From 64f0425b0f606a3f6c4d09c052cc878415560bf5 Mon Sep 17 00:00:00 2001 From: Pablo Galindo Salgado Date: Tue, 16 Nov 2021 19:51:52 +0000 Subject: [PATCH] bpo-45820: Fix a segfault when the parser fails without reading any input (GH-29580) (cherry picked from commit df4ae55e66e34ea8de6a34f0b104871ddaf35d53) Co-authored-by: Pablo Galindo Salgado --- .../2021-11-16-19-00-27.bpo-45820.2X6Psr.rst | 2 ++ Parser/pegen.c | 8 ++++++++ 2 files changed, 10 insertions(+) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2021-11-16-19-00-27.bpo-45820.2X6Psr.rst diff --git a/Misc/NEWS.d/next/Core and Builtins/2021-11-16-19-00-27.bpo-45820.2X6Psr.rst b/Misc/NEWS.d/next/Core and Builtins/2021-11-16-19-00-27.bpo-45820.2X6Psr.rst new file mode 100644 index 00000000000000..c2ec3d690cd4bc --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2021-11-16-19-00-27.bpo-45820.2X6Psr.rst @@ -0,0 +1,2 @@ +Fix a segfault when the parser fails without reading any input. Patch by +Pablo Galindo diff --git a/Parser/pegen.c b/Parser/pegen.c index cfb4b8e8fb1576..ed5bb177fead64 100644 --- a/Parser/pegen.c +++ b/Parser/pegen.c @@ -389,6 +389,14 @@ tokenizer_error(Parser *p) void * _PyPegen_raise_error(Parser *p, PyObject *errtype, const char *errmsg, ...) { + if (p->fill == 0) { + va_list va; + va_start(va, errmsg); + _PyPegen_raise_error_known_location(p, errtype, 0, 0, 0, -1, errmsg, va); + va_end(va); + return NULL; + } + Token *t = p->known_err_token != NULL ? p->known_err_token : p->tokens[p->fill - 1]; Py_ssize_t col_offset; Py_ssize_t end_col_offset = -1;