X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=probes%2Flttng-probe-user.c;h=dc6cca1ba0037521e73756da831a5d6c4b4da4a9;hb=f127e61ee231d002fb9a7803643a157e06f6d2e2;hp=d0b5cf297367ce3c209b69ecb491e969ec321270;hpb=07dfc1d0e4b093ad02682499a702dc11e54e8302;p=lttng-modules.git

diff --git a/probes/lttng-probe-user.c b/probes/lttng-probe-user.c
index d0b5cf29..dc6cca1b 100644
--- a/probes/lttng-probe-user.c
+++ b/probes/lttng-probe-user.c
@@ -38,6 +38,10 @@ long lttng_strlen_user_inatomic(const char *addr)
 		char v;
 		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));
@@ -52,3 +56,4 @@ long lttng_strlen_user_inatomic(const char *addr)
 	set_fs(old_fs);
 	return count;
 }
+EXPORT_SYMBOL_GPL(lttng_strlen_user_inatomic);