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// RUN: %clang_analyze_cc1 -analyzer-checker=core,unix.Malloc -verify %s
//
typedef __SIZE_TYPE__ size_t;
typedef enum memory_order {
memory_order_relaxed = __ATOMIC_RELAXED,
} memory_order;
void *calloc(size_t, size_t);
void free(void *);
struct SomeData {
int i;
_Atomic int ref;
};
static struct SomeData *alloc_data(void)
{
struct SomeData *data = calloc(sizeof(*data), 1);
__c11_atomic_store(&data->ref, 2, memory_order_relaxed);
return data;
}
static void put_data(struct SomeData *data)
{
if (__c11_atomic_fetch_sub(&data->ref, 1, memory_order_relaxed) == 1)
free(data);
}
static int dec_refcounter(struct SomeData *data)
{
return __c11_atomic_fetch_sub(&data->ref, 1, memory_order_relaxed) == 1;
}
static void put_data_nested(struct SomeData *data)
{
if (dec_refcounter(data))
free(data);
}
static void put_data_uncond(struct SomeData *data)
{
free(data);
}
static void put_data_unrelated_atomic(struct SomeData *data)
{
free(data);
__c11_atomic_fetch_sub(&data->ref, 1, memory_order_relaxed);
}
void test_no_uaf(void)
{
struct SomeData *data = alloc_data();
put_data(data);
data->i += 1; // no warning
}
void test_no_uaf_nested(void)
{
struct SomeData *data = alloc_data();
put_data_nested(data);
data->i += 1; // no warning
}
void test_uaf(void)
{
struct SomeData *data = alloc_data();
put_data_uncond(data);
data->i += 1; // expected-warning{{Use of memory after it is freed}}
}
void test_no_uaf_atomic_after(void)
{
struct SomeData *data = alloc_data();
put_data_unrelated_atomic(data);
data->i += 1; // expected-warning{{Use of memory after it is freed}}
}
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