Clang-built kernel is showing the following warning: arch/x86/kernel/platform-quirks.o: warning: objtool: x86_early_init_platform_quirks()+0x84: unreachable instruction That corresponds to this code: 7e: 0f 85 00 00 00 00 jne 84 <x86_early_init_platform_quirks+0x84> 80: R_X86_64_PC32 __x86_indirect_thunk_r11-0x4 84: c3 retq This is a conditional retpoline sibling call, which is now possible thanks to retpolines. Objtool hasn't seen that before. It's incorrectly interpreting the conditional jump as an unconditional dynamic jump. Reported-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/30d4c758b267ef487fb97e6ecb2f148ad007b554.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Convert insn type to enumJosh Poimboeuf4-26/+20
This makes it easier to add new instruction types. Also it's hopefully more robust since the compiler should warn about out-of-range enums. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/0740e96af0d40e54cfd6a07bf09db0fbd10793cd.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Fix seg fault on bad switch table entryJosh Poimboeuf1-1/+1
In one rare case, Clang generated the following code: 5ca: 83 e0 21 and $0x21,%eax 5cd: b9 04 00 00 00 mov $0x4,%ecx 5d2: ff 24 c5 00 00 00 00 jmpq *0x0(,%rax,8) 5d5: R_X86_64_32S .rodata+0x38 which uses the corresponding jump table relocations: 000000000038 000200000001 R_X86_64_64 0000000000000000 .text + 834 000000000040 000200000001 R_X86_64_64 0000000000000000 .text + 5d9 000000000048 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000050 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000058 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000060 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000068 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000070 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000078 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000080 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000088 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000090 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000098 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000a0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000a8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000b0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000b8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000c0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000c8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000d0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000d8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000e0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000e8 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000f0 000200000001 R_X86_64_64 0000000000000000 .text + b96 0000000000f8 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000100 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000108 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000110 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000118 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000120 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000128 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000130 000200000001 R_X86_64_64 0000000000000000 .text + b96 000000000138 000200000001 R_X86_64_64 0000000000000000 .text + 82f 000000000140 000200000001 R_X86_64_64 0000000000000000 .text + 828 Since %eax was masked with 0x21, only the first two and the last two entries are possible. Objtool doesn't actually emulate all the code, so it isn't smart enough to know that all the middle entries aren't reachable. They point to the NOP padding area after the end of the function, so objtool seg faulted when it tried to dereference a NULL insn->func. After this fix, objtool still gives an "unreachable" error because it stops reading the jump table when it encounters the bad addresses: /home/jpoimboe/objtool-tests/adm1275.o: warning: objtool: adm1275_probe()+0x828: unreachable instruction While the above code is technically correct, it's very wasteful of memory -- it uses 34 jump table entries when only 4 are needed. It's also not possible for objtool to validate this type of switch table because the unused entries point outside the function and objtool has no way of determining if that's intentional. Hopefully the Clang folks can fix it. Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/a9db88eec4f1ca089e040989846961748238b6d8.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Support repeated uses of the same C jump tableJann Horn3-25/+30
This fixes objtool for both a GCC issue and a Clang issue: 1) GCC issue: kernel/bpf/core.o: warning: objtool: ___bpf_prog_run()+0x8d5: sibling call from callable instruction with modified stack frame With CONFIG_RETPOLINE=n, GCC is doing the following optimization in ___bpf_prog_run(). Before: select_insn: jmp *jumptable(,%rax,8) ... ALU64_ADD_X: ... jmp select_insn ALU_ADD_X: ... jmp select_insn After: select_insn: jmp *jumptable(, %rax, 8) ... ALU64_ADD_X: ... jmp *jumptable(, %rax, 8) ALU_ADD_X: ... jmp *jumptable(, %rax, 8) This confuses objtool. It has never seen multiple indirect jump sites which use the same jump table. For GCC switch tables, the only way of detecting the size of a table is by continuing to scan for more tables. The size of the previous table can only be determined after another switch table is found, or when the scan reaches the end of the function. That logic was reused for C jump tables, and was based on the assumption that each jump table only has a single jump site. The above optimization breaks that assumption. 2) Clang issue: drivers/usb/misc/sisusbvga/sisusb.o: warning: objtool: sisusb_write_mem_bulk()+0x588: can't find switch jump table With clang 9, code can be generated where a function contains two indirect jump instructions which use the same switch table. The fix is the same for both issues: split the jump table parsing into two passes. In the first pass, locate the heads of all switch tables for the function and mark their locations. In the second pass, parse the switch tables and add them. Fixes: e55a73251da3 ("bpf: Fix ORC unwinding in non-JIT BPF code") Reported-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/e995befaada9d4d8b2cf788ff3f566ba900d2b4d.1563413318.git.jpoimboe@redhat.com Co-developed-by: Josh Poimboeuf <jpoimboe@redhat.com>
