fs: sysv: check sbi->s_firstdatazone in complete_read_super
sbi->s_firstinodezone is initialized to 2 and sbi->s_firstdatazone is read
from sbd. There's no guarantee that sbi->s_firstdatazone must bigger than
sbi->s_firstinodezone. If sbi->s_firstdatazone less than 2, the
filesystem can still be mounted unexpetly. At this point, sbi->s_ninodes
flip to very large value and this filesystem is broken. We can observe
this by executing 'df' command. When we execute, we will get an error
message:
"sysv_count_free_inodes: unable to read inode table"
Link: https://lkml.kernel.org/r/20220330104215.530223-1-liushixin2@huawei.com
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
1 file changed
