diff options
| -rw-r--r-- | arch/arm64/include/asm/bug.h | 2 | ||||
| -rw-r--r-- | arch/loongarch/include/asm/bug.h | 27 | ||||
| -rw-r--r-- | arch/parisc/include/asm/bug.h | 6 | ||||
| -rw-r--r-- | arch/powerpc/include/asm/bug.h | 12 | ||||
| -rw-r--r-- | arch/riscv/include/asm/bug.h | 10 | ||||
| -rw-r--r-- | arch/s390/include/asm/bug.h | 102 | ||||
| -rw-r--r-- | arch/sh/include/asm/bug.h | 4 | ||||
| -rw-r--r-- | arch/x86/Kconfig | 2 | ||||
| -rw-r--r-- | arch/x86/entry/entry.S | 8 | ||||
| -rw-r--r-- | arch/x86/include/asm/bug.h | 146 | ||||
| -rw-r--r-- | arch/x86/kernel/static_call.c | 13 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 119 | ||||
| -rw-r--r-- | include/asm-generic/bug.h | 80 | ||||
| -rw-r--r-- | include/linux/bug.h | 8 | ||||
| -rw-r--r-- | kernel/panic.c | 16 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 10 | ||||
| -rw-r--r-- | lib/bug.c | 90 |
17 files changed, 477 insertions, 178 deletions
diff --git a/arch/arm64/include/asm/bug.h b/arch/arm64/include/asm/bug.h index 28be048db3f6..bceeaec21fb9 100644 --- a/arch/arm64/include/asm/bug.h +++ b/arch/arm64/include/asm/bug.h @@ -19,7 +19,7 @@ unreachable(); \ } while (0) -#define __WARN_FLAGS(flags) __BUG_FLAGS(BUGFLAG_WARNING|(flags)) +#define __WARN_FLAGS(cond_str, flags) __BUG_FLAGS(BUGFLAG_WARNING|(flags)) #define HAVE_ARCH_BUG diff --git a/arch/loongarch/include/asm/bug.h b/arch/loongarch/include/asm/bug.h index f6f254f2c5db..d090a5bec5eb 100644 --- a/arch/loongarch/include/asm/bug.h +++ b/arch/loongarch/include/asm/bug.h @@ -11,7 +11,7 @@ #else #define __BUGVERBOSE_LOCATION(file, line) \ .pushsection .rodata.str, "aMS", @progbits, 1; \ - 10002: .string file; \ + 10002: .ascii file "\0"; \ .popsection; \ \ .long 10002b - .; \ @@ -20,39 +20,38 @@ #endif #ifndef CONFIG_GENERIC_BUG -#define __BUG_ENTRY(flags) +#define __BUG_ENTRY(cond_str, flags) #else -#define __BUG_ENTRY(flags) \ +#define __BUG_ENTRY(cond_str, flags) \ .pushsection __bug_table, "aw"; \ .align 2; \ 10000: .long 10001f - .; \ - _BUGVERBOSE_LOCATION(__FILE__, __LINE__) \ - .short flags; \ + _BUGVERBOSE_LOCATION(WARN_CONDITION_STR(cond_str) __FILE__, __LINE__) \ + .short flags; \ .popsection; \ 10001: #endif -#define ASM_BUG_FLAGS(flags) \ - __BUG_ENTRY(flags) \ +#define ASM_BUG_FLAGS(cond_str, flags) \ + __BUG_ENTRY(cond_str, flags) \ break BRK_BUG; -#define ASM_BUG() ASM_BUG_FLAGS(0) +#define ASM_BUG() ASM_BUG_FLAGS("", 0) -#define __BUG_FLAGS(flags, extra) \ - asm_inline volatile (__stringify(ASM_BUG_FLAGS(flags)) \ - extra); +#define __BUG_FLAGS(cond_str, flags, extra) \ + asm_inline volatile (__stringify(ASM_BUG_FLAGS(cond_str, flags)) extra); -#define __WARN_FLAGS(flags) \ +#define __WARN_FLAGS(cond_str, flags) \ do { \ instrumentation_begin(); \ - __BUG_FLAGS(BUGFLAG_WARNING|(flags), ANNOTATE_REACHABLE(10001b));\ + __BUG_FLAGS(cond_str, BUGFLAG_WARNING|(flags), ANNOTATE_REACHABLE(10001b));\ instrumentation_end(); \ } while (0) #define BUG() \ do { \ instrumentation_begin(); \ - __BUG_FLAGS(0, ""); \ + __BUG_FLAGS("", 0, ""); \ unreachable(); \ } while (0) diff --git a/arch/parisc/include/asm/bug.h b/arch/parisc/include/asm/bug.h index 833555f74ffa..5aa1623e4f2f 100644 --- a/arch/parisc/include/asm/bug.h +++ b/arch/parisc/include/asm/bug.h @@ -50,7 +50,7 @@ #endif #ifdef CONFIG_DEBUG_BUGVERBOSE -#define __WARN_FLAGS(flags) \ +#define __WARN_FLAGS(cond_str, flags) \ do { \ asm volatile("\n" \ "1:\t" PARISC_BUG_BREAK_ASM "\n" \ @@ -61,12 +61,12 @@ "\t.short %1, %2\n" \ "\t.blockz %3-2*4-2*2\n" \ "\t.popsection" \ - : : "i" (__FILE__), "i" (__LINE__), \ + : : "i" (WARN_CONDITION_STR(cond_str) __FILE__), "i" (__LINE__), \ "i" (BUGFLAG_WARNING|(flags)), \ "i" (sizeof(struct bug_entry)) ); \ } while(0) #else -#define __WARN_FLAGS(flags) \ +#define __WARN_FLAGS(cond_str, flags) \ do { \ asm volatile("\n" \ "1:\t" PARISC_BUG_BREAK_ASM "\n" \ diff --git a/arch/powerpc/include/asm/bug.h b/arch/powerpc/include/asm/bug.h