Re: [PATCH 4.4 095/105] udf: Detect incorrect directory size

On Sun, 2018-07-01 at 18:02 +0200, Greg Kroah-Hartman wrote:

4.4-stable review patch.  If anyone has any objections, please let me know.

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From: Jan Kara jack@suse.cz

commit fa65653e575fbd958bdf5fb9c4a71a324e39510d upstream.

Detect when a directory entry is (possibly partially) beyond directory size and return EIO in that case since it means the filesystem is corrupted. Otherwise directory operations can further corrupt the directory and possibly also oops the kernel.

[...]

--- a/fs/udf/directory.c +++ b/fs/udf/directory.c @@ -150,6 +150,9 @@ struct fileIdentDesc *udf_fileident_read          sizeof(struct fileIdentDesc));   }   }

• /* Got last entry outside of dir size - fs is corrupted! */
• if (*nf_pos > dir->i_size)

• return NULL;
  

return fi;  }

Is the same check needed when iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB?

Ben.