[XFS] Don't grow filesystems past the size they can index.
When growing a filesystem we don't check to see if the new size overflows
the page cache index range, so we can do silly things like grow a
filesystem page 16TB on a 32bit. Check new filesystem sizes against the
limits the kernel can support.
SGI-PV: 957886
SGI-Modid: xfs-linux-melb:xfs-kern:28563a
Signed-Off-By: Nathan Scott <nscott@aconex.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index a96bde6..5de1f39 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -202,6 +202,27 @@
kmem_free(mp, sizeof(xfs_mount_t));
}
+/*
+ * Check size of device based on the (data/realtime) block count.
+ * Note: this check is used by the growfs code as well as mount.
+ */
+int
+xfs_sb_validate_fsb_count(
+ xfs_sb_t *sbp,
+ __uint64_t nblocks)
+{
+ ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
+ ASSERT(sbp->sb_blocklog >= BBSHIFT);
+
+#if XFS_BIG_BLKNOS /* Limited by ULONG_MAX of page cache index */
+ if (nblocks >> (PAGE_CACHE_SHIFT - sbp->sb_blocklog) > ULONG_MAX)
+ return E2BIG;
+#else /* Limited by UINT_MAX of sectors */
+ if (nblocks << (sbp->sb_blocklog - BBSHIFT) > UINT_MAX)
+ return E2BIG;
+#endif
+ return 0;
+}
/*
* Check the validity of the SB found.
@@ -284,18 +305,8 @@
return XFS_ERROR(EFSCORRUPTED);
}
- ASSERT(PAGE_SHIFT >= sbp->sb_blocklog);
- ASSERT(sbp->sb_blocklog >= BBSHIFT);
-
-#if XFS_BIG_BLKNOS /* Limited by ULONG_MAX of page cache index */
- if (unlikely(
- (sbp->sb_dblocks >> (PAGE_SHIFT - sbp->sb_blocklog)) > ULONG_MAX ||
- (sbp->sb_rblocks >> (PAGE_SHIFT - sbp->sb_blocklog)) > ULONG_MAX)) {
-#else /* Limited by UINT_MAX of sectors */
- if (unlikely(
- (sbp->sb_dblocks << (sbp->sb_blocklog - BBSHIFT)) > UINT_MAX ||
- (sbp->sb_rblocks << (sbp->sb_blocklog - BBSHIFT)) > UINT_MAX)) {
-#endif
+ if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) ||
+ xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) {
xfs_fs_mount_cmn_err(flags,
"file system too large to be mounted on this system.");
return XFS_ERROR(E2BIG);