diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-23 20:56:13 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2021-02-23 20:56:13 +0300 |
commit | a56ff24efbba18f4361415597f145f4b5773be3e (patch) | |
tree | 228932f20338940071105e14ba044a2b28a6442e | |
parent | 79db4d2293eba2ce6265a341bedf6caecad5eeb3 (diff) | |
parent | aafeb14e9da29e323b0605f8f1bae0d45d5f3acf (diff) | |
download | linux-a56ff24efbba18f4361415597f145f4b5773be3e.tar.xz |
Merge tag 'objtool-core-2021-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull objtool updates from Thomas Gleixner:
- Make objtool work for big-endian cross compiles
- Make stack tracking via stack pointer memory operations match
push/pop semantics to prepare for architectures w/o PUSH/POP
instructions.
- Add support for analyzing alternatives
- Improve retpoline detection and handling
- Improve assembly code coverage on x86
- Provide support for inlined stack switching
* tag 'objtool-core-2021-02-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
objtool: Support stack-swizzle
objtool,x86: Additionally decode: mov %rsp, (%reg)
x86/unwind/orc: Change REG_SP_INDIRECT
x86/power: Support objtool validation in hibernate_asm_64.S
x86/power: Move restore_registers() to top of the file
x86/power: Annotate indirect branches as safe
x86/acpi: Support objtool validation in wakeup_64.S
x86/acpi: Annotate indirect branch as safe
x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S
x86/xen/pvh: Annotate indirect branch as safe
x86/xen: Support objtool vmlinux.o validation in xen-head.S
x86/xen: Support objtool validation in xen-asm.S
objtool: Add xen_start_kernel() to noreturn list
objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC
objtool: Add asm version of STACK_FRAME_NON_STANDARD
objtool: Assume only ELF functions do sibling calls
x86/ftrace: Add UNWIND_HINT_FUNC annotation for ftrace_stub
objtool: Support retpoline jump detection for vmlinux.o
objtool: Fix ".cold" section suffix check for newer versions of GCC
objtool: Fix retpoline detection in asm code
...
49 files changed, 962 insertions, 597 deletions
diff --git a/arch/x86/include/asm/insn.h b/arch/x86/include/asm/insn.h index a8c3d284fa46..95a448fbb44c 100644 --- a/arch/x86/include/asm/insn.h +++ b/arch/x86/include/asm/insn.h @@ -7,9 +7,12 @@ * Copyright (C) IBM Corporation, 2009 */ +#include <asm/byteorder.h> /* insn_attr_t is defined in inat.h */ #include <asm/inat.h> +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN) + struct insn_field { union { insn_value_t value; @@ -20,6 +23,48 @@ struct insn_field { unsigned char nbytes; }; +static inline void insn_field_set(struct insn_field *p, insn_value_t v, + unsigned char n) +{ + p->value = v; + p->nbytes = n; +} + +static inline void insn_set_byte(struct insn_field *p, unsigned char n, + insn_byte_t v) +{ + p->bytes[n] = v; +} + +#else + +struct insn_field { + insn_value_t value; + union { + insn_value_t little; + insn_byte_t bytes[4]; + }; + /* !0 if we've run insn_get_xxx() for this field */ + unsigned char got; + unsigned char nbytes; +}; + +static inline void insn_field_set(struct insn_field *p, insn_value_t v, + unsigned char n) +{ + p->value = v; + p->little = __cpu_to_le32(v); + p->nbytes = n; +} + +static inline void insn_set_byte(struct insn_field *p, unsigned char n, + insn_byte_t v) +{ + p->bytes[n] = v; + p->value = __le32_to_cpu(p->little); +} +#endif + struct insn { struct insn_field prefixes; /* * Prefixes diff --git a/arch/x86/include/asm/orc_types.h b/arch/x86/include/asm/orc_types.h index fdbffec4cfde..5a2baf28a1dc 100644 --- a/arch/x86/include/asm/orc_types.h +++ b/arch/x86/include/asm/orc_types.h @@ -40,6 +40,8 @@ #define ORC_REG_MAX 15 #ifndef __ASSEMBLY__ +#include <asm/byteorder.h> + /* * This struct is more or less a vastly simplified version of the DWARF Call * Frame Information standard. It contains only the necessary parts of DWARF @@ -51,10 +53,18 @@ struct orc_entry { s16 sp_offset; s16 bp_offset; +#if defined(__LITTLE_ENDIAN_BITFIELD) unsigned sp_reg:4; unsigned bp_reg:4; unsigned type:2; unsigned end:1; +#elif defined(__BIG_ENDIAN_BITFIELD) + unsigned bp_reg:4; + unsigned sp_reg:4; + unsigned unused:5; + unsigned end:1; + unsigned type:2; +#endif } __packed; #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/include/asm/unwind_hints.h b/arch/x86/include/asm/unwind_hints.h index 664d4610d700..8e574c0afef8 100644 --- a/arch/x86/include/asm/unwind_hints.h +++ b/arch/x86/include/asm/unwind_hints.h @@ -48,17 +48,8 @@ UNWIND_HINT_REGS base=\base offset=\offset partial=1 .endm -.macro UNWIND_HINT_FUNC sp_offset=8 - UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=\sp_offset type=UNWIND_HINT_TYPE_CALL -.endm - -/* - * RET_OFFSET: Used on instructions that terminate a function; mostly RETURN - * and sibling calls. On these, sp_offset denotes the expected offset from - * initial_func_cfi. - */ -.macro UNWIND_HINT_RET_OFFSET sp_offset=8 - UNWIND_HINT sp_reg=ORC_REG_SP type=UNWIND_HINT_TYPE_RET_OFFSET sp_offset=\sp_offset +.macro UNWIND_HINT_FUNC + UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=8 type=UNWIND_HINT_TYPE_FUNC .endm #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/kernel/acpi/Makefile b/arch/x86/kernel/acpi/Makefile index f1bb57b0e41e..cf340d85946a 100644 --- a/arch/x86/kernel/acpi/Makefile +++ b/arch/x86/kernel/acpi/Makefile @@ -1,5 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 -OBJECT_FILES_NON_STANDARD_wakeup_$(BITS).o := y obj-$(CONFIG_ACPI) += boot.o obj-$(CONFIG_ACPI_SLEEP) += sleep.o wakeup_$(BITS).o diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S index 5d3a0b8fd379..56b6865afb2a 100644 --- a/arch/x86/kernel/acpi/wakeup_64.S +++ b/arch/x86/kernel/acpi/wakeup_64.S @@ -1,12 +1,14 @@ /* SPDX-License-Identifier: GPL-2.0-only */ .text #include <linux/linkage.h> +#include <linux/objtool.h> #include <asm/segment.h> #include <asm/pgtable_types.h> #include <asm/page_types.h> #include <asm/msr.h> #include <asm/asm-offsets.h> #include <asm/frame.h> +#include <asm/nospec-branch.h> # Copyright 2003 Pavel Machek <pavel@suse.cz @@ -39,6 +41,7 @@ SYM_FUNC_START(wakeup_long64) movq saved_rbp, %rbp movq saved_rip, %rax + ANNOTATE_RETPOLINE_SAFE jmp *%rax SYM_FUNC_END(wakeup_long64) @@ -126,6 +129,7 @@ SYM_FUNC_START(do_suspend_lowlevel) FRAME_END jmp restore_processor_state SYM_FUNC_END(do_suspend_lowlevel) +STACK_FRAME_NON_STANDARD do_suspend_lowlevel .data saved_rbp: .quad 0 diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 0d54099c2a3a..7c273846c687 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -184,6 +184,7 @@ SYM_INNER_LABEL(ftrace_graph_call, SYM_L_GLOBAL) * It is also used to copy the retq for trampolines. */ SYM_INNER_LABEL_ALIGN(ftrace_stub, SYM_L_WEAK) + UNWIND_HINT_FUNC retq SYM_FUNC_END(ftrace_epilogue) @@ -276,7 +277,7 @@ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) restore_mcount_regs 8 /* Restore flags */ popfq - UNWIND_HINT_RET_OFFSET + UNWIND_HINT_FUNC jmp ftrace_epilogue SYM_FUNC_END(ftrace_regs_caller) @@ -333,8 +334,7 @@ SYM_FUNC_START(ftrace_graph_caller) retq SYM_FUNC_END(ftrace_graph_caller) -SYM_CODE_START(return_to_handler) - UNWIND_HINT_EMPTY +SYM_FUNC_START(return_to_handler) subq $24, %rsp /* Save the return values */ @@ -349,5 +349,5 @@ SYM_CODE_START(return_to_handler) movq (%rsp), %rax addq $24, %rsp JMP_NOSPEC rdi -SYM_CODE_END(return_to_handler) +SYM_FUNC_END(return_to_handler) #endif diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c index 73f800100066..2a1d47f47eee 100644 --- a/arch/x86/kernel/unwind_orc.c +++ b/arch/x86/kernel/unwind_orc.c @@ -471,7 +471,7 @@ bool unwind_next_frame(struct unwind_state *state) break; case ORC_REG_SP_INDIRECT: - sp = state->sp + orc->sp_offset; + sp = state->sp; indirect = true; break; @@ -521,6 +521,9 @@ bool unwind_next_frame(struct unwind_state *state) if (indirect) { if (!deref_stack_reg(state, sp, &sp)) goto err; + + if (orc->sp_reg == ORC_REG_SP_INDIRECT) + sp += orc->sp_offset; } /* Find IP, SP and possibly regs: */ diff --git a/arch/x86/lib/insn.c b/arch/x86/lib/insn.c index 404279563891..435630a6ec97 100644 --- a/arch/x86/lib/insn.c +++ b/arch/x86/lib/insn.c @@ -5,6 +5,7 @@ * Copyright (C) IBM Corporation, 2002, 2004, 2009 */ +#include <linux/kernel.h> #ifdef __KERNEL__ #include <linux/string.h> #else @@ -15,15 +16,28 @@ #include <asm/emulate_prefix.h> +#define leXX_to_cpu(t, r) \ +({ \ + __typeof__(t) v; \ + switch (sizeof(t)) { \ + case 4: v = le32_to_cpu(r); break; \ + case 2: v = le16_to_cpu(r); break; \ + case 1: v = r; break; \ + default: \ + BUILD_BUG(); break; \ + } \ + v; \ +}) + /* Verify next sizeof(t) bytes can be on the same instruction */ #define validate_next(t, insn, n) \ ((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr) #define __get_next(t, insn) \ - ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; }) + ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); leXX_to_cpu(t, r); }) #define __peek_nbyte_next(t, insn, n) \ - ({ t r = *(t*)((insn)->next_byte + n); r; }) + ({ t r = *(t*)((insn)->next_byte + n); leXX_to_cpu(t, r); }) #define get_next(t, insn) \ ({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); }) @@ -147,9 +161,9 @@ found: b = insn->prefixes.bytes[3]; for (i = 0; i < nb; i++) if (prefixes->bytes[i] == lb) - prefixes->bytes[i] = b; + insn_set_byte(prefixes, i, b); } - insn->prefixes.bytes[3] = lb; + insn_set_byte(&insn->prefixes, 3, lb); } /* Decode REX prefix */ @@ -157,8 +171,7 @@ found: b = peek_next(insn_byte_t, insn); attr = inat_get_opcode_attribute(b); if (inat_is_rex_prefix(attr)) { - insn->rex_prefix.value = b; - insn->rex_prefix.nbytes = 1; + insn_field_set(&insn->rex_prefix, b, 1); insn->next_byte++; if (X86_REX_W(b)) /* REX.W overrides opnd_size */ @@ -181,13 +194,13 @@ found: if (X86_MODRM_MOD(b2) != 3) goto vex_end; } - insn->vex_prefix.bytes[0] = b; - insn->vex_prefix.bytes[1] = b2; + insn_set_byte(&insn->vex_prefix, 0, b); + insn_set_byte(&insn->vex_prefix, 1, b2); if (inat_is_evex_prefix(attr)) { b2 = peek_nbyte_next(insn_byte_t, insn, 2); - insn->vex_prefix.bytes[2] = b2; + insn_set_byte(&insn->vex_prefix, 2, b2); b2 = peek_nbyte_next(insn_byte_t, insn, 3); - insn->vex_prefix.bytes[3] = b2; + insn_set_byte(&insn->vex_prefix, 3, b2); insn->vex_prefix.nbytes = 4; insn->next_byte += 4; if (insn->x86_64 && X86_VEX_W(b2)) @@ -195,7 +208,7 @@ found: insn->opnd_bytes = 8; } else if (inat_is_vex3_prefix(attr)) { b2 = peek_nbyte_next(insn_byte_t, insn, 2); - insn->vex_prefix.bytes[2] = b2; + insn_set_byte(&insn->vex_prefix, 2, b2); insn->vex_prefix.nbytes = 3; insn->next_byte += 3; if (insn->x86_64 && X86_VEX_W(b2)) @@ -207,7 +220,7 @@ found: * Makes it easier to decode vex.W, vex.vvvv, * vex.L and vex.pp. Masking with 0x7f sets vex.W == 0. */ - insn->vex_prefix.bytes[2] = b2 & 0x7f; + insn_set_byte(&insn->vex_prefix, 2, b2 & 0x7f); insn->vex_prefix.nbytes = 2; insn->next_byte += 2; } @@ -243,7 +256,7 @@ void insn_get_opcode(struct insn *insn) /* Get first opcode */ op = get_next(insn_byte_t, insn); - opcode->bytes[0] = op; + insn_set_byte(opcode, 0, op); opcode->nbytes = 1; /* Check if there is VEX prefix or not */ @@ -295,8 +308,7 @@ void insn_get_modrm(struct insn *insn) if (inat_has_modrm(insn->attr)) { mod = get_next(insn_byte_t, insn); - modrm->value = mod; - modrm->nbytes = 1; + insn_field_set(modrm, mod, 1); if (inat_is_group(insn->attr)) { pfx_id = insn_last_prefix_id(insn); insn->attr = inat_get_group_attribute(mod, pfx_id, @@ -334,7 +346,7 @@ int insn_rip_relative(struct insn *insn) * For rip-relative instructions, the mod field (top 2 bits) * is zero and the r/m field (bottom 3 bits) is 0x5. */ - return (modrm->nbytes && (modrm->value & 0xc7) == 0x5); + return (modrm->nbytes && (modrm->bytes[0] & 0xc7) == 0x5); } /** @@ -353,11 +365,11 @@ void insn_get_sib(struct insn *insn) if (!insn->modrm.got) insn_get_modrm(insn); if (insn->modrm.nbytes) { - modrm = (insn_byte_t)insn->modrm.value; + modrm = insn->modrm.bytes[0]; if (insn->addr_bytes != 2 && X86_MODRM_MOD(modrm) != 3 && X86_MODRM_RM(modrm) == 4) { - insn->sib.value = get_next(insn_byte_t, insn); - insn->sib.nbytes = 1; + insn_field_set(&insn->sib, + get_next(insn_byte_t, insn), 1); } } insn->sib.got = 1; @@ -407,19 +419,18 @@ void insn_get_displacement(struct insn *insn) if (mod == 3) goto out; if (mod == 1) { - insn->displacement.value = get_next(signed char, insn); - insn->displacement.nbytes = 1; + insn_field_set(&insn->displacement, + get_next(signed char, insn), 1); } else if (insn->addr_bytes == 2) { if ((mod == 0 && rm == 6) || mod == 2) { - insn->displacement.value = - get_next(short, insn); - insn->displacement.nbytes = 2; + insn_field_set(&insn->displacement, + get_next(short, insn), 2); } } else { if ((mod == 0 && rm == 5) || mod == 2 || (mod == 0 && base == 5)) { - insn->displacement.value = get_next(int, insn); - insn->displacement.nbytes = 4; + insn_field_set(&insn->displacement, + get_next(int, insn), 4); } } } @@ -435,18 +446,14 @@ static int __get_moffset(struct insn *insn) { switch (insn->addr_bytes) { case 2: - insn->moffset1.value = get_next(short, insn); - insn->moffset1.nbytes = 2; + insn_field_set(&insn->moffset1, get_next(short, insn), 2); break; case 4: - insn->moffset1.value = get_next(int, insn); - insn->moffset1.nbytes = 4; + insn_field_set(&insn->moffset1, get_next(int, insn), 4); break; case 8: - insn->moffset1.value = get_next(int, insn); - insn->moffset1.nbytes = 4; - insn->moffset2.value = get_next(int, insn); - insn->moffset2.nbytes = 4; + insn_field_set(&insn->moffset1, get_next(int, insn), 4); + insn_field_set(&insn->moffset2, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -464,13 +471,11 @@ static int __get_immv32(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate.value = get_next(short, insn); - insn->immediate.nbytes = 2; + insn_field_set(&insn->immediate, get_next(short, insn), 2); break; case 4: case 8: - insn->immediate.value = get_next(int, insn); - insn->immediate.nbytes = 4; + insn_field_set(&insn->immediate, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -487,18 +492,15 @@ static int __get_immv(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate1.value = get_next(short, insn); - insn->immediate1.nbytes = 2; + insn_field_set(&insn->immediate1, get_next(short, insn), 2); break; case 4: - insn->immediate1.value = get_next(int, insn); + insn_field_set(&insn->immediate1, get_next(int, insn), 4); insn->immediate1.nbytes = 4; break; case 8: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; - insn->immediate2.value = get_next(int, insn); - insn->immediate2.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); + insn_field_set(&insn->immediate2, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -515,12 +517,10 @@ static int __get_immptr(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate1.value = get_next(short, insn); - insn->immediate1.nbytes = 2; + insn_field_set(&insn->immediate1, get_next(short, insn), 2); break; case 4: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); break; case 8: /* ptr16:64 is not exist (no segment) */ @@ -528,8 +528,7 @@ static int __get_immptr(struct insn *insn) default: /* opnd_bytes must be modified manually */ goto err_out; } - insn->immediate2.value = get_next(unsigned short, insn); - insn->immediate2.nbytes = 2; + insn_field_set(&insn->immediate2, get_next(unsigned short, insn), 2); insn->immediate1.got = insn->immediate2.got = 1; return 1; @@ -565,22 +564,17 @@ void insn_get_immediate(struct insn *insn) switch (inat_immediate_size(insn->attr)) { case INAT_IMM_BYTE: - insn->immediate.value = get_next(signed char, insn); - insn->immediate.nbytes = 1; + insn_field_set(&insn->immediate, get_next(signed char, insn), 1); break; case INAT_IMM_WORD: - insn->immediate.value = get_next(short, insn); - insn->immediate.nbytes = 2; + insn_field_set(&insn->immediate, get_next(short, insn), 2); break; case INAT_IMM_DWORD: - insn->immediate.value = get_next(int, insn); - insn->immediate.nbytes = 4; + insn_field_set(&insn->immediate, get_next(int, insn), 4); break; case INAT_IMM_QWORD: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; - insn->immediate2.value = get_next(int, insn); - insn->immediate2.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); + insn_field_set(&insn->immediate2, get_next(int, insn), 4); break; case INAT_IMM_PTR: if (!__get_immptr(insn)) @@ -599,8 +593,7 @@ void insn_get_immediate(struct insn *insn) goto err_out; } if (inat_has_second_immediate(insn->attr)) { - insn->immediate2.value = get_next(signed char, insn); - insn->immediate2.nbytes = 1; + insn_field_set(&insn->immediate2, get_next(signed char, insn), 1); } done: insn->immediate.got = 1; diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S index b4c43a9b1483..f6fb1d218dcc 100644 --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -28,7 +28,7 @@ SYM_FUNC_START_NOALIGN(__x86_retpoline_\reg) jmp .Lspec_trap_\@ .Ldo_rop_\@: mov %\reg, (%_ASM_SP) - UNWIND_HINT_RET_OFFSET + UNWIND_HINT_FUNC ret SYM_FUNC_END(__x86_retpoline_\reg) diff --git a/arch/x86/platform/pvh/head.S b/arch/x86/platform/pvh/head.S index 43b4d864817e..d2ccadc247e6 100644 --- a/arch/x86/platform/pvh/head.S +++ b/arch/x86/platform/pvh/head.S @@ -16,6 +16,7 @@ #include <asm/boot.h> #include <asm/processor-flags.h> #include <asm/msr.h> +#include <asm/nospec-branch.h> #include <xen/interface/elfnote.h> __HEAD @@ -105,6 +106,7 @@ SYM_CODE_START_LOCAL(pvh_start_xen) /* startup_64 expects boot_params in %rsi. */ mov $_pa(pvh_bootparams), %rsi mov $_pa(startup_64), %rax + ANNOTATE_RETPOLINE_SAFE jmp *%rax #else /* CONFIG_X86_64 */ diff --git a/arch/x86/power/Makefile b/arch/x86/power/Makefile index 6907b523e856..3ff80156f21a 100644 --- a/arch/x86/power/Makefile +++ b/arch/x86/power/Makefile @@ -1,5 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 -OBJECT_FILES_NON_STANDARD_hibernate_asm_$(BITS).o := y # __restore_processor_state() restores %gs after S3 resume and so should not # itself be stack-protected diff --git a/arch/x86/power/hibernate_asm_64.S b/arch/x86/power/hibernate_asm_64.S index 7918b8415f13..d9bed596d849 100644 --- a/arch/x86/power/hibernate_asm_64.S +++ b/arch/x86/power/hibernate_asm_64.S @@ -21,6 +21,53 @@ #include <asm/asm-offsets.h> #include <asm/processor-flags.h> #include <asm/frame.h> +#include <asm/nospec-branch.h> + + /* code below belongs to the image kernel */ + .align PAGE_SIZE +SYM_FUNC_START(restore_registers) + /* go back to the original page tables */ + movq %r9, %cr3 + + /* Flush TLB, including "global" things (vmalloc) */ + movq mmu_cr4_features(%rip), %rax + movq %rax, %rdx + andq $~(X86_CR4_PGE), %rdx + movq %rdx, %cr4; # turn off PGE + movq %cr3, %rcx; # flush TLB + movq %rcx, %cr3 + movq %rax, %cr4; # turn PGE back on + + /* We don't restore %rax, it must be 0 anyway */ + movq $saved_context, %rax + movq pt_regs_sp(%rax), %rsp + movq pt_regs_bp(%rax), %rbp + movq pt_regs_si(%rax), %rsi + movq pt_regs_di(%rax), %rdi + movq pt_regs_bx(%rax), %rbx + movq pt_regs_cx(%rax), %rcx + movq pt_regs_dx(%rax), %rdx + movq pt_regs_r8(%rax), %r8 + movq pt_regs_r9(%rax), %r9 + movq pt_regs_r10(%rax), %r10 + movq pt_regs_r11(%rax), %r11 + movq pt_regs_r12(%rax), %r12 + movq pt_regs_r13(%rax), %r13 + movq pt_regs_r14(%rax), %r14 + movq pt_regs_r15(%rax), %r15 + pushq pt_regs_flags(%rax) + popfq + + /* Saved in save_processor_state. */ + lgdt saved_context_gdt_desc(%rax) + + xorl %eax, %eax + + /* tell the hibernation core that we've just restored the memory */ + movq %rax, in_suspend(%rip) + + ret +SYM_FUNC_END(restore_registers) SYM_FUNC_START(swsusp_arch_suspend) movq $saved_context, %rax @@ -52,7 +99,7 @@ SYM_FUNC_START(swsusp_arch_suspend) ret SYM_FUNC_END(swsusp_arch_suspend) -SYM_CODE_START(restore_image) +SYM_FUNC_START(restore_image) /* prepare to jump to the image kernel */ movq restore_jump_address(%rip), %r8 movq restore_cr3(%rip), %r9 @@ -66,11 +113,12 @@ SYM_CODE_START(restore_image) /* jump to relocated restore code */ movq relocated_restore_code(%rip), %rcx + ANNOTATE_RETPOLINE_SAFE jmpq *%rcx -SYM_CODE_END(restore_image) +SYM_FUNC_END(restore_image) /* code below has been relocated to a safe page */ -SYM_CODE_START(core_restore_code) +SYM_FUNC_START(core_restore_code) /* switch to temporary page tables */ movq %rax, %cr3 /* flush TLB */ @@ -97,51 +145,6 @@ SYM_CODE_START(core_restore_code) .Ldone: /* jump to the restore_registers address from the image header */ + ANNOTATE_RETPOLINE_SAFE jmpq *%r8 -SYM_CODE_END(core_restore_code) - - /* code below belongs to the image kernel */ - .align PAGE_SIZE -SYM_FUNC_START(restore_registers) - /* go back to the original page tables */ - movq %r9, %cr3 - - /* Flush TLB, including "global" things (vmalloc) */ - movq mmu_cr4_features(%rip), %rax - movq %rax, %rdx - andq $~(X86_CR4_PGE), %rdx - movq %rdx, %cr4; # turn off PGE - movq %cr3, %rcx; # flush TLB - movq %rcx, %cr3 - movq %rax, %cr4; # turn PGE back on - - /* We don't restore %rax, it must be 0 anyway */ - movq $saved_context, %rax - movq pt_regs_sp(%rax), %rsp - movq pt_regs_bp(%rax), %rbp - movq pt_regs_si(%rax), %rsi - movq pt_regs_di(%rax), %rdi - movq pt_regs_bx(%rax), %rbx - movq pt_regs_cx(%rax), %rcx - movq pt_regs_dx(%rax), %rdx - movq pt_regs_r8(%rax), %r8 - movq pt_regs_r9(%rax), %r9 - movq pt_regs_r10(%rax), %r10 - movq pt_regs_r11(%rax), %r11 - movq pt_regs_r12(%rax), %r12 - movq pt_regs_r13(%rax), %r13 - movq pt_regs_r14(%rax), %r14 - movq pt_regs_r15(%rax), %r15 - pushq pt_regs_flags(%rax) - popfq - - /* Saved in save_processor_state. */ - lgdt saved_context_gdt_desc(%rax) - - xorl %eax, %eax - - /* tell the hibernation core that we've just restored the memory */ - movq %rax, in_suspend(%rip) - - ret -SYM_FUNC_END(restore_registers) +SYM_FUNC_END(core_restore_code) diff --git a/arch/x86/tools/Makefile b/arch/x86/tools/Makefile index 55b1ab378974..bddfc9a46645 100644 --- a/arch/x86/tools/Makefile +++ b/arch/x86/tools/Makefile @@ -29,14 +29,14 @@ posttest: $(obj)/insn_decoder_test vmlinux $(obj)/insn_sanity hostprogs += insn_decoder_test insn_sanity # -I needed for generated C source and C source which in the kernel tree. -HOSTCFLAGS_insn_decoder_test.