index bbaa7e81f821..0db48977c70c 100644 --- a/arch/powerpc/include/asm/bug.h +++ b/arch/powerpc/include/asm/bug.h @@ -51,11 +51,11 @@ ".previous\n" #endif -#define BUG_ENTRY(insn, flags, ...) \ +#define BUG_ENTRY(cond_str, insn, flags, ...) \ __asm__ __volatile__( \ "1: " insn "\n" \ _EMIT_BUG_ENTRY \ - : : "i" (__FILE__), "i" (__LINE__), \ + : : "i" (WARN_CONDITION_STR(cond_str) __FILE__), "i" (__LINE__), \ "i" (flags), \ "i" (sizeof(struct bug_entry)), \ ##__VA_ARGS__) @@ -67,12 +67,12 @@ */ #define BUG() do { \ - BUG_ENTRY("twi 31, 0, 0", 0); \ + BUG_ENTRY("", "twi 31, 0, 0", 0); \ unreachable(); \ } while (0) #define HAVE_ARCH_BUG -#define __WARN_FLAGS(flags) BUG_ENTRY("twi 31, 0, 0", BUGFLAG_WARNING | (flags)) +#define __WARN_FLAGS(cond_str, flags) BUG_ENTRY(cond_str, "twi 31, 0, 0", BUGFLAG_WARNING | (flags)) #ifdef CONFIG_PPC64 #define BUG_ON(x) do { \ @@ -80,7 +80,7 @@ if (x) \ BUG(); \ } else { \ - BUG_ENTRY(PPC_TLNEI " %4, 0", 0, "r" ((__force long)(x))); \ + BUG_ENTRY(#x, PPC_TLNEI " %4, 0", 0, "r" ((__force long)(x))); \ } \ } while (0) @@ -90,7 +90,7 @@ if (__ret_warn_on) \ __WARN(); \ } else { \ - BUG_ENTRY(PPC_TLNEI " %4, 0", \ + BUG_ENTRY(#x, PPC_TLNEI " %4, 0", \ BUGFLAG_WARNING | BUGFLAG_TAINT(TAINT_WARN), \ "r" (__ret_warn_on)); \ } \ diff --git a/arch/riscv/include/asm/bug.h b/arch/riscv/include/asm/bug.h index 4c03e20ad11f..6f581b84d8fc 100644 --- a/arch/riscv/include/asm/bug.h +++ b/arch/riscv/include/asm/bug.h @@ -60,28 +60,28 @@ typedef u32 bug_insn_t; ".org 2b + " size "\n\t" \ ".popsection" \ -#define __BUG_FLAGS(flags) \ +#define __BUG_FLAGS(cond_str, flags) \ do { \ __asm__ __volatile__ ( \ ARCH_WARN_ASM("%0", "%1", "%2", "%3") \ : \ - : "i" (__FILE__), "i" (__LINE__), \ + : "i" (WARN_CONDITION_STR(cond_str) __FILE__), "i" (__LINE__), \ "i" (flags), \ "i" (sizeof(struct bug_entry))); \ } while (0) #else /* CONFIG_GENERIC_BUG */ -#define __BUG_FLAGS(flags) do { \ +#define __BUG_FLAGS(cond_str, flags) do { \ __asm__ __volatile__ ("ebreak\n"); \ } while (0) #endif /* CONFIG_GENERIC_BUG */ #define BUG() do { \ - __BUG_FLAGS(0); \ + __BUG_FLAGS("", 0); \ unreachable(); \ } while (0) -#define __WARN_FLAGS(flags) __BUG_FLAGS(BUGFLAG_WARNING|(flags)) +#define __WARN_FLAGS(cond_str, flags) __BUG_FLAGS(cond_str, BUGFLAG_WARNING|(flags)) #define ARCH_WARN_REACHABLE diff --git a/arch/s390/include/asm/bug.h b/arch/s390/include/asm/bug.h index c500d45fb465..acb4b13d98c5 100644 --- a/arch/s390/include/asm/bug.h +++ b/arch/s390/include/asm/bug.h @@ -2,69 +2,55 @@ #ifndef _ASM_S390_BUG_H #define _ASM_S390_BUG_H -#include <linux/compiler.h> - -#ifdef CONFIG_BUG - -#ifdef CONFIG_DEBUG_BUGVERBOSE - -#define __EMIT_BUG(x) do { \ - asm_inline volatile( \ - "0: mc 0,0\n" \ - ".section .rodata.str,\"aMS\",@progbits,1\n" \ - "1: .asciz \""__FILE__"\"\n" \ - ".previous\n" \ - ".section __bug_table,\"aw\"\n" \ - "2: .long 0b-.\n" \ - " .long 1b-.\n" \ - " .short %0,%1\n" \ - " .org 2b+%2\n" \ - ".previous\n" \ - : : "i" (__LINE__), \ - "i" (x), \ - "i" (sizeof(struct bug_entry))); \ -} while (0) - -#else /* CONFIG_DEBUG_BUGVERBOSE */ - -#define __EMIT_BUG(x) do { \ - asm_inline volatile( \ - "0: mc 0,0\n" \ - ".section __bug_table,\"aw\"\n" \ - "1: .long 0b-.\n" \ - " .short %0\n" \ - " .org 1b+%1\n" \ - ".previous\n" \ - : : "i" (x), \ - "i" (sizeof(struct bug_entry))); \ +#include <linux/stringify.h> + +#ifndef CONFIG_DEBUG_BUGVERBOSE +#define _BUGVERBOSE_LOCATION(file, line) +#else +#define __BUGVERBOSE_LOCATION(file, line) \ + .pushsection .rodata.str, "aMS", @progbits, 1; \ + 10002: .ascii file "\0"; \ + .popsection; \ + \ + .long 10002b - .; \ + .short line; +#define _BUGVERBOSE_LOCATION(file, line) __BUGVERBOSE_LOCATION(file, line) +#endif + +#ifndef CONFIG_GENERIC_BUG +#define __BUG_ENTRY(cond_str, flags) +#else +#define __BUG_ENTRY(cond_str, flags) \ + .pushsection __bug_table, "aw"; \ + .align 4; \ + 10000: .long 10001f - .; \ + _BUGVERBOSE_LOCATION(WARN_CONDITION_STR(cond_str) __FILE__, __LINE__) \ + .short flags; \ + .popsection; \ + 10001: +#endif + +#define ASM_BUG_FLAGS(cond_str, flags) \ + __BUG_ENTRY(cond_str, flags) \ + mc 0,0 + +#define ASM_BUG() ASM_BUG_FLAGS("", 0) + +#define __BUG_FLAGS(cond_str, flags) \ + asm_inline volatile(__stringify(ASM_BUG_FLAGS(cond_str, flags))); + +#define __WARN_FLAGS(cond_str, flags) \ +do { \ + __BUG_FLAGS(cond_str, BUGFLAG_WARNING|(flags)); \ } while (0) -#endif /* CONFIG_DEBUG_BUGVERBOSE */ - -#define BUG() do { \ - __EMIT_BUG(0); \ - unreachable(); \ +#define BUG() \ +do { \ + __BUG_FLAGS("", 0); \ + unreachable(); \ } while (0) -#define __WARN_FLAGS(flags) do { \ - __EMIT_BUG(BUGFLAG_WARNING|(flags)); \ -} while (0) - -#define WARN_ON(x) ({ \ - int __ret_warn_on = !!(x); \ - if (__builtin_constant_p(__ret_warn_on)) { \ - if (__ret_warn_on) \ - __WARN(); \ - } else { \ - if (unlikely(__ret_warn_on)) \ - __WARN(); \ - } \ - unlikely(__ret_warn_on); \ -}) - #define HAVE_ARCH_BUG -#define HAVE_ARCH_WARN_ON -#endif /* CONFIG_BUG */ #include <asm-generic/bug.h> diff --git a/arch/sh/include/asm/bug.h b/arch/sh/include/asm/bug.h index 05a485c4fabc..891276687355 100644 --- a/arch/sh/include/asm/bug.h +++ b/arch/sh/include/asm/bug.h @@ -52,14 +52,14 @@ do { \ unreachable(); \ } while (0) -#define __WARN_FLAGS(flags) \ +#define __WARN_FLAGS(cond_str, flags) \ do { \ __asm__ __volatile__ ( \ "1:\t.short %O0\n" \ _EMIT_BUG_ENTRY \ : \ : "n" (TRAPA_BUG_OPCODE), \ - "i" (__FILE__), \ + "i" (WARN_CONDITION_STR(cond_str) __FILE__), \ "i" (__LINE__), \ "i" (BUGFLAG_WARNING|(flags)), \ "i" (sizeof(struct bug_entry))); \ diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index c4c21e8d0772..34fb46d5341b 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -381,7 +381,7 @@ config GENERIC_CSUM config GENERIC_BUG def_bool y depends on BUG - select GENERIC_BUG_RELATIVE_POINTERS if X86_64 + select GENERIC_BUG_RELATIVE_POINTERS config GENERIC_BUG_RELATIVE_POINTERS bool diff --git a/arch/x86/entry/entry.S b/arch/x86/entry/entry.S index 8e9a0cc20a4a..772c64ed4523 100644 --- a/arch/x86/entry/entry.S +++ b/arch/x86/entry/entry.S @@ -32,6 +32,14 @@ SYM_FUNC_END(write_ibpb) /* For KVM */ EXPORT_SYMBOL_GPL(write_ibpb); +SYM_FUNC_START(__WARN_trap) + ANNOTATE_NOENDBR + ANNOTATE_REACHABLE + ud1 (%edx), %_ASM_ARG1 + RET +SYM_FUNC_END(__WARN_trap) +EXPORT_SYMBOL(__WARN_trap) + .popsection /* diff --git a/arch/x86/include/asm/bug.h b/arch/x86/include/asm/bug.h index 372f4018880c..ab5bba6cf7f5 100644 --- a/arch/x86/include/asm/bug.h +++ b/arch/x86/include/asm/bug.h @@ -7,6 +7,11 @@ #include <linux/objtool.h> #include <asm/asm.h> +#ifndef __ASSEMBLY__ +struct bug_entry; +extern void __WARN_trap(struct bug_entry *bug, ...); +#endif + /* * Despite that some emulators terminate on UD2, we use it for WARN(). */ @@ -31,53 +36,77 @@ #define BUG_UD2 0xfffe #define BUG_UD1 0xfffd #define BUG_UD1_UBSAN 0xfffc +#define BUG_UD1_WARN 0xfffb #define BUG_UDB 0xffd6 #define BUG_LOCK 0xfff0 #ifdef CONFIG_GENERIC_BUG -#ifdef CONFIG_X86_32 -# define __BUG_REL(val) ".long " val +#ifdef CONFIG_DEBUG_BUGVERBOSE +#define __BUG_ENTRY_VERBOSE(file, line) \ + "\t.long " file " - .\t# bug_entry::file\n" \ + "\t.word " line "\t# bug_entry::line\n" #else -# define __BUG_REL(val) ".long " val " - ." +#define __BUG_ENTRY_VERBOSE(file, line) #endif -#ifdef CONFIG_DEBUG_BUGVERBOSE -#define __BUG_ENTRY(file, line, flags) \ - "2:\t" __BUG_REL("1b") "\t# bug_entry::bug_addr\n" \ - "\t" __BUG_REL(file) "\t# bug_entry::file\n" \ - "\t.word " line "\t# bug_entry::line\n" \ - "\t.word " flags "\t# bug_entry::flags\n" +#if defined(CONFIG_X86_64) || defined(CONFIG_DEBUG_BUGVERBOSE_DETAILED) +#define HAVE_ARCH_BUG_FORMAT +#define __BUG_ENTRY_FORMAT(format) \ + "\t.long " format " - .