mount: improve signal management when locking mtab

[nfs-utils.git] / utils / mount / fstab.c

diff --git a/utils/mount/fstab.c b/utils/mount/fstab.c
index a742e648d0e4d133c7e24eb07f2c4d591ad44cd5..1fc9efe8e24410152c171b5a279c6cbb077565fb 100644 (file)
--- a/utils/mount/fstab.c
+++ b/utils/mount/fstab.c
@@ -331,16 +331,43 @@ lock_mtab (void) {
                int sig = 0;
                struct sigaction sa;
 
-               sa.sa_handler = handler;
                sa.sa_flags = 0;
                sigfillset (&sa.sa_mask);
   
-               while (sigismember (&sa.sa_mask, ++sig) != -1
-                      && sig != SIGCHLD) {
-                       if (sig == SIGALRM)
+               while (sigismember (&sa.sa_mask, ++sig) != -1) {
+                       switch(sig) {
+                       case SIGCHLD:
+                       case SIGKILL:
+                       case SIGCONT:
+                       case SIGSTOP:
+                               /* The cannot be caught, or should not,
+                                * so don't even try.
+                                */
+                               continue;
+                       case SIGALRM:
                                sa.sa_handler = setlkw_timeout;
-                       else
+                               break;
+                       case SIGHUP:
+                       case SIGINT:
+                       case SIGQUIT:
+                       case SIGWINCH:
+                       case SIGTSTP:
+                       case SIGTTIN:
+                       case SIGTTOU:
+                       case SIGPIPE:
+                       case SIGXFSZ:
+                       case SIGXCPU:
+                               /* non-priv user can cause these to be
+                                * generated, so ignore them.
+                                */
+                               sa.sa_handler = SIG_IGN;
+                               break;
+                       default:
+                               /* The rest should not be possible, so just
+                                * print a message and unlock mtab.
+                                */
                                sa.sa_handler = handler;
+                       }
                        sigaction (sig, &sa, (struct sigaction *) 0);
                }
                signals_have_been_setup = 1;