kernel/linux.git/tools, branch v5.15.38

objtool: Fix type of reloc::addend

2022-05-09T07:14:44+00:00

commit c087c6e7b551b7f208c0b852304f044954cf2bb3 upstream. Elf{32,64}_Rela::r_addend is of type: Elf{32,64}_Sword, that means that our reloc::addend needs to be long or face tuncation issues when we do elf_rebuild_reloc_section(): - 107: 48 b8 00 00 00 00 00 00 00 00 movabs $0x0,%rax 109: R_X86_64_64 level4_kernel_pgt+0x80000067 + 107: 48 b8 00 00 00 00 00 00 00 00 movabs $0x0,%rax 109: R_X86_64_64 level4_kernel_pgt-0x7fffff99 Fixes: 627fce14809b ("objtool: Add ORC unwind table generation") Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lkml.kernel.org/r/20220419203807.596871927@infradead.org Signed-off-by: Greg Kroah-Hartman

objtool: Fix code relocs vs weak symbols

2022-05-09T07:14:44+00:00

commit 4abff6d48dbcea8200c7ea35ba70c242d128ebf3 upstream. Occasionally objtool driven code patching (think .static_call_sites .retpoline_sites etc..) goes sideways and it tries to patch an instruction that doesn't match. Much head-scatching and cursing later the problem is as outlined below and affects every section that objtool generates for us, very much including the ORC data. The below uses .static_call_sites because it's convenient for demonstration purposes, but as mentioned the ORC sections, .retpoline_sites and __mount_loc are all similarly affected. Consider: foo-weak.c: extern void __SCT__foo(void); __attribute__((weak)) void foo(void) { return __SCT__foo(); } foo.c: extern void __SCT__foo(void); extern void my_foo(void); void foo(void) { my_foo(); return __SCT__foo(); } These generate the obvious code (gcc -O2 -fcf-protection=none -fno-asynchronous-unwind-tables -c foo*.c): foo-weak.o: 0000000000000000 : 0: e9 00 00 00 00 jmpq 5 1: R_X86_64_PLT32 __SCT__foo-0x4 foo.o: 0000000000000000 : 0: 48 83 ec 08 sub $0x8,%rsp 4: e8 00 00 00 00 callq 9 5: R_X86_64_PLT32 my_foo-0x4 9: 48 83 c4 08 add $0x8,%rsp d: e9 00 00 00 00 jmpq 12 e: R_X86_64_PLT32 __SCT__foo-0x4 Now, when we link these two files together, you get something like (ld -r -o foos.o foo-weak.o foo.o): foos.o: 0000000000000000 : 0: e9 00 00 00 00 jmpq 5 1: R_X86_64_PLT32 __SCT__foo-0x4 5: 66 2e 0f 1f 84 00 00 00 00 00 nopw %cs:0x0(%rax,%rax,1) f: 90 nop 0000000000000010 : 10: 48 83 ec 08 sub $0x8,%rsp 14: e8 00 00 00 00 callq 19 15: R_X86_64_PLT32 my_foo-0x4 19: 48 83 c4 08 add $0x8,%rsp 1d: e9 00 00 00 00 jmpq 22 1e: R_X86_64_PLT32 __SCT__foo-0x4 Noting that ld preserves the weak function text, but strips the symbol off of it (hence objdump doing that funny negative offset thing). This does lead to 'interesting' unused code issues with objtool when ran on linked objects, but that seems to be working (fingers crossed). So far so good.. Now lets consider the objtool static_call output section (readelf output, old binutils): foo-weak.o: Relocation section '.rela.static_call_sites' at offset 0x2c8 contains 1 entry: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000000200000002 R_X86_64_PC32 0000000000000000 .text + 0 0000000000000004 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 foo.o: Relocation section '.rela.static_call_sites' at offset 0x310 contains 2 entries: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000000200000002 R_X86_64_PC32 0000000000000000 .text + d 0000000000000004 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 foos.o: Relocation section '.rela.static_call_sites' at offset 0x430 contains 4 entries: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000000100000002 R_X86_64_PC32 0000000000000000 .text + 0 0000000000000004 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 0000000000000008 0000000100000002 R_X86_64_PC32 0000000000000000 .text + 1d 000000000000000c 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 So we have two patch sites, one in the dead code of the weak foo and one in the real foo. All is well. *HOWEVER*, when the toolchain strips unused section symbols it generates things like this (using new enough binutils): foo-weak.o: Relocation section '.rela.static_call_sites' at offset 0x2c8 contains 1 entry: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000000200000002 R_X86_64_PC32 0000000000000000 foo + 0 0000000000000004 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 foo.o: Relocation section '.rela.static_call_sites' at offset 0x310 contains 2 entries: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000000200000002 R_X86_64_PC32 0000000000000000 foo + d 0000000000000004 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 foos.o: Relocation section '.rela.static_call_sites' at offset 0x430 contains 4 entries: Offset Info Type Symbol's Value Symbol's Name + Addend 0000000000000000 0000000100000002 R_X86_64_PC32 0000000000000000 foo + 0 0000000000000004 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 0000000000000008 0000000100000002 R_X86_64_PC32 0000000000000000 foo + d 000000000000000c 0000000d00000002 R_X86_64_PC32 0000000000000000 __SCT__foo + 1 And now we can see how that foos.o .static_call_sites goes side-ways, we now have _two_ patch sites in foo. One for the weak symbol at foo+0 (which is no longer a static_call site!) and one at foo+d which is in fact the right location. This seems to happen when objtool cannot find a section symbol, in which case it falls back to any other symbol to key off of, however in this case that goes terribly wrong! As such, teach objtool to create a section symbol when there isn't one. Fixes: 44f6a7c0755d ("objtool: Fix seg fault with Clang non-section symbols") Signed-off-by: Peter Zijlstra (Intel) Acked-by: Josh Poimboeuf Link: https://lkml.kernel.org/r/20220419203807.655552918@infradead.org Signed-off-by: Greg Kroah-Hartman

