kconfig: nconf: Ensure null termination where strncpy is used

[ Upstream commit f468992936894c9ce3b1659cf38c230d33b77a16 ]

strncpy() does not guarantee null-termination if the source string is
longer than the destination buffer.

Ensure the buffer is explicitly null-terminated to prevent potential
string overflows or undefined behavior.

Signed-off-by: Shankari Anand <shankari.ak0208@gmail.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Nicolas Schier <n.schier@avm.de>
Acked-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/scripts/kconfig/nconf.c b/scripts/kconfig/nconf.c
index 3ba8b1af390fdc920606c4a70e7c55a43ee947ce..16a2db59432a5f9dc550673dcd73935f1778ef5f 100644 (file)
--- a/scripts/kconfig/nconf.c
+++ b/scripts/kconfig/nconf.c
@@ -585,6 +585,8 @@ static void item_add_str(const char *fmt, ...)
                tmp_str,
                sizeof(k_menu_items[index].str));
 
+       k_menu_items[index].str[sizeof(k_menu_items[index].str) - 1] = '\0';
+
        free_item(curses_menu_items[index]);
        curses_menu_items[index] = new_item(
                        k_menu_items[index].str,

diff --git a/scripts/kconfig/nconf.gui.c b/scripts/kconfig/nconf.gui.c
index 9aedf40f1dc033552adb6e4c14e394f70283641e..da06ea2afe08e5e3b61b28ffbb20b7bbe3185f6c 100644 (file)
--- a/scripts/kconfig/nconf.gui.c
+++ b/scripts/kconfig/nconf.gui.c
@@ -349,6 +349,7 @@ int dialog_inputbox(WINDOW *main_window,
        x = (columns-win_cols)/2;
 
        strncpy(result, init, *result_len);
+       result[*result_len - 1] = '\0';
 
        /* create the windows */
        win = newwin(win_lines, win_cols, y, x);