diff options
Diffstat (limited to 'src/launch.c')
| -rw-r--r-- | src/launch.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/src/launch.c b/src/launch.c index 1dc23f40..1b496f69 100644 --- a/src/launch.c +++ b/src/launch.c @@ -844,9 +844,34 @@ launch_appliance (guestfs_h *g) if (g->recovery_proc) { r = fork (); if (r == 0) { + int i, fd, max_fd; + struct sigaction sa; pid_t qemu_pid = g->pid; pid_t parent_pid = getppid (); + /* Remove all signal handlers. See the justification here: + * https://www.redhat.com/archives/libvir-list/2008-August/msg00303.html + * We don't mask signal handlers yet, so this isn't completely + * race-free, but better than not doing it at all. + */ + memset (&sa, 0, sizeof sa); + sa.sa_handler = SIG_DFL; + sa.sa_flags = 0; + sigemptyset (&sa.sa_mask); + for (i = 1; i < NSIG; ++i) + sigaction (i, &sa, NULL); + + /* Close all other file descriptors. This ensures that we don't + * hold open (eg) pipes from the parent process. + */ + max_fd = sysconf (_SC_OPEN_MAX); + if (max_fd == -1) + max_fd = 1024; + if (max_fd > 65536) + max_fd = 65536; /* bound the amount of work we do here */ + for (fd = 0; fd < max_fd; ++fd) + close (fd); + /* It would be nice to be able to put this in the same process * group as qemu (ie. setpgid (0, qemu_pid)). However this is * not possible because we don't have any guarantee here that |