Re: [PATCH 2/3] Fix Wunused-return warnings

On Friday, February 08, 2013 07:12:34 PM Tyler Hicks wrote: > When building with -D_FORTIFY_SOURCE=2 and -W-unused-return, there are a > number of warnings caused by return values of functions marked with the > warn_unused_result attribute being ignored. The audit codebase makes an > attempt to suppress these warnings by casting the return value to void, but > that does not work when D_FORITY_SOURCE is in use. > > Here's an explanation of how this patch fixes the warnings and how the > potential error conditions are handled: > > Errors writing to the auditd pid file should be logged since errors opening > the pid file are logged. These write() errors aren't treated as fatal. > > Problems adjusting auditd's out of memory score should be logged, if simply > to catch a change to the kernel interface. These errors aren't treated as > fatal. > > Auditd refuses to start when nice() fails during initialization, so it > should take disk_error_action whenever nice() fails during a reconfigure. During a reconfigure, I would not consider this fatal. Its better to stay running than exit. I'll adjust the patch.

-Steve > Failure to chdir("/") while daemonizing should be logged and treated as > fatal since errors while redirecting stdin, stdout, and stderr are logged > and considered fatal. > > All nice() return values are handled sufficiently by relying on errno. > However, they still throw warnings when D_FORTIFY_SOURCE is used. This patch > quiets those warnings by capturing the return value and using it and errno > to determine if nice() failed. > > Failure to adjust audit log file owner (fchown) and permissions (fchmod) are > logged and considered fatal when opening the log file for the first time. > They are not treated as fatal when the operations fail on during log > rotation since we made sure that they file owner and permissions were > correct when originally opening the log file.