2009-10-25 Robert Millan <rmh.grub@aybabtu.com>

* include/grub/fs.h [GRUB_UTIL] (struct grub_fs): Add
        `reserved_first_sector' member.
        * fs/ext2.c [GRUB_UTIL] (grub_ext2_fs): Initialize
        `reserved_first_sector' to 1.
        * fs/fat.c [GRUB_UTIL] (grub_fat_fs): Likewise.
        * fs/ntfs.c [GRUB_UTIL] (grub_ntfs_fs): Likewise.
        * fs/hfsplus.c [GRUB_UTIL] (grub_hfsplus_fs): Likewise.
        * util/i386/pc/grub-setup.c (setup): Add safety check that probes for
        filesystems which begin at first sector.
        (options): New option --skip-fs-probe.   
        (main): Handle --skip-fs-probe and pass it to setup().

ChangeLog

@@ -1,3 +1,17 @@
+2009-10-25  Robert Millan  <rmh.grub@aybabtu.com>
+
+	* include/grub/fs.h [GRUB_UTIL] (struct grub_fs): Add
+	`reserved_first_sector' member.
+	* fs/ext2.c [GRUB_UTIL] (grub_ext2_fs): Initialize
+	`reserved_first_sector' to 1.
+	* fs/fat.c [GRUB_UTIL] (grub_fat_fs): Likewise.
+	* fs/ntfs.c [GRUB_UTIL] (grub_ntfs_fs): Likewise.
+	* fs/hfsplus.c [GRUB_UTIL] (grub_hfsplus_fs): Likewise.
+	* util/i386/pc/grub-setup.c (setup): Add safety check that probes for
+	filesystems which begin at first sector.
+	(options): New option --skip-fs-probe.
+	(main): Handle --skip-fs-probe and pass it to setup().
+
 2009-10-25  Robert Millan  <rmh.grub@aybabtu.com>
 
 	* include/grub/misc.h: Fix wrong evaluation of APPLE_CC.

fs/ext2.c

@@ -927,6 +927,9 @@ static struct grub_fs grub_ext2_fs =
     .label = grub_ext2_label,
     .uuid = grub_ext2_uuid,
     .mtime = grub_ext2_mtime,
+#ifdef GRUB_UTIL
+    .reserved_first_sector = 1,
+#endif
     .next = 0
   };
 

fs/fat.c

@@ -855,6 +855,9 @@ static struct grub_fs grub_fat_fs =
     .close = grub_fat_close,
     .label = grub_fat_label,
     .uuid = grub_fat_uuid,
+#ifdef GRUB_UTIL
+    .reserved_first_sector = 1,
+#endif
     .next = 0
   };
 

fs/hfsplus.c

@@ -1021,6 +1021,9 @@ static struct grub_fs grub_hfsplus_fs =
     .label = grub_hfsplus_label,
     .mtime = grub_hfsplus_mtime,
     .uuid = grub_hfsplus_uuid,
+#ifdef GRUB_UTIL
+    .reserved_first_sector = 1,
+#endif
     .next = 0
   };
 

fs/ntfs.c

@@ -1081,15 +1081,19 @@ grub_ntfs_uuid (grub_device_t device, char **uuid)
   return grub_errno;
 }
 
-static struct grub_fs grub_ntfs_fs = {
-  .name = "ntfs",
-  .dir = grub_ntfs_dir,
-  .open = grub_ntfs_open,
-  .read = grub_ntfs_read,
-  .close = grub_ntfs_close,
-  .label = grub_ntfs_label,
-  .uuid = grub_ntfs_uuid,
-  .next = 0
+static struct grub_fs grub_ntfs_fs =
+  {
+    .name = "ntfs",
+    .dir = grub_ntfs_dir,
+    .open = grub_ntfs_open,
+    .read = grub_ntfs_read,
+    .close = grub_ntfs_close,
+    .label = grub_ntfs_label,
+    .uuid = grub_ntfs_uuid,
+#ifdef GRUB_UTIL
+    .reserved_first_sector = 1,
+#endif
+    .next = 0
 };
 
 GRUB_MOD_INIT (ntfs)

include/grub/fs.h

@@ -68,6 +68,11 @@ struct grub_fs
   /* Get writing time of filesystem. */
   grub_err_t (*mtime) (grub_device_t device, grub_int32_t *timebuf);
 
