diff --git a/arch/x86/include/asm/orc_types.h b/arch/x86/include/asm/orc_types.h index d25534940bde..fdbffec4cfde 100644 --- a/arch/x86/include/asm/orc_types.h +++ b/arch/x86/include/asm/orc_types.h @@ -39,27 +39,6 @@ #define ORC_REG_SP_INDIRECT 9 #define ORC_REG_MAX 15 -/* - * ORC_TYPE_CALL: Indicates that sp_reg+sp_offset resolves to PREV_SP (the - * caller's SP right before it made the call). Used for all callable - * functions, i.e. all C code and all callable asm functions. - * - * ORC_TYPE_REGS: Used in entry code to indicate that sp_reg+sp_offset points - * to a fully populated pt_regs from a syscall, interrupt, or exception. - * - * ORC_TYPE_REGS_IRET: Used in entry code to indicate that sp_reg+sp_offset - * points to the iret return frame. - * - * The UNWIND_HINT macros are used only for the unwind_hint struct. They - * aren't used in struct orc_entry due to size and complexity constraints. - * Objtool converts them to real types when it converts the hints to orc - * entries. - */ -#define ORC_TYPE_CALL 0 -#define ORC_TYPE_REGS 1 -#define ORC_TYPE_REGS_IRET 2 -#define UNWIND_HINT_TYPE_RET_OFFSET 3 - #ifndef __ASSEMBLY__ /* * This struct is more or less a vastly simplified version of the DWARF Call @@ -78,19 +57,6 @@ struct orc_entry { unsigned end:1; } __packed; -/* - * This struct is used by asm and inline asm code to manually annotate the - * location of registers on the stack for the ORC unwinder. - * - * Type can be either ORC_TYPE_* or UNWIND_HINT_TYPE_*. - */ -struct unwind_hint { - u32 ip; - s16 sp_offset; - u8 sp_reg; - u8 type; - u8 end; -}; #endif /* __ASSEMBLY__ */ #endif /* _ORC_TYPES_H */ diff --git a/arch/x86/include/asm/unwind_hints.h b/arch/x86/include/asm/unwind_hints.h index 7d903fdb3f43..664d4610d700 100644 --- a/arch/x86/include/asm/unwind_hints.h +++ b/arch/x86/include/asm/unwind_hints.h @@ -1,51 +1,17 @@ #ifndef _ASM_X86_UNWIND_HINTS_H #define _ASM_X86_UNWIND_HINTS_H +#include + #include "orc_types.h" #ifdef __ASSEMBLY__ -/* - * In asm, there are two kinds of code: normal C-type callable functions and - * the rest. The normal callable functions can be called by other code, and - * don't do anything unusual with the stack. Such normal callable functions - * are annotated with the ENTRY/ENDPROC macros. Most asm code falls in this - * category. In this case, no special debugging annotations are needed because - * objtool can automatically generate the ORC data for the ORC unwinder to read - * at runtime. - * - * Anything which doesn't fall into the above category, such as syscall and - * interrupt handlers, tends to not be called directly by other functions, and - * often does unusual non-C-function-type things with the stack pointer. Such - * code needs to be annotated such that objtool can understand it. The - * following CFI hint macros are for this type of code. - * - * These macros provide hints to objtool about the state of the stack at each - * instruction. Objtool starts from the hints and follows the code flow, - * making automatic CFI adjustments when it sees pushes and pops, filling out - * the debuginfo as necessary. It will also warn if it sees any - * inconsistencies. - */ -.macro UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=0 type=ORC_TYPE_CALL end=0 -#ifdef CONFIG_STACK_VALIDATION -.Lunwind_hint_ip_\@: - .pushsection .discard.unwind_hints - /* struct unwind_hint */ - .long .Lunwind_hint_ip_\@ - . - .short \sp_offset - .byte \sp_reg - .byte \type - .byte \end - .balign 4 - .popsection -#endif -.endm - .macro UNWIND_HINT_EMPTY - UNWIND_HINT sp_reg=ORC_REG_UNDEFINED end=1 + UNWIND_HINT