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/uapi/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/uapi/ +HOSTCFLAGS_insn_decoder_test.o := -Wall -I$(srctree)/tools/arch/x86/lib/ -I$(srctree)/tools/arch/x86/include/ -I$(objtree)/arch/x86/lib/ -HOSTCFLAGS_insn_sanity.o := -Wall -I$(objtree)/arch/x86/lib/ -I$(srctree)/arch/x86/include/ -I$(srctree)/arch/x86/lib/ -I$(srctree)/include/ +HOSTCFLAGS_insn_sanity.o := -Wall -I$(srctree)/tools/arch/x86/lib/ -I$(srctree)/tools/arch/x86/include/ -I$(objtree)/arch/x86/lib/ # Dependencies are also needed. -$(obj)/insn_decoder_test.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c +$(obj)/insn_decoder_test.o: $(srctree)/tools/arch/x86/lib/insn.c $(srctree)/tools/arch/x86/lib/inat.c $(srctree)/tools/arch/x86/include/asm/inat_types.h $(srctree)/tools/arch/x86/include/asm/inat.h $(srctree)/tools/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c -$(obj)/insn_sanity.o: $(srctree)/arch/x86/lib/insn.c $(srctree)/arch/x86/lib/inat.c $(srctree)/arch/x86/include/asm/inat_types.h $(srctree)/arch/x86/include/asm/inat.h $(srctree)/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c +$(obj)/insn_sanity.o: $(srctree)/tools/arch/x86/lib/insn.c $(srctree)/tools/arch/x86/lib/inat.c $(srctree)/tools/arch/x86/include/asm/inat_types.h $(srctree)/tools/arch/x86/include/asm/inat.h $(srctree)/tools/arch/x86/include/asm/insn.h $(objtree)/arch/x86/lib/inat-tables.c HOST_EXTRACFLAGS += -I$(srctree)/tools/include hostprogs += relocs diff --git a/arch/x86/tools/insn_sanity.c b/arch/x86/tools/insn_sanity.c index 185ceba9d289..c6a0000ae635 100644 --- a/arch/x86/tools/insn_sanity.c +++ b/arch/x86/tools/insn_sanity.c @@ -14,10 +14,6 @@ #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> - -#define unlikely(cond) (cond) -#define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0])) - #include <asm/insn.h> #include <inat.c> #include <insn.c> diff --git a/arch/x86/xen/Makefile b/arch/x86/xen/Makefile index fc5c5ba4aacb..40b5779fce21 100644 --- a/arch/x86/xen/Makefile +++ b/arch/x86/xen/Makefile @@ -1,5 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 -OBJECT_FILES_NON_STANDARD_xen-asm.o := y ifdef CONFIG_FUNCTION_TRACER # Do not profile debug and lowlevel utilities diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 02f31341e435..1e626444712b 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -14,6 +14,7 @@ #include <asm/thread_info.h> #include <asm/asm.h> #include <asm/frame.h> +#include <asm/unwind_hints.h> #include <xen/interface/xen.h> @@ -118,6 +119,7 @@ SYM_FUNC_END(xen_read_cr2_direct); .macro xen_pv_trap name SYM_CODE_START(xen_\name) + UNWIND_HINT_EMPTY pop %rcx pop %r11 jmp \name @@ -157,6 +159,7 @@ xen_pv_trap asm_exc_xen_hypervisor_callback SYM_CODE_START(xen_early_idt_handler_array) i = 0 .rept NUM_EXCEPTION_VECTORS + UNWIND_HINT_EMPTY pop %rcx pop %r11 jmp early_idt_handler_array + i*EARLY_IDT_HANDLER_SIZE @@ -183,6 +186,7 @@ hypercall_iret = hypercall_page + __HYPERVISOR_iret * 32 * rsp->rax } */ SYM_CODE_START(xen_iret) + UNWIND_HINT_EMPTY pushq $0 jmp hypercall_iret SYM_CODE_END(xen_iret) @@ -203,7 +207,8 @@ SYM_CODE_END(xen_iret) */ /* Normal 64-bit system call target */ -SYM_FUNC_START(xen_syscall_target) +SYM_CODE_START(xen_syscall_target) + UNWIND_HINT_EMPTY popq %rcx popq %r11 @@ -216,12 +221,13 @@ SYM_FUNC_START(xen_syscall_target) movq $__USER_CS, 1*8(%rsp) jmp entry_SYSCALL_64_after_hwframe -SYM_FUNC_END(xen_syscall_target) +SYM_CODE_END(xen_syscall_target) #ifdef CONFIG_IA32_EMULATION /* 32-bit compat syscall target */ -SYM_FUNC_START(xen_syscall32_target) +SYM_CODE_START(xen_syscall32_target) + UNWIND_HINT_EMPTY popq %rcx popq %r11 @@ -234,10 +240,11 @@ SYM_FUNC_START(xen_syscall32_target) movq $__USER32_CS, 1*8(%rsp) jmp entry_SYSCALL_compat_after_hwframe -SYM_FUNC_END(xen_syscall32_target) +SYM_CODE_END(xen_syscall32_target) /* 32-bit compat sysenter target */ -SYM_FUNC_START(xen_sysenter_target) +SYM_CODE_START(xen_sysenter_target) + UNWIND_HINT_EMPTY /* * NB: Xen is polite and clears TF from EFLAGS for us. This means * that we don't need to guard against single step exceptions here. @@ -254,17 +261,18 @@ SYM_FUNC_START(xen_sysenter_target) movq $__USER32_CS, 1*8(%rsp) jmp entry_SYSENTER_compat_after_hwframe -SYM_FUNC_END(xen_sysenter_target) +SYM_CODE_END(xen_sysenter_target) #else /* !CONFIG_IA32_EMULATION */ -SYM_FUNC_START_ALIAS(xen_syscall32_target) -SYM_FUNC_START(xen_sysenter_target) +SYM_CODE_START(xen_syscall32_target) +SYM_CODE_START(xen_sysenter_target) + UNWIND_HINT_EMPTY lea 16(%rsp), %rsp /* strip %rcx, %r11 */ mov $-ENOSYS, %rax pushq $0 jmp hypercall_iret -SYM_FUNC_END(xen_sysenter_target) -SYM_FUNC_END_ALIAS(xen_syscall32_target) +SYM_CODE_END(xen_sysenter_target) +SYM_CODE_END(xen_syscall32_target) #endif /* CONFIG_IA32_EMULATION */ diff --git a/arch/x86/xen/xen-head.S b/arch/x86/xen/xen-head.S index 2d7c8f34f56c..cb6538ae2fe0 100644 --- a/arch/x86/xen/xen-head.S +++ b/arch/x86/xen/xen-head.S @@ -68,8 +68,9 @@ SYM_CODE_END(asm_cpu_bringup_and_idle) .balign PAGE_SIZE SYM_CODE_START(hypercall_page) .rept (PAGE_SIZE / 32) - UNWIND_HINT_EMPTY - .skip 32 + UNWIND_HINT_FUNC + .skip 31, 0x90 + ret .endr #define HYPERCALL(n) \ diff --git a/include/linux/objtool.h b/include/linux/objtool.h index 577f51436cf9..7e72d975cb76 100644 --- a/include/linux/objtool.h +++ b/include/linux/objtool.h @@ -29,11 +29,14 @@ struct unwind_hint { * * UNWIND_HINT_TYPE_REGS_PARTIAL: Used in entry code to indicate that * sp_reg+sp_offset points to the iret return frame. + * + * UNWIND_HINT_FUNC: Generate the unwind metadata of a callable function. + * Useful for code which doesn't have an ELF function annotation. */ #define UNWIND_HINT_TYPE_CALL 0 #define UNWIND_HINT_TYPE_REGS 1 #define UNWIND_HINT_TYPE_REGS_PARTIAL 2 -#define UNWIND_HINT_TYPE_RET_OFFSET 3 +#define UNWIND_HINT_TYPE_FUNC 3 #ifdef CONFIG_STACK_VALIDATION @@ -109,6 +112,12 @@ struct unwind_hint { .popsection .endm +.macro STACK_FRAME_NON_STANDARD func:req + .pushsection .discard.func_stack_frame_non_standard, "aw" + .long \func - . + .popsection +.endm + #endif /* __ASSEMBLY__ */ #else /* !CONFIG_STACK_VALIDATION */ @@ -122,6 +131,8 @@ struct unwind_hint { #define ANNOTATE_INTRA_FUNCTION_CALL .macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0 .endm +.macro STACK_FRAME_NON_STANDARD func:req +.endm #endif #endif /* CONFIG_STACK_VALIDATION */ diff --git a/tools/arch/x86/include/asm/insn.h b/tools/arch/x86/include/asm/insn.h index 52c6262e6bfd..cc777c185212 100644 --- a/tools/arch/x86/include/asm/insn.h +++ b/tools/arch/x86/include/asm/insn.h @@ -7,9 +7,12 @@ * Copyright (C) IBM Corporation, 2009 */ +#include <asm/byteorder.h> /* insn_attr_t is defined in inat.h */ #include "inat.h" +#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN) + struct insn_field { union { insn_value_t value; @@ -20,6 +23,48 @@ struct insn_field { unsigned char nbytes; }; +static inline void insn_field_set(struct insn_field *p, insn_value_t v, + unsigned char n) +{ + p->value = v; + p->nbytes = n; +} + +static inline void insn_set_byte(struct insn_field *p, unsigned char n, + insn_byte_t v) +{ + p->bytes[n] = v; +} + +#else + +struct insn_field { + insn_value_t value; + union { + insn_value_t little; + insn_byte_t bytes[4]; + }; + /* !0 if we've run insn_get_xxx() for this field */ + unsigned char got; + unsigned char nbytes; +}; + +static inline void insn_field_set(struct insn_field *p, insn_value_t v, + unsigned char n) +{ + p->value = v; + p->little = __cpu_to_le32(v); + p->nbytes = n; +} + +static inline void insn_set_byte(struct insn_field *p, unsigned char n, + insn_byte_t v) +{ + p->bytes[n] = v; + p->value = __le32_to_cpu(p->little); +} +#endif + struct insn { struct insn_field prefixes; /* * Prefixes diff --git a/tools/arch/x86/include/asm/orc_types.h b/tools/arch/x86/include/asm/orc_types.h index fdbffec4cfde..5a2baf28a1dc 100644 --- a/tools/arch/x86/include/asm/orc_types.h +++ b/tools/arch/x86/include/asm/orc_types.h @@ -40,6 +40,8 @@ #define ORC_REG_MAX 15 #ifndef __ASSEMBLY__ +#include <asm/byteorder.h> + /* * This struct is more or less a vastly simplified version of the DWARF Call * Frame Information standard. It contains only the necessary parts of DWARF @@ -51,10 +53,18 @@ struct orc_entry { s16 sp_offset; s16 bp_offset; +#if defined(__LITTLE_ENDIAN_BITFIELD) unsigned sp_reg:4; unsigned bp_reg:4; unsigned type:2; unsigned end:1; +#elif defined(__BIG_ENDIAN_BITFIELD) + unsigned bp_reg:4; + unsigned sp_reg:4; + unsigned unused:5; + unsigned end:1; + unsigned type:2; +#endif } __packed; #endif /* __ASSEMBLY__ */ diff --git a/tools/arch/x86/lib/insn.c b/tools/arch/x86/lib/insn.c index 0151dfc6da61..3d9355ed1246 100644 --- a/tools/arch/x86/lib/insn.c +++ b/tools/arch/x86/lib/insn.c @@ -5,6 +5,7 @@ * Copyright (C) IBM Corporation, 2002, 2004, 2009 */ +#include <linux/kernel.h> #ifdef __KERNEL__ #include <linux/string.h> #else @@ -15,15 +16,28 @@ #include "../include/asm/emulate_prefix.h" +#define leXX_to_cpu(t, r) \ +({ \ + __typeof__(t) v; \ + switch (sizeof(t)) { \ + case 4: v = le32_to_cpu(r); break; \ + case 2: v = le16_to_cpu(r); break; \ + case 1: v = r; break; \ + default: \ + BUILD_BUG(); break; \ + } \ + v; \ +}) + /* Verify next sizeof(t) bytes can be on the same instruction */ #define validate_next(t, insn, n) \ ((insn)->next_byte + sizeof(t) + n <= (insn)->end_kaddr) #define __get_next(t, insn) \ - ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; }) + ({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); leXX_to_cpu(t, r); }) #define __peek_nbyte_next(t, insn, n) \ - ({ t r = *(t*)((insn)->next_byte + n); r; }) + ({ t r = *(t*)((insn)->next_byte + n); leXX_to_cpu(t, r); }) #define get_next(t, insn) \ ({ if (unlikely(!validate_next(t, insn, 0))) goto err_out; __get_next(t, insn); }) @@ -147,9 +161,9 @@ found: b = insn->prefixes.bytes[3]; for (i = 0; i < nb; i++) if (prefixes->bytes[i] == lb) - prefixes->bytes[i] = b; + insn_set_byte(prefixes, i, b); } - insn->prefixes.bytes[3] = lb; + insn_set_byte(&insn->prefixes, 3, lb); } /* Decode REX prefix */ @@ -157,8 +171,7 @@ found: b = peek_next(insn_byte_t, insn); attr = inat_get_opcode_attribute(b); if (inat_is_rex_prefix(attr)) { - insn->rex_prefix.value = b; - insn->rex_prefix.nbytes = 1; + insn_field_set(&insn->rex_prefix, b, 1); insn->next_byte++; if (X86_REX_W(b)) /* REX.W overrides opnd_size */ @@ -181,13 +194,13 @@ found: if (X86_MODRM_MOD(b2) != 3) goto vex_end; } - insn->vex_prefix.bytes[0] = b; - insn->vex_prefix.bytes[1] = b2; + insn_set_byte(&insn->vex_prefix, 0, b); + insn_set_byte(&insn->vex_prefix, 1, b2); if (inat_is_evex_prefix(attr)) { b2 = peek_nbyte_next(insn_byte_t, insn, 2); - insn->vex_prefix.bytes[2] = b2; + insn_set_byte(&insn->vex_prefix, 2, b2); b2 = peek_nbyte_next(insn_byte_t, insn, 3); - insn->vex_prefix.bytes[3] = b2; + insn_set_byte(&insn->vex_prefix, 3, b2); insn->vex_prefix.nbytes = 4; insn->next_byte += 4; if (insn->x86_64 && X86_VEX_W(b2)) @@ -195,7 +208,7 @@ found: insn->opnd_bytes = 8; } else if (inat_is_vex3_prefix(attr)) { b2 = peek_nbyte_next(insn_byte_t, insn, 2); - insn->vex_prefix.bytes[2] = b2; + insn_set_byte(&insn->vex_prefix, 2, b2); insn->vex_prefix.nbytes = 3; insn->next_byte += 3; if (insn->x86_64 && X86_VEX_W(b2)) @@ -207,7 +220,7 @@ found: * Makes it easier to decode vex.W, vex.vvvv, * vex.L and vex.pp. Masking with 0x7f sets vex.W == 0. */ - insn->vex_prefix.bytes[2] = b2 & 0x7f; + insn_set_byte(&insn->vex_prefix, 2, b2 & 