[bug-mailutils] qp_decode and base64_decode

[Shashank Kavishwar]

filter_trans.c seems to be having problems in the 2 functions qp_decode and base64_decode

 

1. qp_decode:

message_save_attachment() does not return if a MIME message has a body of quoted-printable encoding which has a long series of spaces/HT's such that the following condition is satisfied in qp_decode(): wscount==consumed.

 

filter_trans.c =~ line 392

 

            while (consumed < isize && *nbytes < osize) {

            }

 

While the above condition is satisfied, if iptr only consists of spaces/HT's, 0 will be returned indefinitely.

E.g. calling message_save_attachment() with the attached file 'qp_problem.txt', does not return.

 

 

2. base64_decode:

message_save_attachment() does not return if a MIME message has a mistaken body of plain 7bit text instead of base64 encoded text.

The variable 'pad' keeps on increasing (quite frequent in HTML text which has the '=' quite frequently), and once pad crosses '3', *nbytes will start decreasing, ultimately resulting in a negative *nbytes value which loops indefinitely.

E.g. calling message_save_attachment() with the attached file 'base64_problem.txt', does not return.

qp_problem.txt
Description: Text document

base64_problem.txt
Description: Text document