sp_reg=ORC_REG_UNDEFINED type=UNWIND_HINT_TYPE_CALL end=1 .endm -.macro UNWIND_HINT_REGS base=%rsp offset=0 indirect=0 extra=1 iret=0 +.macro UNWIND_HINT_REGS base=%rsp offset=0 indirect=0 extra=1 partial=0 .if \base == %rsp .if \indirect .set sp_reg, ORC_REG_SP_INDIRECT @@ -66,24 +32,24 @@ .set sp_offset, \offset - .if \iret - .set type, ORC_TYPE_REGS_IRET + .if \partial + .set type, UNWIND_HINT_TYPE_REGS_PARTIAL .elseif \extra == 0 - .set type, ORC_TYPE_REGS_IRET + .set type, UNWIND_HINT_TYPE_REGS_PARTIAL .set sp_offset, \offset + (16*8) .else - .set type, ORC_TYPE_REGS + .set type, UNWIND_HINT_TYPE_REGS .endif UNWIND_HINT sp_reg=sp_reg sp_offset=sp_offset type=type .endm .macro UNWIND_HINT_IRET_REGS base=%rsp offset=0 - UNWIND_HINT_REGS base=\base offset=\offset iret=1 + UNWIND_HINT_REGS base=\base offset=\offset partial=1 .endm .macro UNWIND_HINT_FUNC sp_offset=8 - UNWIND_HINT sp_offset=\sp_offset + UNWIND_HINT sp_reg=ORC_REG_SP sp_offset=\sp_offset type=UNWIND_HINT_TYPE_CALL .endm /* @@ -92,7 +58,7 @@ * initial_func_cfi. */ .macro UNWIND_HINT_RET_OFFSET sp_offset=8 - UNWIND_HINT type=UNWIND_HINT_TYPE_RET_OFFSET sp_offset=\sp_offset + UNWIND_HINT sp_reg=ORC_REG_SP type=UNWIND_HINT_TYPE_RET_OFFSET sp_offset=\sp_offset .endm #endif /* __ASSEMBLY__ */ diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c index ec88bbe08a32..6a339ce328e0 100644 --- a/arch/x86/kernel/unwind_orc.c +++ b/arch/x86/kernel/unwind_orc.c @@ -1,4 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-only +#include #include #include #include @@ -127,12 +128,12 @@ static struct orc_entry null_orc_entry = { .sp_offset = sizeof(long), .sp_reg = ORC_REG_SP, .bp_reg = ORC_REG_UNDEFINED, - .type = ORC_TYPE_CALL + .type = UNWIND_HINT_TYPE_CALL }; /* Fake frame pointer entry -- used as a fallback for generated code */ static struct orc_entry orc_fp_entry = { - .type = ORC_TYPE_CALL, + .type = UNWIND_HINT_TYPE_CALL, .sp_reg = ORC_REG_BP, .sp_offset = 16, .bp_reg = ORC_REG_PREV_SP, @@ -531,7 +532,7 @@ bool unwind_next_frame(struct unwind_state *state) /* Find IP, SP and possibly regs: */ switch (orc->type) { - case ORC_TYPE_CALL: + case UNWIND_HINT_TYPE_CALL: ip_p = sp - sizeof(long); if (!deref_stack_reg(state, ip_p, &state->ip)) @@ -546,7 +547,7 @@ bool unwind_next_frame(struct unwind_state *state) state->signal = false; break; - case ORC_TYPE_REGS: + case UNWIND_HINT_TYPE_REGS: if (!deref_stack_regs(state, sp, &state->ip, &state->sp)) { orc_warn_current("can't access registers at %pB\n", (void *)orig_ip); @@ -559,7 +560,7 @@ bool unwind_next_frame(struct unwind_state *state) state->signal = true; break; - case ORC_TYPE_REGS_IRET: + case UNWIND_HINT_TYPE_REGS_PARTIAL: if (!deref_stack_iret_regs(state, sp, &state->ip, &state->sp)) { orc_warn_current("can't access iret registers at %pB\n", (void *)orig_ip); diff --git a/include/linux/objtool.h b/include/linux/objtool.h index 15e9997a9fb4..ab82c793c897 100644 --- a/include/linux/objtool.h +++ b/include/linux/objtool.h @@ -2,9 +2,55 @@ #ifndef _LINUX_OBJTOOL_H #define _LINUX_OBJTOOL_H +#ifndef __ASSEMBLY__ + +#include + +/* + * This struct is used by asm and inline asm code to manually annotate the + * location of registers on the stack. + */ +struct unwind_hint { + u32 ip; + s16 sp_offset; + u8 sp_reg; + u8 type; + u8 end; +}; +#endif + +/* + * UNWIND_HINT_TYPE_CALL: Indicates that sp_reg+sp_offset resolves to PREV_SP + * (the caller's SP right before it made the call). Used for all callable + * functions, i.e. all C code and all callable asm functions. + * + * UNWIND_HINT_TYPE_REGS: Used in entry code to indicate that sp_reg+sp_offset + * points to a fully populated pt_regs from a syscall, interrupt, or exception. + * + * UNWIND_HINT_TYPE_REGS_PARTIAL: Used in entry code to indicate that + * sp_reg+sp_offset points to the iret return frame. + */ +#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 + #ifdef CONFIG_STACK_VALIDATION #ifndef __ASSEMBLY__ + +#define UNWIND_HINT(sp_reg, sp_offset, type, end) \ + "987: \n\t" \ + ".pushsection .discard.unwind_hints\n\t" \ + /* struct unwind_hint */ \ + ".long 987b - .