fix: don't allow userspace copy to read kernel memory

[lttng-modules.git] / src / probes / lttng-probe-user.c

diff --git a/src/probes/lttng-probe-user.c b/src/probes/lttng-probe-user.c
index 592d948b1498e66f570ae8cc2a9e6906304a1750..91190f7ba6e3152ea643a2c44b28bb7b7b2b97be 100644 (file)
--- a/src/probes/lttng-probe-user.c
+++ b/src/probes/lttng-probe-user.c
@@ -21,13 +21,10 @@
 long lttng_strlen_user_inatomic(const char *addr)
 {
        long count = 0;
-       mm_segment_t old_fs;
 
        if (!addr)
                return 0;
 
-       old_fs = get_fs();
-       set_fs(KERNEL_DS);
        pagefault_disable();
        for (;;) {
                char v;
@@ -50,7 +47,6 @@ long lttng_strlen_user_inatomic(const char *addr)
                addr++;
        }
        pagefault_enable();
-       set_fs(old_fs);
        return count;
 }
 EXPORT_SYMBOL_GPL(lttng_strlen_user_inatomic);