Bug 809280 - Memory leaks and crashers found in error-handling within libssh2-python-0.7.1-4.fc17 using gcc-with-cpychecker static analyzer
Summary: Memory leaks and crashers found in error-handling within libssh2-python-0.7.1...
Alias: None
Product: Fedora
Classification: Fedora
Component: libssh2-python
Version: 19
Hardware: Unspecified
OS: Unspecified
Target Milestone: ---
Assignee: Chris Lalancette
QA Contact: Fedora Extras Quality Assurance
URL: http://fedorapeople.org/~dmalcolm/gcc...
Depends On:
Blocks: cpychecker
TreeView+ depends on / blocked
Reported: 2012-04-02 23:50 UTC by Dave Malcolm
Modified: 2015-02-17 14:11 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Last Closed: 2015-02-17 14:11:28 UTC
Type: ---

Attachments (Terms of Use)

Description Dave Malcolm 2012-04-02 23:50:22 UTC
Description of problem:
I've been writing an experimental static analysis tool to detect bugs commonly occurring within C Python extension modules:

I ran the latest version of the tool (in git master; post 0.9) on
libssh2-python-0.7.1-4.fc17.src.rpm, and it reports various errors.

You can see a list of errors here, triaged into categories (from most significant to least significant):

I've manually reviewed the issues reported by the tool.

Within the category "Reference count too low" the 1 issue reported may or may not be a true error: I can't tell from the context

Within the category "Reference leaks" the 30 issues reported seem to stem from the CHECK_RETURN_CODE() macro: in particular, the RAISE_SSH2_ERROR() macro that it uses: in each case, each error-handling path has two reference leaks: that of _exc, and that of the Py_BuildValue result: both of these are built as new references, and nothing DECREFs them.  (Also, in each case the calls could fail)

Within the category "Reference count too low within an initialization routine" the 2 issues reported are likely to be inconsequential.

Within the category "Segfaults within error-handling paths" the 14 issues reported appear to be genuine crashers under low-memory conditions, where an earlier function call could return NULL, and nothing checks for it.  Many of these relate to the macros mentioned above.

There may of course be other bugs in my checker tool.

Hope this is helpful; let me know if you need help reading the logs that the tool generates - I know that it could use some improvement.

Version-Release number of selected component (if applicable):
gcc-python-plugin post-0.9 git d578ee0e46d93647d0f94502784f890c38139d60 running the checker in an *f16* chroot

Comment 1 Fedora End Of Life 2013-04-03 14:10:33 UTC
This bug appears to have been reported against 'rawhide' during the Fedora 19 development cycle.
Changing version to '19'.

(As we did not run this process for some time, it could affect also pre-Fedora 19 development
cycle bugs. We are very sorry. It will help us with cleanup during Fedora 19 End Of Life. Thank you.)

More information and reason for this action is here:

Comment 2 Fedora End Of Life 2015-01-09 17:05:30 UTC
This message is a notice that Fedora 19 is now at end of life. Fedora 
has stopped maintaining and issuing updates for Fedora 19. It is 
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longer maintained. Approximately 4 (four) weeks from now this bug will
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Comment 3 Fedora End Of Life 2015-02-17 14:11:28 UTC
Fedora 19 changed to end-of-life (EOL) status on 2015-01-06. Fedora 19 is
no longer maintained, which means that it will not receive any further
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