lssubsys: Fix strncpy() truncation warning

Fix the following strncpy() string truncation warning:

In function ‘strncpy’,
    inlined from ‘print_all_controllers_in_hierarchy’ at lssubsys.c:131:4,
    inlined from ‘cgroup_list_all_controllers’ at lssubsys.c:225:9,
    inlined from ‘main’ at lssubsys.c:293:8:
/usr/include/x86_64-linux-gnu/bits/string_fortified.h:106:10: warning: ‘__builtin_strncpy’ output may be truncated copying 4095 bytes from a string of length 4095 [-Wstringop-truncation]
  106 |   return __builtin___strncpy_chk (__dest, __src, __len, __bos (__dest));
      |          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>

diff --git a/src/tools/lssubsys.c b/src/tools/lssubsys.c
index a6713b8bf0669f0c662893a9d1d8730697def99c..bf73b9d2d8897fb718ae1a78c418d766366332d0 100644 (file)
--- a/src/tools/lssubsys.c
+++ b/src/tools/lssubsys.c
@@ -129,6 +129,7 @@ static int print_all_controllers_in_hierarchy(const char *tname,
 
                        memset(cont_names, 0, FILENAME_MAX);
                        strncpy(cont_names, info.name, FILENAME_MAX-1);
+                       cont_names[sizeof(cont_names) - 1] = '\0';
                        first = 0;
                } else {
                        /* the next controller in the hierarchy */