AddressSanitizer堆缓冲区溢出错误Leetcode组Anagram问题

这是我的程序：

int cmpfunc (const void * a, const void * b) {
   return ( *(char*)a - *(char*)b );
}

bool isAnagram(char * s, char * t){
    char *str1,*str2;
    if (strlen(s) != strlen(t)) return false;
    char chTemp;
    int len = strlen(s);
    str1 = malloc(len * sizeof(char));
    str2 = malloc(len * sizeof(char));
    strcpy(str1,s);
    strcpy(str2,t);
    qsort(str1,len,sizeof(char),cmpfunc);
    qsort(str2,len,sizeof(char),cmpfunc);
    for (int i = 0; i < len; i++) {
        if (str1[i] != str2[i]) return false;
    }
    return true;
}

char *** groupAnagrams(char ** strs, int strsSize, int* returnSize, int** returnColumnSizes) {
    if (strsSize == 0) return NULL;
    char ***group = (char ***)malloc(strsSize*sizeof(char**));
    for (int i = 0; i < strsSize; i++) {
        group[i] = (char **)malloc(strsSize*sizeof(char*));
        for (int j = 0; j < strsSize; j++) {
            group[i][j] = (char *)malloc(100*sizeof(char));
        }
    } 
    int *used = malloc(strsSize * sizeof(int));
    for (int i = 0; i < strsSize; i++) 
        used[i] = 0;

    *returnColumnSizes = (int *)malloc(strsSize*sizeof(int));
    for (int i = 0; i < strsSize; i++) 
        (*returnColumnSizes)[i] = 0;
    int count = 0;
    if (strsSize == 1) {
          for (int l = 0; l < strlen(strs[0]); l++) {
            group[0][0][l] = strs[0][l];
          }
          count = 1;
          (*returnColumnSizes)[0] = 1;
    } else {
        
        for (int i = 0; i < strsSize-1; i++) {
            int check  = 0;
            int k = 0;
            if (!used[i]) {
                for (int j = i+1; j < strsSize; j++) {
                        if (isAnagram(strs[i],strs[j])) {
                            if (k == 0) {
                                for (int l = 0; l < strlen(strs[i]); l++) {
                                    group[count][0][l] = strs[i][l];
                                }
                                for (int l = 0; l < strlen(strs[j]); l++) {
                                    group[count][1][l] = strs[j][l];
                                }
                                used[i] = 1;
                                used[j] = 1;
                                (*returnColumnSizes)[count] = 2; 
                                count++;
                                k++;
                            } else {
                                (*returnColumnSizes)[count-1]++; 
                                for (int l = 0; l < strlen(strs[j]); l++) {
                                    group[count-1][k+1][l] = strs[j][l];
                                }
                                used[j] = 1;
                                k++;
                            }
                            check = 1;
                        }
                    }
                    if (!check) {
                        for (int l = 0; l < strlen(strs[i]); l++) {
                            group[count][0][l] = strs[i][l];
                        }
                        (*returnColumnSizes)[count] = 1;
                        count++;
                    }
            }
        }
        if (!used[strsSize-1]) {
            for (int l = 0; l < strlen(strs[strsSize-1]); l++) {
                    group[count][0][l] = strs[strsSize-1][l];
            }
            (*returnColumnSizes)[count] = 1;
            count++;
        }
    }
   *returnSize = count;
    free(used);
    return group;
}

谁能告诉我为什么会出现这个错误？

=================================================================
==43==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6020000000d3 at pc 0x7f3b6a2e357d bp 0x7ffc1ee141b0 sp 0x7ffc1ee13958
WRITE of size 4 at 0x6020000000d3 thread T0
    #0 0x7f3b6a2e357c  (/lib/x86_64-linux-gnu/libasan.so.5+0x9b57c)
    #4 0x7f3b697100b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
0x6020000000d3 is located 0 bytes to the right of 3-byte region [0x6020000000d0,0x6020000000d3)
allocated by thread T0 here:
    #0 0x7f3b6a355bc8 in malloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dbc8)
    #4 0x7f3b697100b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)
SUMMARY: AddressSanitizer: heap-buffer-overflow (/lib/x86_64-linux-gnu/libasan.so.5+0x9b57c) 
Shadow bytes around the buggy address:
  0x0c047fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c047fff8000: fa fa 04 fa fa fa 04 fa fa fa 04 fa fa fa 04 fa
=>0x0c047fff8010: fa fa 04 fa fa fa 04 fa fa fa[03]fa fa fa 03 fa
  0x0c047fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c047fff8060: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07 
  Heap left redzone:       fa
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
  Shadow gap:              cc
==43==ABORTING

我想也许我试图访问一个未声明的地址，但我没有看到任何，所以我不知道该怎么办。

您在isAnagram中分配的缓冲区没有为NULL终止符腾出空间：

10,11c10,11
<     str1 = malloc(len * sizeof(char));
<     str2 = malloc(len * sizeof(char));
---
>     str1 = malloc(len * sizeof(char) + 1);
>     str2 = malloc(len * sizeof(char) + 1);

此外，您复制字符串的五个示例不会在缓冲区的末尾写入NULL终止符（CTRL+F group[count）。除此之外，每个字符串只分配了100个char，从LeetCode的描述来看，这与最大长度100相匹配，但没有为NULL终止符留下空间。
您可以屏蔽但不能解决这个问题，方法是清理您分配的字缓冲区，并为NULL终止符添加另一个char：

28c28
<             group[i][j] = (char *)malloc(100*sizeof(char));
---
>             group[i][j] = (char *)calloc(101, sizeof(char));

这两个编辑将让这个解决方案通过大多数情况，但我们最终遇到MLE（内存限制超出），因为您为每次运行分配了不必要的内存量。

AddressSanitizer堆缓冲区溢出错误Leetcode组Anagram问题

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