Messages in this thread Patch in this message | | | Date | Fri, 15 Mar 2019 04:29:07 -0700 | From | tip-bot for Peter Zijlstra <> | Subject | [tip:perf/urgent] perf/x86/intel: Fix memory corruption |
| |
Commit-ID: ede271b059463731cbd6dffe55ffd70d7dbe8392 Gitweb: https://git.kernel.org/tip/ede271b059463731cbd6dffe55ffd70d7dbe8392 Author: Peter Zijlstra <peterz@infradead.org> AuthorDate: Thu, 14 Mar 2019 14:01:14 +0100 Committer: Thomas Gleixner <tglx@linutronix.de> CommitDate: Fri, 15 Mar 2019 12:22:51 +0100
perf/x86/intel: Fix memory corruption
Through:
validate_event() x86_pmu.get_event_constraints(.idx=-1) tfa_get_event_constraints() dyn_constraint()
cpuc->constraint_list[-1] is used, which is an obvious out-of-bound access.
In this case, simply skip the TFA constraint code, there is no event constraint with just PMC3, therefore the code will never result in the empty set.
Fixes: 400816f60c54 ("perf/x86/intel: Implement support for TSX Force Abort") Reported-by: Tony Jones <tonyj@suse.com> Reported-by: "DSouza, Nelson" <nelson.dsouza@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Tony Jones <tonyj@suse.com> Tested-by: "DSouza, Nelson" <nelson.dsouza@intel.com> Cc: eranian@google.com Cc: jolsa@redhat.com Cc: stable@kernel.org Link: https://lkml.kernel.org/r/20190314130705.441549378@infradead.org
--- arch/x86/events/intel/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 35102ecdfc8d..92dfeb343a6a 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3410,7 +3410,7 @@ tfa_get_event_constraints(struct cpu_hw_events *cpuc, int idx, /* * Without TFA we must not use PMC3. */ - if (!allow_tsx_force_abort && test_bit(3, c->idxmsk)) { + if (!allow_tsx_force_abort && test_bit(3, c->idxmsk) && idx >= 0) { c = dyn_constraint(cpuc, c, idx); c->idxmsk64 &= ~(1ULL << 3); c->weight--;
| |