| 1 | //
|
|---|
| 2 | // Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
|
|---|
| 3 | //
|
|---|
| 4 | // The contents of this file are covered under the licence agreement in the
|
|---|
| 5 | // file "LICENCE" distributed with Cforall.
|
|---|
| 6 | //
|
|---|
| 7 | // interpose.c --
|
|---|
| 8 | //
|
|---|
| 9 | // Author : Thierry Delisle
|
|---|
| 10 | // Created On : Wed Mar 29 16:10:31 2017
|
|---|
| 11 | // Last Modified By : Peter A. Buhr
|
|---|
| 12 | // Last Modified On : Sat Feb 8 08:40:34 2020
|
|---|
| 13 | // Update Count : 163
|
|---|
| 14 | //
|
|---|
| 15 |
|
|---|
| 16 | #include <stdarg.h> // va_start, va_end
|
|---|
| 17 | #include <string.h> // strlen
|
|---|
| 18 | #include <unistd.h> // _exit, getpid
|
|---|
| 19 | #define __USE_GNU
|
|---|
| 20 | #include <signal.h>
|
|---|
| 21 | #undef __USE_GNU
|
|---|
| 22 | extern "C" {
|
|---|
| 23 | #include <dlfcn.h> // dlopen, dlsym
|
|---|
| 24 | #include <execinfo.h> // backtrace, messages
|
|---|
| 25 | }
|
|---|
| 26 |
|
|---|
| 27 | #include "bits/debug.hfa"
|
|---|
| 28 | #include "bits/defs.hfa"
|
|---|
| 29 | #include "bits/signal.hfa" // sigHandler_?
|
|---|
| 30 | #include "startup.hfa" // STARTUP_PRIORITY_CORE
|
|---|
| 31 | #include <assert.h>
|
|---|
| 32 |
|
|---|
| 33 | //=============================================================================================
|
|---|
| 34 | // Interposing helpers
|
|---|
| 35 | //=============================================================================================
|
|---|
| 36 |
|
|---|
| 37 | void preload_libgcc(void) {
|
|---|
| 38 | dlopen( "libgcc_s.so.1", RTLD_NOW );
|
|---|
| 39 | if ( const char * error = dlerror() ) abort( "interpose_symbol : internal error pre-loading libgcc, %s\n", error );
|
|---|
| 40 | }
|
|---|
| 41 |
|
|---|
| 42 | typedef void (* generic_fptr_t)(void);
|
|---|
| 43 | generic_fptr_t interpose_symbol( const char symbol[], const char version[] ) {
|
|---|
| 44 | const char * error;
|
|---|
| 45 |
|
|---|
| 46 | static void * library;
|
|---|
| 47 | if ( ! library ) {
|
|---|
| 48 | #if defined( RTLD_NEXT )
|
|---|
| 49 | library = RTLD_NEXT;
|
|---|
| 50 | #else
|
|---|
| 51 | // missing RTLD_NEXT => must hard-code library name, assuming libstdc++
|
|---|
| 52 | library = dlopen( "libc.so.6", RTLD_LAZY );
|
|---|
| 53 | error = dlerror();
|
|---|
| 54 | if ( error ) {
|
|---|
| 55 | abort( "interpose_symbol : failed to open libc, %s\n", error );
|
|---|
| 56 | }
|
|---|
| 57 | #endif
|
|---|
| 58 | } // if
|
|---|
| 59 |
|
|---|
| 60 | union { generic_fptr_t fptr; void * ptr; } originalFunc;
|
|---|
| 61 |
|
|---|
| 62 | #if defined( _GNU_SOURCE )
|
|---|
| 63 | if ( version ) {
|
|---|
| 64 | originalFunc.ptr = dlvsym( library, symbol, version );
|
|---|
| 65 | } else {
|
|---|
| 66 | originalFunc.ptr = dlsym( library, symbol );
|
|---|
| 67 | }
|
|---|
| 68 | #else
|
|---|
| 69 | originalFunc.ptr = dlsym( library, symbol );
|
|---|
| 70 | #endif // _GNU_SOURCE
|
|---|
| 71 |
|
|---|
| 72 | error = dlerror();
|
|---|
| 73 | if ( error ) abort( "interpose_symbol : internal error, %s\n", error );
|
|---|
| 74 |
|
|---|
| 75 | return originalFunc.fptr;
|
|---|
| 76 | }
|
|---|
| 77 |
|
|---|
| 78 | #define INTERPOSE_LIBC( x, ver ) __cabi_libc.x = (typeof(__cabi_libc.x))interpose_symbol( #x, ver )
|
|---|
| 79 |
|
|---|
| 80 | //=============================================================================================
|
|---|
| 81 | // Interposition Startup logic
|
|---|
| 82 | //=============================================================================================
|
|---|
| 83 |
|
|---|
| 84 | void sigHandler_segv( __CFA_SIGPARMS__ );
|
|---|
| 85 | void sigHandler_ill ( __CFA_SIGPARMS__ );
|
|---|
| 86 | void sigHandler_fpe ( __CFA_SIGPARMS__ );
|
|---|
| 87 | void sigHandler_abrt( __CFA_SIGPARMS__ );
|
|---|
| 88 | void sigHandler_term( __CFA_SIGPARMS__ );
|
|---|
| 89 |
|
|---|
| 90 | struct {
|
|---|
| 91 | void (* exit)( int ) __attribute__(( __noreturn__ ));
|
|---|
| 92 | void (* abort)( void ) __attribute__(( __noreturn__ ));
|
|---|
| 93 | } __cabi_libc;
|
|---|
| 94 |
|
|---|
| 95 | extern "C" {
|
|---|
