Description: Possible privilege escalation due to lack of locking around changing event->ctx
References:
Notes:
 bwh> This is left over from an incomplete fix for CVE-2016-6786.
 bwh> Note dependency on commit 130056275ade "perf: Do not double free".
Bugs:
upstream: released (4.10-rc4) [321027c1fe77f892f4ea07846aeae08cefbbb290]
4.9-upstream-stable: released (4.9.7) [922813f4d66fb317e8602d058d03a1619af1ffd0]
3.16-upstream-stable: released (3.16.40) [perf-core-fix-concurrent-sys_perf_event_open-vs.-move_group-race.patch]
3.2-upstream-stable: released (3.2.85) [perf-core-fix-concurrent-sys_perf_event_open-vs.-move_group-race.patch]
sid: released (4.9.10-1)
3.16-jessie-security: released (3.16.39-1+deb8u1) [bugfix/all/perf-core-Fix-concurrent-sys_perf_event_open-vs.-mov.patch]
3.2-wheezy-security: released (3.2.84-2) [bugfix/all/perf-core-fix-concurrent-sys_perf_event_open-vs.-mov.patch]