16 Nov
2021
16 Nov
'21
1:36 p.m.
On Tue, Nov 16, 2021 at 09:30:12AM +0000, David Laight wrote:
From: Alistair Delva
Sent: 15 November 2021 19:09
...
if (!capable(CAP_SYS_NICE) && !capable(CAP_SYS_ADMIN))
if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_NICE)) return -EPERM;Isn't the real problem that you actually want to test: if (!capable(CAP_SYS_NICE | CAP_SYS_ADMIN)) return -EPERM; so that you only get the fail 'splat' when neither is set.
This will be true whenever more than one capability enables something.
Possibly this needs something like: int capabale_or(unsigned int, ...); #define capabale_or(...) capabable_or(__VA_LIST__, ~0u)
David
Right, that's what i was suggesting yesterday. We do this in other places, where we split off a more fine-grained version of a gross capability. If we care enough about the audit messages, then we probably do need a new primitive.
-serge