Coverage Report

Created: 2025-08-27 07:03

/src/dropbear/src/dbmalloc.c
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Count
Source (jump to first uncovered line)
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#include "dbmalloc.h"
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#include "dbutil.h"
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21.2k
void * m_calloc(size_t nmemb, size_t size) {
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21.2k
    if (SIZE_T_MAX / nmemb < size) {
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0
        dropbear_exit("m_calloc failed");
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0
    }
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21.2k
    return m_malloc(nmemb*size);
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21.2k
}
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9.57k
void * m_strdup(const char * str) {
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9.57k
    char* ret;
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9.57k
    unsigned int len;
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9.57k
    len = strlen(str);
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9.57k
    ret = m_malloc(len+1);
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9.57k
    if (ret == NULL) {
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0
        dropbear_exit("m_strdup failed");
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0
    }
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9.57k
    memcpy(ret, str, len+1);
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9.57k
    return ret;
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9.57k
}
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#if !DROPBEAR_TRACKING_MALLOC
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/* Simple wrappers around malloc etc */
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void * m_malloc(size_t size) {
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  void* ret;
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  if (size == 0) {
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    dropbear_exit("m_malloc failed");
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  }
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  ret = calloc(1, size);
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  if (ret == NULL) {
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    dropbear_exit("m_malloc failed");
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  }
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  return ret;
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}
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void * m_realloc(void* ptr, size_t size) {
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  void *ret;
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  if (size == 0) {
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    dropbear_exit("m_realloc failed");
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  }
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  ret = realloc(ptr, size);
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  if (ret == NULL) {
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    dropbear_exit("m_realloc failed");
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  }
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  return ret;
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}
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#else
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/* For fuzzing */
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struct dbmalloc_header {
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    unsigned int epoch;
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    struct dbmalloc_header *prev;
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    struct dbmalloc_header *next;
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};
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static void put_alloc(struct dbmalloc_header *header);
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static void remove_alloc(struct dbmalloc_header *header);
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/* end of the linked list */
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static struct dbmalloc_header* staple;
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unsigned int current_epoch = 0;
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2.99k
void m_malloc_set_epoch(unsigned int epoch) {
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2.99k
    current_epoch = epoch;
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2.99k
}
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2.99k
void m_malloc_free_epoch(unsigned int epoch, int dofree) {
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2.99k
    struct dbmalloc_header* header;
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2.99k
    struct dbmalloc_header* nextheader = NULL;
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2.99k
    struct dbmalloc_header* oldstaple = staple;
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2.99k
    staple = NULL;
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    /* free allocations from this epoch, create a new staple-anchored list from
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    the remainder */
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3.11M
    for (header = oldstaple; header; header = nextheader)
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3.11M
    {
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3.11M
        nextheader = header->next;
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3.11M
        if (header->epoch == epoch) {
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919
            if (dofree) {
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919
                free(header);
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919
            }
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3.11M
        } else {
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3.11M
            header->prev = NULL;
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3.11M
            header->next = NULL;
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3.11M
            put_alloc(header);
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3.11M
        }
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3.11M
    }
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2.99k
}
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3.54M
static void put_alloc(struct dbmalloc_header *header) {
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3.54M
    assert(header->next == NULL);
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3.54M
    assert(header->prev == NULL);
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3.54M
    if (staple) {
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3.53M
        staple->prev = header;
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3.53M
    }
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3.54M
    header->next = staple;
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3.54M
    staple = header;
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3.54M
}
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423k
static void remove_alloc(struct dbmalloc_header *header) {
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423k
    if (header->prev) {
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187k
        header->prev->next = header->next;
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187k
    }
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423k
    if (header->next) {
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423k
        header->next->prev = header->prev;
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423k
    }
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423k
    if (staple == header) {
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236k
        staple = header->next;
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    }
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423k
    header->prev = NULL;
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423k
    header->next = NULL;
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423k
}
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423k
static struct dbmalloc_header* get_header(void* ptr) {
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423k
    char* bptr = ptr;
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423k
    return (struct dbmalloc_header*)&bptr[-sizeof(struct dbmalloc_header)];
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423k
}
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413k
void * m_malloc(size_t size) {
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413k
    char* mem = NULL;
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413k
    struct dbmalloc_header* header = NULL;
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413k
    if (size == 0 || size > 1e9) {
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0
        dropbear_exit("m_malloc failed");
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0
    }
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413k
    size = size + sizeof(struct dbmalloc_header);
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413k
    mem = calloc(1, size);
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413k
    if (mem == NULL) {
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0
        dropbear_exit("m_malloc failed");
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0
    }
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413k
    header = (struct dbmalloc_header*)mem;
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413k
    put_alloc(header);
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413k
    header->epoch = current_epoch;
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413k
    return &mem[sizeof(struct dbmalloc_header)];
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413k
}
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13.4k
void * m_realloc(void* ptr, size_t size) {
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13.4k
    char* mem = NULL;
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13.4k
    struct dbmalloc_header* header = NULL;
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13.4k
    if (size == 0 || size > 1e9) {
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0
        dropbear_exit("m_realloc failed");
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0
    }
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13.4k
    header = get_header(ptr);
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13.4k
    remove_alloc(header);
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13.4k
    size = size + sizeof(struct dbmalloc_header);
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13.4k
    mem = realloc(header, size);
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13.4k
    if (mem == NULL) {
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0
        dropbear_exit("m_realloc failed");
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0
    }
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13.4k
    header = (struct dbmalloc_header*)mem;
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13.4k
    put_alloc(header);
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13.4k
    return &mem[sizeof(struct dbmalloc_header)];
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13.4k
}
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428k
void m_free_direct(void* ptr) {
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428k
    struct dbmalloc_header* header = NULL;
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428k
    if (!ptr) {
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18.5k
        return;
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18.5k
    }
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410k
    header = get_header(ptr);
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410k
    remove_alloc(header);
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410k
    free(header);
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410k
}
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#endif /* DROPBEAR_TRACKING_MALLOC */
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1.67k
void * m_realloc_ltm(void* ptr, size_t oldsize, size_t newsize) {
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1.67k
   (void)oldsize;
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1.67k
   return m_realloc(ptr, newsize);
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1.67k
}
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21.1k
void m_free_ltm(void *mem, size_t size) {
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21.1k
   (void)size;
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21.1k
   m_free_direct(mem);
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21.1k
}