[9d944b2] | 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 |
---|
[6b0b624] | 11 | // Last Modified By : Peter A. Buhr |
---|
[8bb46d2] | 12 | // Last Modified On : Thu Mar 2 13:56:26 2023 |
---|
| 13 | // Update Count : 191 |
---|
[9d944b2] | 14 | // |
---|
| 15 | |
---|
[7867eb9] | 16 | #include <stdarg.h> // va_start, va_end |
---|
[851fd92] | 17 | #include <stdio.h> |
---|
[7867eb9] | 18 | #include <string.h> // strlen |
---|
| 19 | #include <unistd.h> // _exit, getpid |
---|
[58b6d1b] | 20 | #include <signal.h> |
---|
[67db067] | 21 | extern "C" { |
---|
[7867eb9] | 22 | #include <dlfcn.h> // dlopen, dlsym |
---|
| 23 | #include <execinfo.h> // backtrace, messages |
---|
[9d944b2] | 24 | } |
---|
| 25 | |
---|
[73abe95] | 26 | #include "bits/debug.hfa" |
---|
| 27 | #include "bits/defs.hfa" |
---|
| 28 | #include "bits/signal.hfa" // sigHandler_? |
---|
| 29 | #include "startup.hfa" // STARTUP_PRIORITY_CORE |
---|
[1d94116] | 30 | #include <assert.h> |
---|
[9d944b2] | 31 | |
---|
[3d5f2ef1] | 32 | //============================================================================================= |
---|
| 33 | // Interposing helpers |
---|
| 34 | //============================================================================================= |
---|
| 35 | |
---|
[032234bd] | 36 | static void preload_libgcc(void) { |
---|
[ad64520] | 37 | dlopen( "libgcc_s.so.1", RTLD_NOW ); |
---|
| 38 | if ( const char * error = dlerror() ) abort( "interpose_symbol : internal error pre-loading libgcc, %s\n", error ); |
---|
| 39 | } |
---|
| 40 | |
---|
[67db067] | 41 | typedef void (* generic_fptr_t)(void); |
---|
[95dab9e] | 42 | static generic_fptr_t do_interpose_symbol( void * library, const char symbol[], const char version[] ) { |
---|
| 43 | const char * error; |
---|
| 44 | |
---|
| 45 | union { generic_fptr_t fptr; void * ptr; } originalFunc; |
---|
| 46 | |
---|
[c910709] | 47 | originalFunc.ptr = dlsym( library, symbol ); |
---|
[95dab9e] | 48 | error = dlerror(); |
---|
| 49 | if ( error ) abort( "interpose_symbol : internal error, %s\n", error ); |
---|
| 50 | |
---|
| 51 | return originalFunc.fptr; |
---|
| 52 | } |
---|
| 53 | |
---|
[032234bd] | 54 | static generic_fptr_t interpose_symbol( const char symbol[], const char version[] ) { |
---|
[8bb46d2] | 55 | void * library; |
---|
| 56 | #if defined( RTLD_NEXT ) |
---|
| 57 | library = RTLD_NEXT; |
---|
| 58 | #else |
---|
| 59 | library = dlopen( "libc.so.6", RTLD_LAZY ); |
---|
[9d944b2] | 60 | if ( ! library ) { |
---|
[c910709] | 61 | const char * error = dlerror(); |
---|
| 62 | if ( error ) { |
---|
| 63 | abort( "interpose_symbol : failed to open libc, %s\n", error ); |
---|
| 64 | } // if |
---|
[9d944b2] | 65 | } // if |
---|
[8bb46d2] | 66 | #endif |
---|
[9d944b2] | 67 | |
---|
[95dab9e] | 68 | return do_interpose_symbol(library, symbol, version); |
---|
[9d944b2] | 69 | } |
---|
| 70 | |
---|
[67db067] | 71 | #define INTERPOSE_LIBC( x, ver ) __cabi_libc.x = (typeof(__cabi_libc.x))interpose_symbol( #x, ver ) |
---|
[3d5f2ef1] | 72 | |
---|
| 73 | //============================================================================================= |
---|
[67db067] | 74 | // Interposition Startup logic |
---|
[3d5f2ef1] | 75 | //============================================================================================= |
---|
[9d944b2] | 76 | |
---|
[032234bd] | 77 | static void sigHandler_segv( __CFA_SIGPARMS__ ); |
---|
| 78 | static void sigHandler_ill ( __CFA_SIGPARMS__ ); |
---|
| 79 | static void sigHandler_fpe ( __CFA_SIGPARMS__ ); |
---|
| 80 | static void sigHandler_abrt( __CFA_SIGPARMS__ ); |