| 96 | void __cfaabi_interpose_startup(void) __attribute__(( constructor( STARTUP_PRIORITY_CORE ) ));
|
|---|
| 97 | void __cfaabi_interpose_startup( void ) {
|
|---|
| 98 | const char *version = 0p;
|
|---|
| 99 |
|
|---|
| 100 | preload_libgcc();
|
|---|
| 101 |
|
|---|
| 102 | #pragma GCC diagnostic push
|
|---|
| 103 | #pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
|
|---|
| 104 | INTERPOSE_LIBC( abort, version );
|
|---|
| 105 | INTERPOSE_LIBC( exit , version );
|
|---|
| 106 | #pragma GCC diagnostic pop
|
|---|
| 107 |
|
|---|
| 108 | // As a precaution (and necessity), errors that result in termination are delivered on a separate stack because
|
|---|
| 109 | // task stacks might be very small (4K) and the signal delivery corrupts memory to the point that a clean
|
|---|
| 110 | // shutdown is impossible. Also, when a stack overflow encounters the non-accessible sentinel page (debug only)
|
|---|
| 111 | // and generates a segment fault, the signal cannot be delivered on the sentinel page. Finally, calls to abort
|
|---|
| 112 | // print a stack trace that uses substantial stack space.
|
|---|
| 113 |
|
|---|
| 114 | #define MINSTKSZ SIGSTKSZ * 8
|
|---|
| 115 | static char stack[MINSTKSZ] __attribute__(( aligned (16) ));
|
|---|
| 116 | static stack_t ss;
|
|---|
| 117 |
|
|---|
| 118 | ss.ss_sp = stack;
|
|---|
| 119 | ss.ss_size = MINSTKSZ;
|
|---|
| 120 | ss.ss_flags = 0;
|
|---|
| 121 | if ( sigaltstack( &ss, 0p ) == -1 ) {
|
|---|
| 122 | abort( "__cfaabi_interpose_startup : internal error, sigaltstack error(%d) %s.", errno, strerror( errno ) );
|
|---|
| 123 | } // if
|
|---|
| 124 |
|
|---|
| 125 | // Failure handler
|
|---|
| 126 | __cfaabi_sigaction( SIGSEGV, sigHandler_segv, SA_SIGINFO | SA_ONSTACK );
|
|---|
| 127 | __cfaabi_sigaction( SIGBUS , sigHandler_segv, SA_SIGINFO | SA_ONSTACK );
|
|---|
| 128 | __cfaabi_sigaction( SIGILL , sigHandler_ill , SA_SIGINFO | SA_ONSTACK );
|
|---|
| 129 | __cfaabi_sigaction( SIGFPE , sigHandler_fpe , SA_SIGINFO | SA_ONSTACK );
|
|---|
| 130 | __cfaabi_sigaction( SIGTERM, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // one shot handler, return to default
|
|---|
| 131 | __cfaabi_sigaction( SIGINT , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND );
|
|---|
| 132 | __cfaabi_sigaction( SIGABRT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND );
|
|---|
| 133 | __cfaabi_sigaction( SIGHUP , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // terminal hangup
|
|---|
| 134 | }
|
|---|
| 135 | }
|
|---|
| 136 |
|
|---|
| 137 | //=============================================================================================
|
|---|
| 138 | // Terminating Signals logic
|
|---|
| 139 | //=============================================================================================
|
|---|
| 140 |
|
|---|
| 141 | // Forward declare abort after the __typeof__ call to avoid ambiguities
|
|---|
| 142 | void exit( int status, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ ));
|
|---|
| 143 | void abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ ));
|
|---|
| 144 | void abort( bool signalAbort, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ ));
|
|---|
| 145 |
|
|---|
| 146 | extern "C" {
|
|---|
| 147 | void abort( void ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) {
|
|---|
| 148 | abort( false, "%s", "" );
|
|---|
| 149 | }
|
|---|
| 150 |
|
|---|
| 151 | void __cabi_abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ )) {
|
|---|
| 152 | va_list argp;
|
|---|
| 153 | va_start( argp, fmt );
|
|---|
| 154 | abort( false, fmt, argp );
|
|---|
| 155 | va_end( argp );
|
|---|
| 156 | }
|
|---|
| 157 |
|
|---|
| 158 | void exit( int status ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) {
|
|---|
| 159 | __cabi_libc.exit( status );
|
|---|
| 160 | }
|
|---|
| 161 | }
|
|---|
| 162 |
|
|---|
| 163 | void * kernel_abort( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 0p; }
|
|---|
| 164 | void kernel_abort_msg( void * data, char buffer[], int size ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {}
|
|---|
| 165 | // See concurrency/kernel.cfa for strong definition used in multi-processor mode.