\t# bug_entry::format\n" #else -#define __BUG_ENTRY(file, line, flags) \ - "2:\t" __BUG_REL("1b") "\t# bug_entry::bug_addr\n" \ - "\t.word " flags "\t# bug_entry::flags\n" +#define __BUG_ENTRY_FORMAT(format) +#endif + +#ifdef CONFIG_X86_64 +#define HAVE_ARCH_BUG_FORMAT_ARGS #endif -#define _BUG_FLAGS_ASM(ins, file, line, flags, size, extra) \ - "1:\t" ins "\n" \ - ".pushsection __bug_table,\"aw\"\n" \ +#define __BUG_ENTRY(format, file, line, flags) \ + "\t.long 1b - ." "\t# bug_entry::bug_addr\n" \ + __BUG_ENTRY_FORMAT(format) \ + __BUG_ENTRY_VERBOSE(file, line) \ + "\t.word " flags "\t# bug_entry::flags\n" + +#define _BUG_FLAGS_ASM(format, file, line, flags, size, extra) \ + ".pushsection __bug_table,\"aw\"\n\t" \ ANNOTATE_DATA_SPECIAL \ - __BUG_ENTRY(file, line, flags) \ + "2:\n\t" \ + __BUG_ENTRY(format, file, line, flags) \ "\t.org 2b + " size "\n" \ ".popsection\n" \ extra -#define _BUG_FLAGS(ins, flags, extra) \ +#ifdef CONFIG_DEBUG_BUGVERBOSE_DETAILED +#define WARN_CONDITION_STR(cond_str) cond_str +#else +#define WARN_CONDITION_STR(cond_str) "" +#endif + +#define _BUG_FLAGS(cond_str, ins, flags, extra) \ do { \ - asm_inline volatile(_BUG_FLAGS_ASM(ins, "%c0", \ - "%c1", "%c2", "%c3", extra) \ - : : "i" (__FILE__), "i" (__LINE__), \ - "i" (flags), \ - "i" (sizeof(struct bug_entry))); \ + asm_inline volatile("1:\t" ins "\n" \ + _BUG_FLAGS_ASM("%c[fmt]", "%c[file]", \ + "%c[line]", "%c[fl]", \ + "%c[size]", extra) \ + : : [fmt] "i" (WARN_CONDITION_STR(cond_str)), \ + [file] "i" (__FILE__), \ + [line] "i" (__LINE__), \ + [fl] "i" (flags), \ + [size] "i" (sizeof(struct bug_entry))); \ } while (0) #define ARCH_WARN_ASM(file, line, flags, size) \ - _BUG_FLAGS_ASM(ASM_UD2, file, line, flags, size, "") + ".pushsection .rodata.str1.1, \"aMS\", @progbits, 1\n" \ + "99:\n" \ + "\t.string \"\"\n" \ + ".popsection\n" \ + "1:\t " ASM_UD2 "\n" \ + _BUG_FLAGS_ASM("99b", file, line, flags, size, "") #else -#define _BUG_FLAGS(ins, flags, extra) asm volatile(ins) +#define _BUG_FLAGS(cond_str, ins, flags, extra) asm volatile(ins) #endif /* CONFIG_GENERIC_BUG */ @@ -85,7 +114,7 @@ do { \ #define BUG() \ do { \ instrumentation_begin(); \ - _BUG_FLAGS(ASM_UD2, 0, ""); \ + _BUG_FLAGS("", ASM_UD2, 0, ""); \ __builtin_unreachable(); \ } while (0) @@ -98,14 +127,69 @@ do { \ #define ARCH_WARN_REACHABLE ANNOTATE_REACHABLE(1b) -#define __WARN_FLAGS(flags) \ -do { \ - __auto_type __flags = BUGFLAG_WARNING|(flags); \ - instrumentation_begin(); \ - _BUG_FLAGS(ASM_UD2, __flags, ARCH_WARN_REACHABLE); \ - instrumentation_end(); \ +#define __WARN_FLAGS(cond_str, flags) \ +do { \ + __auto_type __flags = BUGFLAG_WARNING|(flags); \ + instrumentation_begin(); \ + _BUG_FLAGS(cond_str, ASM_UD2, __flags, ARCH_WARN_REACHABLE); \ + instrumentation_end(); \ +} while (0) + +#ifdef HAVE_ARCH_BUG_FORMAT_ARGS + +#ifndef __ASSEMBLY__ +#include <linux/static_call_types.h> +DECLARE_STATIC_CALL(WARN_trap, __WARN_trap); + +struct pt_regs; +struct sysv_va_list { /* from AMD64 System V ABI */ + unsigned int gp_offset; + unsigned int fp_offset; + void *overflow_arg_area; + void *reg_save_area; +}; +struct arch_va_list { + unsigned long regs[6]; + struct sysv_va_list args; +}; +extern void *__warn_args(struct arch_va_list *args, struct pt_regs *regs); +#endif /* __ASSEMBLY__ */ + +#define __WARN_bug_entry(flags, format) ({ \ + struct bug_entry *bug; \ + asm_inline volatile("lea (2f)(%%rip), %[addr]\n1:\n" \ + _BUG_FLAGS_ASM("%c[fmt]", "%c[file]", \ + "%c[line]", "%c[fl]", \ + "%c[size]", "") \ + : [addr] "=r" (bug) \ + : [fmt] "i" (format), \ + [file] "i" (__FILE__), \ + [line] "i" (__LINE__), \ + [fl] "i" (flags), \ + [size] "i" (sizeof(struct bug_entry))); \ + bug; }) + +#define __WARN_print_arg(flags, format, arg...) \ +do { \ + int __flags = (flags) | BUGFLAG_WARNING | BUGFLAG_ARGS ; \ + static_call_mod(WARN_trap)(__WARN_bug_entry(__flags, format), ## arg); \ + asm (""); /* inhibit tail-call optimization */ \ } while (0) +#define __WARN_printf(taint, fmt, arg...) \ + __WARN_print_arg(BUGFLAG_TAINT(taint), fmt, ## arg) + +#define WARN_ONCE(cond, format, arg...) ({ \ + int __ret_warn_on = !!