perf symbol: Remove archsymbolsfixup_end()

2022-05-09T07:14:44+00:00

commit a5d20d42a2f2dc2b2f9e9361912062732414090d upstream. Now the generic code can handle kallsyms fixup properly so no need to keep the arch-functions anymore. Fixes: 3cf6a32f3f2a4594 ("perf symbols: Fix symbol size calculation condition") Signed-off-by: Namhyung Kim Acked-by: Ian Rogers Cc: Heiko Carstens Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Mathieu Poirier Cc: Michael Ellerman Cc: Michael Petlan Cc: Peter Zijlstra Cc: Song Liu Cc: Will Deacon Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20220416004048.1514900-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf symbol: Update symbols__fixup_end()

2022-05-09T07:14:42+00:00

commit 8799ebce84d672aae1dc3170510f6a3e66f96b11 upstream. Now arch-specific functions all do the same thing. When it fixes the symbol address it needs to check the boundary between the kernel image and modules. For the last symbol in the previous region, it cannot know the exact size as it's discarded already. Thus it just uses a small page size (4096) and rounds it up like the last symbol. Fixes: 3cf6a32f3f2a4594 ("perf symbols: Fix symbol size calculation condition") Signed-off-by: Namhyung Kim Acked-by: Ian Rogers Cc: Heiko Carstens Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Mathieu Poirier Cc: Michael Ellerman Cc: Michael Petlan Cc: Peter Zijlstra Cc: Song Liu Cc: Will Deacon Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20220416004048.1514900-3-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

perf symbol: Pass is_kallsyms to symbols__fixup_end()

2022-05-09T07:14:42+00:00

commit 838425f2defe5262906b698752d28fd2fca1aac2 upstream. The symbol fixup is necessary for symbols in kallsyms since they don't have size info. So we use the next symbol's address to calculate the size. Now it's also used for user binaries because sometimes they miss size for hand-written asm functions. There's a arch-specific function to handle kallsyms differently but currently it cannot distinguish kallsyms from others. Pass this information explicitly to handle it properly. Note that those arch functions will be moved to the generic function so I didn't added it to the arch-functions. Fixes: 3cf6a32f3f2a4594 ("perf symbols: Fix symbol size calculation condition") Signed-off-by: Namhyung Kim Acked-by: Ian Rogers Cc: Heiko Carstens Cc: Ingo Molnar Cc: Jiri Olsa Cc: John Garry Cc: Leo Yan Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Mathieu Poirier Cc: Michael Ellerman Cc: Michael Petlan Cc: Peter Zijlstra Cc: Song Liu Cc: Will Deacon Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20220416004048.1514900-2-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