|
|---|
| 166 | int kernel_abort_lastframe( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 4; }
|
|---|
| 167 |
|
|---|
| 168 | enum { abort_text_size = 1024 };
|
|---|
| 169 | static char abort_text[ abort_text_size ];
|
|---|
| 170 |
|
|---|
| 171 | static void __cfaabi_backtrace( int start ) {
|
|---|
| 172 | enum { Frames = 50, }; // maximum number of stack frames
|
|---|
| 173 | int last = kernel_abort_lastframe(); // skip last N stack frames
|
|---|
| 174 |
|
|---|
| 175 | void * array[Frames];
|
|---|
| 176 | size_t size = backtrace( array, Frames );
|
|---|
| 177 | char ** messages = backtrace_symbols( array, size ); // does not demangle names
|
|---|
| 178 |
|
|---|
| 179 | *index( messages[0], '(' ) = '\0'; // find executable name
|
|---|
| 180 | __cfaabi_bits_print_nolock( STDERR_FILENO, "Stack back trace for: %s\n", messages[0]);
|
|---|
| 181 |
|
|---|
| 182 | for ( unsigned int i = start; i < size - last && messages != 0p; i += 1 ) {
|
|---|
| 183 | char * name = 0p, * offset_begin = 0p, * offset_end = 0p;
|
|---|
| 184 |
|
|---|
| 185 | for ( char * p = messages[i]; *p; p += 1 ) { // find parantheses and +offset
|
|---|
| 186 | //__cfaabi_bits_print_nolock( "X %s\n", p);
|
|---|
| 187 | if ( *p == '(' ) {
|
|---|
| 188 | name = p;
|
|---|
| 189 | } else if ( *p == '+' ) {
|
|---|
| 190 | offset_begin = p;
|
|---|
| 191 | } else if ( *p == ')' ) {
|
|---|
| 192 | offset_end = p;
|
|---|
| 193 | break;
|
|---|
| 194 | }
|
|---|
| 195 | }
|
|---|
| 196 |
|
|---|
| 197 | // if line contains symbol, print it
|
|---|
| 198 | int frameNo = i - start;
|
|---|
| 199 | if ( name && offset_begin && offset_end && name < offset_begin ) {
|
|---|
| 200 | *name++ = '\0'; // delimit strings
|
|---|
| 201 | *offset_begin++ = '\0';
|
|---|
| 202 | *offset_end++ = '\0';
|
|---|
| 203 |
|
|---|
| 204 | __cfaabi_bits_print_nolock( STDERR_FILENO, "(%i) %s : %s + %s %s\n", frameNo, messages[i], name, offset_begin, offset_end);
|
|---|
| 205 | } else { // otherwise, print the whole line
|
|---|
| 206 | __cfaabi_bits_print_nolock( STDERR_FILENO, "(%i) %s\n", frameNo, messages[i] );
|
|---|
| 207 | }
|
|---|
| 208 | }
|
|---|
| 209 | free( messages );
|
|---|
| 210 | }
|
|---|
| 211 |
|
|---|
| 212 | void exit( int status, const char fmt[], ... ) {
|
|---|
| 213 | va_list args;
|
|---|
| 214 | va_start( args, fmt );
|
|---|
| 215 | vfprintf( stderr, fmt, args );
|
|---|
| 216 | va_end( args );
|
|---|
| 217 | __cabi_libc.exit( status );
|
|---|
| 218 | }
|
|---|
| 219 |
|
|---|
| 220 | void abort( bool signalAbort, const char fmt[], ... ) {
|
|---|
| 221 | void * kernel_data = kernel_abort(); // must be done here to lock down kernel
|
|---|
| 222 | int len;
|
|---|
| 223 |
|
|---|
| 224 | signal( SIGABRT, SIG_DFL ); // prevent final "real" abort from recursing to handler
|
|---|
| 225 |
|
|---|
| 226 | len = snprintf( abort_text, abort_text_size, "Cforall Runtime error (UNIX pid:%ld) ", (long int)getpid() ); // use UNIX pid (versus getPid)
