Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1235444

Re: [PATCH v2] capabilities.7, prctl.2: Document ambient capabilities

From Kees Cook <keescook@chromium.org>
Newsgroups linux.kernel
Subject Re: [PATCH v2] capabilities.7, prctl.2: Document ambient capabilities
Date 2015-09-29 20:00 +0200
Message-ID <qe7m2-5cj-15@gated-at.bofh.it> (permalink)
References <qdRAB-831-1@gated-at.bofh.it> <qe7cn-50W-21@gated-at.bofh.it> <qe7m2-5cj-5@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Tue, Sep 29, 2015 at 10:49 AM, Andy Lutomirski <luto@amacapital.net> wrote:
> On Tue, Sep 29, 2015 at 10:47 AM, Kees Cook <keescook@chromium.org> wrote:
>> On Mon, Sep 28, 2015 at 6:03 PM, Andy Lutomirski <luto@kernel.org> wrote:
>>> Signed-off-by: Andy Lutomirski <luto@kernel.org>
>>> ---
>>>  man2/prctl.2        | 12 ++++++++++++
>>>  man7/capabilities.7 | 40 ++++++++++++++++++++++++++++++++++------
>>>  2 files changed, 46 insertions(+), 6 deletions(-)
>>>
>>> diff --git a/man2/prctl.2 b/man2/prctl.2
>>> index e743a6305969..5bcec391c110 100644
>>> --- a/man2/prctl.2
>>> +++ b/man2/prctl.2
>>> @@ -954,6 +954,18 @@ had been called.
>>>  For further information on Intel MPX, see the kernel source file
>>>  .IR Documentation/x86/intel_mpx.txt .
>>>  .\"
>>> +.TP
>>> +.BR PR_CAP_AMBIENT " (since Linux 4.2)"
>>> +Reads or changes the ambient capability set.  If arg2 is PR_CAP_AMBIENT_RAISE,
>>> +then the capability specified in arg3 is added to the ambient set.  This will
>>> +fail, returning EPERM, if the capability is not already both permitted and
>>> +inheritable or if the SECBIT_NO_CAP_AMBIENT_RAISE securebit is set.  If arg2
>>> +is PR_CAP_AMBIENT_LOWER, then the capability specified in arg3 is removed
>>> +from the ambient set.  If arg2 is PR_CAP_AMBIENT_IS_SET, then
>>> +.BR prctl (2)
>>> +will return 1 if the capability in arg3 is in the ambient set and 0 if not.
>>> +If arg2 is PR_CAP_AMBIENT_CLEAR_ALL, then all capabilities will
>>> +be removed from the ambient set.
>>
>> In the case of CLEAR_ALL, is arg3 "don't care", or must it be set to 0?
>
> Must be zero.

Okay, cool. Probably that should be noted here.

-Kees

-- 
Kees Cook
Chrome OS Security
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

[PATCH v2] capabilities.7, prctl.2: Document ambient capabilities Andy Lutomirski <luto@kernel.org> - 2015-09-29 03:10 +0200
  Re: [PATCH v2] capabilities.7, prctl.2: Document ambient capabilities Kees Cook <keescook@chromium.org> - 2015-09-29 19:50 +0200
    Re: [PATCH v2] capabilities.7, prctl.2: Document ambient capabilities Andy Lutomirski <luto@amacapital.net> - 2015-09-29 20:00 +0200
      Re: [PATCH v2] capabilities.7, prctl.2: Document ambient capabilities Kees Cook <keescook@chromium.org> - 2015-09-29 20:00 +0200

csiph-web