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ipxe/src/arch/i386/core/nulltrap.c

nulltrap.c 2.1KB
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  1. #include <stdint.h>

  2. #include <stdio.h>

  3. 

  4. __attribute__ (( noreturn, section ( ".text.null_trap" ) ))

  5. void null_function_trap ( void ) {

  6. 	void *stack;

  7. 

  8. 	/* 128 bytes of NOPs; the idea of this is that if something

  9. 	 * dereferences a NULL pointer and overwrites us, we at least

  10. 	 * have some chance of still getting to execute the printf()

  11. 	 * statement.

  12. 	 */

  13. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  14. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  15. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  16. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  17. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  18. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  19. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  20. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  21. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  22. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  23. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  24. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  25. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  26. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  27. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  28. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  29. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  30. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  31. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  32. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  33. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  34. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  35. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  36. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  37. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  38. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  39. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  40. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  41. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  42. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  43. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  44. 	__asm__ __volatile__ ( "nop ; nop ; nop ; nop" );

  45. 

  46. 	__asm__ __volatile__ ( "movl %%esp, %0" : "=r" ( stack ) );

  47. 	printf ( "NULL method called from %p (stack %p)\n", 

  48. 		 __builtin_return_address ( 0 ), stack );

  49. 	DBG_HD ( stack, 256 );

  50. 	while ( 1 ) {}

  51. }