\n\t" \ + ".short " __stringify(sp_offset) "\n\t" \ + ".byte " __stringify(sp_reg) "\n\t" \ + ".byte " __stringify(type) "\n\t" \ + ".byte " __stringify(end) "\n\t" \ + ".balign 4 \n\t" \ + ".popsection\n\t" + /* * This macro marks the given function's stack frame as "non-standard", which * tells objtool to ignore the function when doing stack metadata validation. @@ -29,12 +75,54 @@ .long 999b; \ .popsection; +/* + * In asm, there are two kinds of code: normal C-type callable functions and + * the rest. The normal callable functions can be called by other code, and + * don't do anything unusual with the stack. Such normal callable functions + * are annotated with the ENTRY/ENDPROC macros. Most asm code falls in this + * category. In this case, no special debugging annotations are needed because + * objtool can automatically generate the ORC data for the ORC unwinder to read + * at runtime. + * + * Anything which doesn't fall into the above category, such as syscall and + * interrupt handlers, tends to not be called directly by other functions, and + * often does unusual non-C-function-type things with the stack pointer. Such + * code needs to be annotated such that objtool can understand it. The + * following CFI hint macros are for this type of code. + * + * These macros provide hints to objtool about the state of the stack at each + * instruction. Objtool starts from the hints and follows the code flow, + * making automatic CFI adjustments when it sees pushes and pops, filling out + * the debuginfo as necessary. It will also warn if it sees any + * inconsistencies. + */ +.macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0 +.Lunwind_hint_ip_\@: + .pushsection .discard.unwind_hints + /* struct unwind_hint */ + .long .Lunwind_hint_ip_\@ - . + .short \sp_offset + .byte \sp_reg + .byte \type + .byte \end + .balign 4 + .popsection +.endm + #endif /* __ASSEMBLY__ */ #else /* !CONFIG_STACK_VALIDATION */ +#ifndef __ASSEMBLY__ + +#define UNWIND_HINT(sp_reg, sp_offset, type, end) \ + "\n\t" #define STACK_FRAME_NON_STANDARD(func) +#else #define ANNOTATE_INTRA_FUNCTION_CALL +.macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0 +.endm +#endif #endif /* CONFIG_STACK_VALIDATION */ diff --git a/tools/arch/x86/include/asm/orc_types.h b/tools/arch/x86/include/asm/orc_types.h index d25534940bde..fdbffec4cfde 100644 --- a/tools/arch/x86/include/asm/orc_types.h +++ b/tools/arch/x86/include/asm/orc_types.h @@ -39,27 +39,6 @@ #define ORC_REG_SP_INDIRECT 9 #define ORC_REG_MAX 15 -/* - * ORC_TYPE_CALL: Indicates that sp_reg+sp_offset resolves to PREV_SP (the - * caller's SP right before it made the call). Used for all callable - * functions, i.e. all C code and all callable asm functions. - * - * ORC_TYPE_REGS: Used in entry code to indicate that sp_reg+sp_offset points - * to a fully populated pt_regs from a syscall, interrupt, or exception. - * - * ORC_TYPE_REGS_IRET: Used in entry code to indicate that sp_reg+sp_offset - * points to the iret return frame. - * - * The UNWIND_HINT macros are used only for the unwind_hint struct. They - * aren't used in struct orc_entry