(cond); \ + if (unlikely(__ret_warn_on)) { \ + __WARN_print_arg(BUGFLAG_ONCE|BUGFLAG_TAINT(TAINT_WARN),\ + format, ## arg); \ + } \ + __ret_warn_on; \ +}) + +#endif /* HAVE_ARCH_BUG_FORMAT_ARGS */ + #include <asm-generic/bug.h> #endif /* _ASM_X86_BUG_H */ diff --git a/arch/x86/kernel/static_call.c b/arch/x86/kernel/static_call.c index 378c388d1b31..2892cdb14563 100644 --- a/arch/x86/kernel/static_call.c +++ b/arch/x86/kernel/static_call.c @@ -26,6 +26,11 @@ static const u8 xor5rax[] = { 0x2e, 0x2e, 0x2e, 0x31, 0xc0 }; static const u8 retinsn[] = { RET_INSN_OPCODE, 0xcc, 0xcc, 0xcc, 0xcc }; +/* + * ud1 (%edx),%rdi -- see __WARN_trap() / decode_bug() + */ +static const u8 warninsn[] = { 0x67, 0x48, 0x0f, 0xb9, 0x3a }; + static u8 __is_Jcc(u8 *insn) /* Jcc.d32 */ { u8 ret = 0; @@ -69,7 +74,10 @@ static void __ref __static_call_transform(void *insn, enum insn_type type, emulate = code; code = &xor5rax; } - + if (func == &__WARN_trap) { + emulate = code; + code = &warninsn; + } break; case NOP: @@ -128,7 +136,8 @@ static void __static_call_validate(u8 *insn, bool tail, bool tramp) } else { if (opcode == CALL_INSN_OPCODE || !memcmp(insn, x86_nops[5], 5) || - !memcmp(insn, xor5rax, 5)) + !memcmp(insn, xor5rax, 5) || + !memcmp(insn, warninsn, 5)) return; } diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 6b22611e69cc..cb324cc1fd99 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -31,6 +31,7 @@ #include <linux/kexec.h> #include <linux/sched.h> #include <linux/sched/task_stack.h> +#include <linux/static_call.h> #include <linux/timer.h> #include <linux/init.h> #include <linux/bug.h> @@ -102,25 +103,37 @@ __always_inline int is_valid_bugaddr(unsigned long addr) * UBSan{0}: 67 0f b9 00 ud1 (%eax),%eax * UBSan{10}: 67 0f b9 40 10 ud1 0x10(%eax),%eax * static_call: 0f b9 cc ud1 %esp,%ecx + * __WARN_trap: 67 48 0f b9 3a ud1 (%edx),%reg * - * Notably UBSAN uses EAX, static_call uses ECX. + * Notable, since __WARN_trap can use all registers, the distinction between + * UD1 users is through R/M. */ __always_inline int decode_bug(unsigned long addr, s32 *imm, int *len) { unsigned long start = addr; + u8 v, reg, rm, rex = 0; + int type = BUG_UD1; bool lock = false; - u8 v; if (addr < TASK_SIZE_MAX) return BUG_NONE; - v = *(u8 *)(addr++); - if (v == INSN_ASOP) + for (;;) { v = *(u8 *)(addr++); + if (v == INSN_ASOP) + continue; - if (v == INSN_LOCK) { - lock = true; - v = *(u8 *)(addr++); + if (v == INSN_LOCK) { + lock = true; + continue; + } + + if ((v & 0xf0) == 0x40) { + rex = v; + continue; + } + + break; } switch (v) { @@ -156,18 +169,33 @@ __always_inline int decode_bug(unsigned long addr, s32 *imm, int *len) if (X86_MODRM_MOD(v) != 3 && X86_MODRM_RM(v) == 4) addr++; /* SIB */ + reg = X86_MODRM_REG(v) + 8*!!X86_REX_R(rex); + rm = X86_MODRM_RM(v) + 8*!!X86_REX_B(rex); + /* Decode immediate, if present */ switch (X86_MODRM_MOD(v)) { case 0: if (X86_MODRM_RM(v) == 5) - addr += 4; /* RIP + disp32 */ + addr += 4; /* RIP + disp32 */ + + if (rm == 0) /* (%eax) */ + type = BUG_UD1_UBSAN; + + if (rm == 2) { /* (%edx) */ + *imm = reg; + type = BUG_UD1_WARN; + } break; case 1: *imm = *(s8 *)addr; addr += 1; + if (rm == 0) /* (%eax) */ + type = BUG_UD1_UBSAN; break; case 2: *imm = *(s32 *)addr; addr += 4; + if (rm == 0) /* (%eax) */ + type = BUG_UD1_UBSAN; break; case 3: break; @@ -176,12 +204,76 @@ __always_inline int decode_bug(unsigned long addr, s32 *imm, int *len) /* record instruction length */ *len = addr - start; - if (X86_MODRM_REG(v) == 0) /* EAX */ - return BUG_UD1_UBSAN; + return type; +} - return BUG_UD1; +static inline unsigned long pt_regs_val(struct pt_regs *regs, int nr) +{ + int offset = pt_regs_offset(regs, nr); + if (WARN_ON_ONCE(offset < -0)) + return 0; + return *((unsigned long *)((void *)regs + offset)); } +#ifdef HAVE_ARCH_BUG_FORMAT_ARGS +DEFINE_STATIC_CALL(WARN_trap, __WARN_trap); +EXPORT_STATIC_CALL_TRAMP(WARN_trap); + +/* + * Create