V7: Adjust sanity checks for some volumes

Newly mkfs-ed filesystems from Seventh Edition have last modification
time set to zero, but are otherwise perfectly valid.

Also, tighten up other sanity checks to filter out most filesystems with
different bytesex than we're using.

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/sysv/super.c b/fs/sysv/super.c
index 2da3075aff78..5c0aab0b7e18 100644
--- a/fs/sysv/super.c
+++ b/fs/sysv/super.c
@@ -469,7 +469,7 @@ static int v7_fill_super(struct super_block *sb, void *data, int silent)
         v7sb = (struct v7_super_block *) bh->b_data;
         if (fs16_to_cpu(sbi, v7sb->s_nfree) > V7_NICFREE ||
             fs16_to_cpu(sbi, v7sb->s_ninode) > V7_NICINOD ||
-            fs32_to_cpu(sbi, v7sb->s_time) == 0)
+            fs32_to_cpu(sbi, v7sb->s_fsize) > V7_MAXSIZE)
                 goto failed;
 
         /* plausibility check on root inode: it is a directory,
@@ -479,7 +479,9 @@ static int v7_fill_super(struct super_block *sb, void *data, int silent)
         v7i = (struct sysv_inode *)(bh2->b_data + 64);
         if ((fs16_to_cpu(sbi, v7i->i_mode) & ~0777) != S_IFDIR ||
             (fs32_to_cpu(sbi, v7i->i_size) == 0) ||
-            (fs32_to_cpu(sbi, v7i->i_size) & 017) != 0)
+            (fs32_to_cpu(sbi, v7i->i_size) & 017) ||
+            (fs32_to_cpu(sbi, v7i->i_size) > V7_NFILES *
+             sizeof (struct sysv_dir_entry)))
                 goto failed;
         brelse(bh2);
         bh2 = NULL;