due to size and complexity constraints. - * Objtool converts them to real types when it converts the hints to orc - * entries. - */ -#define ORC_TYPE_CALL 0 -#define ORC_TYPE_REGS 1 -#define ORC_TYPE_REGS_IRET 2 -#define UNWIND_HINT_TYPE_RET_OFFSET 3 - #ifndef __ASSEMBLY__ /* * This struct is more or less a vastly simplified version of the DWARF Call @@ -78,19 +57,6 @@ struct orc_entry { unsigned end:1; } __packed; -/* - * This struct is used by asm and inline asm code to manually annotate the - * location of registers on the stack for the ORC unwinder. - * - * Type can be either ORC_TYPE_* or UNWIND_HINT_TYPE_*. - */ -struct unwind_hint { - u32 ip; - s16 sp_offset; - u8 sp_reg; - u8 type; - u8 end; -}; #endif /* __ASSEMBLY__ */ #endif /* _ORC_TYPES_H */ diff --git a/tools/include/linux/objtool.h b/tools/include/linux/objtool.h new file mode 100644 index 000000000000..ab82c793c897 --- /dev/null +++ b/tools/include/linux/objtool.h @@ -0,0 +1,129 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _LINUX_OBJTOOL_H +#define _LINUX_OBJTOOL_H + +#ifndef __ASSEMBLY__ + +#include + +/* + * This struct is used by asm and inline asm code to manually annotate the + * location of registers on the stack. + */ +struct unwind_hint { + u32 ip; + s16 sp_offset; + u8 sp_reg; + u8 type; + u8 end; +}; +#endif + +/* + * UNWIND_HINT_TYPE_CALL: Indicates that sp_reg+sp_offset resolves to PREV_SP + * (the caller's SP right before it made the call). Used for all callable + * functions, i.e. all C code and all callable asm functions. + * + * UNWIND_HINT_TYPE_REGS: Used in entry code to indicate that sp_reg+sp_offset + * points to a fully populated pt_regs from a syscall, interrupt, or exception. + * + * UNWIND_HINT_TYPE_REGS_PARTIAL: Used in entry code to indicate that + * sp_reg+sp_offset points to the iret return frame. + */ +#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 + +#ifdef CONFIG_STACK_VALIDATION + +#ifndef __ASSEMBLY__ + +#define UNWIND_HINT(sp_reg, sp_offset, type, end) \ + "987: \n\t" \ + ".pushsection .discard.unwind_hints\n\t" \ + /* struct unwind_hint */ \ + ".long 987b - .\n\t" \ + ".short " __stringify(sp_offset) "\n\t" \ + ".byte " __stringify(sp_reg) "\n\t" \ + ".byte " __stringify(type) "\n\t" \ + ".byte " __stringify(end) "\n\t" \ + ".balign 4 \n\t" \ + ".popsection\n\t" + +/* + * This macro marks the given function's stack frame as "non-standard", which + * tells objtool to ignore the function when doing stack metadata validation. + * It should only be used in special cases where you're 100% sure it won't + * affect the reliability of frame pointers and kernel stack traces. + * + * For more information, see tools/objtool/Documentation/stack-validation.txt. + */ +#define STACK_FRAME_NON_STANDARD(func) \ + static void __used __section(.discard.func_stack_frame_non_standard) \ + *__func_stack_frame_non_standard_##func = func + +#else /* __ASSEMBLY__ */ + +/* + * This macro indicates that the following intra-function call is valid. + * Any non-annotated intra-function call will cause objtool to issue a warning. + */ +#define ANNOTATE_INTRA_FUNCTION_CALL \ + 999: \ + .pushsection .discard.intra_function_calls; \ + .long 999b; \ + .popsection; + +/* + * In asm, there are two kinds of code: normal C-type callable functions and + * the rest. The normal callable functions can be called by other code, and + * don't do anything unusual with the stack. Such normal callable functions + * are annotated with the ENTRY/ENDPROC macros. Most asm code falls in this + * category. In this case, no special debugging annotations are needed because + * objtool