diff options
| author | Jeff Vander Stoep <jeffv@google.com> | 2016-05-29 14:22:32 -0700 |
|---|---|---|
| committer | Gerrit - the friendly Code Review server <code-review@localhost> | 2016-09-13 12:23:33 -0700 |
| commit | 1a565f59cb3b227e0c7c1c5b58951aed5a27b5d6 (patch) | |
| tree | dc300c937957a981de72e361073f301ddfb37c9e /kernel/events | |
| parent | a647f40d2b02cbc0456037de049d4d9e53083420 (diff) | |
FROMLIST: security,perf: Allow further restriction of perf_event_open
When kernel.perf_event_open is set to 3 (or greater), disallow all
access to performance events by users without CAP_SYS_ADMIN.
Add a Kconfig symbol CONFIG_SECURITY_PERF_EVENTS_RESTRICT that
makes this value the default.
This is based on a similar feature in grsecurity
(CONFIG_GRKERNSEC_PERF_HARDEN). This version doesn't include making
the variable read-only. It also allows enabling further restriction
at run-time regardless of whether the default is changed.
https://lkml.org/lkml/2016/1/11/587
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Git-repo: https://android.googlesource.com/kernel/common.git
Git-commit: 012b0adcf7299f6509d4984cf46ee11e6eaed4e4
[d-cagle@codeaurora.org: Resolve trivial merge conflicts]
Signed-off-by: Dennis Cagle <d-cagle@codeaurora.org>
Bug: 29054680
Change-Id: Iff5bff4fc1042e85866df9faa01bce8d04335ab8
Diffstat (limited to 'kernel/events')
| -rw-r--r-- | kernel/events/core.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/kernel/events/core.c b/kernel/events/core.c index 32e2617d654f..d6ec580584b6 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -176,9 +176,12 @@ static struct srcu_struct pmus_srcu; * 0 - disallow raw tracepoint access for unpriv * 1 - disallow cpu events for unpriv * 2 - disallow kernel profiling for unpriv + * 3 - disallow all unpriv perf event use */ #ifdef CONFIG_PERF_EVENTS_USERMODE int sysctl_perf_event_paranoid __read_mostly = -1; +#elif defined CONFIG_SECURITY_PERF_EVENTS_RESTRICT +int sysctl_perf_event_paranoid __read_mostly = 3; #else int sysctl_perf_event_paranoid __read_mostly = 1; #endif @@ -8325,6 +8328,9 @@ SYSCALL_DEFINE5(perf_event_open, if (flags & ~PERF_FLAG_ALL) return -EINVAL; + if (perf_paranoid_any() && !capable(CAP_SYS_ADMIN)) + return -EACCES; + err = perf_copy_attr(attr_uptr, &attr); if (err) return err; |