---|
| 81 | static void sigHandler_term( __CFA_SIGPARMS__ ); |
---|
[dbe9b08] | 82 | |
---|
[032234bd] | 83 | static struct { |
---|
[d7312ac] | 84 | void (* exit)( int ) __attribute__(( __noreturn__ )); |
---|
| 85 | void (* abort)( void ) __attribute__(( __noreturn__ )); |
---|
[3d5f2ef1] | 86 | } __cabi_libc; |
---|
| 87 | |
---|
[032234bd] | 88 | libcfa_public int cfa_main_returned; |
---|
[7dd98b6] | 89 | |
---|
[6bfe5cc] | 90 | extern "C" { |
---|
[95dab9e] | 91 | void __cfathreadabi_interpose_startup( generic_fptr_t (*do_interpose_symbol)( void * library, const char symbol[], const char version[] ) ) __attribute__((weak)); |
---|
[6bfe5cc] | 92 | void __cfaabi_interpose_startup( void ) { |
---|
[8a13c47] | 93 | const char *version = 0p; |
---|
[7dd98b6] | 94 | cfa_main_returned = 0; |
---|
[9d944b2] | 95 | |
---|
[ad64520] | 96 | preload_libgcc(); |
---|
| 97 | |
---|
[43f29f6] | 98 | #pragma GCC diagnostic push |
---|
| 99 | #pragma GCC diagnostic ignored "-Wdiscarded-qualifiers" |
---|
[3d5f2ef1] | 100 | INTERPOSE_LIBC( abort, version ); |
---|
| 101 | INTERPOSE_LIBC( exit , version ); |
---|
[43f29f6] | 102 | #pragma GCC diagnostic pop |
---|
[dbe9b08] | 103 | |
---|
[95dab9e] | 104 | if(__cfathreadabi_interpose_startup) __cfathreadabi_interpose_startup( do_interpose_symbol ); |
---|
| 105 | |
---|
[8bb46d2] | 106 | // SKULLDUGGERY: In Ubuntu 22.04, someone augmented signal.h to allow SIGSTKSZ to be "sysconf(_SC_SIGSTKSZ)" in |
---|
| 107 | // sigstksz.h, as well as 8192 in sigstack.h. HOWEVER, they forgot to provide a mechanism to tell signal.h to |
---|
| 108 | // use sigstack.h rather than sigstksz.h. (I'm not happy.) By undefining _GNU_SOURCE before signal.h and |
---|
| 109 | // redefining it afterwards, you can get 8192, but then nothing works correctly inside of signal.h without |
---|
| 110 | // _GNU_SOURCE defined. So what is needed is a way to get signal.h to use sigstack.h WITH _GNU_SOURCE defined. |
---|
| 111 | // Basically something is wrong with features.h and its use in signal.h. |
---|
| 112 | |
---|
| 113 | #undef SIGSTKSZ |
---|
| 114 | #define SIGSTKSZ 8192 |
---|
| 115 | |
---|
[8a13c47] | 116 | // As a precaution (and necessity), errors that result in termination are delivered on a separate stack because |
---|
| 117 | // task stacks might be very small (4K) and the signal delivery corrupts memory to the point that a clean |
---|
| 118 | // shutdown is impossible. Also, when a stack overflow encounters the non-accessible sentinel page (debug only) |
---|
| 119 | // and generates a segment fault, the signal cannot be delivered on the sentinel page. Finally, calls to abort |
---|
| 120 | // print a stack trace that uses substantial stack space. |
---|
| 121 | |
---|
| 122 | #define MINSTKSZ SIGSTKSZ * 8 |
---|
| 123 | static char stack[MINSTKSZ] __attribute__(( aligned (16) )); |
---|
| 124 | static stack_t ss; |
---|
| 125 | |
---|
| 126 | ss.ss_sp = stack; |
---|
| 127 | ss.ss_size = MINSTKSZ; |
---|
| 128 | ss.ss_flags = 0; |
---|
| 129 | if ( sigaltstack( &ss, 0p ) == -1 ) { |
---|
| 130 | abort( "__cfaabi_interpose_startup : internal error, sigaltstack error(%d) %s.", errno, strerror( errno ) ); |
---|
| 131 | } // if |
---|
| 132 | |
---|
[de94a60] | 133 | // Failure handler |
---|
[92bfda0] | 134 | // internal errors |
---|
| 135 | __cfaabi_sigaction( SIGSEGV, sigHandler_segv, SA_SIGINFO | SA_ONSTACK ); // Invalid memory reference (default: Core) |
---|
| 136 | __cfaabi_sigaction( SIGBUS , sigHandler_segv, SA_SIGINFO | SA_ONSTACK ); // Bus error, bad memory access (default: Core) |
