qcacmn: Fix file name tracking logic in QDF nbuf tracker

As WIN has multiple modules and QDF is the last one to be unloaded,
QDF is crashing when it tried to print the file name of an nbuf
allocated by other modules. To fix this, copy the file name in the
QDF nbuf tracker, rather than using the pointer to file name,
to avoid access to the invalid pointer.

CRs-Fixed: 2258770
Change-Id: I27ee76e58b0f5a976840783cfeba451784de85dd

qdf/inc/qdf_mem.h

@@ -86,6 +86,8 @@ void qdf_mem_init(void);
  */
 void qdf_mem_exit(void);
 
+#define QDF_MEM_FILE_NAME_SIZE 48
+
 #ifdef MEMORY_DEBUG
 /**
  * qdf_mem_malloc_debug() - debug version of QDF memory allocation API

qdf/linux/src/qdf_mem.c

@@ -56,7 +56,6 @@
 #define QDF_MEM_MAX_MALLOC (4096 * 1024) /* 4 Mega Bytes */
 #define QDF_MEM_WARN_THRESHOLD 300 /* ms */
 #define QDF_DEBUG_STRING_SIZE 512
-#define QDF_MEM_FILE_NAME_SIZE 48
 
 static qdf_list_t qdf_mem_domains[QDF_DEBUG_DOMAIN_COUNT];
 static qdf_spinlock_t qdf_mem_list_lock;

qdf/linux/src/qdf_nbuf.c

@@ -41,6 +41,7 @@
 #include <qdf_atomic.h>
 #include <pld_common.h>
 #include <qdf_module.h>
+#include "qdf_str.h"
 
 #if defined(FEATURE_TSO)
 #include <net/ipv6.h>
@@ -543,7 +544,7 @@ enum qdf_nbuf_event_type {
 
 struct qdf_nbuf_event {
 	qdf_nbuf_t nbuf;
-	const char *file;
+	char file[QDF_MEM_FILE_NAME_SIZE];
 	uint32_t line;
 	enum qdf_nbuf_event_type type;
 	uint64_t timestamp;
@@ -572,7 +573,7 @@ qdf_nbuf_history_add(qdf_nbuf_t nbuf, const char *file, uint32_t line,
 	struct qdf_nbuf_event *event = &qdf_nbuf_history[idx];
 
 	event->nbuf = nbuf;
-	event->file = file;
+	qdf_str_lcopy(event->file, kbasename(file), QDF_MEM_FILE_NAME_SIZE);
 	event->line = line;
 	event->type = type;
 	event->timestamp = qdf_get_log_timestamp();
@@ -581,7 +582,7 @@ qdf_nbuf_history_add(qdf_nbuf_t nbuf, const char *file, uint32_t line,
 struct qdf_nbuf_map_metadata {
 	struct hlist_node node;
 	qdf_nbuf_t nbuf;
-	const char *file;
+	char file[QDF_MEM_FILE_NAME_SIZE];
 	uint32_t line;
 };
 
@@ -627,7 +628,7 @@ void qdf_nbuf_map_check_for_leaks(void)
 	hash_for_each(qdf_nbuf_map_ht, bucket, meta, node) {
 		count++;
 		qdf_err("0x%pk @ %s:%u",
-			meta->nbuf, kbasename(meta->file), meta->line);
+			meta->nbuf, meta->file, meta->line);
 	}
 	qdf_spin_unlock_irqrestore(&qdf_nbuf_map_lock);
 
@@ -678,7 +679,7 @@ qdf_nbuf_track_map(qdf_nbuf_t nbuf, const char *file, uint32_t line)
 	}
 
 	meta->nbuf = nbuf;
-	meta->file = file;
+	qdf_str_lcopy(meta->file, kbasename(file), QDF_MEM_FILE_NAME_SIZE);
 	meta->line = line;
 
 	qdf_spin_lock_irqsave(&qdf_nbuf_map_lock);
@@ -2078,7 +2079,7 @@ qdf_export_symbol(__qdf_nbuf_is_bcast_pkt);
 struct qdf_nbuf_track_t {
 	struct qdf_nbuf_track_t *p_next;
 	qdf_nbuf_t net_buf;
-	uint8_t *file_name;
+	char file_name[QDF_MEM_FILE_NAME_SIZE];
 	uint32_t line_num;
 	size_t size;
 };
@@ -2464,13 +2465,14 @@ void qdf_net_buf_debug_add_node(qdf_nbuf_t net_buf, size_t size,
 	if (p_node) {
 		qdf_print("Double allocation of skb ! Already allocated from %pK %s %d current alloc from %pK %s %d",
 			  p_node->net_buf, p_node->file_name, p_node->line_num,
-			  net_buf, file_name, line_num);
+			  net_buf, kbasename(file_name), line_num);
 		qdf_nbuf_track_free(new_node);
 	} else {
 		p_node = new_node;
 		if (p_node) {
 			p_node->net_buf = net_buf;
-			p_node->file_name = file_name;
+			qdf_str_lcopy(p_node->file_name, kbasename(file_name),
+				      QDF_MEM_FILE_NAME_SIZE);
 			p_node->line_num = line_num;
 			p_node->size = size;
 			qdf_mem_skb_inc(size);
@@ -2479,7 +2481,7 @@ void qdf_net_buf_debug_add_node(qdf_nbuf_t net_buf, size_t size,
 		} else
 			qdf_print(
 				  "Mem alloc failed ! Could not track skb from %s %d of size %zu",
-				  file_name, line_num, size);
+				  kbasename(file_name), line_num, size);
 	}
 
 	spin_unlock_irqrestore(&g_qdf_net_buf_track_lock[i], irq_flag);