can automatically generate the ORC data for the ORC unwinder to read + * at runtime. + * + * Anything which doesn't fall into the above category, such as syscall and + * interrupt handlers, tends to not be called directly by other functions, and + * often does unusual non-C-function-type things with the stack pointer. Such + * code needs to be annotated such that objtool can understand it. The + * following CFI hint macros are for this type of code. + * + * These macros provide hints to objtool about the state of the stack at each + * instruction. Objtool starts from the hints and follows the code flow, + * making automatic CFI adjustments when it sees pushes and pops, filling out + * the debuginfo as necessary. It will also warn if it sees any + * inconsistencies. + */ +.macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0 +.Lunwind_hint_ip_\@: + .pushsection .discard.unwind_hints + /* struct unwind_hint */ + .long .Lunwind_hint_ip_\@ - . + .short \sp_offset + .byte \sp_reg + .byte \type + .byte \end + .balign 4 + .popsection +.endm + +#endif /* __ASSEMBLY__ */ + +#else /* !CONFIG_STACK_VALIDATION */ + +#ifndef __ASSEMBLY__ + +#define UNWIND_HINT(sp_reg, sp_offset, type, end) \ + "\n\t" +#define STACK_FRAME_NON_STANDARD(func) +#else +#define ANNOTATE_INTRA_FUNCTION_CALL +.macro UNWIND_HINT sp_reg:req sp_offset=0 type:req end=0 +.endm +#endif + +#endif /* CONFIG_STACK_VALIDATION */ + +#endif /* _LINUX_OBJTOOL_H */ diff --git a/tools/objtool/check.c b/tools/objtool/check.c index a94ad88d036c..95c6e0d31c0a 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -14,6 +14,7 @@ #include "warn.h" #include "arch_elf.h" +#include #include #include #include @@ -1805,7 +1806,8 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, return 0; } - if (cfi->type == ORC_TYPE_REGS || cfi->type == ORC_TYPE_REGS_IRET) + if (cfi->type == UNWIND_HINT_TYPE_REGS || + cfi->type == UNWIND_HINT_TYPE_REGS_PARTIAL) return update_cfi_state_regs(insn, cfi, op); switch (op->dest.type) { diff --git a/tools/objtool/orc_dump.c b/tools/objtool/orc_dump.c index fca46e006fc2..5e6a95368d35 100644 --- a/tools/objtool/orc_dump.c +++ b/tools/objtool/orc_dump.c @@ -4,6 +4,7 @@ */ #include +#include #include #include "objtool.h" #include "warn.h" @@ -37,12 +38,12 @@ static const char *reg_name(unsigned int reg) static const char *orc_type_name(unsigned int type) { switch (type) { - case ORC_TYPE_CALL: + case UNWIND_HINT_TYPE_CALL: return "call"; - case ORC_TYPE_REGS: + case UNWIND_HINT_TYPE_REGS: return "regs"; - case ORC_TYPE_REGS_IRET: - return "iret"; + case UNWIND_HINT_TYPE_REGS_PARTIAL: + return "regs (partial)"; default: return "?"; } diff --git a/tools/objtool/orc_gen.c b/tools/objtool/orc_gen.c index 22fe4398197f..235663b96adc 100644 --- a/tools/objtool/orc_gen.c +++ b/tools/objtool/orc_gen.c @@ -6,6 +6,9 @@ #include #include +#include +#include + #include "check.h" #include "warn.h" @@ -146,7 +149,7 @@ int create_orc_sections(struct objtool_file *file) struct orc_entry empty = { .sp_reg = ORC_REG_UNDEFINED, .bp_reg = ORC_REG_UNDEFINED, - .type = ORC_TYPE_CALL, + .type = UNWIND_HINT_TYPE_CALL, }; sec = find_section_by_name(file->elf, ".orc_unwind"); diff --git a/tools/objtool/sync-check.sh b/tools/objtool/sync-check.sh index cea1c12607b9..606a4b5e929f 100755 --- a/tools/objtool/sync-check.sh +++ b/tools/objtool/sync-check.sh @@ -6,8 +6,10 @@ if [ -z "$SRCARCH" ]; then exit 1 fi +FILES="include/linux/objtool.h" + if [ "$SRCARCH" = "x86" ]; then -FILES=" +FILES="$FILES arch/x86/include/asm/inat_types.h arch/x86/include/asm/orc_types.h arch/x86/include/asm/emulate_prefix.h