py/builtinevex: Handle invalid filenames for execfile.

If a non-string buffer was passed to execfile, then it would be passed
as a non-null-terminated char* to mp_lexer_new_from_file.

This changes mp_lexer_new_from_file to take a qstr instead (as in almost
all cases a qstr will be created from this input anyway to set the
`__file__` attribute on the module).

This now makes execfile require a string (not generic buffer) argument,
which is probably a good fix to make anyway.

Fixes issue #12522.

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/ports/esp8266/main.c b/ports/esp8266/main.c
index 7c940ac2a..87e72bace 100644
--- a/ports/esp8266/main.c
+++ b/ports/esp8266/main.c
@@ -141,7 +141,7 @@ void user_init(void) {
 }
 
 #if !MICROPY_VFS
-mp_lexer_t *mp_lexer_new_from_file(const char *filename) {
+mp_lexer_t *mp_lexer_new_from_file(qstr filename) {
     mp_raise_OSError(MP_ENOENT);
 }