From a2f31f180499593b5edb8ac5ab8ac1b92f0abcd4 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 4 Nov 2015 14:48:47 +0100 Subject: [PATCH] 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 Reviewed-by: Markus Armbruster Reviewed-by: Edgar E. Iglesias Signed-off-by: Michael Tokarev --- util/qemu-sockets.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/util/qemu-sockets.c b/util/qemu-sockets.c index dfe45875f8..5a31d164d9 100644 --- a/util/qemu-sockets.c +++ b/util/qemu-sockets.c @@ -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; -- 2.11.4.GIT