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.
This commit is contained in:
Stefan Liebler 2018-09-06 14:27:03 +02:00
parent a33650d1a6
commit 28669f86f6
2 changed files with 6 additions and 1 deletions

View File

@ -1,3 +1,8 @@
2018-09-06 Stefan Liebler <stli@linux.ibm.com>
* sysdeps/unix/sysv/linux/spawni.c (maybe_script_execute):
Increment size of new_argv by one.
2018-09-05 Rafal Luzynski <digitalfreak@lingonborough.com>
[BZ #17426]

View File

@ -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)