a va_list from an exception context. + */ +void *__warn_args(struct arch_va_list *args, struct pt_regs *regs) +{ + /* + * Register save area; populate with function call argument registers + */ + args->regs[0] = regs->di; + args->regs[1] = regs->si; + args->regs[2] = regs->dx; + args->regs[3] = regs->cx; + args->regs[4] = regs->r8; + args->regs[5] = regs->r9; + + /* + * From the ABI document: + * + * @gp_offset - the element holds the offset in bytes from + * reg_save_area to the place where the next available general purpose + * argument register is saved. In case all argument registers have + * been exhausted, it is set to the value 48 (6*8). + * + * @fp_offset - the element holds the offset in bytes from + * reg_save_area to the place where the next available floating point + * argument is saved. In case all argument registers have been + * exhausted, it is set to the value 176 (6*8 + 8*16) + * + * @overflow_arg_area - this pointer is used to fetch arguments passed + * on the stack. It is initialized with the address of the first + * argument passed on the stack, if any, and then always updated to + * point to the start of the next argument on the stack. + * + * @reg_save_area - the element points to the start of the register + * save area. + * + * Notably the vararg starts with the second argument and there are no + * floating point arguments in the kernel. + */ + args->args.gp_offset = 1*8; + args->args.fp_offset = 6*8 + 8*16; + args->args.reg_save_area = &args->regs; + args->args.overflow_arg_area = (void *)regs->sp; + + /* + * If the exception came from __WARN_trap, there is a return + * address on the stack, skip that. This is why any __WARN_trap() + * caller must inhibit tail-call optimization. + */ + if ((void *)regs->ip == &__WARN_trap) + args->args.overflow_arg_area += 8; + + return &args->args; +} +#endif /* HAVE_ARCH_BUG_FORMAT */ static nokprobe_inline int do_trap_no_signal(struct task_struct *tsk, int trapnr, const char *str, @@ -334,6 +426,11 @@ static noinstr bool handle_bug(struct pt_regs *regs) raw_local_irq_enable(); switch (ud_type) { + case BUG_UD1_WARN: + if (report_bug_entry((void *)pt_regs_val(regs, ud_imm), regs) == BUG_TRAP_TYPE_WARN) + handled = true; + break; + case BUG_UD2: if (report_bug(regs->ip, regs) == BUG_TRAP_TYPE_WARN) { handled = true; diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index 387720933973..09e8eccee8ed 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -13,10 +13,19 @@ #define BUGFLAG_ONCE (1 << 1) #define BUGFLAG_DONE (1 << 2) #define BUGFLAG_NO_CUT_HERE (1 << 3) /* CUT_HERE already sent */ +#define BUGFLAG_ARGS (1 << 4) #define BUGFLAG_TAINT(taint) ((taint) << 8) #define BUG_GET_TAINT(bug) ((bug)->flags >> 8) #endif +#ifndef WARN_CONDITION_STR +#ifdef CONFIG_DEBUG_BUGVERBOSE_DETAILED +# define WARN_CONDITION_STR(cond_str) "[" cond_str "] " +#else +# define WARN_CONDITION_STR(cond_str) +#endif +#endif /* WARN_CONDITION_STR */ + #ifndef __ASSEMBLY__ #include <linux/panic.h> #include <linux/printk.h> @@ -29,19 +38,20 @@ void __warn(const char *file, int line, void *caller, unsigned taint, #ifdef CONFIG_BUG -#ifdef CONFIG_GENERIC_BUG -struct bug_entry { #ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS - unsigned long bug_addr; +#define BUG_REL(type, name) type name #else - signed int bug_addr_disp; +#define BUG_REL(type, name) signed int name##_disp #endif -#ifdef CONFIG_DEBUG_BUGVERBOSE -#ifndef CONFIG_GENERIC_BUG_RELATIVE_POINTERS - const char *file; -#else - signed int file_disp; + +#ifdef CONFIG_GENERIC_BUG +struct bug_entry { + BUG_REL(unsigned long, bug_addr); +#ifdef HAVE_ARCH_BUG_FORMAT + BUG_REL(const char *, format); #endif +#ifdef CONFIG_DEBUG_BUGVERBOSE + BUG_REL(const char *, file); unsigned short line; #endif unsigned short flags; @@ -92,28 +102,50 @@ void warn_slowpath_fmt(const char *file, const int line, unsigned taint, const char *fmt, ...); extern __printf(1, 2) void __warn_printk(const char *fmt, ...); -#ifndef __WARN_FLAGS -#define __WARN() __WARN_printf(TAINT_WARN, NULL) +#ifdef __WARN_FLAGS +#define __WARN() __WARN_FLAGS("", BUGFLAG_TAINT(TAINT_WARN)) + +#ifndef WARN_ON +#define WARN_ON(condition) ({ \ + int __ret_warn_on = !!