bpf-tools: Add new feature(leaksanitizer) on BPF CO-RE

Add leaksanitizer(lsan) feature on BPF CO-RE
lsan feature originally comes from llvm-project
https://github.com/llvm/llvm-project
cvector.h comes from c-vector project
https://github.com/eteran/c-vector
uthash.h comes from uthash project
https://github.com/troydhanson/uthash
This tool detect and report dangling pointers periodically

Usage: lsan [OPTION...]
Detect memory leak resulting from dangling pointers.

Either -c or -p is a mandatory option
EXAMPLES:
    lsan -p 1234             # Detect leaks on process id 1234
    lsan -c a.out            # Detect leaks on a.out
    lsan -c 'a.out arg'      # Detect leaks on a.out with argument
    lsan -c "a.out arg"      # Detect leaks on a.out with argument

  -c, --command=COMMAND      Execute and trace the specified command
  -i, --interval=INTERVAL    Set interval in second to detect leak
  -p, --pid=PID              Set pid
  -s, --suppressions=SUPPRESSIONS
                             Suppressions file name
  -T, --top=TOP              Report only specified amount of backtraces
  -v, --verbose              Verbose debug output
  -w, --stop-the-world       Stop the world during tracing
  -?, --help                 Give this help list
      --usage                Give a short usage message
  -V, --version              Print program version

Mandatory or optional arguments to long options are also mandatory or optional
for any corresponding short options.

Report example:
$ sudo ./lsan -c a.out -s suppr.txt
Info: Execute child process: a.out
Info: execute command: a.out(pid 8335)

[2022-07-19 16:07:26] Print leaks:
Could not open [uprobes]
4 bytes direct leak found in 1 allocations from stack id(19863)
        #1 0x00564465ed71bf foo
        #2 0x00564465ed721b main
        #3 0x007fc0a33f7d90 __libc_init_first

[2022-07-19 16:07:36] Print leaks:
8 bytes direct leak found in 2 allocations from stack id(19863)
        #1 0x00564465ed71bf foo
        #2 0x00564465ed721b main
        #3 0x007fc0a33f7d90 __libc_init_first

[2022-07-19 16:07:46] Print leaks:
12 bytes direct leak found in 3 allocations from stack id(19863)
        #1 0x00564465ed71bf foo
        #2 0x00564465ed721b main
        #3 0x007fc0a33f7d90 __libc_init_first

Source code of test program:
\#include <stdio.h>
\#include <stdlib.h>
\#include <unistd.h>

int* foo() {
        int *tmp = malloc(sizeof(int));
        *tmp = 99;
        return tmp;
}

int* bar() {
        int *tmp = malloc(sizeof(int));
        *tmp = 22;
        return tmp;
}

int main() {
        int *a = NULL;
        while (1) {
                a = foo();
                printf("%d\n", *a);
                a = bar();
                free(a);
                sleep(10);
        }
}

Author: Bojun-Seo

libbpf-tools/Makefile

@@ -41,6 +41,7 @@ APPS = \
 	hardirqs \
 	klockstat \
 	ksnoop \
+	lsan \
 	llcstat \
 	mdflush \
 	mountsnoop \