2019-07-18objtool: Refactor jump table codeJosh Poimboeuf3-40/+46
Now that C jump tables are supported, call them "jump tables" instead of "switch tables". Also rename some other variables, add comments, and simplify the code flow a bit. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/cf951b0c0641628e0b9b81f7ceccd9bcabcb4bd8.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Refactor sibling call detection logicJosh Poimboeuf1-32/+33
Simplify the sibling call detection logic a bit. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/8357dbef9e7f5512e76bf83a76c81722fc09eb5e.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Do frame pointer check before dead end checkJosh Poimboeuf1-9/+9
Even calls to __noreturn functions need the frame pointer setup first. Such functions often dump the stack. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/aed62fbd60e239280218be623f751a433658e896.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Change dead_end_function() to return booleanJosh Poimboeuf1-22/+14
dead_end_function() can no longer return an error. Simplify its interface by making it return boolean. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/9e6679610768fb6e6c51dca23f7d4d0c03b0c910.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Warn on zero-length functionsJosh Poimboeuf1-0/+6
All callable functions should have an ELF size. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/03d429c4fa87829c61c5dc0e89652f4d9efb62f1.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Refactor function alias logicJosh Poimboeuf2-8/+10
- Add an alias check in validate_functions(). With this change, aliases no longer need uaccess_safe set. - Add an alias check in decode_instructions(). With this change, the "if (!insn->func)" check is no longer needed. - Don't create aliases for zero-length functions, as it can have unexpected results. The next patch will spit out a warning for zero-length functions anyway. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/26a99c31426540f19c9a58b9e10727c385a147bc.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Track original function across branchesJosh Poimboeuf1-16/+12
If 'insn->func' is NULL, objtool skips some important checks, including sibling call validation. So if some .fixup code does an invalid sibling call, objtool ignores it. Treat all code branches (including alts) as part of the original function by keeping track of the original func value from validate_functions(). This improves the usefulness of some clang function fallthrough warnings, and exposes some additional kernel bugs in the process. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/505df630f33c9717e1ccde6e4b64c5303135c25f.1563413318.git.jpoimboe@redhat.com
2019-07-18objtool: Add mcsafe_handle_tail() to the uaccess safe listJosh Poimboeuf1-0/+1
After an objtool improvement, it's reporting that __memcpy_mcsafe() is calling mcsafe_handle_tail() with AC=1: arch/x86/lib/memcpy_64.o: warning: objtool: .fixup+0x13: call to mcsafe_handle_tail() with UACCESS enabled arch/x86/lib/memcpy_64.o: warning: objtool: __memcpy_mcsafe()+0x34: (alt) arch/x86/lib/memcpy_64.o: warning: objtool: __memcpy_mcsafe()+0xb: (branch) arch/x86/lib/memcpy_64.o: warning: objtool: __memcpy_mcsafe()+0x0: <=== (func) mcsafe_handle_tail() is basically an extension of __memcpy_mcsafe(), so AC=1 is supposed to be set. Add mcsafe_handle_tail() to the uaccess safe list. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/035c38f7eac845281d3c3d36749144982e06e58c.1563413318.git.jpoimboe@redhat.com
2019-07-18Merge tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-traceLinus Torvalds9-16/+101
Pull tracing updates from Steven Rostedt: "The main changes in this release include: - Add user space specific memory reading for kprobes - Allow kprobes to be executed earlier in boot The rest are mostly just various clean ups and small fixes" * tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits) tracing: Make trace_get_fields() global tracing: Let filter_assign_type() detect FILTER_PTR_STRING tracing: Pass type into tracing_generic_entry_update() ftrace/selftest: Test if set_event/ftrace_pid exists before writing ftrace/selftests: Return the skip code when tracing directory not configured in kernel tracing/kprobe: Check registered state using kprobe tracing/probe: Add trace_event_call accesses APIs tracing/probe: Add probe event name and group name accesses APIs tracing/probe: Add trace flag access APIs for trace_probe tracing/probe: Add trace_event_file access APIs for trace_probe tracing/probe: Add trace_event_call register API for trace_probe tracing/probe: Add trace_probe init and free functions tracing/uprobe: Set print format when parsing command tracing/kprobe: Set print format right after parsed command kprobes: Fix to init kprobes in subsys_initcall tracepoint: Use struct_size() in kmalloc() ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS ftrace: Enable trampoline when rec count returns back to one tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline tracing: Make a separate config for trace event self tests ...