---|
| 137 | __cfaabi_sigaction( SIGILL , sigHandler_ill , SA_SIGINFO | SA_ONSTACK ); // Illegal Instruction (default: Core) |
---|
| 138 | __cfaabi_sigaction( SIGFPE , sigHandler_fpe , SA_SIGINFO | SA_ONSTACK ); // Floating-point exception (default: Core) |
---|
| 139 | |
---|
| 140 | // handlers to outside errors |
---|
| 141 | // reset in-case they insist and send it over and over |
---|
| 142 | __cfaabi_sigaction( SIGTERM, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Termination signal (default: Term) |
---|
| 143 | __cfaabi_sigaction( SIGINT , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Interrupt from keyboard (default: Term) |
---|
| 144 | __cfaabi_sigaction( SIGHUP , sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Hangup detected on controlling terminal or death of controlling process (default: Term) |
---|
| 145 | __cfaabi_sigaction( SIGQUIT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Quit from keyboard (default: Core) |
---|
| 146 | __cfaabi_sigaction( SIGABRT, sigHandler_term, SA_SIGINFO | SA_ONSTACK | SA_RESETHAND ); // Abort signal from abort(3) (default: Core) |
---|
[6bfe5cc] | 147 | } |
---|
[9d944b2] | 148 | } |
---|
| 149 | |
---|
[dbe9b08] | 150 | //============================================================================================= |
---|
| 151 | // Terminating Signals logic |
---|
| 152 | //============================================================================================= |
---|
| 153 | |
---|
[3d5f2ef1] | 154 | // Forward declare abort after the __typeof__ call to avoid ambiguities |
---|
[032234bd] | 155 | libcfa_public void exit( int status, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ )); |
---|
| 156 | libcfa_public void abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ )); |
---|
| 157 | libcfa_public void abort( bool signalAbort, const char fmt[], ... ) __attribute__(( format(printf, 2, 3), __nothrow__, __leaf__, __noreturn__ )); |
---|
| 158 | libcfa_public void __abort( bool signalAbort, const char fmt[], va_list args ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )); |
---|
[3d5f2ef1] | 159 | |
---|
[9d944b2] | 160 | extern "C" { |
---|
[032234bd] | 161 | libcfa_public void abort( void ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) { |
---|
[1d94116] | 162 | abort( false, "%s", "" ); |
---|
[9d944b2] | 163 | } |
---|
| 164 | |
---|
[032234bd] | 165 | libcfa_public void __cabi_abort( const char fmt[], ... ) __attribute__(( format(printf, 1, 2), __nothrow__, __leaf__, __noreturn__ )) { |
---|
[3d5f2ef1] | 166 | va_list argp; |
---|
| 167 | va_start( argp, fmt ); |
---|
[d870df3] | 168 | __abort( false, fmt, argp ); |
---|
[3d5f2ef1] | 169 | va_end( argp ); |
---|
[9d944b2] | 170 | } |
---|
| 171 | |
---|
[032234bd] | 172 | libcfa_public void exit( int status ) __attribute__(( __nothrow__, __leaf__, __noreturn__ )) { |
---|
[169d944] | 173 | __cabi_libc.exit( status ); |
---|
[3d5f2ef1] | 174 | } |
---|
[9d944b2] | 175 | } |
---|
| 176 | |
---|
[92bfda0] | 177 | // See concurrency/kernel.cfa and concurrency/preemption.cfa for strong definition used in multi-processor mode. |
---|
| 178 | void __kernel_abort_lock( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {} |
---|
| 179 | void __kernel_abort_msg( char buffer[], int size ) __attribute__(( __nothrow__, __leaf__, __weak__ )) {} |
---|
| 180 | int __kernel_abort_lastframe( void ) __attribute__(( __nothrow__, __leaf__, __weak__ )) { return 4; } |
---|
[9d944b2] | 181 | |
---|
| 182 | enum { abort_text_size = 1024 }; |
---|
| 183 | static char abort_text[ abort_text_size ]; |
