From 28669f86f6780a18daca264f32d66b1428c9c6f1 Mon Sep 17 00:00:00 2001 From: Stefan Liebler Date: Thu, 6 Sep 2018 14:27:03 +0200 Subject: [PATCH] Fix segfault in maybe_script_execute. If glibc is built with gcc 8 and -march=z900, the testcase posix/tst-spawn4-compat crashes with a segfault. In function maybe_script_execute, the new_argv array is dynamically initialized on stack with (argc + 1) elements. The function wants to add _PATH_BSHELL as the first argument and writes out of bounds of new_argv. There is an off-by-one because maybe_script_execute fails to count the terminating NULL when sizing new_argv. ChangeLog: * sysdeps/unix/sysv/linux/spawni.c (maybe_script_execute): Increment size of new_argv by one. --- ChangeLog | 5 +++++ sysdeps/unix/sysv/linux/spawni.c | 2 +- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 379b9bd223..0442ed9942 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2018-09-06 Stefan Liebler + + * sysdeps/unix/sysv/linux/spawni.c (maybe_script_execute): + Increment size of new_argv by one. + 2018-09-05 Rafal Luzynski [BZ #17426] diff --git a/sysdeps/unix/sysv/linux/spawni.c b/sysdeps/unix/sysv/linux/spawni.c index cf0213ece5..85239cedbf 100644 --- a/sysdeps/unix/sysv/linux/spawni.c +++ b/sysdeps/unix/sysv/linux/spawni.c @@ -101,7 +101,7 @@ maybe_script_execute (struct posix_spawn_args *args) ptrdiff_t argc = args->argc; /* Construct an argument list for the shell. */ - char *new_argv[argc + 1]; + char *new_argv[argc + 2]; new_argv[0] = (char *) _PATH_BSHELL; new_argv[1] = (char *) args->file; if (argc > 1)