X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=probes%2Flttng-events.h;h=d486994f3a0c2202741037c8ef68ffe5ebd16bc5;hb=c0be14c235542c5852d96b9b840c44a29349b002;hp=084666d56514520f7db875e6026bf538eef0cfbd;hpb=4ea00e4f764eb18686121161a98e4ef442fed2c0;p=lttng-modules.git

diff --git a/probes/lttng-events.h b/probes/lttng-events.h
index 084666d5..d486994f 100644
--- a/probes/lttng-events.h
+++ b/probes/lttng-events.h
@@ -188,6 +188,10 @@ void trace_##_name(void *__data);
 		},						\
 	},
 
+#undef __string_from_user
+#define __string_from_user(_item, _src)				\
+	__string(_item, _src)
+
 #undef TP_STRUCT__entry
 #define TP_STRUCT__entry(args...) args	/* Only one used in this phase */
 
@@ -336,6 +340,15 @@ static __used struct lttng_probe_desc TP_ID(__probe_desc___, TRACE_SYSTEM) = {
 #define __string(_item, _src)						       \
 	__event_len += __dynamic_len[__dynamic_len_idx++] = strlen(_src) + 1;
 
+/*
+ * strlen_user includes \0. If returns 0, it faulted, so we set size to
+ * 1 (\0 only).
+ */
+#undef __string_from_user
+#define __string_from_user(_item, _src)					       \
+	__event_len += __dynamic_len[__dynamic_len_idx++] =		       \
+		max_t(size_t, strlen_user(_src), 1);
+
 #undef TP_PROTO
 #define TP_PROTO(args...) args
 
@@ -383,6 +396,9 @@ static inline size_t __event_get_size__##_name(size_t *__dynamic_len, _proto) \
 #undef __string
 #define __string(_item, _src)
 
+#undef __string_from_user
+#define __string_from_user(_item, _src)
+
 #undef TP_PROTO
 #define TP_PROTO(args...) args
 
@@ -424,7 +440,11 @@ static inline size_t __event_get_align__##_name(_proto)			      \
 	_type	_item;
 
 #undef __string
-#define __string(_item, _src)	char _item;
+#define __string(_item, _src)			char _item;
+
+#undef __string_from_user
+#define __string_from_user(_item, _src)		\
+	__string(_item, _src)
 
 #undef TP_STRUCT__entry
 #define TP_STRUCT__entry(args...) args
@@ -473,6 +493,10 @@ __end_field_##_item##_2:
 	goto __assign_##_item;						\
 __end_field_##_item:
 
+#undef __string_from_user
+#define __string_from_user(_item, _src)					\
+	__string(_item, _src)
+
 /*
  * Macros mapping tp_assign() to "=", tp_memcpy() to memcpy() and tp_strcpy() to
  * strcpy().
@@ -510,6 +534,7 @@ __assign_##dest##_2:							\
 	__chan->ops->event_write(&__ctx, src,				\
 		sizeof(__typemap.dest) * __get_dynamic_array_len(dest));\
 	goto __end_field_##dest##_2;
+
 #undef tp_memcpy_from_user
 #define tp_memcpy_from_user(dest, src, len)				\
 	__assign_##dest:						\
@@ -518,20 +543,27 @@ __assign_##dest##_2:							\
 	lib_ring_buffer_align_ctx(&__ctx, ltt_alignof(__typemap.dest));	\
 	__chan->ops->event_write_from_user(&__ctx, src, len);		\
 	goto __end_field_##dest;
+
 /*
- * tp_copy_string_from_user "len" parameter is the length of the string
- * excluding the final \0.
+ * The string length including the final \0.
  */
 #undef tp_copy_string_from_user
-#define tp_copy_string_from_user(dest, src, len)			\
+#define tp_copy_string_from_user(dest, src)				\
 	__assign_##dest:						\
-	if (0)								\
-		(void) __typemap.dest;					\
-	lib_ring_buffer_align_ctx(&__ctx, ltt_alignof(__typemap.dest));	\
-	__chan->ops->event_write_from_user(&__ctx, src, len);		\
-	__chan->ops->event_memset(&__ctx, 0, 1);			\
+	{								\
+		size_t __ustrlen;					\
+									\
+		if (0)							\
+			(void) __typemap.dest;				\
+		lib_ring_buffer_align_ctx(&__ctx, ltt_alignof(__typemap.dest));\
+		__ustrlen = __get_dynamic_array_len(dest);		\
+		if (likely(__ustrlen > 1)) {				\
+			__chan->ops->event_write_from_user(&__ctx, src,	\
+				__ustrlen - 1);				\
+		}							\
+		__chan->ops->event_memset(&__ctx, 0, 1);		\
+	}								\
 	goto __end_field_##dest;
-
 #undef tp_strcpy
 #define tp_strcpy(dest, src)						\
 	tp_memcpy(dest, src, __get_dynamic_array_len(dest))