---|
| 184 | |
---|
[8a13c47] | 185 | static void __cfaabi_backtrace( int start ) { |
---|
[74330e7] | 186 | enum { Frames = 50, }; // maximum number of stack frames |
---|
[92bfda0] | 187 | int last = __kernel_abort_lastframe(); // skip last N stack frames |
---|
[dbe9b08] | 188 | |
---|
| 189 | void * array[Frames]; |
---|
[6bfe5cc] | 190 | size_t size = backtrace( array, Frames ); |
---|
[74330e7] | 191 | char ** messages = backtrace_symbols( array, size ); // does not demangle names |
---|
[dbe9b08] | 192 | |
---|
[8a13c47] | 193 | *index( messages[0], '(' ) = '\0'; // find executable name |
---|
[1c40091] | 194 | __cfaabi_bits_print_nolock( STDERR_FILENO, "Stack back trace for: %s\n", messages[0]); |
---|
[dbe9b08] | 195 | |
---|
[8a13c47] | 196 | for ( unsigned int i = start; i < size - last && messages != 0p; i += 1 ) { |
---|
[524627e] | 197 | char * name = 0p, * offset_begin = 0p, * offset_end = 0p; |
---|
[dbe9b08] | 198 | |
---|
[74330e7] | 199 | for ( char * p = messages[i]; *p; p += 1 ) { // find parantheses and +offset |
---|
[1c40091] | 200 | //__cfaabi_bits_print_nolock( "X %s\n", p); |
---|
[dbe9b08] | 201 | if ( *p == '(' ) { |
---|
| 202 | name = p; |
---|
[4f37255] | 203 | } else if ( *p == '+' ) { |
---|
[dbe9b08] | 204 | offset_begin = p; |
---|
[4f37255] | 205 | } else if ( *p == ')' ) { |
---|
[dbe9b08] | 206 | offset_end = p; |
---|
| 207 | break; |
---|
| 208 | } |
---|
| 209 | } |
---|
| 210 | |
---|
[8a13c47] | 211 | // if line contains symbol, print it |
---|
| 212 | int frameNo = i - start; |
---|
[dbe9b08] | 213 | if ( name && offset_begin && offset_end && name < offset_begin ) { |
---|
[8a13c47] | 214 | *name++ = '\0'; // delimit strings |
---|
[dbe9b08] | 215 | *offset_begin++ = '\0'; |
---|
| 216 | *offset_end++ = '\0'; |
---|
| 217 | |
---|
[1c40091] | 218 | __cfaabi_bits_print_nolock( STDERR_FILENO, "(%i) %s : %s + %s %s\n", frameNo, messages[i], name, offset_begin, offset_end); |
---|
[4f37255] | 219 | } else { // otherwise, print the whole line |
---|
[1c40091] | 220 | __cfaabi_bits_print_nolock( STDERR_FILENO, "(%i) %s\n", frameNo, messages[i] ); |
---|
[dbe9b08] | 221 | } |
---|
| 222 | } |
---|
| 223 | free( messages ); |
---|
| 224 | } |
---|
| 225 | |
---|
[8a13c47] | 226 | void exit( int status, const char fmt[], ... ) { |
---|
| 227 | va_list args; |
---|
| 228 | va_start( args, fmt ); |
---|
| 229 | vfprintf( stderr, fmt, args ); |
---|
| 230 | va_end( args ); |
---|
| 231 | __cabi_libc.exit( status ); |
---|
| 232 | } |
---|
| 233 | |
---|
[92bfda0] | 234 | static volatile bool __abort_first = 0; |
---|
[6011658] | 235 | |
---|
[d870df3] | 236 | // Cannot forward va_list. |
---|
| 237 | void __abort( bool signalAbort, const char fmt[], va_list args ) { |
---|
[92bfda0] | 238 | // Multiple threads can come here from multiple paths |
---|
| 239 | // To make sure this is safe any concurrent/subsequent call to abort is redirected to libc-abort |
---|
| 240 | bool first = ! __atomic_test_and_set( &__abort_first, __ATOMIC_SEQ_CST); |
---|
[8a13c47] | 241 | |
---|
[92bfda0] | 242 | // Prevent preemption from kicking-in and messing with the abort |
---|
| 243 | __kernel_abort_lock(); |
---|
[8a13c47] | 244 | |
---|
[92bfda0] | 245 | // first to abort ? |
---|
| 246 | if ( !first ) { |
---|
| 247 | // We aren't the first to abort just let C handle it |
---|
| 248 | signal( SIGABRT, SIG_DFL ); // restore default in case we came here through the function. |
---|
| 249 | __cabi_libc.abort(); |
---|
| 250 | } |
---|
[8a13c47] | 251 | |
---|
