2019-10-03 07:57:00

by Greg KH

[permalink] [raw]
Subject: Re: Patch "perf ftrace: Use CAP_SYS_ADMIN instead of euid==0" has been added to the 5.3-stable tree

On Tue, Oct 01, 2019 at 01:15:54PM -0400, Sasha Levin wrote:
> This is a note to let you know that I've just added the patch titled
>
> perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
>
> to the 5.3-stable tree which can be found at:
> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
>
> The filename of the patch is:
> perf-ftrace-use-cap_sys_admin-instead-of-euid-0.patch
> and it can be found in the queue-5.3 subdirectory.
>
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <[email protected]> know about it.
>
>
>
> commit 54a277c389061fc501624f51a13426d7b797f5f7
> Author: Igor Lubashev <[email protected]>
> Date: Wed Aug 7 10:44:17 2019 -0400
>
> perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
>
> [ Upstream commit c766f3df635de14295e410c6dd5410bc416c24a0 ]


Sasha, this patch is breaking the build of perf in the stable branches.
Can you fix it up, or drop it?

thanks,

greg k-h


2019-10-03 15:13:52

by Lubashev, Igor

[permalink] [raw]
Subject: RE: Patch "perf ftrace: Use CAP_SYS_ADMIN instead of euid==0" has been added to the 5.3-stable tree

> On Thu, Oct 3, 2019 at 3:50 AM Greg KH <[email protected]> wrote:
> Sent: Thursday, October 3, 2019 3:50 AM
>
> On Tue, Oct 01, 2019 at 01:15:54PM -0400, Sasha Levin wrote:
> > This is a note to let you know that I've just added the patch titled
> >
> > perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
> >
> > to the 5.3-stable tree which can be found at:
> >
> > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;
> > a=summary
> >
> > The filename of the patch is:
> > perf-ftrace-use-cap_sys_admin-instead-of-euid-0.patch
> > and it can be found in the queue-5.3 subdirectory.
> >
> > If you, or anyone else, feels it should not be added to the stable
> > tree, please let <[email protected]> know about it.
> >
> >
> >
> > commit 54a277c389061fc501624f51a13426d7b797f5f7
> > Author: Igor Lubashev <[email protected]>
> > Date: Wed Aug 7 10:44:17 2019 -0400
> >
> > perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
> >
> > [ Upstream commit c766f3df635de14295e410c6dd5410bc416c24a0 ]
>
>
> Sasha, this patch is breaking the build of perf in the stable branches.
> Can you fix it up, or drop it?

This patch is fixing what's been broken forever in perf, so it is improving perf tool. But it is not fixing a vuln in the kernel itself.

In any case, this patch is a part of a series. You would need the following to make that patch compile:
97993bd6eb89 perf tools: Add NO_LIBCAP=1 to the minimal build test
c22e150e3afa perf tools: Add helpers to use capabilities if present

Also, if you believe this update to perf tool warrants inclusion in a stable update, I'd rather point you at the entire series:

d06e5fad8c46 perf tools: Warn that perf_event_paranoid can restrict kernel symbols
8859aedefefe perf symbols: Use CAP_SYSLOG with kptr_restrict checks
aa97293ff129 perf evsel: Kernel profiling is disallowed only when perf_event_paranoid > 1
dda1bf8ea78a perf tools: Use CAP_SYS_ADMIN with perf_event_paranoid checks
e9a6882f267a perf event: Check ref_reloc_sym before using it
73e5de70dca0 perf ftrace: Improve error message about capability to use ftrace
c766f3df635d perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
083c1359b0e0 perf tools: Add CAP_SYSLOG define for older systems
97993bd6eb89 perf tools: Add NO_LIBCAP=1 to the minimal build test
c22e150e3afa perf tools: Add helpers to use capabilities if present
74d5f3d06f70 tools build: Add capability-related feature detection

Best,

- Igor

2019-10-03 16:00:22

by Greg KH

[permalink] [raw]
Subject: Re: Patch "perf ftrace: Use CAP_SYS_ADMIN instead of euid==0" has been added to the 5.3-stable tree

On Thu, Oct 03, 2019 at 03:10:02PM +0000, Lubashev, Igor wrote:
> > On Thu, Oct 3, 2019 at 3:50 AM Greg KH <[email protected]> wrote:
> > Sent: Thursday, October 3, 2019 3:50 AM
> >
> > On Tue, Oct 01, 2019 at 01:15:54PM -0400, Sasha Levin wrote:
> > > This is a note to let you know that I've just added the patch titled
> > >
> > > perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
> > >
> > > to the 5.3-stable tree which can be found at:
> > >
> > > http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;
> > > a=summary
> > >
> > > The filename of the patch is:
> > > perf-ftrace-use-cap_sys_admin-instead-of-euid-0.patch
> > > and it can be found in the queue-5.3 subdirectory.
> > >
> > > If you, or anyone else, feels it should not be added to the stable
> > > tree, please let <[email protected]> know about it.
> > >
> > >
> > >
> > > commit 54a277c389061fc501624f51a13426d7b797f5f7
> > > Author: Igor Lubashev <[email protected]>
> > > Date: Wed Aug 7 10:44:17 2019 -0400
> > >
> > > perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
> > >
> > > [ Upstream commit c766f3df635de14295e410c6dd5410bc416c24a0 ]
> >
> >
> > Sasha, this patch is breaking the build of perf in the stable branches.
> > Can you fix it up, or drop it?
>
> This patch is fixing what's been broken forever in perf, so it is improving perf tool. But it is not fixing a vuln in the kernel itself.
>
> In any case, this patch is a part of a series. You would need the following to make that patch compile:
> 97993bd6eb89 perf tools: Add NO_LIBCAP=1 to the minimal build test
> c22e150e3afa perf tools: Add helpers to use capabilities if present
>
> Also, if you believe this update to perf tool warrants inclusion in a stable update, I'd rather point you at the entire series:
>
> d06e5fad8c46 perf tools: Warn that perf_event_paranoid can restrict kernel symbols
> 8859aedefefe perf symbols: Use CAP_SYSLOG with kptr_restrict checks
> aa97293ff129 perf evsel: Kernel profiling is disallowed only when perf_event_paranoid > 1
> dda1bf8ea78a perf tools: Use CAP_SYS_ADMIN with perf_event_paranoid checks
> e9a6882f267a perf event: Check ref_reloc_sym before using it
> 73e5de70dca0 perf ftrace: Improve error message about capability to use ftrace
> c766f3df635d perf ftrace: Use CAP_SYS_ADMIN instead of euid==0
> 083c1359b0e0 perf tools: Add CAP_SYSLOG define for older systems
> 97993bd6eb89 perf tools: Add NO_LIBCAP=1 to the minimal build test
> c22e150e3afa perf tools: Add helpers to use capabilities if present
> 74d5f3d06f70 tools build: Add capability-related feature detection

Thanks for the info. I've dropped the original patch here from the
stable queues, as it doesn't look like it really matters at the moment.

thanks,

greg k-h