segment fault in 64bit-mode

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Starting program: /home/fhr/CLionProjects/cb-multios/build64-gcc/challenges/Azurad/Azurad 

Program received signal SIGSEGV, Segmentation fault.
small_alloc_run (heap=<optimized out>) at /home/fhr/CLionProjects/cb-multios/challenges/Azurad/lib/malloc_common.c:224
224         hdr->hdr.prev_size = 0;

Hi, In 64bit-mode, a lot of programs will crash with the segment fault at the start of the running. It's nearly all about cgc_memory function.
How to solve this problem? My env: OS: Ubuntu 20.04LTS compiler : clang-7/ clang-10 / gcc-7 / gcc-9

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@DarkaMaul

[DarkaMaul]

Hi, I'm not on my computer right now but I guess the problem comes from uint_ptr type which is too small. I fixed it for one challenge (FUN?) but it should probably be fixed for every other challenges. I'll try to investigate more next week (prob Tuesday).

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@DarkaMaul Thanks for your reply. I noticed your changes about int&long long int in cgc_stdint.h But I got the same segment fault in FUN challenge.

Program received signal SIGSEGV, Segmentation fault.
cgc_malloc (size=32) at /home/fhr/CLionProjects/cb-multios-n/challenges/FUN/lib/malloc.c:135
135       blk->next->prev = nb;

I find the cgc_size_t in libcgc.h. Should I change them into [ long long int ] ?

typedef unsigned long cgc_size_t;
typedef long cgc_ssize_t; 

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@DarkaMaul for example Segment fault in [XStore] 64bit mode.

I fixed the pointer type but got segment fault in another line. So I think that there might be some other parts which should be fixed.

Program received signal SIGSEGV, Segmentation fault.
0x0000000000403254 in run_alloc (heap=0x40c508 <g_heap>, type=2) at /home/fhr/CLionProjects/cb-multios-n/challenges/XStore/lib/malloc_common.c:93
93      heap->mem_map[alignedi / RUN_SIZE] = type;

[DarkaMaul]

I don't have the time to investigate, but here are my observations so far.

However, they are indeed a few problems:

In cgc_malloc.h

#ifdef X32_COMPILE
 #define HEADER_PADDING 24
#else
 #define HEADER_PADDING 48
#endif

The header size was incorrect since it was comprised of multiple pointers. The command below can be used to change this in a one-liner:

find . -name 'cgc_malloc.h' -exec sed -i "s/\(#define HEADER_PADDING 24\)/#ifdef X32_COMPILE\\n  \1\\n#else\\n  #define HEADER_PADDING 48\\n#endif/" {} \+

Moreover, an improved version of the cgc_stdint.h could be :

#ifdef X32_COMPILE
    # define INT_MIN        INT32_MIN
    # define LONG_MIN       INT32_MIN
    # define INT_MAX        INT32_MAX
    # define UINT_MAX       UINT32_MAX
    # define LONG_MAX       INT32_MAX
    # define ULONG_MAX      UINT32_MAX

    typedef int intptr_t;
    typedef unsigned int uintptr_t;
#else
    # define INT_MIN        INT64_MIN
    # define LONG_MIN       INT64_MIN
    # define INT_MAX        INT64_MAX
    # define UINT_MAX       UINT64_MAX
    # define LONG_MAX       INT64_MAX
    # define ULONG_MAX      UINT64_MAX

    typedef int64_t intptr_t;
    typedef uint64_t uintptr_t;
#endif

However, it is definitely not the only issue. Multiple structures in malloc files depends on the size of the pointers. For example the cgc_size_to_bin rely on specified size of the headers and should also be modified.

I guess it's easier to say that the challenges are "buildable" towards 64 bits architecture but solely for static analysis as they are not yet runnable.

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@DarkaMaul Thank you very very much. I will try to fix them. Best wishes!