[92bfda0] | 252 | int len = snprintf( abort_text, abort_text_size, "Cforall Runtime error (UNIX pid:%ld) ", (long int)getpid() ); // use UNIX pid (versus getPid) |
---|
| 253 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
---|
[8a13c47] | 254 | |
---|
[92bfda0] | 255 | // print the cause of the error |
---|
| 256 | assert( fmt ); |
---|
| 257 | len = vsnprintf( abort_text, abort_text_size, fmt, args ); |
---|
| 258 | __cfaabi_bits_write( STDERR_FILENO, abort_text, len ); |
---|
[6011658] | 259 | |
---|
[92bfda0] | 260 | // add optional newline if missing at the end of the format text |
---|
| 261 | if ( fmt[strlen( fmt ) - 1] != '\n' ) { |
---|
| 262 | __cfaabi_bits_write( STDERR_FILENO, "\n", 1 ); |
---|
| 263 | } // if |
---|
[6011658] | 264 | |
---|
[92bfda0] | 265 | // Give the kernel the chance to add some data in here |
---|
| 266 | __kernel_abort_msg( abort_text, abort_text_size ); |
---|
[6011658] | 267 | |
---|
[92bfda0] | 268 | // print stack trace in handler |
---|
| 269 | __cfaabi_backtrace( signalAbort ? 4 : 2 ); |
---|
[6011658] | 270 | |
---|
[92bfda0] | 271 | // Finally call abort |
---|
| 272 | __cabi_libc.abort(); |
---|
[5ccee64] | 273 | |
---|
[8a13c47] | 274 | } |
---|
| 275 | |
---|
| 276 | void abort( const char fmt[], ... ) { |
---|
| 277 | va_list args; |
---|
| 278 | va_start( args, fmt ); |
---|
[d870df3] | 279 | __abort( false, fmt, args ); |
---|
[f883ef1] | 280 | // CONTROL NEVER REACHES HERE! |
---|
[8a13c47] | 281 | va_end( args ); |
---|
| 282 | } |
---|
| 283 | |
---|
[d870df3] | 284 | void abort( bool signalAbort, const char fmt[], ... ) { |
---|
[f883ef1] | 285 | va_list args; |
---|
| 286 | va_start( args, fmt ); |
---|
| 287 | __abort( signalAbort, fmt, args ); |
---|
| 288 | // CONTROL NEVER REACHES HERE! |
---|
| 289 | va_end( args ); |
---|
[d870df3] | 290 | } |
---|
| 291 | |
---|
[dbe9b08] | 292 | void sigHandler_segv( __CFA_SIGPARMS__ ) { |
---|
[8a13c47] | 293 | if ( sfp->si_addr == 0p ) { |
---|
| 294 | abort( true, "Null pointer (0p) dereference.\n" ); |
---|
[1469a8a] | 295 | } else { |
---|
[8a13c47] | 296 | abort( true, "%s at memory location %p.\n" |
---|
[1469a8a] | 297 | "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", |
---|
| 298 | (sig == SIGSEGV ? "Segment fault" : "Bus error"), sfp->si_addr ); |
---|
| 299 | } |
---|
[2b8bc41] | 300 | } |
---|
| 301 | |
---|
| 302 | void sigHandler_ill( __CFA_SIGPARMS__ ) { |
---|
[8a13c47] | 303 | abort( true, "Executing illegal instruction at location %p.\n" |
---|
[2b8bc41] | 304 | "Possible cause is stack corruption.\n", |
---|
| 305 | sfp->si_addr ); |
---|
| 306 | } |
---|
| 307 | |
---|
| 308 | void sigHandler_fpe( __CFA_SIGPARMS__ ) { |
---|
| 309 | const char * msg; |
---|
| 310 | |
---|
[a424315d] | 311 | choose( sfp->si_code ) { |
---|
| 312 | case FPE_INTDIV, FPE_FLTDIV: msg = "divide by zero"; |
---|
| 313 | case FPE_FLTOVF: msg = "overflow"; |
---|
| 314 | case FPE_FLTUND: msg = "underflow"; |
---|
| 315 | case FPE_FLTRES: msg = "inexact result"; |
---|
| 316 | case FPE_FLTINV: msg = "invalid operation"; |
---|
[2b8bc41] | 317 | default: msg = "unknown"; |
---|
[a424315d] | 318 | } // choose |
---|
[8a13c47] | 319 | abort( true, "Computation error %s at location %p.\n", msg, sfp->si_addr ); |
---|
[dbe9b08] | 320 | } |
---|
| 321 | |
---|
[94dea96] | 322 | void sigHandler_term( __CFA_SIGPARMS__ ) { |
---|
[8a13c47] | 323 | abort( true, "Application interrupted by signal: %s.\n", strsignal( sig ) ); |
---|
[94dea96] | 324 | } |
---|
| 325 | |
---|
[6b0b624] | 326 | // Local Variables: // |
---|
| 327 | // mode: c // |
---|
| 328 | // tab-width: 4 // |
---|
| 329 | // End: // |
---|