Bug#449513: axel: crashes when a HTTP 302 redirects it to a FTP location

Sun, 29 May 2016 16:12:46 -0700 

Control: found 449513 2.7-1

Hi,

Currently, it can be reproduced using:

$ axel 
http://ftp.linux.ncsu.edu/pub/CentOS/7.2.1511/isos/x86_64/CentOS-7-x86_64-DVD-1511.iso

I attached a tcpdump capture made with Axel 2.7-1. (to reproduct, #
tcpdump -n host ftp.linux.ncsu.edu -A; to read the attached file #
tcpdumpp -nr <file> -A)

The attached file is ftp.linux.ncsu.edu-2.pcap.gz

I can see the following sequence:

1. The tcpdump shows the redirection from http://ftp.linux.ncsu.edu to
ftp://ftp.linux.ncsu.edu (HTTP/1.1 301 Moved Permanently).

2. The server sents a FIN and Axel sents a ACK followed by a RST.

3. A new connection from Axel to ftp://ftp.linux.ncsu.edu. Client port
41350. The traffic:

server> _AE220 Welcome to NC State Red Hat Linux and Realm Linux mirror.
client> USER anonymous
server> _Ax331 Please specify the password.
client> PASS mailto:axel@axel.project
server> _A.230 Login successful
client> TYPE I
server> _A.200 Switching to Binary mode
client> CWD //pub/CentOS/7.2.1511/isos/x86_64/
server> _B.250 Directory successfully changed
client> PASV
server> _BB227 Entering Passive Mode (152,1,2,172,255,65)

4. A new connection from Axel without close the last connection. Port 60908:

client> REST 1
server> _B.350 Restart position accepted (1)
client> RETR CentOS-7-x86_64-DVD-1511.iso
server> _B.150 Opening BINARY mode data connection for
CentOS-7-x86_64-DVD-1511.iso (4329570304 bytes)
client> FIN (port 41350)
client> FIN (port 60908)
server> data sent to port 60908
client> RST

5. A new connection from Axel. Port 41352:

server> Still sending data to 60908
client> RST
server> Still sending data to 60908
client> RST
server> Still sending data to 60908 (TCP sliding window?)
client> RST
server> Still sending data to 60908
client> RST
server> Still sending data to 60908
client> RST
[...]
server> _C^220 Welcome to NC State Red Hat Linux and Realm Linux
mirror. (to 41352)
client> USER anonymous (41352)
server> _C.331 Please specify the password
client> PASS mailto:axel@axel.project
server> Still sending data to 60908
client> RST
server> _C.230 Login successful (41352)
client> TYPE I
server> _C.200 Switching to Binary mode
client> CWD //pub/CentOS/7.2.1511/isos/x86_64/
server> 250 Directory successfully changed
client> PASV
server> _BB227 Entering Passive Mode (152,1,2,172,23,196)

6. A new connection from Axel (port 43218)

client> REST 1 (from 41352)
server> 350 Restart position accepted (1) (to 41352)
client> RETR CentOS-7-x86_64-DVD-1511.iso (41352)
server> 150 Opening BINARY mode data connection for
CentOS-7-x86_64-DVD-1511.iso (4329570304 bytes) (41352)
client> FIN (from 41352)
client> FIN (from 43218)
server> data to 43218
client> RST (from 43218)

7. A new connection from Axel (port 41354)

server> data to 43218
client> RST

[similar traffic will occur several times]

8. After several connections, resets and events:

server> 426 Failure writing network stream (to 41356)
client> RST
server> 8500 OOPS
client> RST
server> vsf_sysutil_recv_peek: no data
client> RST
server> anything to client (PSH)
client> RST
server> 8500 OOPS
client> RST
server> child died
client> RST
server> anything to client (PSH)
client> RST
server> FIN
client> RST
server> 8426 Failure writing network stream
client> RST
server> 8426 Failure writing network stream
client> RST

9. Following, a traffic from server to client port 34421:

server> data to client
client> RST
server> 8426 Failure writing network stream
client> RST

10. Server to 41356:

server> 8426 Failure writing network stream
client> RST

11. Server to client 43218:

server> data
client> RST

12. server to client 34421:

server> data
client> RST

13. server to client 41356:

server> 8426 Failure writing network stream
client> RST
server> 8426 Failure writing network stream
client> RST


------------------------------

Trying a limited conection:

$ axel -n 1 
http://ftp.linux.ncsu.edu/pub/CentOS/7.2.1511/isos/x86_64/CentOS-7-x86_64-DVD-1511.iso

Segmentation fault

The traffic is very similar: several resets etc. I attached this file:
ftp.linux.ncsu.edu-3.pcap.gz

---------------------------------

New tests:

1. A test with wget do a download with perfection.

2. The 
http://ftp.linux.ncsu.edu/pub/CentOS/7.2.1511/isos/x86_64/CentOS-7-x86_64-DVD-1511.iso
is redirected to
http://ftp.linux.ncsu.edu/pub/CentOS/7.2.1511/isos/x86_64/CentOS-7-x86_64-DVD-1511.iso,
as seem.

I a new test, the following command works fine:

$ axel 
ftp://ftp.linux.ncsu.edu/pub/CentOS/7.2.1511/isos/x86_64/CentOS-7-x86_64-DVD-1511.iso

So, confirmed: the redirection from HTTP to FTP is broken.

Eriberto

Attachment: ftp.linux.ncsu.edu-2.pcap.gz
Description: GNU Zip compressed data

Attachment: ftp.linux.ncsu.edu-3.pcap.gz
Description: GNU Zip compressed data

Reply via email to