2019-07-18Merge branch 'x86/debug' into core/urgentThomas Gleixner1-7/+20
Pick up the two pending objtool patches as the next round of objtool fixes depend on them.
2019-07-18objtool: Rename elf_open() to prevent conflict with libelf from elftoolchainMichael Forney3-3/+3
The elftoolchain version of libelf has a function named elf_open(). The function name isn't quite accurate anyway, since it also reads all the ELF data. Rename it to elf_read(), which is more accurate. [ jpoimboe: rename to elf_read(); write commit description ] Signed-off-by: Michael Forney <mforney@mforney.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/7ce2d1b35665edf19fd0eb6fbc0b17b81a48e62f.1562793604.git.jpoimboe@redhat.com
2019-07-18objtool: Use Elf_Scn typedef instead of assuming struct nameMichael Forney1-1/+1
The libelf implementation might use a different struct name, and the Elf_Scn typedef is already used throughout the rest of objtool. Signed-off-by: Michael Forney <mforney@mforney.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/d270e1be2835fc2a10acf67535ff2ebd2145bf43.1562793448.git.jpoimboe@redhat.com
2019-07-18Merge tag 'perf-core-for-mingo-5.3-20190715' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgentThomas Gleixner20-142/+1029
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: perf db-export: Adrian Hunter: - Improvements in how COMM details are exported to databases for post processing and use in the sql-viewer.py UI. - Export switch events to the database. BPF: Arnaldo Carvalho de Melo: - Bump rlimit(MEMLOCK) for 'perf test bpf' and 'perf trace', just like selftests/bpf/bpf_rlimit.h do, which makes errors due to exhaustion of this limit, which are kinda cryptic (EPERM sometimes) less frequent. perf version: Ravi Bangoria: - Fix segfault due to missing OPT_END(), noticed on PowerPC. perf vendor events: Thomas Richter: - Add JSON files for IBM s/390 machine type 8561. perf cs-etm (ARM): YueHaibing: - Fix two cases of error returns not bing done properly: Invalid ERR_PTR() use and loss of propagation error codes.
2019-07-17selftests: add a test case for rp_filterCong Wang1-1/+34
Add a test case to simulate the loopback packet case fixed in the previous patch. This test gets passed after the fix: IPv4 rp_filter tests TEST: rp_filter passes local packets [ OK ] TEST: rp_filter passes loopback packets [ OK ] Cc: David Ahern <dsahern@gmail.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-18kbuild: create *.mod with full directory path and remove MODVERDIRMasahiro Yamada1-2/+2
While descending directories, Kbuild produces objects for modules, but do not link final *.ko files; it is done in the modpost. To keep track of modules, Kbuild creates a *.mod file in $(MODVERDIR) for every module it is building. Some post-processing steps read the necessary information from *.mod files. This avoids descending into directories again. This mechanism was introduced in 2003 or so. Later, commit 551559e13af1 ("kbuild: implement modules.order") added modules.order. So, we can simply read it out to know all the modules with directory paths. This is easier than parsing the first line of *.mod files. $(MODVERDIR) has a flat directory structure, that is, *.mod files are named only with base names. This is based on the assumption that the module name is unique across the tree. This assumption is really fragile. Stephen Rothwell reported a race condition caused by a module name conflict: https://lkml.org/lkml/2019/5/13/991 In parallel building, two different threads could write to the same $(MODVERDIR)/*.mod simultaneously. Non-unique module names are the source of all kind of troubles, hence commit 3a48a91901c5 ("kbuild: check uniqueness of module names") introduced a new checker script. However, it is still fragile in the build system point of view because this race happens before scripts/modules-check.sh is invoked. If it happens again, the modpost will emit unclear error messages. To fix this issue completely, create *.mod with full directory path so that two threads never attempt to write to the same file. $(MODVERDIR) is no longer needed. Since modules with directory paths are listed in modules.order, Kbuild is still able to find *.mod files without additional descending. I also killed cmd_secanalysis; scripts/mod/sumversion.c computes MD4 hash for modules with MODULE_VERSION(). When CONFIG_DEBUG_SECTION_MISMATCH=y, it occurs not only in the modpost stage, but also during directory descending, where sumversion.c may parse stale *.mod files. It would emit 'No such file or directory' warning when an object consisting a module is renamed, or when a single-obj module is turned into a multi-obj module or vice versa. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Nicolas Pitre <nico@fluxnic.net>
2019-07-17Merge branch 'akpm' (patches from Andrew)Linus Torvalds8-7/+432
