X-Git-Url: http://git.lttng.org/?a=blobdiff_plain;f=probes%2Flttng-probe-user.c;h=cdf7955b63d07dba7e831d45e7cd17eb945ad777;hb=6ccec97391876d0d977a6add820aa0ca13c042d7;hp=94ecf2f1cffb339d53d9c1dc4d62f58a13dc9ece;hpb=7b8ea3a503536c9d00f8bb14958a150cbf7370c0;p=lttng-modules.git

diff --git a/probes/lttng-probe-user.c b/probes/lttng-probe-user.c
index 94ecf2f1..cdf7955b 100644
--- a/probes/lttng-probe-user.c
+++ b/probes/lttng-probe-user.c
@@ -19,6 +19,7 @@
  */
 
 #include <linux/uaccess.h>
+#include <linux/module.h>
 #include "lttng-probe-user.h"
 
 /*
@@ -36,12 +37,16 @@ long lttng_strlen_user_inatomic(const char *addr)
 	pagefault_disable();
 	for (;;) {
 		char v;
-		long ret;
+		unsigned long ret;
 
+		if (unlikely(!access_ok(VERIFY_READ,
+				(__force const char __user *) addr,
+				sizeof(v))))
+			break;
 		ret = __copy_from_user_inatomic(&v,
 			(__force const char __user *)(addr),
 			sizeof(v));
-		if (unlikely(ret == -EFAULT))
+		if (unlikely(ret > 0))
 			break;
 		count++;
 		if (unlikely(!v))
@@ -52,3 +57,4 @@ long lttng_strlen_user_inatomic(const char *addr)
 	set_fs(old_fs);
 	return count;
 }
+EXPORT_SYMBOL_GPL(lttng_strlen_user_inatomic);