e2fsck: fix hang in readahead code if last block in fs is metadata

If the last block the file system is metadata (very rare, but it can
happen, especially if e2fsck needs to relocate a bitmap block), e2fsck
will hang while trying to do readahead.

This problem was reported by Adam Buchbinder.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/e2fsck/readahead.c b/e2fsck/readahead.c
index a860f2b..38d4ec4 100644 (file)
--- a/e2fsck/readahead.c
+++ b/e2fsck/readahead.c
@@ -98,6 +98,8 @@ static errcode_t e2fsck_readahead_bitmap(ext2_filsys fs,
                if (err == ENOENT) {
                        out = end;
                        err = 0;
+                       if (out == start)
+                               break;
                } else if (err)
                        break;