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| author | Alexey Budankov <alexey.budankov@linux.intel.com> | 2020-08-05 10:56:56 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-08-06 15:03:20 +0200 |
| commit | 45fd22da97c6125d8d0d35bd1791e7c0c4175279 (patch) | |
| tree | 5329710d5f59f32fbe1fdc2edfaa083c71a7a13f | |
| parent | 2324d50d051ec0f14a548e78554fb02513d6dcef (diff) | |
| download | linux-45fd22da97c6125d8d0d35bd1791e7c0c4175279.tar.bz2 | |
perf/core: Take over CAP_SYS_PTRACE creds to CAP_PERFMON capability
Open access to per-process monitoring for CAP_PERFMON only
privileged processes [1]. Extend ptrace_may_access() check
in perf_events subsystem with perfmon_capable() to simplify
user experience and make monitoring more secure by reducing
attack surface.
[1] https://lore.kernel.org/lkml/7776fa40-6c65-2aa6-1322-eb3a01201000@linux.intel.com/
Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/6e8392ff-4732-0012-2949-e1587709f0f6@linux.intel.com
| -rw-r--r-- | kernel/events/core.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 78e69e10482a..41e0cefb429b 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -11689,7 +11689,7 @@ SYSCALL_DEFINE5(perf_event_open, goto err_task; /* - * Reuse ptrace permission checks for now. + * Preserve ptrace permission check for backwards compatibility. * * We must hold exec_update_mutex across this and any potential * perf_install_in_context() call for this new event to @@ -11697,7 +11697,7 @@ SYSCALL_DEFINE5(perf_event_open, * perf_event_exit_task() that could imply). */ err = -EACCES; - if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) + if (!perfmon_capable() && !ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) goto err_cred; } |