lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Sat, 25 May 2019 10:54:47 +1000 (AEST)
From:   Michael Ellerman <patch-notifications@...erman.id.au>
To:     Ravi Bangoria <ravi.bangoria@...ux.ibm.com>, peterz@...radead.org,
        jolsa@...hat.com, maddy@...ux.vnet.ibm.com
Cc:     Ravi Bangoria <ravi.bangoria@...ux.ibm.com>,
        linuxppc-dev@...ts.ozlabs.org, linux-kernel@...r.kernel.org,
        acme@...nel.org
Subject: Re: [PATCH 2/2] powerpc/perf: Fix mmcra corruption by bhrb_filter

On Sat, 2019-05-11 at 02:42:17 UTC, Ravi Bangoria wrote:
> Consider a scenario where user creates two events:
> 
>   1st event:
>     attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;
>     attr.branch_sample_type = PERF_SAMPLE_BRANCH_ANY;
>     fd = perf_event_open(attr, 0, 1, -1, 0);
> 
>   This sets cpuhw->bhrb_filter to 0 and returns valid fd.
> 
>   2nd event:
>     attr.sample_type |= PERF_SAMPLE_BRANCH_STACK;
>     attr.branch_sample_type = PERF_SAMPLE_BRANCH_CALL;
>     fd = perf_event_open(attr, 0, 1, -1, 0);
> 
>   It overrides cpuhw->bhrb_filter to -1 and returns with error.
> 
> Now if power_pmu_enable() gets called by any path other than
> power_pmu_add(), ppmu->config_bhrb(-1) will set mmcra to -1.
> 
> Signed-off-by: Ravi Bangoria <ravi.bangoria@...ux.ibm.com>
> Reviewed-by: Madhavan Srinivasan <maddy@...ux.vnet.ibm.com>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/3202e35ec1c8fc19cea24253ff83edf7

cheers

Powered by blists - more mailing lists