[PATCH] sftp: fix connection memleaks

[and]

1) open_connection abort not handled correct yet
2) missing libssh2_session_free() on close_connection
3) internal list from libssh2_userauth_list() must not freed by mc
4) cosmetic: re-order open_connection and close_connection steps
5) cosmetic: sftpfs_super_data created at sftpfs_cb_open_connection() was freed at sftpfs_close_connection()

it should be sftpfs_cb_close_connection() for logical right location

6) add FIXME for deprected libssh2_session_startup() since libssh2 1.2.8

found by Clang/AddressSanitizer?

[andrew_b]

Is it possible to split this patch into several ones with independent issues?

[and]

sure, I will do so.

[andrew_b]

Thanks!

Branch: 3581_sftp_fixes
Initial changeset:fa4056b405a47935aa9fd21370d0d0fe92b41d7a

[zaytsev]

Hi Andreas,

Maybe you will find it interesting to have a look at this Debian bug, which also has to do with SFTP:

​https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=774135

So, in essence, the user is running Debian x32 (!) and there SFTP is completely broken. Probably this happens due to some type size weirdness on x32, because we can't reproduce it on i386 and amd64.

--Yury

[andrew_b]

Replying to zaytsev:

​https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=774135

So, in essence, the user is running Debian x32 (!) and there SFTP is completely broken. Probably this happens due to some type size weirdness on x32, because we can't reproduce it on i386 and amd64.

I've added fix of config file reading. I don't think that it fixes that bug, but who knows.

[zaytsev]

Some new info from the Debian bug, with 4.8.15 it looks like this:

$ touch .ssh/config
$ mc
$ cd /sftp://localhost

╔═════════════════════════════════════════ Error ═════════════════════════════════════════╗
║                                                                                         ║
║ 25: sftp: an error occurred while reading ~/.ssh/config: Inappropriate ioctl for device ║
║                                                                                         ║
╚═════════════════════════════════════════════════════════════════════════════════════════╝

╔═══════════════ Error ════════════════╗
║                                      ║
║ Cannot chdir to "/sftp://localhost/" ║
║           File exists (17)           ║
║                                      ║
╚══════════════════════════════════════╝

Asked to test with the latest 3581_sftp_fixes branch...

[and]

Can Thorsten test following patch?

when reading ssh_config with matching host entry mc do bad pointer arithmetic

[andrew_b]

Ticket #3590 has been marked as a duplicate of this ticket.

[andrew_b]

Merged to master: [ab0c2afba5a142c6091bd40d913c75f4669f1280].

git log --pretty=oneline 9dcf033..ab0c2af