kmemleak: use seq_hex_dump() to dump buffers

Instead of custom approach let's use recently introduced seq_hex_dump()
helper.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Joe Perches <joe@perches.com>
Cc: Tadeusz Struk <tadeusz.struk@intel.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Tuchscherer <ingo.tuchscherer@de.ibm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/kmemleak.c

@@ -302,23 +302,14 @@ static void hex_dump_object(struct seq_file *seq,
 			    struct kmemleak_object *object)
 {
 	const u8 *ptr = (const u8 *)object->pointer;
-	int i, len, remaining;
-	unsigned char linebuf[HEX_ROW_SIZE * 5];
+	size_t len;
 
 	/* limit the number of lines to HEX_MAX_LINES */
-	remaining = len =
-		min(object->size, (size_t)(HEX_MAX_LINES * HEX_ROW_SIZE));
-
-	seq_printf(seq, "  hex dump (first %d bytes):\n", len);
-	for (i = 0; i < len; i += HEX_ROW_SIZE) {
-		int linelen = min(remaining, HEX_ROW_SIZE);
-
-		remaining -= HEX_ROW_SIZE;
-		hex_dump_to_buffer(ptr + i, linelen, HEX_ROW_SIZE,
-				   HEX_GROUP_SIZE, linebuf, sizeof(linebuf),
-				   HEX_ASCII);
-		seq_printf(seq, "    %s\n", linebuf);
-	}
+	len = min_t(size_t, object->size, HEX_MAX_LINES * HEX_ROW_SIZE);
+
+	seq_printf(seq, "  hex dump (first %zu bytes):\n", len);
+	seq_hex_dump(seq, "    ", DUMP_PREFIX_NONE, HEX_ROW_SIZE,
+		     HEX_GROUP_SIZE, ptr, len, HEX_ASCII);
 }
 
 /*