Fix problems with array.size overflowing on large arrays.

array.size is 32bits and counts K.  So for arrays with
more than 4Terrabytes, it can overflow.
The correct number can be read from sysfs, but there are still
a few places that use array.size and risk truncation.  What is worse.
they compare a number of kilobytes with a number of sectors !!

So use get_component_size() to read the sysfs information, and be
more consistent about units.

diff --git a/ChangeLog b/ChangeLog
index fdf720d24cacf2d8b057314c596184c4c2b715e6..fd42b4e1ea69ce7a3c3f9e78c8ccf0997527f056 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,8 @@
 Changes Prior to this release
     -   Avoid segfault when parsing /proc/mdstat with auto-read-only
        arrays.
+    -   Fix problem with failing to add devices to v.large (>4TB) arrays,
+       cause by problems with device-size overflow.
 
 Changes Prior to 2.6.4 release
     -   Make "--create --auto=mdp" work for non-standard device names.

diff --git a/Detail.c b/Detail.c
index de1f409e8fe8498fc100e963f42f30a7c0095b1c..6199d26fc5617793794776f1987cdbd000e7c99a 100644 (file)
--- a/Detail.c
+++ b/Detail.c
@@ -191,7 +191,7 @@ int Detail(char *dev, int brief, int export, int test, char *homehost)
                                if (dsize > 0)
                                        printf("  Used Dev Size : %llu%s\n",
                                               dsize,
-                                        human_size((long long)array.size<<10));
+                                        human_size((long long)dsize<<10));
                                else
                                        printf("  Used Dev Size : unknown\n");
                        } else

diff --git a/Manage.c b/Manage.c
index f17105a85202ff14092494d646246c9229f2c31c..1fb8468981886342d76f9786a8ff90a203f27c47 100644 (file)
--- a/Manage.c
+++ b/Manage.c
@@ -188,6 +188,7 @@ int Manage_subdevs(char *devname, int fd,
         */
        mdu_array_info_t array;
        mdu_disk_info_t disc;
+       unsigned long long array_size;
        mddev_dev_t dv, next = NULL;
        struct stat stb;
        int j, jnext = 0;
@@ -202,6 +203,14 @@ int Manage_subdevs(char *devname, int fd,
                return 1;
        }
 
+       /* array.size is only 32 bit and may be truncated.
+        * So read from sysfs if possible, and record number of sectors
+        */
+
+       array_size = get_component_size(fd);
+       if (array_size <= 0)
+               array_size = array.size * 2;
+
        tst = super_by_fd(fd);
        if (!tst) {
                fprintf(stderr, Name ": unsupport array - version %d.%d\n",
@@ -337,7 +346,7 @@ int Manage_subdevs(char *devname, int fd,
 
                                /* Make sure device is large enough */
                                if (tst->ss->avail_size(tst, ldsize/512) <
-                                   array.size) {
+                                   array_size) {
                                        fprintf(stderr, Name ": %s not large enough to join array\n",
                                                dv->devname);
                                        return 1;
@@ -412,7 +421,7 @@ int Manage_subdevs(char *devname, int fd,
                                /* non-persistent. Must ensure that new drive
                                 * is at least array.size big.
                                 */
-                               if (ldsize/512 < array.size) {
+                               if (ldsize/512 < array_size) {
                                        fprintf(stderr, Name ": %s not large enough to join array\n",
                                                dv->devname);
                                        return 1;