selftest/vm: verify remap destination address in mremap_test

2022-05-09T07:14:40+00:00

[ Upstream commit 18d609daa546c919fd36b62a7b510c18de4b4af8 ] Because mremap does not have a MAP_FIXED_NOREPLACE flag, it can destroy existing mappings. This causes a segfault when regions such as text are remapped and the permissions are changed. Verify the requested mremap destination address does not overlap any existing mappings by using mmap's MAP_FIXED_NOREPLACE flag. Keep incrementing the destination address until a valid mapping is found or fail the current test once the max address is reached. Link: https://lkml.kernel.org/r/20220420215721.4868-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar Reviewed-by: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

selftest/vm: verify mmap addr in mremap_test

2022-05-09T07:14:40+00:00

[ Upstream commit 9c85a9bae267f6b5e5e374d0d023bbbe9db096d3 ] Avoid calling mmap with requested addresses that are less than the system's mmap_min_addr. When run as root, mmap returns EACCES when trying to map addresses < mmap_min_addr. This is not one of the error codes for the condition to retry the mmap in the test. Rather than arbitrarily retrying on EACCES, don't attempt an mmap until addr > vm.mmap_min_addr. Add a munmap call after an alignment check as the mappings are retained after the retry and can reach the vm.max_map_count sysctl. Link: https://lkml.kernel.org/r/20220420215721.4868-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar Reviewed-by: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

perf arm-spe: Fix addresses of synthesized SPE events

2022-05-09T07:14:39+00:00

[ Upstream commit 4e13f6706d5aee1a6b835a44f6cf4971a921dcb8 ] This patch corrects a bug whereby synthesized events from SPE samples are missing virtual addresses. Fixes: 54f7815efef7fad9 ("perf arm-spe: Fill address info for samples") Reviewed-by: Leo Yan Signed-off-by: Timothy Hayes Cc: Alexander Shishkin Cc: bpf@vger.kernel.org Cc: Jiri Olsa Cc: John Fastabend Cc: John Garry Cc: KP Singh Cc: Leo Yan Cc: linux-arm-kernel@lists.infradead.org Cc: Mark Rutland Cc: Martin KaFai Lau Cc: Mathieu Poirier Cc: Namhyung Kim Cc: netdev@vger.kernel.org Cc: Song Liu Cc: Will Deacon Cc: Yonghong Song Link: https://lore.kernel.org/r/20220421165205.117662-2-timothy.hayes@arm.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

selftests/bpf: Add test for reg2btf_ids out of bounds access

2022-05-01T15:22:34+00:00

commit 13c6a37d409db9abc9c0bfc6d0a2f07bf0fff60e upstream. This test tries to pass a PTR_TO_BTF_ID_OR_NULL to the release function, which would trigger a out of bounds access without the fix in commit 45ce4b4f9009 ("bpf: Fix crash due to out of bounds access into reg2btf_ids.") but after the fix, it should only index using base_type(reg->type), which should be less than __BPF_REG_TYPE_MAX, and also not permit any type flags to be set for the reg->type. Signed-off-by: Kumar Kartikeya Dwivedi Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/20220220023138.2224652-1-memxor@gmail.com Signed-off-by: Greg Kroah-Hartman

bpf/selftests: Test PTR_TO_RDONLY_MEM

2022-05-01T15:22:26+00:00

commit 9497c458c10b049438ef6e6ddda898edbc3ec6a8 upstream. This test verifies that a ksym of non-struct can not be directly updated. Signed-off-by: Hao Luo Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20211217003152.48334-10-haoluo@google.com Cc: stable@vger.kernel.org # 5.15.x Signed-off-by: Greg Kroah-Hartman

kernel/linux.git/tools, branch v5.15.38

objtool: Fix type of reloc::addend

objtool: Fix code relocs vs weak symbols

perf symbol: Remove arch__symbols__fixup_end()

perf symbol: Update symbols__fixup_end()

perf symbol: Pass is_kallsyms to symbols__fixup_end()

selftest/vm: verify remap destination address in mremap_test

selftest/vm: verify mmap addr in mremap_test

perf arm-spe: Fix addresses of synthesized SPE events

selftests/bpf: Add test for reg2btf_ids out of bounds access

bpf/selftests: Test PTR_TO_RDONLY_MEM

perf symbol: Remove archsymbolsfixup_end()