linux-dev/tools/objtool, branch linus/master

x86/extable: Annotate ex_handler_msr_mce() as a dead end

2022-05-27T10:34:45Z

Fix vmlinux.o: warning: objtool: fixup_exception+0x2d6: unreachable instruction Signed-off-by: Borislav Petkov Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220520192729.23969-1-bp@alien8.de

objtool: Mark __ubsan_handle_builtin_unreachable() as noreturn

2022-05-27T10:34:43Z

fs/ntfs3/ntfs3.prelink.o: warning: objtool: ni_read_frame() falls through to next function ni_readpage_cmpr.cold() That is in fact: 000000000000124a : 124a: 44 89 e0 mov %r12d,%eax 124d: 0f b6 55 98 movzbl -0x68(%rbp),%edx 1251: 48 c7 c7 00 00 00 00 mov $0x0,%rdi 1254: R_X86_64_32S .data+0x1380 1258: 48 89 c6 mov %rax,%rsi 125b: e8 00 00 00 00 call 1260 125c: R_X86_64_PLT32 __ubsan_handle_shift_out_of_bounds-0x4 1260: 48 8d 7d cc lea -0x34(%rbp),%rdi 1264: e8 00 00 00 00 call 1269 1265: R_X86_64_PLT32 __tsan_read4-0x4 1269: 8b 45 cc mov -0x34(%rbp),%eax 126c: e9 00 00 00 00 jmp 1271 126d: R_X86_64_PC32 .text+0x19109 1271: 48 8b 75 a0 mov -0x60(%rbp),%rsi 1275: 48 63 d0 movslq %eax,%rdx 1278: 48 c7 c7 00 00 00 00 mov $0x0,%rdi 127b: R_X86_64_32S .data+0x13a0 127f: 89 45 88 mov %eax,-0x78(%rbp) 1282: e8 00 00 00 00 call 1287 1283: R_X86_64_PLT32 __ubsan_handle_shift_out_of_bounds-0x4 1287: 8b 45 88 mov -0x78(%rbp),%eax 128a: e9 00 00 00 00 jmp 128f 128b: R_X86_64_PC32 .text+0x19098 128f: 48 c7 c7 00 00 00 00 mov $0x0,%rdi 1292: R_X86_64_32S .data+0x11f0 1296: e8 00 00 00 00 call 129b 1297: R_X86_64_PLT32 __ubsan_handle_builtin_unreachable-0x4 000000000000129b : Tell objtool that __ubsan_handle_builtin_unreachable() is a noreturn. Reported-by: kernel test robot Signed-off-by: Peter Zijlstra (Intel) Link: https://lkml.kernel.org/r/20220502091514.GB479834@worktop.programming.kicks-ass.net

Merge tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2022-05-26T19:09:50Z

Pull Kbuild updates from Masahiro Yamada: - Add HOSTPKG_CONFIG env variable to allow users to override pkg-config - Support W=e as a shorthand for KCFLAGS=-Werror - Fix CONFIG_IKHEADERS build to support toybox cpio - Add scripts/dummy-tools/pahole to ease distro packagers' life - Suppress false-positive warnings from checksyscalls.sh for W=2 build - Factor out the common code of arch/*/boot/install.sh into scripts/install.sh - Support 'kernel-install' tool in scripts/prune-kernel - Refactor module-versioning to link the symbol versions at the final link of vmlinux and modules - Remove CONFIG_MODULE_REL_CRCS because module-versioning now works in an arch-agnostic way - Refactor modpost, Makefiles * tag 'kbuild-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (56 commits) genksyms: adjust the output format to modpost kbuild: stop merging *.symversions kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS modpost: extract symbol versions from *.cmd files modpost: add sym_find_with_module() helper modpost: change the license of EXPORT_SYMBOL to bool type modpost: remove left-over cross_compile declaration kbuild: record symbol versions in *.cmd files kbuild: generate a list of objects in vmlinux modpost: move *.mod.c generation to write_mod_c_files() modpost: merge add_{intree_flag,retpoline,staging_flag} to add_header scripts/prune-kernel: Use kernel-install if available kbuild: factor out the common installation code into scripts/install.sh modpost: split new_symbol() to symbol allocation and hash table addition modpost: make sym_add_exported() always allocate a new symbol modpost: make multiple export error modpost: dump Module.symvers in the same order of modules.order modpost: traverse the namespace_list in order modpost: use doubly linked list for dump_lists modpost: traverse unresolved symbols in order ...