0x7f); insn->vex_prefix.nbytes = 2; insn->next_byte += 2; } @@ -243,7 +256,7 @@ void insn_get_opcode(struct insn *insn) /* Get first opcode */ op = get_next(insn_byte_t, insn); - opcode->bytes[0] = op; + insn_set_byte(opcode, 0, op); opcode->nbytes = 1; /* Check if there is VEX prefix or not */ @@ -295,8 +308,7 @@ void insn_get_modrm(struct insn *insn) if (inat_has_modrm(insn->attr)) { mod = get_next(insn_byte_t, insn); - modrm->value = mod; - modrm->nbytes = 1; + insn_field_set(modrm, mod, 1); if (inat_is_group(insn->attr)) { pfx_id = insn_last_prefix_id(insn); insn->attr = inat_get_group_attribute(mod, pfx_id, @@ -334,7 +346,7 @@ int insn_rip_relative(struct insn *insn) * For rip-relative instructions, the mod field (top 2 bits) * is zero and the r/m field (bottom 3 bits) is 0x5. */ - return (modrm->nbytes && (modrm->value & 0xc7) == 0x5); + return (modrm->nbytes && (modrm->bytes[0] & 0xc7) == 0x5); } /** @@ -353,11 +365,11 @@ void insn_get_sib(struct insn *insn) if (!insn->modrm.got) insn_get_modrm(insn); if (insn->modrm.nbytes) { - modrm = (insn_byte_t)insn->modrm.value; + modrm = insn->modrm.bytes[0]; if (insn->addr_bytes != 2 && X86_MODRM_MOD(modrm) != 3 && X86_MODRM_RM(modrm) == 4) { - insn->sib.value = get_next(insn_byte_t, insn); - insn->sib.nbytes = 1; + insn_field_set(&insn->sib, + get_next(insn_byte_t, insn), 1); } } insn->sib.got = 1; @@ -407,19 +419,18 @@ void insn_get_displacement(struct insn *insn) if (mod == 3) goto out; if (mod == 1) { - insn->displacement.value = get_next(signed char, insn); - insn->displacement.nbytes = 1; + insn_field_set(&insn->displacement, + get_next(signed char, insn), 1); } else if (insn->addr_bytes == 2) { if ((mod == 0 && rm == 6) || mod == 2) { - insn->displacement.value = - get_next(short, insn); - insn->displacement.nbytes = 2; + insn_field_set(&insn->displacement, + get_next(short, insn), 2); } } else { if ((mod == 0 && rm == 5) || mod == 2 || (mod == 0 && base == 5)) { - insn->displacement.value = get_next(int, insn); - insn->displacement.nbytes = 4; + insn_field_set(&insn->displacement, + get_next(int, insn), 4); } } } @@ -435,18 +446,14 @@ static int __get_moffset(struct insn *insn) { switch (insn->addr_bytes) { case 2: - insn->moffset1.value = get_next(short, insn); - insn->moffset1.nbytes = 2; + insn_field_set(&insn->moffset1, get_next(short, insn), 2); break; case 4: - insn->moffset1.value = get_next(int, insn); - insn->moffset1.nbytes = 4; + insn_field_set(&insn->moffset1, get_next(int, insn), 4); break; case 8: - insn->moffset1.value = get_next(int, insn); - insn->moffset1.nbytes = 4; - insn->moffset2.value = get_next(int, insn); - insn->moffset2.nbytes = 4; + insn_field_set(&insn->moffset1, get_next(int, insn), 4); + insn_field_set(&insn->moffset2, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -464,13 +471,11 @@ static int __get_immv32(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate.value = get_next(short, insn); - insn->immediate.nbytes = 2; + insn_field_set(&insn->immediate, get_next(short, insn), 2); break; case 4: case 8: - insn->immediate.value = get_next(int, insn); - insn->immediate.nbytes = 4; + insn_field_set(&insn->immediate, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -487,18 +492,15 @@ static int __get_immv(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate1.value = get_next(short, insn); - insn->immediate1.nbytes = 2; + insn_field_set(&insn->immediate1, get_next(short, insn), 2); break; case 4: - insn->immediate1.value = get_next(int, insn); + insn_field_set(&insn->immediate1, get_next(int, insn), 4); insn->immediate1.nbytes = 4; break; case 8: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; - insn->immediate2.value = get_next(int, insn); - insn->immediate2.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); + insn_field_set(&insn->immediate2, get_next(int, insn), 4); break; default: /* opnd_bytes must be modified manually */ goto err_out; @@ -515,12 +517,10 @@ static int __get_immptr(struct insn *insn) { switch (insn->opnd_bytes) { case 2: - insn->immediate1.value = get_next(short, insn); - insn->immediate1.nbytes = 2; + insn_field_set(&insn->immediate1, get_next(short, insn), 2); break; case 4: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); break; case 8: /* ptr16:64 is not exist (no segment) */ @@ -528,8 +528,7 @@ static int __get_immptr(struct insn *insn) default: /* opnd_bytes must be modified manually */ goto err_out; } - insn->immediate2.value = get_next(unsigned short, insn); - insn->immediate2.nbytes = 2; + insn_field_set(&insn->immediate2, get_next(unsigned short, insn), 2); insn->immediate1.got = insn->immediate2.got = 1; return 1; @@ -565,22 +564,17 @@ void insn_get_immediate(struct insn *insn) switch (inat_immediate_size(insn->attr)) { case INAT_IMM_BYTE: - insn->immediate.value = get_next(signed char, insn); - insn->immediate.nbytes = 1; + insn_field_set(&insn->immediate, get_next(signed char, insn), 1); break; case INAT_IMM_WORD: - insn->immediate.value = get_next(short, insn); - insn->immediate.nbytes = 2; + insn_field_set(&insn->immediate, get_next(short, insn), 2); break; case INAT_IMM_DWORD: - insn->immediate.value = get_next(int, insn); - insn->immediate.nbytes = 4; + insn_field_set(&insn->immediate, get_next(int, insn), 4); break; case INAT_IMM_QWORD: - insn->immediate1.value = get_next(int, insn); - insn->immediate1.nbytes = 4; - insn->immediate2.value = get_next(int, insn); - insn->immediate2.nbytes = 4; + insn_field_set(&insn->immediate1, get_next(int, insn), 4); + insn_field_set(&insn->immediate2, get_next(int, insn), 4); break; case INAT_IMM_PTR: if (!__get_immptr(insn)) @@ -599,8 +593,7 @@ void insn_get_immediate(struct insn *insn) goto err_out; } if (inat_has_second_immediate(insn->attr)) { - insn->immediate2.value = get_next(signed char, insn); - insn->immediate2.nbytes = 1; + insn_field_set(&insn->immediate2, get_next(signed char, insn), 1); } done: insn->immediate.got = 1; diff --git a/tools/include/linux/objtool.h b/tools/include/linux/objtool.h index 577f51436cf9..7e72d975cb76 100644 --- a/tools/include/linux/objtool.h +++ b/tools/include/linux/objtool.h @@ -29,11 +29,14 @@ struct unwind_hint { * * UNWIND_HINT_TYPE_REGS_PARTIAL: Used in entry code to indicate that * sp_reg+sp_offset points to the iret return frame. + * + * UNWIND_HINT_FUNC: Generate the unwind metadata of a callable function. + * Useful for code which doesn't have an ELF function annotation. */ #define UNWIND_HINT_TYPE_CALL 0 #define UNWIND_HINT_TYPE_REGS 1 #define UNWIND_HINT_TYPE_REGS_PARTIAL 2 -#define UNWIND_HINT_TYPE_RET_OFFSET 3 +#define UNWIND_HINT_TYPE_FUNC 3 #ifdef CONFIG_STACK_VALIDATION @@ -109,6 +112,12 @@ struct unwind_hint { .popsection .endm +.macro STACK_FRAME_NON_STANDARD func:req + .pushsection .discard.func_stack_frame_non_standard, "aw" + .long \func - . + .popsection +.endm + #endif /* __ASSEMBLY__ */ #else /* !CONFIG_STACK_VALIDATION */ @@ -122,6 +131,8 @@ struct unwind_hint { #define ANNOTATE_INTRA_FUNCTION_CALL .macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0 .endm +.macro STACK_FRAME_NON_STANDARD func:req +.endm #endif #endif /* CONFIG_STACK_VALIDATION */ diff --git a/tools/objtool/.gitignore b/tools/objtool/.gitignore index 45cefda24c7b..14236db3677f 100644 --- a/tools/objtool/.gitignore +++ b/tools/objtool/.gitignore @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0-only arch/x86/lib/inat-tables.c -objtool +/objtool fixdep diff --git a/tools/objtool/Documentation/stack-validation.txt b/tools/objtool/Documentation/stack-validation.txt index 0542e46c7552..30f38fdc0d56 100644 --- a/tools/objtool/Documentation/stack-validation.txt +++ b/tools/objtool/Documentation/stack-validation.txt @@ -315,13 +315,15 @@ they mean, and suggestions for how to fix them. function tracing inserts additional calls, which is not obvious from the sources). -10. file.o: warning: func()+0x5c: alternative modifies stack - - This means that an alternative includes instructions that modify the - stack. The problem is that there is only one ORC unwind table, this means - that the ORC unwind entries must be valid for each of the alternatives. - The easiest way to enforce this is to ensure alternatives do not contain - any ORC entries, which in turn implies the above constraint. +10. file.o: warning: func()+0x5c: stack layout conflict in alternatives + + This means that in the use of the alternative() or ALTERNATIVE() + macro, the code paths have conflicting modifications to the stack. + The problem is that there is only one ORC unwind table, which means + that the ORC unwind entries must be consistent for all possible + instruction boundaries regardless of which code has been patched. + This limitation can be overcome by massaging the alternatives with + NOPs to shift the stack changes around so they no longer conflict. 11. file.o: warning: unannotated intra-function call diff --git a/tools/objtool/Makefile b/tools/objtool/Makefile index 5cdb19036d7f..92ce4fce7bc7 100644 --- a/tools/objtool/Makefile +++ b/tools/objtool/Makefile @@ -27,6 +27,7 @@ all: $(OBJTOOL) INCLUDES := -I$(srctree)/tools/include \ -I$(srctree)/tools/arch/$(HOSTARCH)/include/uapi \ -I$(srctree)/tools/arch/$(SRCARCH)/include \ + -I$(srctree)/tools/objtool/include \ -I$(srctree)/tools/objtool/arch/$(SRCARCH)/include WARNINGS := $(EXTRA_WARNINGS) -Wno-switch-default -Wno-switch-enum -Wno-packed -Wno-nested-externs CFLAGS := -Werror $(WARNINGS) $(KBUILD_HOSTCFLAGS) -g $(INCLUDES) $(LIBELF_FLAGS) @@ -46,10 +47,6 @@ ifeq ($(SRCARCH),x86) SUBCMD_ORC := y endif -ifeq ($(SUBCMD_ORC),y) - CFLAGS += -DINSN_USE_ORC -endif - export SUBCMD_CHECK SUBCMD_ORC export srctree OUTPUT CFLAGS SRCARCH AWK include $(srctree)/tools/build/Makefile.include diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index cde9c36e40ae..549813cff8ab 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -11,11 +11,11 @@ #include "../../../arch/x86/lib/inat.c" #include "../../../arch/x86/lib/insn.c" -#include "../../check.h" -#include "../../elf.h" -#include "../../arch.h" -#include "../../warn.h" #include <asm/orc_types.h> +#include <objtool/check.h> +#include <objtool/elf.h> +#include <objtool/arch.h> +#include <objtool/warn.h> static unsigned char op_to_cfi_reg[][2] = { {CFI_AX, CFI_R8}, @@ -222,15 +222,38 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, break; case 0x89: - if (rex_w && !rex_r && modrm_mod == 3 && modrm_reg == 4) { + if (rex_w && !rex_r && modrm_reg == 4) { - /* mov %rsp, reg */ - ADD_OP(op) { - op->src.type = OP_SRC_REG; - op->src.reg = CFI_SP; - op->dest.type = OP_DEST_REG; - op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b]; + if (modrm_mod == 3) { + /* mov %rsp, reg */ + ADD_OP(op) { + op->src.type = OP_SRC_REG; + op->src.reg = CFI_SP; + op->dest.type = OP_DEST_REG; + op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b]; + } + break; + + } else { + /* skip nontrivial SIB */ + if (modrm_rm == 4 && !