Merge more updates from Andrew Morton: "VM: - z3fold fixes and enhancements by Henry Burns and Vitaly Wool - more accurate reclaimed slab caches calculations by Yafang Shao - fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by Christoph Hellwig - !CONFIG_MMU fixes by Christoph Hellwig - new novmcoredd parameter to omit device dumps from vmcore, by Kairui Song - new test_meminit module for testing heap and pagealloc initialization, by Alexander Potapenko - ioremap improvements for huge mappings, by Anshuman Khandual - generalize kprobe page fault handling, by Anshuman Khandual - device-dax hotplug fixes and improvements, by Pavel Tatashin - enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V - add pte_devmap() support for arm64, by Robin Murphy - unify locked_vm accounting with a helper, by Daniel Jordan - several misc fixes core/lib: - new typeof_member() macro including some users, by Alexey Dobriyan - make BIT() and GENMASK() available in asm, by Masahiro Yamada - changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better code generation, by Alexey Dobriyan - rbtree code size optimizations, by Michel Lespinasse - convert struct pid count to refcount_t, by Joel Fernandes get_maintainer.pl: - add --no-moderated switch to skip moderated ML's, by Joe Perches misc: - ptrace PTRACE_GET_SYSCALL_INFO interface - coda updates - gdb scripts, various" [ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ] * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (100 commits) fs/select.c: use struct_size() in kmalloc() mm: add account_locked_vm utility function arm64: mm: implement pte_devmap support mm: introduce ARCH_HAS_PTE_DEVMAP mm: clean up is_device_*_page() definitions mm/mmap: move common defines to mman-common.h mm: move MAP_SYNC to asm-generic/mman-common.h device-dax: "Hotremove" persistent memory that is used like normal RAM mm/hotplug: make remove_memory() interface usable device-dax: fix memory and resource leak if hotplug fails include/linux/lz4.h: fix spelling and copy-paste errors in documentation ipc/mqueue.c: only perform resource calculation if user valid include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures scripts/gdb: add helpers to find and list devices scripts/gdb: add lx-genpd-summary command drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl kernel/pid.c: convert struct pid count to refcount_t drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining() select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR ...
2019-07-16selftests/ptrace: add a test case for PTRACE_GET_SYSCALL_INFODmitry V. Levin3-1/+273
Check whether PTRACE_GET_SYSCALL_INFO semantics implemented in the kernel matches userspace expectations. [akpm@linux-foundation.org: coding-style fixes] Link: http://lkml.kernel.org/r/20190510152852.GG28558@altlinux.org Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Acked-by: Shuah Khan <shuah@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Elvira Khabirova <lineprinter@altlinux.org> Cc: Eugene Syromyatnikov <esyr@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Greentime Hu <greentime@andestech.com> Cc: Helge Deller <deller@gmx.de> [parisc] Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: James Hogan <jhogan@kernel.org> Cc: kbuild test robot <lkp@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Vincent Chen <deanbo422@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16ptrace: add PTRACE_GET_SYSCALL_INFO requestElvira Khabirova1-4/+9
PTRACE_GET_SYSCALL_INFO is a generic ptrace API that lets ptracer obtain details of the syscall the tracee is blocked in. There are two reasons for a special syscall-related ptrace request. Firstly, with the current ptrace API there are cases when ptracer cannot retrieve necessary information about syscalls. Some examples include: * The notorious int-0x80-from-64-bit-task issue. See [1] for details. In short, if a 64-bit task performs a syscall through int 0x80, its tracer has no reliable means to find out that the syscall was, in fact, a compat syscall, and misidentifies it. * Syscall-enter-stop and syscall-exit-stop look the same for the tracer. Common practice is to keep track of the sequence of ptrace-stops in order not to mix the two syscall-stops up. But it is not as simple as it looks; for example, strace had a (just recently fixed) long-standing bug where attaching strace to a tracee that is performing the execve system call led to the tracer identifying the following syscall-exit-stop as syscall-enter-stop, which messed up all the state tracking. * Since the introduction of commit 84d77d3f06e7 ("ptrace: Don't allow accessing an undumpable mm"), both PTRACE_PEEKDATA and process_vm_readv become unavailable when the process dumpable flag is cleared. On such architectures as ia64 this results in all syscall arguments being unavailable for the tracer. Secondly, ptracers also have to support a lot of arch-specific code for obtaining information about the tracee. For some architectures, this requires a ptrace(PTRACE_PEEKUSER, ...) invocation for every syscall argument and return value. ptrace(2) man page: long ptrace(enum __ptrace_request request, pid_t pid, void *addr, void *data); ... PTRACE_GET_SYSCALL_INFO Retrieve information about the syscall that caused the stop. The information is placed into the buffer pointed by "data" argument, which should be a pointer to a buffer of type "struct ptrace_syscall_info". The "addr" argument contains the size of the buffer pointed to by "data" argument (i.e., sizeof(struct ptrace_syscall_info)). The return value contains the number of bytes available to be written by the kernel. If the size of data to be written by the kernel exceeds the size specified by "addr" argument, the output is truncated. [ldv@altlinux.org: selftests/seccomp/seccomp_bpf: update for PTRACE_GET_SYSCALL_INFO] Link: http://lkml.kernel.org/r/20190708182904.GA12332@altlinux.org Link: http://lkml.kernel.org/r/20190510152842.GF28558@altlinux.org Signed-off-by: Elvira Khabirova <lineprinter@altlinux.org> Co-developed-by: Dmitry V. Levin <ldv@altlinux.org> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Andy Lutomirski <luto@kernel.org> Cc: Eugene Syromyatnikov <esyr@redhat.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Greentime Hu <greentime@andestech.com> Cc: Helge Deller <deller@gmx.de> [parisc] Cc: James E.J. Bottomley <jejb@parisc-linux.org> Cc: James Hogan <jhogan@kernel.org> Cc: kbuild test robot <lkp@intel.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Burton <paul.burton@mips.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Vincent Chen <deanbo422@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16proc: test /proc/sysvipc vs setns(CLONE_NEWIPC)Alexey Dobriyan3-0/+135
I thought that /proc/sysvipc has the same bug as /proc/net commit 1fde6f21d90f8ba5da3cb9c54ca991ed72696c43 proc: fix /proc/net/* after setns(2) However, it doesn't! /proc/sysvipc files do get_ipc_ns(current->nsproxy->ipc_ns); in their open() hook and avoid the problem. Keep the test, maybe /proc/sysvipc will become broken someday :-\ Link: http://lkml.kernel.org/r/20190706180146.GA21015@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16tools/testing/selftests/proc/proc-pid-vm.c: hide "segfault at ffffffffff600000" dmesg spamAlexey Dobriyan1-2/+15
Test tries to access vsyscall page and if it doesn't exist gets SIGSEGV which can spam into dmesg. However the segfault happens by design. Handle it and carry information via exit code to parent. Link: http://lkml.kernel.org/r/20190524181256.GA2260@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16selftests/bpf: fix perf_buffer on s390Ilya Leoshkevich3-17/+11
perf_buffer test fails for exactly the same reason test_attach_probe used to fail: different nanosleep syscall kprobe name. Reuse the test_attach_probe fix. Fixes: ee5cf82ce04a ("selftests/bpf: test perf buffer API") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-16selftests/bpf: structure test_{progs, maps, verifier} test runners uniformlyAndrii Nakryiko1-14/+10
It's easier to follow the logic if it's structured the same. There is just slight difference between test_progs/test_maps and test_verifier. test_verifier's verifier/*.c files are not really compilable C files (they are more of include headers), so they can't be specified as explicit dependencies of test_verifier. Cc: Alexei Starovoitov <ast@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-16selftests/bpf: fix test_verifier/test_maps make dependenciesAndrii Nakryiko1-3/+3
e46fc22e60a4 ("selftests/bpf: make directory prerequisites order-only") exposed existing problem in Makefile for test_verifier and test_maps tests: their dependency on auto-generated header file with a list of all tests wasn't recorded explicitly. This patch fixes these issues. Fixes: 51a0e301a563 ("bpf: Add BPF_MAP_TYPE_SK_STORAGE test to test_maps") Fixes: 6b7b6995c43e ("selftests: bpf: tests.h should depend on .c files, not the output") Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Stanislav Fomichev <sdf@google.com> Cc: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-16Merge tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediaLinus Torvalds2-2/+2
Pull rst conversion of docs from Mauro Carvalho Chehab: "As agreed with Jon, I'm sending this big series directly to you, c/c him, as this series required a special care, in order to avoid conflicts with other trees" * tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (77 commits) docs: kbuild: fix build with pdf and fix some minor issues docs: block: fix pdf output docs: arm: fix a breakage with pdf output docs: don't use nested tables docs: gpio: add sysfs interface to the admin-guide docs: locking: add it to the main index docs: add some directories to the main documentation index docs: add SPDX tags to new index files docs: add a memory-devices subdir to driver-api docs: phy: place documentation under driver-api docs: serial: move it to the driver-api docs: driver-api: add remaining converted dirs to it docs: driver-api: add xilinx driver API documentation docs: driver-api: add a series of orphaned documents docs: admin-guide: add a series of orphaned documents docs: cgroup-v1: add it to the admin-guide book docs: aoe: add it to the driver-api book docs: add some documentation dirs to the driver-api book docs: driver-model: move it to the driver-api book docs: lp855x-driver.rst: add it to the driver-api book ...