(condition); \ + if (unlikely(__ret_warn_on)) \ + __WARN_FLAGS(#condition, \ + BUGFLAG_TAINT(TAINT_WARN)); \ + unlikely(__ret_warn_on); \ +}) +#endif + +#ifndef WARN_ON_ONCE +#define WARN_ON_ONCE(condition) ({ \ + int __ret_warn_on = !!(condition); \ + if (unlikely(__ret_warn_on)) \ + __WARN_FLAGS(#condition, \ + BUGFLAG_ONCE | \ + BUGFLAG_TAINT(TAINT_WARN)); \ + unlikely(__ret_warn_on); \ +}) +#endif +#endif /* __WARN_FLAGS */ + +#if defined(__WARN_FLAGS) && !defined(__WARN_printf) #define __WARN_printf(taint, arg...) do { \ instrumentation_begin(); \ - warn_slowpath_fmt(__FILE__, __LINE__, taint, arg); \ + __warn_printk(arg); \ + __WARN_FLAGS("", BUGFLAG_NO_CUT_HERE | BUGFLAG_TAINT(taint));\ instrumentation_end(); \ } while (0) -#else -#define __WARN() __WARN_FLAGS(BUGFLAG_TAINT(TAINT_WARN)) +#endif + +#ifndef __WARN_printf #define __WARN_printf(taint, arg...) do { \ instrumentation_begin(); \ - __warn_printk(arg); \ - __WARN_FLAGS(BUGFLAG_NO_CUT_HERE | BUGFLAG_TAINT(taint));\ + warn_slowpath_fmt(__FILE__, __LINE__, taint, arg); \ instrumentation_end(); \ } while (0) -#define WARN_ON_ONCE(condition) ({ \ - int __ret_warn_on = !!(condition); \ - if (unlikely(__ret_warn_on)) \ - __WARN_FLAGS(BUGFLAG_ONCE | \ - BUGFLAG_TAINT(TAINT_WARN)); \ - unlikely(__ret_warn_on); \ -}) +#endif + +#ifndef __WARN +#define __WARN() __WARN_printf(TAINT_WARN, NULL) #endif /* used internally by panic.c */ @@ -148,8 +180,10 @@ extern __printf(1, 2) void __warn_printk(const char *fmt, ...); DO_ONCE_LITE_IF(condition, WARN_ON, 1) #endif +#ifndef WARN_ONCE #define WARN_ONCE(condition, format...) \ DO_ONCE_LITE_IF(condition, WARN, 1, format) +#endif #define WARN_TAINT_ONCE(condition, taint, format...) \ DO_ONCE_LITE_IF(condition, WARN_TAINT, 1, taint, format) diff --git a/include/linux/bug.h b/include/linux/bug.h index a9948a9f1093..17a4933c611b 100644 --- a/include/linux/bug.h +++ b/include/linux/bug.h @@ -42,6 +42,7 @@ void bug_get_file_line(struct bug_entry *bug, const char **file, struct bug_entry *find_bug(unsigned long bugaddr); enum bug_trap_type report_bug(unsigned long bug_addr, struct pt_regs *regs); +enum bug_trap_type report_bug_entry(struct bug_entry *bug, struct pt_regs *regs); /* These are defined by the architecture */ int is_valid_bugaddr(unsigned long addr); @@ -62,6 +63,13 @@ static inline enum bug_trap_type report_bug(unsigned long bug_addr, } struct bug_entry; + +static inline enum bug_trap_type +report_bug_entry(struct bug_entry *bug, struct pt_regs *regs) +{ + return BUG_TRAP_TYPE_BUG; +} + static inline void bug_get_file_line(struct bug_entry *bug, const char **file, unsigned int *line) { diff --git a/kernel/panic.c b/kernel/panic.c index 24cc3eec1805..b2f2470af7e5 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -873,13 +873,15 @@ void __warn(const char *file, int line, void *caller, unsigned taint, disable_trace_on_warning(); - if (file) - pr_warn("WARNING: CPU: %d PID: %d at %s:%d %pS\n", - raw_smp_processor_id(), current->pid, file, line, - caller); - else - pr_warn("WARNING: CPU: %d PID: %d at %pS\n", - raw_smp_processor_id(), current->pid, caller); + if (file) { + pr_warn("WARNING: %s:%d at %pS, CPU#%d: %s/%d\n", + file, line, caller, + raw_smp_processor_id(), current->comm, current->pid); + } else { + pr_warn("WARNING: at %pS, CPU#%d: %s/%d\n", + caller, + raw_smp_processor_id(), current->comm, current->pid); + } #pragma GCC diagnostic push #ifndef __clang__ diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 713cc94caa02..742b23ef0d8b 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -206,6 +206,16 @@ config DEBUG_BUGVERBOSE of the BUG call as well