radiusd: Cannot change ownership of log file /tmp/test.log: Operation not permitted

[spbnick]

Issue type

• Defect - Crash or memory corruption.
• Defect - Non compliance with a standards document, or incorrect API usage.
• Defect - Unexpected behaviour (obvious or verified by project member).
• Feature request.

Defect/Feature description

Radiusd (latest v3.0.x) fails to log to a file supplied with -l option, producing the following message:

radiusd: Cannot change ownership of log file /tmp/test.log: Operation not permitted

strace shows what's happening:

setgroups(1, [95])                      = 0
setgid(95)                              = 0
mkdir("/var/log/radius", 0700)          = -1 EEXIST (File exists)
geteuid()                               = 0
setresuid(4294967295, 95, 0)            = 0
geteuid()                               = 95
setrlimit(RLIMIT_CORE, {rlim_cur=0, rlim_max=0}) = 0
fchown(3, 95, 95)                       = -1 EPERM (Operation not permitted)

See also https://bugzilla.redhat.com/show_bug.cgi?id=1421207

How to reproduce issue

sudo radiusd -sfxx -l /tmp/test.log

[spbnick]

Thanks, Alan!