2019-07-16ftrace/selftest: Test if set_event/ftrace_pid exists before writingSteven Rostedt (VMware)1-2/+2
While testing on a very old kernel (3.5), the tests failed because the write to set_event_pid in the setup code, did not exist. The tests themselves could pass, but the setup failed causing an error. Other files test for existance before writing to them. Do the same for set_event_pid and set_ftrace_pid. Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16ftrace/selftests: Return the skip code when tracing directory not configured in kernelSteven Rostedt (VMware)1-6/+32
If the kernel is not configured with ftrace enabled, the ftracetest selftests should return the error code of "4" as that is the kselftests "skip" code, and not "1" which means an error. To determine if ftrace is enabled, first the newer "tracefs" is searched for in /proc/mounts. If it is not found, then "debugfs" is searched for (as old kernels do not have tracefs). If that is not found, an attempt to mount the tracefs or debugfs is performed. This is done by seeing first if the /sys/kernel/tracing directory exists. If it does than tracefs is configured in the kernel and an attempt to mount it is performed. If /sys/kernel/tracing does not exist, then /sys/kernel/debug is tested to see if that directory exists. If it does, then an attempt to mount debugfs on that directory is performed. If it does not exist, then debugfs is not configured in the running kernel and the test exits with the skip code. If either mount fails, then a normal error is returned as they do exist in the kernel but something went wrong to mount them. This changes the test to always try the tracefs file system first as it has been in the kernel for some time now and it is better to test it if it is available instead of always testing debugfs. Link: http://lkml.kernel.org/r/20190702062358.7330-1-po-hsu.lin@canonical.com Reported-by: Po-Hsu Lin <po-hsu.lin@canonical.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-16Merge tag 'safesetid-5.3' of git://github.com/micah-morton/linuxLinus Torvalds1-11/+7
Pull safesetid updates from Micah Morton: "These changes from Jann Horn fix a couple issues in the recently added SafeSetID LSM: - There was a simple logic bug in one of the hooks for the LSM where the code was incorrectly returning early in some cases before all security checks had been passed. - There was a more high level issue with how this LSM gets configured that could allow for a program to bypass the security restrictions by switching to an allowed UID and then again to any other UID on the system if the target UID of the first transition is unconstrained on the system. Luckily this is an easy fix that we now enforce at the time the LSM gets configured. There are also some changes from Jann that make policy updates for this LSM atomic. Kees Cook, Jann and myself have reviewed these changes and they look good from our point of view" * tag 'safesetid-5.3' of git://github.com/micah-morton/linux: LSM: SafeSetID: fix use of literal -1 in capable hook LSM: SafeSetID: verify transitive constrainedness LSM: SafeSetID: add read handler LSM: SafeSetID: rewrite userspace API to atomic updates LSM: SafeSetID: fix userns handling in securityfs LSM: SafeSetID: refactor policy parsing LSM: SafeSetID: refactor safesetid_security_capable() LSM: SafeSetID: refactor policy hash table LSM: SafeSetID: fix check for setresuid(new1, new2, new3) LSM: SafeSetID: fix pr_warn() to include newline
2019-07-16libbpf: fix another GCC8 warning for strncpyAndrii Nakryiko1-1/+2
Similar issue was fixed in cdfc7f888c2a ("libbpf: fix GCC8 warning for strncpy") already. This one was missed. Fixing now. Cc: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-16selftests/bpf: skip nmi test when perf hw events are disabledIlya Leoshkevich1-1/+32