as the EIP and oops trace. This aids debugging but costs about 70-100K of memory. +config DEBUG_BUGVERBOSE_DETAILED + bool "Verbose WARN_ON_ONCE() reporting (adds 100K)" if DEBUG_BUGVERBOSE + help + Say Y here to make WARN_ON_ONCE() output the condition string of the + warning, in addition to the file name and line number. + This helps debugging, but costs about 100K of memory. + + Say N if unsure. + + endmenu # "printk and dmesg options" config DEBUG_KERNEL diff --git a/lib/bug.c b/lib/bug.c index b1f07459c2ee..edd9041f89f3 100644 --- a/lib/bug.c +++ b/lib/bug.c @@ -139,6 +139,29 @@ void bug_get_file_line(struct bug_entry *bug, const char **file, #endif } +static const char *bug_get_format(struct bug_entry *bug) +{ + const char *format = NULL; +#ifdef HAVE_ARCH_BUG_FORMAT +#ifdef CONFIG_GENERIC_BUG_RELATIVE_POINTERS + /* + * Allow an architecture to: + * - relative encode NULL (difficult vs KASLR); + * - use a literal 0 (there are no valid objects inside + * the __bug_table itself to refer to after all); + * - use an empty string. + */ + if (bug->format_disp) + format = (const char *)&bug->format_disp + bug->format_disp; + if (format && format[0] == '\0') + format = NULL; +#else + format = bug->format; +#endif +#endif + return format; +} + struct bug_entry *find_bug(unsigned long bugaddr) { struct bug_entry *bug; @@ -150,26 +173,51 @@ struct bug_entry *find_bug(unsigned long bugaddr) return module_find_bug(bugaddr); } -static enum bug_trap_type __report_bug(unsigned long bugaddr, struct pt_regs *regs) +static void __warn_printf(const char *fmt, struct pt_regs *regs) { - struct bug_entry *bug; - const char *file; - unsigned line, warning, once, done; + if (!fmt) + return; + +#ifdef HAVE_ARCH_BUG_FORMAT_ARGS + if (regs) { + struct arch_va_list _args; + va_list *args = __warn_args(&_args, regs); + + if (args) { + vprintk(fmt, *args); + return; + } + } +#endif + + printk("%s", fmt); +} - if (!is_valid_bugaddr(bugaddr)) - return BUG_TRAP_TYPE_NONE; +static enum bug_trap_type __report_bug(struct bug_entry *bug, unsigned long bugaddr, struct pt_regs *regs) +{ + bool warning, once, done, no_cut, has_args; + const char *file, *fmt; + unsigned line; + + if (!bug) { + if (!is_valid_bugaddr(bugaddr)) + return BUG_TRAP_TYPE_NONE; - bug = find_bug(bugaddr); - if (!bug) - return BUG_TRAP_TYPE_NONE; + bug = find_bug(bugaddr); + if (!bug) + return BUG_TRAP_TYPE_NONE; + } disable_trace_on_warning(); bug_get_file_line(bug, &file, &line); + fmt = bug_get_format(bug); - warning = (bug->flags & BUGFLAG_WARNING) != 0; - once = (bug->flags & BUGFLAG_ONCE) != 0; - done = (bug->flags & BUGFLAG_DONE) != 0; + warning = bug->flags & BUGFLAG_WARNING; + once = bug->flags & BUGFLAG_ONCE; + done = bug->flags & BUGFLAG_DONE; + no_cut = bug->flags & BUGFLAG_NO_CUT_HERE; + has_args = bug->flags & BUGFLAG_ARGS; if (warning && once) { if (done) @@ -187,8 +235,10 @@ static enum bug_trap_type __report_bug(unsigned long bugaddr, struct pt_regs *re * "cut here" line now. WARN() issues its own "cut here" before the * extra debugging message it writes before triggering the handler. */ - if ((bug->flags & BUGFLAG_NO_CUT_HERE) == 0) + if (!no_cut) { printk(KERN_DEFAULT CUT_HERE); + __warn_printf(fmt, has_args ? regs : NULL); + } if (warning) { /* this is a WARN_ON rather than BUG/BUG_ON */ @@ -206,13 +256,25 @@ static enum bug_trap_type __report_bug(unsigned long bugaddr, struct pt_regs *re return BUG_TRAP_TYPE_BUG; } +enum bug_trap_type report_bug_entry(struct bug_entry *bug, struct pt_regs *regs) +{ + enum bug_trap_type ret; + bool rcu = false; + + rcu = warn_rcu_enter(); + ret = __report_bug(bug, 0, regs); + warn_rcu_exit(rcu); + + return ret; +} + enum bug_trap_type report_bug(unsigned long bugaddr, struct pt_regs *regs) { enum bug_trap_type ret; bool rcu = false; rcu = warn_rcu_enter(); - ret = __report_bug(bugaddr, regs); + ret = __report_bug(NULL, bugaddr, regs); warn_rcu_exit(rcu); return ret; |