ufs: validate maximum fast symlink size from superblock

The maximum fast symlink size is set in the superblock of certain types
of UFS filesystem. Before using it we need to check that it isn't longer
than the available space we have in the inode.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Duane Griffin 2009-01-08 22:43:48 +00:00 committed by Al Viro
parent c8fe8f30c7
commit 9e6766cc8c

View File

@ -636,6 +636,7 @@ static int ufs_fill_super(struct super_block *sb, void *data, int silent)
unsigned block_size, super_block_size;
unsigned flags;
unsigned super_block_offset;
unsigned maxsymlen;
int ret = -EINVAL;
uspi = NULL;
@ -1069,6 +1070,16 @@ magic_found:
uspi->s_maxsymlinklen =
fs32_to_cpu(sb, usb3->fs_un2.fs_44.fs_maxsymlinklen);
if (uspi->fs_magic == UFS2_MAGIC)
maxsymlen = 2 * 4 * (UFS_NDADDR + UFS_NINDIR);
else
maxsymlen = 4 * (UFS_NDADDR + UFS_NINDIR);
if (uspi->s_maxsymlinklen > maxsymlen) {
ufs_warning(sb, __func__, "ufs_read_super: excessive maximum "
"fast symlink size (%u)\n", uspi->s_maxsymlinklen);
uspi->s_maxsymlinklen = maxsymlen;
}
inode = ufs_iget(sb, UFS_ROOTINO);
if (IS_ERR(inode)) {
ret = PTR_ERR(inode);