objtool: Fix objtool regression on x32 systems

2022-05-20T10:45:30Z

Commit c087c6e7b551 ("objtool: Fix type of reloc::addend") failed to appreciate cross building from ILP32 hosts, where 'int' == 'long' and the issue persists. As such, use s64/int64_t/Elf64_Sxword for this field and suffer the pain that is ISO C99 printf formats for it. Fixes: c087c6e7b551 ("objtool: Fix type of reloc::addend") Signed-off-by: Mikulas Patocka [peterz: reword changelog, s/long long/s64/] Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Cc: Link: https://lkml.kernel.org/r/alpine.LRH.2.02.2205161041260.11556@file01.intranet.prod.int.rdu2.redhat.com

objtool: Fix symbol creation

2022-05-20T10:42:06Z

Nathan reported objtool failing with the following messages: warning: objtool: no non-local symbols !? warning: objtool: gelf_update_symshndx: invalid section index The problem is due to commit 4abff6d48dbc ("objtool: Fix code relocs vs weak symbols") failing to consider the case where an object would have no non-local symbols. The problem that commit tries to address is adding a STB_LOCAL symbol to the symbol table in light of the ELF spec's requirement that: In each symbol table, all symbols with STB_LOCAL binding preced the weak and global symbols. As ``Sections'' above describes, a symbol table section's sh_info section header member holds the symbol table index for the first non-local symbol. The approach taken is to find this first non-local symbol, move that to the end and then re-use the freed spot to insert a new local symbol and increment sh_info. Except it never considered the case of object files without global symbols and got a whole bunch of details wrong -- so many in fact that it is a wonder it ever worked :/ Specifically: - It failed to re-hash the symbol on the new index, so a subsequent find_symbol_by_index() would not find it at the new location and a query for the old location would now return a non-deterministic choice between the old and new symbol. - It failed to appreciate that the GElf wrappers are not a valid disk format (it works because GElf is basically Elf64 and we only support x86_64 atm.) - It failed to fully appreciate how horrible the libelf API really is and got the gelf_update_symshndx() call pretty much completely wrong; with the direct consequence that if inserting a second STB_LOCAL symbol would require moving the same STB_GLOBAL symbol again it would completely come unstuck. Write a new elf_update_symbol() function that wraps all the magic required to update or create a new symbol at a given index. Specifically, gelf_update_sym*() require an @ndx argument that is relative to the @data argument; this means you have to manually iterate the section data descriptor list and update @ndx. Fixes: 4abff6d48dbc ("objtool: Fix code relocs vs weak symbols") Reported-by: Nathan Chancellor Signed-off-by: Peter Zijlstra (Intel) Signed-off-by: Borislav Petkov Acked-by: Josh Poimboeuf Tested-by: Nathan Chancellor Cc: Link: https://lkml.kernel.org/r/YoPCTEYjoPqE4ZxB@hirez.programming.kicks-ass.net

objtool: Remove libsubcmd.a when make clean

2022-05-12T14:28:35Z

The file libsubcmd.a still exists after make clean, remove it. Signed-off-by: Tiezhu Yang Signed-off-by: Josh Poimboeuf Link: https://lore.kernel.org/r/1652258270-6278-3-git-send-email-yangtiezhu@loongson.cn

objtool: Remove inat-tables.c when make clean

2022-05-12T14:28:05Z

When build objtool on x86, the generated file inat-tables.c is in arch/x86/lib instead of arch/x86, use the correct dir to remove it when make clean. $ cd tools/objtool $ make [...] GEN arch/x86/lib/inat-tables.c [...] Signed-off-by: Tiezhu Yang Signed-off-by: Josh Poimboeuf Link: https://lore.kernel.org/r/1652258270-6278-2-git-send-email-yangtiezhu@loongson.cn

objtool: Update documentation

2022-04-22T10:32:05Z

The objtool documentation is very stack validation centric. Broaden the documentation and describe all the features objtool supports. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/b6a84d301d9f73ec6725752654097f4e31fa1b69.1650300597.git.jpoimboe@redhat.com

objtool: Remove --lto and --vmlinux in favor of --link

2022-04-22T10:32:05Z

The '--lto' option is a confusing way of telling objtool to do stack validation despite it being a linked object. It's no longer needed now that an explicit '--stackval' option exists. The '--vmlinux' option is also redundant. Remove both options in favor of a straightforward '--link' option which identifies a linked object. Also, implicitly set '--link' with a warning if the user forgets to do so and we can tell that it's a linked object. This makes it easier for manual vmlinux runs. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/dcd3ceffd15a54822c6183e5766d21ad06082b45.1650300597.git.jpoimboe@redhat.com

objtool: Make noinstr hacks optional

2022-04-22T10:32:04Z

Objtool has some hacks in place to workaround toolchain limitations which otherwise would break no-instrumentation rules. Make the hacks explicit (and optional for other arches) by turning it into a cmdline option and kernel config option. Signed-off-by: Josh Poimboeuf Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Miroslav Benes Link: https://lkml.kernel.org/r/b326eeb9c33231b9dfbb925f194ed7ee40edcd7c.1650300597.git.jpoimboe@redhat.com