+#ifdef GRUB_UTIL
+  /* Whether this filesystem reserves first sector for DOS-style boot.  */
+  int reserved_first_sector;
+#endif
+
   /* The next filesystem.  */
   struct grub_fs *next;
 };

util/i386/pc/grub-setup.c

@@ -86,7 +86,7 @@ grub_refresh (void)
 static void
 setup (const char *dir,
        const char *boot_file, const char *core_file,
-       const char *root, const char *dest, int must_embed, int force)
+       const char *root, const char *dest, int must_embed, int force, int fs_probe)
 {
   char *boot_path, *core_path, *core_path_dev;
   char *boot_img, *core_img;
@@ -251,6 +251,21 @@ setup (const char *dir,
   if (grub_disk_read (dest_dev->disk, 0, 0, GRUB_DISK_SECTOR_SIZE, tmp_img))
     grub_util_error ("%s", grub_errmsg);
 
+  if (dest_dev->disk->partition && fs_probe)
+    {
+      grub_fs_t fs;
+      fs = grub_fs_probe (dest_dev);
+      if (! fs)
+	grub_util_error ("Unable to identify a filesystem in %s; safety check can't be performed.");
+
+      if (! fs->reserved_first_sector)
+	grub_util_error ("%s appears to contain a %s filesystem which isn't known to "
+			 "reserve space for DOS-style boot.  Installing GRUB there could "
+			 "result in FILESYSTEM DESTRUCTION if valuable data is overwritten "
+			 "by grub-setup (--skip-fs-probe disables this "
+			 "check, use at your own risk).", dest_dev->disk->name, fs->name);
+    }
+
   /* Copy the possible DOS BPB.  */
   memcpy (boot_img + GRUB_BOOT_MACHINE_BPB_START,
 	  tmp_img + GRUB_BOOT_MACHINE_BPB_START,
@@ -556,6 +571,7 @@ static struct option options[] =
     {"device-map", required_argument, 0, 'm'},
     {"root-device", required_argument, 0, 'r'},
     {"force", no_argument, 0, 'f'},
+    {"skip-fs-probe", no_argument, 0, 's'},
     {"help", no_argument, 0, 'h'},
     {"version", no_argument, 0, 'V'},
     {"verbose", no_argument, 0, 'v'},
@@ -580,6 +596,7 @@ DEVICE must be a GRUB device (e.g. ``(hd0,1)'').\n\
   -m, --device-map=FILE   use FILE as the device map [default=%s]\n\
   -r, --root-device=DEV   use DEV as the root device [default=guessed]\n\
   -f, --force             install even if problems are detected\n\
+  -s, --skip-fs-probe     do not probe for filesystems in DEVICE\n\
   -h, --help              display this message and exit\n\
   -V, --version           print version information and exit\n\
   -v, --verbose           print verbose messages\n\
@@ -613,7 +630,7 @@ main (int argc, char *argv[])
   char *dev_map = 0;
   char *root_dev = 0;
   char *dest_dev;
-  int must_embed = 0, force = 0;
+  int must_embed = 0, force = 0, fs_probe = 1;
 
   progname = "grub-setup";
 
@@ -666,6 +683,10 @@ main (int argc, char *argv[])
 	    force = 1;
 	    break;
 
+	  case 's':
+	    fs_probe = 0;
+	    break;
+
 	  case 'h':
 	    usage (0);
 	    break;
@@ -767,7 +788,7 @@ main (int argc, char *argv[])
 	  setup (dir ? : DEFAULT_DIRECTORY,
 		 boot_file ? : DEFAULT_BOOT_FILE,
 		 core_file ? : DEFAULT_CORE_FILE,
-		 root_dev, grub_util_get_grub_dev (devicelist[i]), 1, force);
+		 root_dev, grub_util_get_grub_dev (devicelist[i]), 1, force, fs_probe);
 	}
     }
   else
@@ -776,7 +797,7 @@ main (int argc, char *argv[])
     setup (dir ? : DEFAULT_DIRECTORY,
 	   boot_file ? : DEFAULT_BOOT_FILE,
 	   core_file ? : DEFAULT_CORE_FILE,
-	   root_dev, dest_dev, must_embed, force);
+	   root_dev, dest_dev, must_embed, force, fs_probe);
 
   /* Free resources.  */
   grub_fini_all ();