Test for holes in swapfiles

 -Erik


git-svn-id: svn://busybox.net/trunk/busybox@5779 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 12 insertions, 0 deletions

diff --git a/util-linux/swaponoff.c b/util-linux/swaponoff.c
index a57dfe472..918a5bc0e 100644
--- a/util-linux/swaponoff.c
+++ b/util-linux/swaponoff.c
@@ -48,6 +48,18 @@ static const int SWAPOFF_APP = 1;
 static int swap_enable_disable(const char *device)
 {
         int status;
+        struct stat st;
+
+        if (stat(device, &st) < 0) {
+                perror_msg_and_die("cannot stat %s");
+        }
+
+        /* test for holes */
+        if (S_ISREG(st.st_mode)) {
+                if (st.st_blocks * 512 < st.st_size) {
+                        error_msg_and_die("swap file has holes");
+                }
+        }
 
         if (whichApp == SWAPON_APP)
                 status = swapon(device, 0);