(sib == 0x24 && rex_b == rex_x)) + break; + + /* skip RIP relative displacement */ + if (modrm_rm == 5 && modrm_mod == 0) + break; + + /* mov %rsp, disp(%reg) */ + ADD_OP(op) { + op->src.type = OP_SRC_REG; + op->src.reg = CFI_SP; + op->dest.type = OP_DEST_REG_INDIRECT; + op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b]; + op->dest.offset = insn.displacement.value; + } + break; } + break; } @@ -259,8 +282,10 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, op->dest.reg = CFI_BP; op->dest.offset = insn.displacement.value; } + break; + } - } else if (rex_w && !rex_b && modrm_rm == 4 && sib == 0x24) { + if (rex_w && !rex_b && modrm_rm == 4 && sib == 0x24) { /* mov reg, disp(%rsp) */ ADD_OP(op) { @@ -270,6 +295,7 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, op->dest.reg = CFI_SP; op->dest.offset = insn.displacement.value; } + break; } break; @@ -563,8 +589,8 @@ void arch_initial_func_cfi_state(struct cfi_init_state *state) state->cfa.offset = 8; /* initial RA (return address) */ - state->regs[16].base = CFI_CFA; - state->regs[16].offset = -8; + state->regs[CFI_RA].base = CFI_CFA; + state->regs[CFI_RA].offset = -8; } const char *arch_nop_insn(int len) diff --git a/tools/objtool/arch/x86/include/cfi_regs.h b/tools/objtool/arch/x86/include/arch/cfi_regs.h index 79bc517efba8..79bc517efba8 100644 --- a/tools/objtool/arch/x86/include/cfi_regs.h +++ b/tools/objtool/arch/x86/include/arch/cfi_regs.h diff --git a/tools/objtool/arch/x86/include/arch_elf.h b/tools/objtool/arch/x86/include/arch/elf.h index 69cc4264b28a..69cc4264b28a 100644 --- a/tools/objtool/arch/x86/include/arch_elf.h +++ b/tools/objtool/arch/x86/include/arch/elf.h diff --git a/tools/objtool/arch/x86/include/arch/endianness.h b/tools/objtool/arch/x86/include/arch/endianness.h new file mode 100644 index 000000000000..7c362527da20 --- /dev/null +++ b/tools/objtool/arch/x86/include/arch/endianness.h @@ -0,0 +1,9 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _ARCH_ENDIANNESS_H +#define _ARCH_ENDIANNESS_H + +#include <endian.h> + +#define __TARGET_BYTE_ORDER __LITTLE_ENDIAN + +#endif /* _ARCH_ENDIANNESS_H */ diff --git a/tools/objtool/arch/x86/include/arch_special.h b/tools/objtool/arch/x86/include/arch/special.h index d818b2bffa02..d818b2bffa02 100644 --- a/tools/objtool/arch/x86/include/arch_special.h +++ b/tools/objtool/arch/x86/include/arch/special.h diff --git a/tools/objtool/arch/x86/special.c b/tools/objtool/arch/x86/special.c index fd4af88c0ea5..e707d9bcd161 100644 --- a/tools/objtool/arch/x86/special.c +++ b/tools/objtool/arch/x86/special.c @@ -1,8 +1,8 @@ // SPDX-License-Identifier: GPL-2.0-or-later #include <string.h> -#include "../../special.h" -#include "../../builtin.h" +#include <objtool/special.h> +#include <objtool/builtin.h> #define X86_FEATURE_POPCNT (4 * 32 + 23) #define X86_FEATURE_SMAP (9 * 32 + 20) @@ -48,7 +48,7 @@ bool arch_support_alt_relocation(struct special_alt *special_alt, * replacement group. */ return insn->offset == special_alt->new_off && - (insn->type == INSN_CALL || is_static_jump(insn)); + (insn->type == INSN_CALL || is_jump(insn)); } /* diff --git a/tools/objtool/builtin-check.c b/tools/objtool/builtin-check.c index c6d199bfd0ae..f47951e19c9d 100644 --- a/tools/objtool/builtin-check.c +++ b/tools/objtool/builtin-check.c @@ -15,8 +15,8 @@ #include <subcmd/parse-options.h> #include <string.h> -#include "builtin.h" -#include "objtool.h" +#include <objtool/builtin.h> +#include <objtool/objtool.h> bool no_fp, no_unreachable, retpoline, module, backtrace, uaccess, stats, validate_dup, vmlinux; diff --git a/tools/objtool/builtin-orc.c b/tools/objtool/builtin-orc.c index 7b31121fa60b..8273bbf7cebb 100644 --- a/tools/objtool/builtin-orc.c +++ b/tools/objtool/builtin-orc.c @@ -13,8 +13,8 @@ */ #include <string.h> -#include "builtin.h" -#include "objtool.h" +#include <objtool/builtin.h> +#include <objtool/objtool.h> static const char *orc_usage[] = { "objtool orc generate [<options>] file.o", @@ -51,11 +51,7 @@ int cmd_orc(int argc, const char **argv) if (list_empty(&file->insn_list)) return 0; - ret = create_orc(file); - if (ret) - return ret; - - ret = create_orc_sections(file); + ret = orc_create(file); if (ret) return ret; diff --git a/tools/objtool/check.c b/tools/objtool/check.c index f2e5e5ce1a05..331a763d8775 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -6,21 +6,20 @@ #include <string.h> #include <stdlib.h> -#include "builtin.h" -#include "cfi.h" -#include "arch.h" -#include "check.h" -#include "special.h" -#include "warn.h" -#include "arch_elf.h" +#include <arch/elf.h> +#include <objtool/builtin.h> +#include <objtool/cfi.h> +#include <objtool/arch.h> +#include <objtool/check.h> +#include <objtool/special.h> +#include <objtool/warn.h> +#include <objtool/endianness.h> #include <linux/objtool.h> #include <linux/hashtable.h> #include <linux/kernel.h> #include <linux/static_call_types.h> -#define FAKE_JUMP_OFFSET -1 - struct alternative { struct list_head list; struct instruction *insn; @@ -111,15 +110,20 @@ static struct instruction *prev_insn_same_sym(struct objtool_file *file, static bool is_sibling_call(struct instruction *insn) { + /* + * Assume only ELF functions can make sibling calls. This ensures + * sibling call detection consistency between vmlinux.o and individual + * objects. + */ + if (!insn->func) + return false; + /* An indirect jump is either a sibling call or a jump to a table. */ if (insn->type == INSN_JUMP_DYNAMIC) return list_empty(&insn->alts); - if (!is_static_jump(insn)) - return false; - /* add_jump_destinations() sets insn->call_dest for sibling calls. */ - return !!insn->call_dest; + return (is_static_jump(insn) && insn->call_dest); } /* @@ -156,6 +160,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "machine_real_restart", "rewind_stack_do_exit", "kunit_try_catch_throw", + "xen_start_kernel", }; if (!func) @@ -787,22 +792,16 @@ static int add_jump_destinations(struct objtool_file *file) if (!is_static_jump(insn)) continue; - if (insn->offset == FAKE_JUMP_OFFSET) - continue; - reloc = find_reloc_by_dest_range(file->elf, insn->sec, - insn->offset, insn->len); + insn->offset, insn->len); if (!reloc) { dest_sec = insn->sec; dest_off = arch_jump_destination(insn); } else if (reloc->sym->type == STT_SECTION) { dest_sec = reloc->sym->sec; dest_off = arch_dest_reloc_offset(reloc->addend); - } else if (reloc->sym->sec->idx) { - dest_sec = reloc->sym->sec; - dest_off = reloc->sym->sym.st_value + - arch_dest_reloc_offset(reloc->addend); - } else if (strstr(reloc->sym->name, "_indirect_thunk_")) { + } else if (!strncmp(reloc->sym->name, "__x86_indirect_thunk_", 21) || + !strncmp(reloc->sym->name, "__x86_retpoline_", 16)) { /* * Retpoline jumps are really dynamic jumps in * disguise, so convert them accordingly. @@ -814,14 +813,21 @@ static int add_jump_destinations(struct objtool_file *file) insn->retpoline_safe = true; continue; - } else { - /* external sibling call */ + } else if (insn->func) { + /* internal or external sibling call (with reloc) */ insn->call_dest = reloc->sym; if (insn->call_dest->static_call_tramp) { list_add_tail(&insn->static_call_node, &file->static_call_list); } continue; + } else if (reloc->sym->sec->idx) { + dest_sec = reloc->sym->sec; + dest_off = reloc->sym->sym.st_value + + arch_dest_reloc_offset(reloc->addend); + } else { + /* non-func asm code jumping to another file */ + continue; } insn->jump_dest = find_insn(file, dest_sec, dest_off); @@ -862,15 +868,15 @@ static int add_jump_destinations(struct objtool_file *file) * case where the parent function's only reference to a * subfunction is through a jump table. */ - if (!strstr(insn->func->name, ".cold.") && - strstr(insn->jump_dest->func->name, ".cold.")) { + if (!strstr(insn->func->name, ".cold") && + strstr(insn->jump_dest->func->name, ".cold")) { insn->func->cfunc = insn->jump_dest->func; insn->jump_dest->func->pfunc = insn->func; } else if (insn->jump_dest->func->pfunc != insn->func->pfunc && insn->jump_dest->offset == insn->jump_dest->func->offset) { - /* internal sibling call */ + /* internal sibling call (without reloc) */ insn->call_dest = insn->jump_dest->func; if (insn->call_dest->static_call_tramp) { list_add_tail(&insn->static_call_node, @@ -983,73 +989,83 @@ static int add_call_destinations(struct objtool_file *file) } /* - * The .alternatives section requires some extra special care, over and above - * what other special sections require: - * - * 1. Because alternatives are patched in-place, we need to insert a fake jump - * instruction at the end so that validate_branch() skips all the original - * replaced instructions when validating the new instruction path. - * - * 2. An added wrinkle is that the new instruction length might be zero. In - * that case the old instructions are replaced with noops. We simulate that - * by creating a fake jump as the only new instruction. - * - * 3. In some cases, the alternative section includes an instruction which - * conditionally jumps to the _end_ of the entry. We have to modify these - * jumps' destinations to point back to .text rather than the end of the - * entry in .altinstr_replacement. + * The .alternatives section requires some extra special care over and above + * other special sections because alternatives are patched in place. */ static int handle_group_alt(struct objtool_file *file, struct special_alt *special_alt, struct instruction *orig_insn, struct instruction **new_insn) { - static unsigned int alt_group_next_index = 1; - struct instruction *last_orig_insn, *last_new_insn, *insn, *fake_jump = NULL; - unsigned int alt_group = alt_group_next_index++; + struct instruction *last_orig_insn, *last_new_insn = NULL, *insn, *nop = NULL; + struct alt_group *orig_alt_group, *new_alt_group; unsigned long dest_off; + + orig_alt_group = malloc(sizeof(*orig_alt_group)); + if (!orig_alt_group) { + WARN("malloc failed"); + return -1; + } + orig_alt_group->cfi = calloc(special_alt->orig_len, + sizeof(struct cfi_state *)); + if (!orig_alt_group->cfi) { + WARN("calloc failed"); + return -1; + } + last_orig_insn = NULL; insn = orig_insn; sec_for_each_insn_from(file, insn) { if (insn->offset >= special_alt->orig_off + special_alt->orig_len) break; - insn->alt_group = alt_group; + insn->alt_group = orig_alt_group; last_orig_insn = insn; } + orig_alt_group->orig_group = NULL; + orig_alt_group->first_insn = orig_insn; + orig_alt_group->last_insn = last_orig_insn; + + + new_alt_group = malloc(sizeof(*new_alt_group)); + if (!new_alt_group) { + WARN("malloc failed"); + return -1; + } - if (next_insn_same_sec(file, last_orig_insn)) { - fake_jump = malloc(sizeof(*fake_jump)); - if (!fake_jump) { + if (special_alt->new_len < special_alt->orig_len) { + /* + * Insert a fake nop at the end to make the replacement + * alt_group the same size as the original. This is needed to + * allow propagate_alt_cfi() to do its magic. When the last + * instruction affects the stack, the instruction after it (the + * nop) will propagate the new state to the shared CFI array. + */ + nop = malloc(sizeof(*nop)); + if (!nop) { WARN("malloc failed"); return -1; } - memset(fake_jump, 0, sizeof(*fake_jump)); - INIT_LIST_HEAD(&fake_jump->alts); - INIT_LIST_HEAD(&fake_jump->stack_ops); - init_cfi_state(&fake_jump->cfi); + memset(nop, 0, sizeof(*nop)); + INIT_LIST_HEAD(&nop->alts); + INIT_LIST_HEAD(&nop->stack_ops); + init_cfi_state(&nop->cfi); - fake_jump->sec = special_alt->new_sec; - fake_jump->offset = FAKE_JUMP_OFFSET; - fake_jump->type = INSN_JUMP_UNCONDITIONAL; - fake_jump->jump_dest = list_next_entry(last_orig_insn, list); - fake_jump->func = orig_insn->func; + nop->sec = special_alt->new_sec; + nop->offset = special_alt->new_off + special_alt->new_len; + nop->len = special_alt->orig_len - special_alt->new_len; + nop->type = INSN_NOP; + nop->func = orig_insn->func; + nop->alt_group = new_alt_group; + nop->ignore = orig_insn->ignore_alts; } if (!special_alt->new_len) { - if (!fake_jump) { - WARN("%s: empty alternative at end of section", - special_alt->orig_sec->name); - return -1; - } - - *new_insn = fake_jump; - return 0; + *new_insn = nop; + goto end; } - last_new_insn = NULL; - alt_group = alt_group_next_index++; insn = *new_insn; sec_for_each_insn_from(file, insn) { struct reloc *alt_reloc; @@ -1061,7 +1077,7 @@ static int handle_group_alt(struct objtool_file *file, insn->ignore = orig_insn->ignore_alts; insn->func = orig_insn->func; - insn->alt_group = alt_group; + insn->alt_group = new_alt_group; /* * Since alternative replacement code is copy/pasted by the @@ -1088,14 +1104,8 @@ static int handle_group_alt(struct objtool_file *file, continue; dest_off = arch_jump_destination(insn); - if (dest_off == special_alt->new_off + special_alt->new_len) { - if (!fake_jump) { - WARN("%s: alternative jump to end of section", - special_alt->orig_sec->name); - return -1; - } - insn->jump_dest = fake_jump; - } + if (dest_off == special_alt->new_off + special_alt->new_len) + insn->jump_dest = next_insn_same_sec(file, last_orig_insn); if (!insn->jump_dest) { WARN_FUNC("can't find alternative jump destination", @@ -1110,9 +1120,13 @@ static int handle_group_alt(struct objtool_file *file, return -1; } - if (fake_jump) - list_add(&fake_jump->list, &last_new_insn->list); - + if (nop) + list_add(&nop->list, &last_new_insn->list); +end: + new_alt_group->orig_group = orig_alt_group; + new_alt_group->first_insn = *new_insn; + new_alt_group->last_insn = nop ? : last_new_insn; + new_alt_group->cfi = orig_alt_group->cfi; return 0; } @@ -1404,13 +1418,20 @@ static int add_jump_table_alts(struct objtool_file *file) return 0; } +static void set_func_state(struct cfi_state *state) +{ + state->cfa = initial_func_cfi.cfa; + memcpy(&state->regs, &initial_func_cfi.regs, + CFI_NUM_REGS * sizeof(struct cfi_reg)); + state->stack_size = initial_func_cfi.cfa.offset; +} + static int read_unwind_hints(struct objtool_file *file) { struct section *sec, *relocsec; struct reloc *reloc; struct unwind_hint *hint; struct instruction *insn; - struct cfi_reg *cfa; int i; sec = find_section_by_name(file->elf, ".discard.unwind_hints"); @@ -1445,22 +1466,20 @@ static int read_unwind_hints(struct objtool_file *file) return -1; } - cfa = &insn->cfi.cfa; + insn->hint = true; - if (hint->type == UNWIND_HINT_TYPE_RET_OFFSET) { - insn->ret_offset = hint->sp_offset; + if (hint->type == UNWIND_HINT_TYPE_FUNC) { + set_func_state(&insn->cfi); continue; } - insn->hint = true; - if (arch_decode_hint_reg(insn, hint->sp_reg)) { WARN_FUNC("unsupported unwind_hint sp base reg %d", insn->sec, insn->offset, hint->sp_reg); return -1; } - cfa->offset = hint->sp_offset; + insn->cfi.cfa.offset = bswap_if_needed(hint->sp_offset); insn->cfi.type = hint->type; insn->cfi.end = hint->end; } @@ -1716,27 +1735,18 @@ static bool is_fentry_call(struct instruction *insn) static bool has_modified_stack_frame(struct instruction *insn, struct insn_state *state) { - u8 ret_offset = insn->ret_offset; struct cfi_state *cfi = &state->cfi; int i; if (cfi->cfa.base != initial_func_cfi.cfa.base || cfi->drap) return true; - if (cfi->cfa.offset != initial_func_cfi.cfa.offset + ret_offset) + if (cfi->cfa.offset != initial_func_cfi.cfa.offset) return true; - if (cfi->stack_size != initial_func_cfi.cfa.offset + ret_offset) + if (cfi->stack_size != initial_func_cfi.cfa.offset) return true; - /* - * If there is a ret offset hint then don't check registers - * because a callee-saved register might have been pushed on - * the stack. - */ - if (ret_offset) - return false; - for (i = 0; i < CFI_NUM_REGS; i++) { if (cfi->regs[i].base != initial_func_cfi.regs[i].base || cfi->regs[i].offset != initial_func_cfi.regs[i].offset) @@ -1746,12 +1756,20 @@ static bool has_modified_stack_frame(struct instruction *insn, struct insn_state return false; } +static bool check_reg_frame_pos(const struct cfi_reg *reg, + int expected_offset) +{ + return reg->base == CFI_CFA && + reg->offset == expected_offset; +} + static bool has_valid_stack_frame(struct insn_state *state) { struct cfi_state *cfi = &state->cfi; - if (cfi->cfa.base == CFI_BP && cfi->regs[CFI_BP].base == CFI_CFA && - cfi->regs[CFI_BP].offset == -16) + if (cfi->cfa.base == CFI_BP && + check_reg_frame_pos(&cfi->regs[CFI_BP], -cfi->cfa.offset) && + check_reg_frame_pos(&cfi->regs[CFI_RA], -cfi->cfa.offset + 8)) return true; if (cfi->drap && cfi->regs[CFI_BP].base == CFI_BP) @@ -1880,8 +1898,7 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, case OP_SRC_REG: if (op->src.reg == CFI_SP && op->dest.reg == CFI_BP && cfa->base == CFI_SP && - regs[CFI_BP].base == CFI_CFA && - regs[CFI_BP].offset == -cfa->offset) { + check_reg_frame_pos(®s[CFI_BP], -cfa->offset)) { /* mov %rsp, %rbp */ cfa->base = op->dest.reg; @@ -1941,6 +1958,38 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, cfa->offset = -cfi->vals[op->src.reg].offset; cfi->stack_size = cfa->offset; + } else if (cfa->base == CFI_SP && + cfi->vals[op->src.reg].base == CFI_SP_INDIRECT && + cfi->vals[op->src.reg].offset == cfa->offset) { + + /* + * Stack swizzle: + * + * 1: mov %rsp, (%[tos]) + * 2: mov %[tos], %rsp + * ... + * 3: pop %rsp + * + * Where: + * + * 1 - places a pointer to the previous + * stack at the Top-of-Stack of the + * new stack. + * + * 2 - switches to the new stack. + * + * 3 - pops the Top-of-Stack to restore + * the original stack. + * + * Note: we set base to SP_INDIRECT + * here and preserve offset. Therefore + * when the unwinder reaches ToS it + * will dereference SP and then add the + * offset to find the next frame, IOW: + * (%rsp) + offset. + */ + cfa->base = CFI_SP_INDIRECT; + } else { cfa->base = CFI_UNDEFINED; cfa->offset = 0; @@ -1966,6 +2015,17 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, break; } + if (!cfi->drap && op->src.reg == CFI_SP && + op->dest.reg == CFI_BP && cfa->base == CFI_SP && + check_reg_frame_pos(®s[CFI_BP], -cfa->offset + op->src.offset)) { + + /* lea disp(%rsp), %rbp */ + cfa->base = CFI_BP; + cfa->offset -= op->src.offset; + cfi->bp_scratch = false; + break; + } + if (op->src.reg == CFI_SP && cfa->base == CFI_SP) { /* drap: lea disp(%rsp), %drap */ @@ -2032,6 +2092,13 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, case OP_SRC_POP: case OP_SRC_POPF: + if (op->dest.reg == CFI_SP && cfa->base == CFI_SP_INDIRECT) { + + /* pop %rsp; # restore from a stack swizzle */ + cfa->base = CFI_SP; + break; + } + if (!cfi->drap && op->dest.reg == cfa->base) { /* pop %rbp */ @@ -2060,6 +2127,14 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, break; case OP_SRC_REG_INDIRECT: + if (!cfi->drap && op->dest.reg == cfa->base && + op->dest.reg == CFI_BP) { + + /* mov disp(%rsp), %rbp */ + cfa->base = CFI_SP; + cfa->offset = cfi->stack_size; + } + if (cfi->drap && op->src.reg == CFI_BP && op->src.offset == cfi->drap_offset) { @@ -2081,6 +2156,12 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, /* mov disp(%rbp), %reg */ /* mov disp(%rsp), %reg */ restore_reg(cfi, op->dest.reg); + + } else if (op->src.reg == CFI_SP && + op->src.offset == regs[op->dest.reg].offset + cfi->stack_size) { + + /* mov disp(%rsp), %reg */ + restore_reg(cfi, op->dest.reg); } break; @@ -2158,6 +2239,18 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, /* mov reg, disp(%rsp) */ save_reg(cfi, op->src.reg, CFI_CFA, op->dest.offset - cfi->cfa.offset); + + } else if (op->dest.reg == CFI_SP) { + + /* mov reg, disp(%rsp) */ + save_reg(cfi, op->src.reg, CFI_CFA, + op->dest.offset - cfi->stack_size); + + } else if (op->src.reg == CFI_SP && op->dest.offset == 0) { + + /* mov %rsp, (%reg); # setup a stack swizzle. */ + cfi->vals[op->dest.reg].base = CFI_SP_INDIRECT; + cfi->vals[op->dest.reg].offset = cfa->offset; } break; @@ -2205,22 +2298,47 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, return 0; } -static int handle_insn_ops(struct instruction *insn, struct insn_state *state) +/* + * The stack layouts of alternatives instructions can sometimes diverge when + * they have stack modifications. That's fine as long as the potential stack + * layouts don't conflict at any given potential instruction boundary. + * + * Flatten the CFIs of the different alternative code streams (both original + * and replacement) into a single shared CFI array which can be used to detect + * conflicts and nicely feed a linear array of ORC entries to the unwinder. + */ +static int propagate_alt_cfi(struct objtool_file *file, struct instruction *insn) { - struct stack_op *op; + struct cfi_state **alt_cfi; + int group_off; - list_for_each_entry(op, &insn->stack_ops, list) { - struct cfi_state old_cfi = state->cfi; - int res; + if (!insn->alt_group) + return 0; - res = update_cfi_state(insn, &state->cfi, op); - if (res) - return res; + alt_cfi = insn->alt_group->cfi; + group_off = insn->offset - insn->alt_group->first_insn->offset; - if (insn->alt_group && memcmp(&state->cfi, &old_cfi, sizeof(struct cfi_state))) { - WARN_FUNC("alternative modifies stack", insn->sec, insn->offset); + if (!alt_cfi[group_off]) { + alt_cfi[group_off] = &insn->cfi; + } else { + if (memcmp(alt_cfi[group_off], &insn->cfi, sizeof(struct cfi_state))) { + WARN_FUNC("stack layout conflict in alternatives", + insn->sec, insn->offset); return -1; } + } + + return 0; +} + +static int handle_insn_ops(struct instruction *insn, struct insn_state *state) +{ + struct stack_op *op; + + list_for_each_entry(op, &insn->stack_ops, list) { + + if (update_cfi_state(insn, &state->cfi, op)) + return 1; if (op->dest.type == OP_DEST_PUSHF) { if (!state->uaccess_stack) { @@ -2410,28 +2528,20 @@ static int validate_return(struct symbol *func, struct instruction *insn, struct return 0; } -/* - * Alternatives should not contain any ORC entries, this in turn means they - * should not contain any CFI ops, which implies all instructions should have - * the same same CFI state. - * - * It is possible to constuct alternatives that have unreachable holes that go - * unreported (because they're NOPs), such holes would result in CFI_UNDEFINED - * states which then results in ORC entries, which we just said we didn't want. - * - * Avoid them by copying the CFI entry of the first instruction into the whole - * alternative. - */ -static void fill_alternative_cfi(struct objtool_file *file, struct instruction *insn) +static struct instruction *next_insn_to_validate(struct objtool_file *file, + struct instruction *insn) { - struct instruction *first_insn = insn; - int alt_group = insn->alt_group; + struct alt_group *alt_group = insn->alt_group; - sec_for_each_insn_continue(file, insn) { - if (insn->alt_group != alt_group) - break; - insn->cfi = first_insn->cfi; - } + /* + * Simulate the fact that alternatives are patched in-place. When the + * end of a replacement alt_group is reached, redirect