Some setups (e.g. virtual machines) might run with hardware perf events disabled. If this is the case, skip the test_send_signal_nmi test. Add a separate test involving a software perf event. This allows testing the perf event path regardless of hardware perf event support. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-16selftests/bpf: fix "alu with different scalars 1" on s390Ilya Leoshkevich1-1/+1
BPF_LDX_MEM is used to load the least significant byte of the retrieved test_val.index, however, on big-endian machines it ends up retrieving the most significant byte. Change the test to load the whole int in order to make it endianness-independent. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-15Merge tag 'pci-v5.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pciLinus Torvalds2-7/+6
Pull PCI updates from Bjorn Helgaas: "Enumeration changes: - Evaluate PCI Boot Configuration _DSM to learn if firmware wants us to preserve its resource assignments (Benjamin Herrenschmidt) - Simplify resource distribution (Nicholas Johnson) - Decode 32 GT/s link speed (Gustavo Pimentel) Virtualization: - Fix incorrect caching of VF config space size (Alex Williamson) - Fix VF driver probing sysfs knobs (Alex Williamson) Peer-to-peer DMA: - Fix dma_virt_ops check (Logan Gunthorpe) Altera host bridge driver: - Allow building as module (Ley Foon Tan) Armada 8K host bridge driver: - add PHYs support (Miquel Raynal) DesignWare host bridge driver: - Export APIs to support removable loadable module (Vidya Sagar) - Enable Relaxed Ordering erratum workaround only on Tegra20 & Tegra30 (Vidya Sagar) Hyper-V host bridge driver: - Fix use-after-free in eject (Dexuan Cui) Mobiveil host bridge driver: - Clean up and fix many issues, including non-identify mapped windows, 64-bit windows, multi-MSI, class code, INTx clearing (Hou Zhiqiang) Qualcomm host bridge driver: - Use clk bulk API for 2.4.0 controllers (Bjorn Andersson) - Add QCS404 support (Bjorn Andersson) - Assert PERST for at least 100ms (Niklas Cassel) R-Car host bridge driver: - Add r8a774a1 DT support (Biju Das) Tegra host bridge driver: - Add support for Gen2, opportunistic UpdateFC and ACK (PCIe protocol details) AER, GPIO-based PERST# (Manikanta Maddireddy) - Fix many issues, including power-on failure cases, interrupt masking in suspend, UPHY settings, AFI dynamic clock gating, pending DLL transactions (Manikanta Maddireddy) Xilinx host bridge driver: - Fix NWL Multi-MSI programming (Bharat Kumar Gogada) Endpoint support: - Fix 64bit BAR support (Alan Mikhak) - Fix pcitest build issues (Alan Mikhak, Andy Shevchenko) Bug fixes: - Fix NVIDIA GPU multi-function power dependencies (Abhishek Sahu) - Fix NVIDIA GPU HDA enablement issue (Lukas Wunner) - Ignore lockdep for sysfs "remove" (Marek Vasut) Misc: - Convert docs to reST (Changbin Du, Mauro Carvalho Chehab)" * tag 'pci-v5.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (107 commits) PCI: Enable NVIDIA HDA controllers tools: PCI: Fix installation when `make tools/pci_install` PCI: dwc: pci-dra7xx: Fix compilation when !CONFIG_GPIOLIB PCI: Fix typos and whitespace errors PCI: mobiveil: Fix INTx interrupt clearing in mobiveil_pcie_isr() PCI: mobiveil: Fix infinite-loop in the INTx handling function PCI: mobiveil: Move PCIe PIO enablement out of inbound window routine PCI: mobiveil: Add upper 32-bit PCI base address setup in inbound window PCI: mobiveil: Add upper 32-bit CPU base address setup in outbound window PCI: mobiveil: Mask out hardcoded bits in inbound/outbound windows setup PCI: mobiveil: Clear the control fields before updating it PCI: mobiveil: Add configured inbound windows counter PCI: mobiveil: Fix the valid check for inbound and outbound windows PCI: mobiveil: Clean-up program_{ib/ob}_windows() PCI: mobiveil: Remove an unnecessary return value check PCI: mobiveil: Fix error return values PCI: mobiveil: Refactor the MEM/IO outbound window initialization PCI: mobiveil: Make some register updates more readable PCI: mobiveil: Reformat the code for readability dt-bindings: PCI: mobiveil: Change gpio_slave and apb_csr to optional ...
