qemu-sockets: do not test path with access() before unlinking

Using access() is a time-of-check/time-of-use race condition.  It is
okay to use them to provide better error messages, but that is pretty
much it.

This is not one such case; on the other hand, access() *will* skip
unlink() for a non-existent path, so ignore ENOENT return values from
the unlink() system call.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
This commit is contained in:
Paolo Bonzini 2015-11-04 14:48:47 +01:00 committed by Michael Tokarev
parent 3ede8f6996
commit a2f31f1804

View file

@ -751,8 +751,7 @@ int unix_listen_opts(QemuOpts *opts, Error **errp)
qemu_opt_set(opts, "path", un.sun_path, &error_abort);
}
if ((access(un.sun_path, F_OK) == 0) &&
unlink(un.sun_path) < 0) {
if (unlink(un.sun_path) < 0 && errno != ENOENT) {
error_setg_errno(errp, errno,
"Failed to unlink socket %s", un.sun_path);
goto err;