|
|---|
| 227 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
|
|---|
| 228 |
|
|---|
| 229 | assert( fmt );
|
|---|
| 230 | va_list args;
|
|---|
| 231 | va_start( args, fmt );
|
|---|
| 232 |
|
|---|
| 233 | len = vsnprintf( abort_text, abort_text_size, fmt, args );
|
|---|
| 234 | va_end( args );
|
|---|
| 235 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len );
|
|---|
| 236 |
|
|---|
| 237 | if ( fmt[strlen( fmt ) - 1] != '\n' ) { // add optional newline if missing at the end of the format text
|
|---|
| 238 | __cfaabi_dbg_write( "\n", 1 );
|
|---|
| 239 | }
|
|---|
| 240 |
|
|---|
| 241 | kernel_abort_msg( kernel_data, abort_text, abort_text_size );
|
|---|
| 242 | __cfaabi_backtrace( signalAbort ? 4 : 3 );
|
|---|
| 243 |
|
|---|
| 244 | __cabi_libc.abort(); // print stack trace in handler
|
|---|
| 245 | }
|
|---|
| 246 |
|
|---|
| 247 | void abort( const char fmt[], ... ) {
|
|---|
| 248 | va_list args;
|
|---|
| 249 | va_start( args, fmt );
|
|---|
| 250 | abort( false, fmt, args );
|
|---|
| 251 | va_end( args );
|
|---|
| 252 | }
|
|---|
| 253 |
|
|---|
| 254 | void sigHandler_segv( __CFA_SIGPARMS__ ) {
|
|---|
| 255 | if ( sfp->si_addr == 0p ) {
|
|---|
| 256 | abort( true, "Null pointer (0p) dereference.\n" );
|
|---|
| 257 | } else {
|
|---|
| 258 | abort( true, "%s at memory location %p.\n"
|
|---|
| 259 | "Possible cause is reading outside the address space or writing to a protected area within the address space with an invalid pointer or subscript.\n",
|
|---|
| 260 | (sig == SIGSEGV ? "Segment fault" : "Bus error"), sfp->si_addr );
|
|---|
| 261 | }
|
|---|
| 262 | }
|
|---|
| 263 |
|
|---|
| 264 | void sigHandler_ill( __CFA_SIGPARMS__ ) {
|
|---|
| 265 | abort( true, "Executing illegal instruction at location %p.\n"
|
|---|
| 266 | "Possible cause is stack corruption.\n",
|
|---|
| 267 | sfp->si_addr );
|
|---|
| 268 | }
|
|---|
| 269 |
|
|---|
| 270 | void sigHandler_fpe( __CFA_SIGPARMS__ ) {
|
|---|
| 271 | const char * msg;
|
|---|
| 272 |
|
|---|
| 273 | choose( sfp->si_code ) {
|
|---|
| 274 | case FPE_INTDIV, FPE_FLTDIV: msg = "divide by zero";
|
|---|
| 275 | case FPE_FLTOVF: msg = "overflow";
|
|---|
| 276 | case FPE_FLTUND: msg = "underflow";
|
|---|
| 277 | case FPE_FLTRES: msg = "inexact result";
|
|---|
| 278 | case FPE_FLTINV: msg = "invalid operation";
|
|---|
| 279 | default: msg = "unknown";
|
|---|
| 280 | } // choose
|
|---|
| 281 | abort( true, "Computation error %s at location %p.\n", msg, sfp->si_addr );
|
|---|
| 282 | }
|
|---|
| 283 |
|
|---|
| 284 | void sigHandler_term( __CFA_SIGPARMS__ ) {
|
|---|
| 285 | abort( true, "Application interrupted by signal: %s.\n", strsignal( sig ) );
|
|---|
| 286 | }
|
|---|
| 287 |
|
|---|
| 288 | // Local Variables: //
|
|---|
| 289 | // mode: c //
|
|---|
| 290 | // tab-width: 4 //
|
|---|
| 291 | // End: //
|
|---|
