bfs: check that filesystem fits on the blockdevice
Since all sanity checks rely on the validity of s_start which gets only
checked to be smaller than s_end, we should also check if s_end is sane.
Now we also try to retrieve the last block of the filesystem, which is
computed by s_end. If this fails, something is bogus.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Acked-by: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
index 1d2bfaf..cc4062d 100644
--- a/fs/bfs/inode.c
+++ b/fs/bfs/inode.c
@@ -390,6 +390,18 @@
- le32_to_cpu(bfs_sb->s_start)) >> BFS_BSIZE_BITS;
info->si_freei = 0;
info->si_lf_eblk = 0;
+
+ /* can we read the last block? */
+ bh = sb_bread(s, info->si_blocks - 1);
+ if (!bh) {
+ printf("Last block not available: %lu\n", info->si_blocks - 1);
+ iput(inode);
+ ret = -EIO;
+ kfree(info->si_imap);
+ goto out;
+ }
+ brelse(bh);
+
bh = NULL;
for (i = BFS_ROOT_INO; i <= info->si_lasti; i++) {
struct bfs_inode *di;