libbpf-tools/cvector.h

@@ -0,0 +1,198 @@
+
+#ifndef CVECTOR_H_
+#define CVECTOR_H_
+
+#include <assert.h> /* for assert */
+#include <stdlib.h> /* for malloc/realloc/free */
+
+/**
+ * @brief cvector_vector_type - The vector type used in this library
+ */
+#define cvector_vector_type(type) type *
+
+/**
+ * @brief cvector_set_capacity - For internal use, sets the capacity variable of the vector
+ * @param vec - the vector
+ * @param size - the new capacity to set
+ * @return void
+ */
+#define cvector_set_capacity(vec, size)     \
+	do {                                    \
+		if (vec) {                          \
+			((size_t *)(vec))[-1] = (size); \
+		}                                   \
+	} while (0)
+
+/**
+ * @brief cvector_set_size - For internal use, sets the size variable of the vector
+ * @param vec - the vector
+ * @param size - the new capacity to set
+ * @return void
+ */
+#define cvector_set_size(vec, size)         \
+	do {                                    \
+		if (vec) {                          \
+			((size_t *)(vec))[-2] = (size); \
+		}                                   \
+	} while (0)
+
+/**
+ * @brief cvector_capacity - gets the current capacity of the vector
+ * @param vec - the vector
+ * @return the capacity as a size_t
+ */
+#define cvector_capacity(vec) \
+	((vec) ? ((size_t *)(vec))[-1] : (size_t)0)
+
+/**
+ * @brief cvector_size - gets the current size of the vector
+ * @param vec - the vector
+ * @return the size as a size_t
+ */
+#define cvector_size(vec) \
+	((vec) ? ((size_t *)(vec))[-2] : (size_t)0)
+
+/**
+ * @brief cvector_empty - returns non-zero if the vector is empty
+ * @param vec - the vector
+ * @return non-zero if empty, zero if non-empty
+ */
+#define cvector_empty(vec) \
+	(cvector_size(vec) == 0)
+
+/**
+ * @brief cvector_grow - For internal use, ensures that the vector is at least <count> elements big
+ * @param vec - the vector
+ * @param count - the new capacity to set
+ * @return void
+ */
+#define cvector_grow(vec, count)                                              \
+	do {                                                                      \
+		const size_t cv_sz = (count) * sizeof(*(vec)) + (sizeof(size_t) * 2); \
+		if (!(vec)) {                                                         \
+			size_t *cv_p = malloc(cv_sz);                                     \
+			assert(cv_p);                                                     \
+			(vec) = (void *)(&cv_p[2]);                                       \
+			cvector_set_capacity((vec), (count));                             \
+			cvector_set_size((vec), 0);                                       \
+		} else {                                                              \
+			size_t *cv_p1 = &((size_t *)(vec))[-2];                           \
+			size_t *cv_p2 = realloc(cv_p1, (cv_sz));                          \
+			assert(cv_p2);                                                    \
+			(vec) = (void *)(&cv_p2[2]);                                      \
+			cvector_set_capacity((vec), (count));                             \
+		}                                                                     \
+	} while (0)
+
+/**
+ * @brief cvector_pop_back - removes the last element from the vector
+ * @param vec - the vector
+ * @return void
+ */
+#define cvector_pop_back(vec)                           \
+	do {                                                \
+		cvector_set_size((vec), cvector_size(vec) - 1); \
+	} while (0)
+
+/**
+ * @brief cvector_erase - removes the element at index i from the vector
+ * @param vec - the vector
+ * @param i - index of element to remove
+ * @return void
+ */
+#define cvector_erase(vec, i)                                  \
+	do {                                                       \
+		if (vec) {                                             \
+			const size_t cv_sz = cvector_size(vec);            \
+			if ((i) < cv_sz) {                                 \
+				cvector_set_size((vec), cv_sz - 1);            \
+				size_t cv_x;                                   \
+				for (cv_x = (i); cv_x < (cv_sz - 1); ++cv_x) { \
+					(vec)[cv_x] = (vec)[cv_x + 1];             \
+				}                                              \
+			}                                                  \
+		}                                                      \
+	} while (0)
+
+/**
+ * @brief cvector_free - frees all memory associated with the vector
+ * @param vec - the vector
+ * @return void
+ */
+#define cvector_free(vec)                        \
+	do {                                         \
+		if (vec) {                               \
+			size_t *p1 = &((size_t *)(vec))[-2]; \
+			free(p1);                            \
+		}                                        \
+	} while (0)
+
+/**
+ * @brief cvector_begin - returns an iterator to first element of the vector
+ * @param vec - the vector
+ * @return a pointer to the first element (or NULL)
+ */
+#define cvector_begin(vec) \
+	(vec)
+
+/**
+ * @brief cvector_end - returns an iterator to one past the last element of the vector
+ * @param vec - the vector
+ * @return a pointer to one past the last element (or NULL)
+ */
+#define cvector_end(vec) \
+	((vec) ? &((vec)[cvector_size(vec)]) : NULL)
+
+/* user request to use logarithmic growth algorithm */
+#ifdef CVECTOR_LOGARITHMIC_GROWTH
+
+/**
+ * @brief cvector_push_back - adds an element to the end of the vector
+ * @param vec - the vector
+ * @param value - the value to add
+ * @return void
+ */
+#define cvector_push_back(vec, value)                               \
+	do {                                                            \
+		size_t cv_cap = cvector_capacity(vec);                      \
+		if (cv_cap <= cvector_size(vec)) {                          \
+			cvector_grow((vec), !cv_cap ? cv_cap + 1 : cv_cap * 2); \
+		}                                                           \
+		vec[cvector_size(vec)] = (value);                           \
+		cvector_set_size((vec), cvector_size(vec) + 1);             \
+	} while (0)
+
+#else
+
+/**
+ * @brief cvector_push_back - adds an element to the end of the vector
+ * @param vec - the vector
+ * @param value - the value to add
+ * @return void
+ */
+#define cvector_push_back(vec, value)                   \
+	do {                                                \
+		size_t cv_cap = cvector_capacity(vec);          \
+		if (cv_cap <= cvector_size(vec)) {              \
+			cvector_grow((vec), cv_cap + 1);            \
+		}                                               \
+		vec[cvector_size(vec)] = (value);               \
+		cvector_set_size((vec), cvector_size(vec) + 1); \
+	} while (0)
+
+#endif /* CVECTOR_LOGARITHMIC_GROWTH */
+
+/**
+ * @brief cvector_copy - copy a vector
+ * @param from - the original vector
+ * @param to - destination to which the function copy to
+ * @return void
+ */
+#define cvector_copy(from, to)									\
+	do {														\
+		for(size_t i = 0; i < cvector_size(from); i++) {		\
+			cvector_push_back(to, from[i]);						\
+		}														\
+	} while (0)													\
+
+#endif /* CVECTOR_H_ */