From: Greg Kroah-Hartman Date: Sat, 13 Feb 2021 13:15:59 +0000 (+0100) Subject: 5.10-stable patches X-Git-Tag: v5.4.99~48 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=241b3eb53391ce30739664d5ffabe64eedf1bd9d;p=thirdparty%2Fkernel%2Fstable-queue.git 5.10-stable patches added patches: objtool-fix-seg-fault-with-clang-non-section-symbols.patch --- diff --git a/queue-5.10/objtool-fix-seg-fault-with-clang-non-section-symbols.patch b/queue-5.10/objtool-fix-seg-fault-with-clang-non-section-symbols.patch new file mode 100644 index 00000000000..4248a64d91a --- /dev/null +++ b/queue-5.10/objtool-fix-seg-fault-with-clang-non-section-symbols.patch @@ -0,0 +1,144 @@ +From 44f6a7c0755d8dd453c70557e11687bb080a6f21 Mon Sep 17 00:00:00 2001 +From: Josh Poimboeuf +Date: Mon, 14 Dec 2020 16:04:20 -0600 +Subject: objtool: Fix seg fault with Clang non-section symbols + +From: Josh Poimboeuf + +commit 44f6a7c0755d8dd453c70557e11687bb080a6f21 upstream. + +The Clang assembler likes to strip section symbols, which means objtool +can't reference some text code by its section. This confuses objtool +greatly, causing it to seg fault. + +The fix is similar to what was done before, for ORC reloc generation: + + e81e07244325 ("objtool: Support Clang non-section symbols in ORC generation") + +Factor out that code into a common helper and use it for static call +reloc generation as well. + +Reported-by: Arnd Bergmann +Signed-off-by: Josh Poimboeuf +Signed-off-by: Peter Zijlstra (Intel) +Reviewed-by: Nick Desaulniers +Reviewed-by: Miroslav Benes +Link: https://github.com/ClangBuiltLinux/linux/issues/1207 +Link: https://lkml.kernel.org/r/ba6b6c0f0dd5acbba66e403955a967d9fdd1726a.1607983452.git.jpoimboe@redhat.com +Signed-off-by: Greg Kroah-Hartman +--- + tools/objtool/check.c | 11 +++++++++-- + tools/objtool/elf.c | 26 ++++++++++++++++++++++++++ + tools/objtool/elf.h | 2 ++ + tools/objtool/orc_gen.c | 29 +++++------------------------ + 4 files changed, 42 insertions(+), 26 deletions(-) + +--- a/tools/objtool/check.c ++++ b/tools/objtool/check.c +@@ -467,13 +467,20 @@ static int create_static_call_sections(s + + /* populate reloc for 'addr' */ + reloc = malloc(sizeof(*reloc)); ++ + if (!reloc) { + perror("malloc"); + return -1; + } + memset(reloc, 0, sizeof(*reloc)); +- reloc->sym = insn->sec->sym; +- reloc->addend = insn->offset; ++ ++ insn_to_reloc_sym_addend(insn->sec, insn->offset, reloc); ++ if (!reloc->sym) { ++ WARN_FUNC("static call tramp: missing containing symbol", ++ insn->sec, insn->offset); ++ return -1; ++ } ++ + reloc->type = R_X86_64_PC32; + reloc->offset = idx * sizeof(struct static_call_site); + reloc->sec = reloc_sec; +--- a/tools/objtool/elf.c ++++ b/tools/objtool/elf.c +@@ -262,6 +262,32 @@ struct reloc *find_reloc_by_dest(const s + return find_reloc_by_dest_range(elf, sec, offset, 1); + } + ++void insn_to_reloc_sym_addend(struct section *sec, unsigned long offset, ++ struct reloc *reloc) ++{ ++ if (sec->sym) { ++ reloc->sym = sec->sym; ++ reloc->addend = offset; ++ return; ++ } ++ ++ /* ++ * The Clang assembler strips section symbols, so we have to reference ++ * the function symbol instead: ++ */ ++ reloc->sym = find_symbol_containing(sec, offset); ++ if (!reloc->sym) { ++ /* ++ * Hack alert. This happens when we need to reference the NOP ++ * pad insn immediately after the function. ++ */ ++ reloc->sym = find_symbol_containing(sec, offset - 1); ++ } ++ ++ if (reloc->sym) ++ reloc->addend = offset - reloc->sym->offset; ++} ++ + static int read_sections(struct elf *elf) + { + Elf_Scn *s = NULL; +--- a/tools/objtool/elf.h ++++ b/tools/objtool/elf.h +@@ -140,6 +140,8 @@ struct reloc *find_reloc_by_dest(const s + struct reloc *find_reloc_by_dest_range(const struct elf *elf, struct section *sec, + unsigned long offset, unsigned int len); + struct symbol *find_func_containing(struct section *sec, unsigned long offset); ++void insn_to_reloc_sym_addend(struct section *sec, unsigned long offset, ++ struct reloc *reloc); + int elf_rebuild_reloc_section(struct elf *elf, struct section *sec); + + #define for_each_sec(file, sec) \ +--- a/tools/objtool/orc_gen.c ++++ b/tools/objtool/orc_gen.c +@@ -105,30 +105,11 @@ static int create_orc_entry(struct elf * + } + memset(reloc, 0, sizeof(*reloc)); + +- if (insn_sec->sym) { +- reloc->sym = insn_sec->sym; +- reloc->addend = insn_off; +- } else { +- /* +- * The Clang assembler doesn't produce section symbols, so we +- * have to reference the function symbol instead: +- */ +- reloc->sym = find_symbol_containing(insn_sec, insn_off); +- if (!reloc->sym) { +- /* +- * Hack alert. This happens when we need to reference +- * the NOP pad insn immediately after the function. +- */ +- reloc->sym = find_symbol_containing(insn_sec, +- insn_off - 1); +- } +- if (!reloc->sym) { +- WARN("missing symbol for insn at offset 0x%lx\n", +- insn_off); +- return -1; +- } +- +- reloc->addend = insn_off - reloc->sym->offset; ++ insn_to_reloc_sym_addend(insn_sec, insn_off, reloc); ++ if (!reloc->sym) { ++ WARN("missing symbol for insn at offset 0x%lx", ++ insn_off); ++ return -1; + } + + reloc->type = R_X86_64_PC32; diff --git a/queue-5.10/series b/queue-5.10/series new file mode 100644 index 00000000000..c6022b04f40 --- /dev/null +++ b/queue-5.10/series @@ -0,0 +1 @@ +objtool-fix-seg-fault-with-clang-non-section-symbols.patch diff --git a/queue-5.4/series b/queue-5.4/series new file mode 100644 index 00000000000..e69de29bb2d