2019-07-16selftests/bpf: remove logic duplication in test_verifierAndrii Nakryiko1-20/+15
test_verifier tests can specify single- and multi-runs tests. Internally logic of handling them is duplicated. Get rid of it by making single run retval/data specification to be a first run spec. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Cc: Krzesimir Nowak <krzesimir@kinvolk.io> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15bpf: sync bpf.h to tools/Stanislav Fomichev1-2/+2
Update bpf_sock_addr comments to indicate support for 8-byte reads from user_ip6 and msg_src_ip6. Cc: Yonghong Song <yhs@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: add selftests for wide loadsStanislav Fomichev1-0/+37
Mirror existing wide store tests with wide loads. The only significant difference is expected error string. Cc: Yonghong Song <yhs@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: rename verifier/wide_store.c to verifier/wide_access.cStanislav Fomichev2-36/+36
Move the file and rename internal BPF_SOCK_ADDR define to BPF_SOCK_ADDR_STORE. This selftest will be extended in the next commit with the wide loads. Cc: Yonghong Song <yhs@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: put test_stub.o into $(OUTPUT)Ilya Leoshkevich1-2/+5
Add a rule to put test_stub.o in $(OUTPUT) and change the references to it accordingly. This prevents test_stub.o from being created in the source directory. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: make directory prerequisites order-onlyIlya Leoshkevich1-8/+8
When directories are used as prerequisites in Makefiles, they can cause a lot of unnecessary rebuilds, because a directory is considered changed whenever a file in this directory is added, removed or modified. If the only thing a target is interested in is the existence of the directory it depends on, which is the case for selftests/bpf, this directory should be specified as an order-only prerequisite: it would still be created in case it does not exist, but it would not trigger a rebuild of a target in case it's considered changed. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: fix attach_probe on s390Ilya Leoshkevich1-0/+2
attach_probe test fails, because it cannot install a kprobe on a non-existent sys_nanosleep symbol. Use the correct symbol name for the nanosleep syscall on 64-bit s390. Don't bother adding one for 31-bit mode, since tests are compiled only in 64-bit mode. Fixes: 1e8611bbdfc9 ("selftests/bpf: add kprobe/uprobe selftests") Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Acked-by: Vasily Gorbik <gor@linux.ibm.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: use typedef'ed arrays as map valuesAndrii Nakryiko3-4/+4
Convert few tests that couldn't use typedef'ed arrays due to kernel bug. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15selftests/bpf: add trickier size resolution testsAndrii Nakryiko1-0/+88
Add more BTF tests, validating that size resolution logic is correct in few trickier cases. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-07-15Revert "x86/ptrace: Prevent ptrace from clearing the FS/GS selector" and fix the testAndy Lutomirski1-18/+4
This reverts commit 48f5e52e916b55fb73754833efbacc7f8081a159. The ptrace ABI change was a prerequisite to the proposed design for FSGSBASE. Since FSGSBASE support has been reverted, and since I'm not convinced that the ABI was ever adequately tested, revert the ABI change as well. This also modifies the test case so that it tests the preexisting behavior. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/fca39c478ea7fb15bc76fe8a36bd180810a067f6.1563200250.git.luto@kernel.org
2019-07-15LSM: SafeSetID: verify transitive constrainednessJann Horn1-1/+3
Someone might write a ruleset like the following, expecting that it securely constrains UID 1 to UIDs 1, 2 and 3: 1:2 1:3 However, because no constraints are applied to UIDs 2 and 3, an attacker with UID 1 can simply first switch to UID 2, then switch to any UID from there. The secure way to write this ruleset would be: 1:2 1:3 2:2 3:3 , which uses "transition to self" as a way to inhibit the default-allow policy without allowing anything specific. This is somewhat unintuitive. To make sure that policy authors don't accidentally write insecure policies because of this, let the kernel verify that a new ruleset does not contain any entries that are constrained, but transitively unconstrained. Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Micah Morton <mortonm@chromium.org>
2019-07-15LSM: SafeSetID: rewrite userspace API to atomic updatesJann Horn1-11/+5
The current API of the SafeSetID LSM uses one write() per rule, and applies each written rule instantly. This has several downsides: - While a policy is being loaded, once a single parent-child pair has been loaded, the parent is restricted to that specific child, even if subsequent rules would allow transitions to other child UIDs. This means that during policy loading, set*uid() can randomly fail. - To replace the policy without rebooting, it is necessary to first flush all old rules. This creates a time window in which no constraints are placed on the use of CAP_SETUID. - If we want to perform sanity checks on the final policy, this requires that the policy isn't constructed in a piecemeal fashion without telling the kernel when it's done. Other kernel APIs - including things like the userns code and netfilter - avoid this problem by performing updates atomically. Luckily, SafeSetID hasn't landed in a stable (upstream) release yet, so maybe it's not too late to completely change the API. The new API for SafeSetID is: If you want to change the policy, open "safesetid/whitelist_policy" and write the entire policy, newline-delimited, in there. Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Micah Morton <mortonm@chromium.org>
2019-07-15docs: cgroup-v1: add it to the admin-guide bookMauro Carvalho Chehab1-1/+1
Those files belong to the admin guide, so add them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15docs: blockdev: add it to the admin-guideMauro Carvalho Chehab1-1/+1
The blockdev book basically contains user-faced documentation. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-15docs: blockdev: convert to ReSTMauro Carvalho Chehab1-1/+1
Rename the blockdev documentation files to ReST, add an index for them and adjust in order to produce a nice html output via the Sphinx build system. The drbd sub-directory contains some graphs and data flows. Add those too to the documentation. At its new index.rst, let's add a :orphan: while this is not linked to the main index.rst file, in order to avoid build warnings. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.