objtool flow to + * the end of the original alt_group. + */ + if (alt_group && insn == alt_group->last_insn && alt_group->orig_group) + return next_insn_same_sec(file, alt_group->orig_group->last_insn); + + return next_insn_same_sec(file, insn); } /* @@ -2452,7 +2562,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, sec = insn->sec; while (1) { - next_insn = next_insn_same_sec(file, insn); + next_insn = next_insn_to_validate(file, insn); if (file->c_file && func && insn->func && func != insn->func->pfunc) { WARN("%s() falls through to next function %s()", @@ -2485,6 +2595,9 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, insn->visited |= visited; + if (propagate_alt_cfi(file, insn)) + return 1; + if (!insn->ignore_alts && !list_empty(&insn->alts)) { bool skip_orig = false; @@ -2500,9 +2613,6 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, } } - if (insn->alt_group) - fill_alternative_cfi(file, insn); - if (skip_orig) return 0; } @@ -2540,7 +2650,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, case INSN_JUMP_CONDITIONAL: case INSN_JUMP_UNCONDITIONAL: - if (func && is_sibling_call(insn)) { + if (is_sibling_call(insn)) { ret = validate_sibling_call(insn, &state); if (ret) return ret; @@ -2562,7 +2672,7 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, case INSN_JUMP_DYNAMIC: case INSN_JUMP_DYNAMIC_CONDITIONAL: - if (func && is_sibling_call(insn)) { + if (is_sibling_call(insn)) { ret = validate_sibling_call(insn, &state); if (ret) return ret; @@ -2605,15 +2715,19 @@ static int validate_branch(struct objtool_file *file, struct symbol *func, break; case INSN_STD: - if (state.df) + if (state.df) { WARN_FUNC("recursive STD", sec, insn->offset); + return 1; + } state.df = true; break; case INSN_CLD: - if (!state.df && func) + if (!state.df && func) { WARN_FUNC("redundant CLD", sec, insn->offset); + return 1; + } state.df = false; break; @@ -2736,9 +2850,6 @@ static bool ignore_unreachable_insn(struct objtool_file *file, struct instructio !strcmp(insn->sec->name, ".altinstr_aux")) return true; - if (insn->type == INSN_JUMP_UNCONDITIONAL && insn->offset == FAKE_JUMP_OFFSET) - return true; - if (!insn->func) return false; @@ -2824,10 +2935,7 @@ static int validate_section(struct objtool_file *file, struct section *sec) continue; init_insn_state(&state, sec); - state.cfi.cfa = initial_func_cfi.cfa; - memcpy(&state.cfi.regs, &initial_func_cfi.regs, - CFI_NUM_REGS * sizeof(struct cfi_reg)); - state.cfi.stack_size = initial_func_cfi.cfa.offset; + set_func_state(&state.cfi); warnings += validate_symbol(file, sec, func, &state); } diff --git a/tools/objtool/elf.c b/tools/objtool/elf.c index e85988ce04f1..93fa833a49a5 100644 --- a/tools/objtool/elf.c +++ b/tools/objtool/elf.c @@ -15,10 +15,10 @@ #include <string.h> #include <unistd.h> #include <errno.h> -#include "builtin.h" +#include <objtool/builtin.h> -#include "elf.h" -#include "warn.h" +#include <objtool/elf.h> +#include <objtool/warn.h> #define MAX_NAME_LEN 128 @@ -814,25 +814,27 @@ static int elf_rebuild_rel_reloc_section(struct section *sec, int nr) { struct reloc *reloc; int idx = 0, size; - GElf_Rel *relocs; + void *buf; /* Allocate a buffer for relocations */ - size = nr * sizeof(*relocs); - relocs = malloc(size); - if (!relocs) { + size = nr * sizeof(GElf_Rel); + buf = malloc(size); + if (!buf) { perror("malloc"); return -1; } - sec->data->d_buf = relocs; + sec->data->d_buf = buf; sec->data->d_size = size; + sec->data->d_type = ELF_T_REL; sec->sh.sh_size = size; idx = 0; list_for_each_entry(reloc, &sec->reloc_list, list) { - relocs[idx].r_offset = reloc->offset; - relocs[idx].r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); + reloc->rel.r_offset = reloc->offset; + reloc->rel.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); + gelf_update_rel(sec->data, idx, &reloc->rel); idx++; } @@ -843,26 +845,28 @@ static int elf_rebuild_rela_reloc_section(struct section *sec, int nr) { struct reloc *reloc; int idx = 0, size; - GElf_Rela *relocs; + void *buf; /* Allocate a buffer for relocations with addends */ - size = nr * sizeof(*relocs); - relocs = malloc(size); - if (!relocs) { + size = nr * sizeof(GElf_Rela); + buf = malloc(size); + if (!buf) { perror("malloc"); return -1; } - sec->data->d_buf = relocs; + sec->data->d_buf = buf; sec->data->d_size = size; + sec->data->d_type = ELF_T_RELA; sec->sh.sh_size = size; idx = 0; list_for_each_entry(reloc, &sec->reloc_list, list) { - relocs[idx].r_offset = reloc->offset; - relocs[idx].r_addend = reloc->addend; - relocs[idx].r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); + reloc->rela.r_offset = reloc->offset; + reloc->rela.r_addend = reloc->addend; + reloc->rela.r_info = GELF_R_INFO(reloc->sym->idx, reloc->type); + gelf_update_rela(sec->data, idx, &reloc->rela); idx++; } diff --git a/tools/objtool/arch.h b/tools/objtool/include/objtool/arch.h index 4a84c3081b8e..6ff0685f5cc5 100644 --- a/tools/objtool/arch.h +++ b/tools/objtool/include/objtool/arch.h @@ -8,12 +8,8 @@ #include <stdbool.h> #include <linux/list.h> -#include "objtool.h" -#include "cfi.h" - -#ifdef INSN_USE_ORC -#include <asm/orc_types.h> -#endif +#include <objtool/objtool.h> +#include <objtool/cfi.h> enum insn_type { INSN_JUMP_CONDITIONAL, diff --git a/tools/objtool/builtin.h b/tools/objtool/include/objtool/builtin.h index 85c979caa367..85c979caa367 100644 --- a/tools/objtool/builtin.h +++ b/tools/objtool/include/objtool/builtin.h diff --git a/tools/objtool/cfi.h b/tools/objtool/include/objtool/cfi.h index c7c59c6a44ee..fd5cb0bed9bf 100644 --- a/tools/objtool/cfi.h +++ b/tools/objtool/include/objtool/cfi.h @@ -6,7 +6,7 @@ #ifndef _OBJTOOL_CFI_H #define _OBJTOOL_CFI_H -#include "cfi_regs.h" +#include <arch/cfi_regs.h> #define CFI_UNDEFINED -1 #define CFI_CFA -2 diff --git a/tools/objtool/check.h b/tools/objtool/include/objtool/check.h index 5ec00a4b891b..4891ead0e85f 100644 --- a/tools/objtool/check.h +++ b/tools/objtool/include/objtool/check.h @@ -7,8 +7,8 @@ #define _CHECK_H #include <stdbool.h> -#include "cfi.h" -#include "arch.h" +#include <objtool/cfi.h> +#include <objtool/arch.h> struct insn_state { struct cfi_state cfi; @@ -19,6 +19,23 @@ struct insn_state { s8 instr; }; +struct alt_group { + /* + * Pointer from a replacement group to the original group. NULL if it + * *is* the original group. + */ + struct alt_group *orig_group; + + /* First and last instructions in the group */ + struct instruction *first_insn, *last_insn; + + /* + * Byte-offset-addressed len-sized array of pointers to CFI structs. + * This is shared with the other alt_groups in the same alternative. + */ + struct cfi_state **cfi; +}; + struct instruction { struct list_head list; struct hlist_node hash; @@ -33,8 +50,7 @@ struct instruction { bool retpoline_safe; s8 instr; u8 visited; - u8 ret_offset; - int alt_group; + struct alt_group *alt_group; struct symbol *call_dest; struct instruction *jump_dest; struct instruction *first_jump_src; @@ -43,9 +59,6 @@ struct instruction { struct symbol *func; struct list_head stack_ops; struct cfi_state cfi; -#ifdef INSN_USE_ORC - struct orc_entry orc; -#endif }; static inline bool is_static_jump(struct instruction *insn) @@ -54,6 +67,17 @@ static inline bool is_static_jump(struct instruction *insn) insn->type == INSN_JUMP_UNCONDITIONAL; } +static inline bool is_dynamic_jump(struct instruction *insn) +{ + return insn->type == INSN_JUMP_DYNAMIC || + insn->type == INSN_JUMP_DYNAMIC_CONDITIONAL; +} + +static inline bool is_jump(struct instruction *insn) +{ + return is_static_jump(insn) || is_dynamic_jump(insn); +} + struct instruction *find_insn(struct objtool_file *file, struct section *sec, unsigned long offset); diff --git a/tools/objtool/elf.h b/tools/objtool/include/objtool/elf.h index e6890cc70a25..e6890cc70a25 100644 --- a/tools/objtool/elf.h +++ b/tools/objtool/include/objtool/elf.h diff --git a/tools/objtool/include/objtool/endianness.h b/tools/objtool/include/objtool/endianness.h new file mode 100644 index 000000000000..10241341eff3 --- /dev/null +++ b/tools/objtool/include/objtool/endianness.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +#ifndef _OBJTOOL_ENDIANNESS_H +#define _OBJTOOL_ENDIANNESS_H + +#include <arch/endianness.h> +#include <linux/kernel.h> +#include <endian.h> + +#ifndef __TARGET_BYTE_ORDER +#error undefined arch __TARGET_BYTE_ORDER +#endif + +#if __BYTE_ORDER != __TARGET_BYTE_ORDER +#define __NEED_BSWAP 1 +#else +#define __NEED_BSWAP 0 +#endif + +/* + * Does a byte swap if target endianness doesn't match the host, i.e. cross + * compilation for little endian on big endian and vice versa. + * To be used for multi-byte values conversion, which are read from / about + * to be written to a target native endianness ELF file. + */ +#define bswap_if_needed(val) \ +({ \ + __typeof__(val) __ret; \ + switch (sizeof(val)) { \ + case 8: __ret = __NEED_BSWAP ? bswap_64(val) : (val); break; \ + case 4: __ret = __NEED_BSWAP ? bswap_32(val) : (val); break; \ + case 2: __ret = __NEED_BSWAP ? bswap_16(val) : (val); break; \ + default: \ + BUILD_BUG(); break; \ + } \ + __ret; \ +}) + +#endif /* _OBJTOOL_ENDIANNESS_H */ diff --git a/tools/objtool/objtool.h b/tools/objtool/include/objtool/objtool.h index 4125d4578b23..e114642efb65 100644 --- a/tools/objtool/objtool.h +++ b/tools/objtool/include/objtool/objtool.h @@ -10,7 +10,7 @@ #include <linux/list.h> #include <linux/hashtable.h> -#include "elf.h" +#include <objtool/elf.h> #define __weak __attribute__((weak)) @@ -26,7 +26,6 @@ struct objtool_file *objtool_open_read(const char *_objname); int check(struct objtool_file *file); int orc_dump(const char *objname); -int create_orc(struct objtool_file *file); -int create_orc_sections(struct objtool_file *file); +int orc_create(struct objtool_file *file); #endif /* _OBJTOOL_H */ diff --git a/tools/objtool/special.h b/tools/objtool/include/objtool/special.h index abddf38ef334..8a09f4e9d480 100644 --- a/tools/objtool/special.h +++ b/tools/objtool/include/objtool/special.h @@ -7,8 +7,8 @@ #define _SPECIAL_H #include <stdbool.h> -#include "check.h" -#include "elf.h" +#include <objtool/check.h> +#include <objtool/elf.h> #define C_JUMP_TABLE_SECTION ".rodata..c_jump_table" diff --git a/tools/objtool/warn.h b/tools/objtool/include/objtool/warn.h index 7799f60de80a..d99c4675e4a5 100644 --- a/tools/objtool/warn.h +++ b/tools/objtool/include/objtool/warn.h @@ -11,7 +11,7 @@ #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> -#include "elf.h" +#include <objtool/elf.h> extern const char *objname; diff --git a/tools/objtool/objtool.c b/tools/objtool/objtool.c index 9df0cd86d310..e848feb0a5fc 100644 --- a/tools/objtool/objtool.c +++ b/tools/objtool/objtool.c @@ -21,9 +21,9 @@ #include <subcmd/pager.h> #include <linux/kernel.h> -#include "builtin.h" -#include "objtool.h" -#include "warn.h" +#include <objtool/builtin.h> +#include <objtool/objtool.h> +#include <objtool/warn.h> struct cmd_struct { const char *name; diff --git a/tools/objtool/orc_dump.c b/tools/objtool/orc_dump.c index 5e6a95368d35..f5a8508c42d6 100644 --- a/tools/objtool/orc_dump.c +++ b/tools/objtool/orc_dump.c @@ -6,8 +6,9 @@ #include <unistd.h> #include <linux/objtool.h> #include <asm/orc_types.h> -#include "objtool.h" -#include "warn.h" +#include <objtool/objtool.h> +#include <objtool/warn.h> +#include <objtool/endianness.h> static const char *reg_name(unsigned int reg) { @@ -54,7 +55,7 @@ static void print_reg(unsigned int reg, int offset) if (reg == ORC_REG_BP_INDIRECT) printf("(bp%+d)", offset); else if (reg == ORC_REG_SP_INDIRECT) - printf("(sp%+d)", offset); + printf("(sp)%+d", offset); else if (reg == ORC_REG_UNDEFINED) printf("(und)"); else @@ -197,11 +198,11 @@ int orc_dump(const char *_objname) printf(" sp:"); - print_reg(orc[i].sp_reg, orc[i].sp_offset); + print_reg(orc[i].sp_reg, bswap_if_needed(orc[i].sp_offset)); printf(" bp:"); - print_reg(orc[i].bp_reg, orc[i].bp_offset); + print_reg(orc[i].bp_reg, bswap_if_needed(orc[i].bp_offset)); printf(" type:%s end:%d\n", orc_type_name(orc[i].type), orc[i].end); diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c index 9ce68b385a1b..738aa5021bc4 100644 --- a/tools/objtool/orc_gen.c +++ b/tools/objtool/orc_gen.c @@ -9,93 +9,91 @@ #include <linux/objtool.h> #include <asm/orc_types.h> -#include "check.h" -#include "warn.h" +#include <objtool/check.h> +#include <objtool/warn.h> +#include <objtool/endianness.h> -int create_orc(struct objtool_file *file) +static int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi) { - struct instruction *insn; + struct instruction *insn = container_of(cfi, struct instruction, cfi); + struct cfi_reg *bp = &cfi->regs[CFI_BP]; - for_each_insn(file, insn) { - struct orc_entry *orc = &insn->orc; - struct cfi_reg *cfa = &insn->cfi.cfa; - struct cfi_reg *bp = &insn->cfi.regs[CFI_BP]; + memset(orc, 0, sizeof(*orc)); - if (!insn->sec->text) - continue; - - orc->end = insn->cfi.end; - - if (cfa->base == CFI_UNDEFINED) { - orc->sp_reg = ORC_REG_UNDEFINED; - continue; - } + orc->end = cfi->end; - switch (cfa->base) { - case CFI_SP: - orc->sp_reg = ORC_REG_SP; - break; - case CFI_SP_INDIRECT: - orc->sp_reg = ORC_REG_SP_INDIRECT; - break; - case CFI_BP: - orc->sp_reg = ORC_REG_BP; - break; - case CFI_BP_INDIRECT: - orc->sp_reg = ORC_REG_BP_INDIRECT; - break; - case CFI_R10: - orc->sp_reg = ORC_REG_R10; - break; - case CFI_R13: - orc->sp_reg = ORC_REG_R13; - break; - case CFI_DI: - orc->sp_reg = ORC_REG_DI; - break; - case CFI_DX: - orc->sp_reg = ORC_REG_DX; - break; - default: - WARN_FUNC("unknown CFA base reg %d", - insn->sec, insn->offset, cfa->base); - return -1; - } + if (cfi->cfa.base == CFI_UNDEFINED) { + orc->sp_reg = ORC_REG_UNDEFINED; + return 0; + } - switch(bp->base) { - case CFI_UNDEFINED: - orc->bp_reg = ORC_REG_UNDEFINED; - break; - case CFI_CFA: - orc->bp_reg = ORC_REG_PREV_SP; - break; - case CFI_BP: - orc->bp_reg = ORC_REG_BP; - break; - default: - WARN_FUNC("unknown BP base reg %d", - insn->sec, insn->offset, bp->base); - return -1; - } + switch (cfi->cfa.base) { + case CFI_SP: + orc->sp_reg = ORC_REG_SP; + break; + case CFI_SP_INDIRECT: + orc->sp_reg = ORC_REG_SP_INDIRECT; + break; + case CFI_BP: + orc->sp_reg = ORC_REG_BP; + break; + case CFI_BP_INDIRECT: + orc->sp_reg = ORC_REG_BP_INDIRECT; + break; + case CFI_R10: + orc->sp_reg = ORC_REG_R10; + break; + case CFI_R13: + orc->sp_reg = ORC_REG_R13; + break; + case CFI_DI: + orc->sp_reg = ORC_REG_DI; + break; + case CFI_DX: + orc->sp_reg = ORC_REG_DX; + break; + default: + WARN_FUNC("unknown CFA base reg %d", + insn->sec, insn->offset, cfi->cfa.base); + return -1; + } - orc->sp_offset = cfa->offset; - orc->bp_offset = bp->offset; - orc->type = insn->cfi.type; + switch (bp->base) { + case CFI_UNDEFINED: + orc->bp_reg = ORC_REG_UNDEFINED; + break; + case CFI_CFA: + orc->bp_reg = ORC_REG_PREV_SP; + break; + case CFI_BP: + orc->bp_reg = ORC_REG_BP; + break; + default: + WARN_FUNC("unknown BP base reg %d", + insn->sec, insn->offset, bp->base); + return -1; } + orc->sp_offset = cfi->cfa.offset; + orc->bp_offset = bp->offset; + orc->type = cfi->type; + return 0; } -static int create_orc_entry(struct elf *elf, struct section *u_sec, struct section *ip_relocsec, - unsigned int idx, struct section *insn_sec, - unsigned long insn_off, struct orc_entry *o) +static int write_orc_entry(struct elf *elf, struct section *orc_sec, + struct section *ip_rsec, unsigned int idx, + struct section *insn_sec, unsigned long insn_off, + struct orc_entry *o) { struct orc_entry *orc; struct reloc *reloc; /* populate ORC data */ - orc = (struct orc_entry *)u_sec->data->d_buf + idx; + orc = (struct orc_entry *)orc_sec->data->d_buf + idx; memcpy(orc, o, sizeof(*orc)); + orc->sp_offset = bswap_if_needed(orc->sp_offset); + orc->bp_offset = bswap_if_needed(orc->bp_offset); /* populate reloc for ip */ reloc = malloc(sizeof(*reloc)); @@ -114,102 +112,149 @@ static int create_orc_entry(struct elf *elf, struct section *u_sec, struct secti reloc->type = R_X86_64_PC32; reloc->offset = idx * sizeof(int); - reloc->sec = ip_relocsec; + reloc->sec = ip_rsec; elf_add_reloc(elf, reloc); return 0; } -int create_orc_sections(struct objtool_file *file) -{ - struct instruction *insn, *prev_insn; - struct section *sec, *u_sec, *ip_relocsec; - unsigned int idx; +struct orc_list_entry { + struct list_head list; + struct orc_entry orc; + struct section *insn_sec; + unsigned long insn_off; +}; - struct orc_entry empty = { - .sp_reg = ORC_REG_UNDEFINED, - .bp_reg = ORC_REG_UNDEFINED, - .type = UNWIND_HINT_TYPE_CALL, - }; +static int orc_list_add(struct list_head *orc_list, struct orc_entry *orc, + struct section *sec, unsigned long offset) +{ + struct orc_list_entry *entry = malloc(sizeof(*entry)); - sec = find_section_by_name(file->elf, ".orc_unwind"); - if (sec) { - WARN("file already has .orc_unwind section, skipping"); + if (!entry) { + WARN("malloc failed"); return -1; } - /* count the number of needed orcs */ - idx = 0; - for_each_sec(file, sec) { - if (!sec->text) - continue; - - prev_insn = NULL; - sec_for_each_insn(file, sec, insn) { - if (!prev_insn || - memcmp(&insn->orc, &prev_insn->orc, - sizeof(struct orc_entry))) { - idx++; - } - prev_insn = insn; - } - - /* section terminator */ - if (prev_insn) - idx++; - } - if (!idx) - return -1; + entry->orc = *orc; + entry->insn_sec = sec; + entry->insn_off = offset; + list_add_tail(&entry->list, orc_list); + return 0; +} - /* create .orc_unwind_ip and .rela.orc_unwind_ip sections */ - sec = elf_create_section(file->elf, ".orc_unwind_ip", 0, sizeof(int), idx); - if (!sec) - return -1; +static unsigned long alt_group_len(struct alt_group *alt_group) +{ + return alt_group->last_insn->offset + + alt_group->last_insn->len - + alt_group->first_insn->offset; +} - ip_relocsec = elf_create_reloc_section(file->elf, sec, SHT_RELA); - if (!ip_relocsec) - return -1; +int orc_create(struct objtool_file *file) +{ + struct section *sec, *ip_rsec, *orc_sec; + unsigned int nr = 0, idx = 0; + struct orc_list_entry *entry; + struct list_head orc_list; - /* create .orc_unwind section */ - u_sec = elf_create_section(file->elf, ".orc_unwind", 0, - sizeof(struct orc_entry), idx); + struct orc_entry null = { + .sp_reg = ORC_REG_UNDEFINED, + .bp_reg = ORC_REG_UNDEFINED, + .type = UNWIND_HINT_TYPE_CALL, + }; - /* populate sections */ - idx = 0; + /* Build a deduplicated list of ORC entries: */ + INIT_LIST_HEAD(&orc_list); for_each_sec(file, sec) { + struct orc_entry orc, prev_orc = {0}; + struct instruction *insn; + bool empty = true; + if (!sec->text) continue; - prev_insn = NULL; sec_for_each_insn(file, sec, insn) { - if (!prev_insn || memcmp(&insn->orc, &prev_insn->orc, - sizeof(struct orc_entry))) { + struct alt_group *alt_group = insn->alt_group; + int i; - if (create_orc_entry(file->elf, u_sec, ip_relocsec, idx, - insn->sec, insn->offset, - &insn->orc)) + if (!alt_group) { + if (init_orc_entry(&orc, &insn->cfi)) return -1; + if (!memcmp(&prev_orc, &orc, sizeof(orc))) + continue; + if (orc_list_add(&orc_list, &orc, sec, + insn->offset)) + return -1; + nr++; + prev_orc = orc; + empty = false; + continue; + } - idx++; + /* + * Alternatives can have different stack layout + * possibilities (but they shouldn't conflict). + * Instead of traversing the instructions, use the + * alt_group's flattened byte-offset-addressed CFI + * array. + */ + for (i = 0; i < alt_group_len(alt_group); i++) { + struct cfi_state *cfi = alt_group->cfi[i]; + if (!cfi) + continue; + if (init_orc_entry(&orc, cfi)) + return -1; + if (!memcmp(&prev_orc, &orc, sizeof(orc))) + continue; + if (orc_list_add(&orc_list, &orc, insn->sec, + insn->offset + i)) + return -1; + nr++; + prev_orc = orc; + empty = false; } - prev_insn = insn; - } - /* section terminator */ - if (prev_insn) { - if (create_orc_entry(file->elf, u_sec, ip_relocsec, idx, - prev_insn->sec, - prev_insn->offset + prev_insn->len, - &empty)) - return -1; + /* Skip to the end of the alt_group */ + insn = alt_group->last_insn; + } - idx++; + /* Add a section terminator */ + if (!empty) { + orc_list_add(&orc_list, &null, sec, sec->len); + nr++; } } + if (!nr) + return 0; + + /* Create .orc_unwind, .orc_unwind_ip and .rela.orc_unwind_ip sections: */ + sec = find_section_by_name(file->elf, ".orc_unwind"); + if (sec) { + WARN("file already has .orc_unwind section, skipping"); + return -1; + } + orc_sec = elf_create_section(file->elf, ".orc_unwind", 0, + sizeof(struct orc_entry), nr); + if (!orc_sec) + return -1; + + sec = elf_create_section(file->elf, ".orc_unwind_ip", 0, sizeof(int), nr); + if (!sec) + return -1; + ip_rsec = elf_create_reloc_section(file->elf, sec, SHT_RELA); + if (!ip_rsec) + return -1; + + /* Write ORC entries to sections: */ + list_for_each_entry(entry, &orc_list, list) { + if (write_orc_entry(file->elf, orc_sec, ip_rsec, idx++, + entry->insn_sec, entry->insn_off, + &entry->orc)) + return -1; + } - if (elf_rebuild_reloc_section(file->elf, ip_relocsec)) + if (elf_rebuild_reloc_section(file->elf, ip_rsec)) return -1; return 0; diff --git a/tools/objtool/special.c b/tools/objtool/special.c index 1a2420febd08..2c7fbda7b055 100644 --- a/tools/objtool/special.c +++ b/tools/objtool/special.c @@ -11,10 +11,11 @@ #include <stdlib.h> #include <string.h> -#include "builtin.h" -#include "special.h" -#include "warn.h" -#include "arch_special.h" +#include <arch/special.h> +#include <objtool/builtin.h> +#include <objtool/special.h> +#include <objtool/warn.h> +#include <objtool/endianness.h> struct special_entry { const char *sec; @@ -77,8 +78,9 @@ static int get_alt_entry(struct elf *elf, struct special_entry *entry, if (entry->feature) { unsigned short feature; - feature = *(unsigned short *)(sec->data->d_buf + offset + - entry->feature); + feature = bswap_if_needed(*(unsigned short *)(sec->data->d_buf + + offset + + entry->feature)); arch_handle_alternative(feature, alt); } diff --git a/tools/objtool/weak.c b/tools/objtool/weak.c index 7843e9a7a72f..8314e824db4a 100644 --- a/tools/objtool/weak.c +++ b/tools/objtool/weak.c @@ -7,7 +7,7 @@ #include <stdbool.h> #include <errno.h> -#include "objtool.h" +#include <objtool/objtool.h> #define UNSUPPORTED(name) \ ({ \ @@ -25,12 +25,7 @@ int __weak orc_dump(const char *_objname) UNSUPPORTED("orc"); } -int __weak create_orc(struct objtool_file *file) -{ - UNSUPPORTED("orc"); -} - -int __weak create_orc_sections(struct objtool_file *file) +int __weak orc_create(struct objtool_file *file) { UNSUPPORTED("orc"); } |