CrashProbe/CRLCrashCorruptMalloc.m
/*
 * Copyright (c) 2014 HockeyApp, Bit Stadium GmbH.
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 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
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#import "CRLCrashCorruptMalloc.h"
#import <malloc/malloc.h>
#import <mach/mach.h>

@implementation CRLCrashCorruptMalloc

- (NSString *)category { return @"Various"; }
- (NSString *)title { return @"Corrupt malloc()'s internal tracking information"; }
- (NSString *)desc { return @""
  "Write garbage into data areas used by malloc to track memory allocations. "
  "This simulates the kind of heap overflow and/or heap corruption likely to occur in an application; "
  "if the crash reporter itself uses malloc, the corrupted heap will likely trigger a crash in the crash reporter itself.";
}

- (void)crash {
  /* Smash the heap, and keep smashing it until we eventually hit something non-writable, or trigger
   * a malloc error (e.g., in NSLog). */
  uint8_t *memory = malloc(10);
  while (true) {
    NSLog(@"Smashing [%p - %p]", memory, memory + PAGE_SIZE);
    memset((void *) trunc_page((vm_address_t)memory), 0xAB, PAGE_SIZE);
    memory += PAGE_SIZE;
  }
}

@end
