diff mbox series

[linux-next,1/2] perf: Remove unnecessary parameter of security check

Message ID 20241223070650.2810747-2-luogengkun@huaweicloud.com (mailing list archive)
State Accepted
Delegated to: Paul Moore
Headers show
Series Fix perf security check problem | expand

Commit Message

Luo Gengkun Dec. 23, 2024, 7:06 a.m. UTC 
It seems that the attr parameter was never been used in security
checks since it was first introduced by:

commit da97e18458fb ("perf_event: Add support for LSM and SELinux checks")

so remove it.

Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
---
 arch/x86/events/intel/bts.c     |  2 +-
 arch/x86/events/intel/core.c    |  2 +-
 arch/x86/events/intel/p4.c      |  2 +-
 drivers/perf/arm_spe_pmu.c      |  4 ++--
 include/linux/lsm_hook_defs.h   |  2 +-
 include/linux/perf_event.h      | 10 +++++-----
 include/linux/security.h        |  5 ++---
 kernel/events/core.c            | 14 +++++++-------
 kernel/trace/trace_event_perf.c |  4 ++--
 security/security.c             |  5 ++---
 security/selinux/hooks.c        |  2 +-
 11 files changed, 25 insertions(+), 27 deletions(-)

Comments

Paul Moore Jan. 5, 2025, 2:45 a.m. UTC | #1 
On Mon, Dec 23, 2024 at 1:57 AM Luo Gengkun <luogengkun@huaweicloud.com> wrote:
>
> It seems that the attr parameter was never been used in security
> checks since it was first introduced by:
>
> commit da97e18458fb ("perf_event: Add support for LSM and SELinux checks")
>
> so remove it.
>
> Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
> ---
>  arch/x86/events/intel/bts.c     |  2 +-
>  arch/x86/events/intel/core.c    |  2 +-
>  arch/x86/events/intel/p4.c      |  2 +-
>  drivers/perf/arm_spe_pmu.c      |  4 ++--
>  include/linux/lsm_hook_defs.h   |  2 +-
>  include/linux/perf_event.h      | 10 +++++-----
>  include/linux/security.h        |  5 ++---
>  kernel/events/core.c            | 14 +++++++-------
>  kernel/trace/trace_event_perf.c |  4 ++--
>  security/security.c             |  5 ++---
>  security/selinux/hooks.c        |  2 +-
>  11 files changed, 25 insertions(+), 27 deletions(-)

This patch seems fine to me from a LSM and SELinux perspective, but
I'd want to see an ACK from the perf folks before I merge this.

I'll also leave patch 2/2 for the perf folks as it seems largely
unrelated to this patch.
Luo Gengkun Jan. 7, 2025, 1:52 a.m. UTC | #2 
On 2025/1/5 10:45, Paul Moore wrote:
> On Mon, Dec 23, 2024 at 1:57 AM Luo Gengkun <luogengkun@huaweicloud.com> wrote:
>> It seems that the attr parameter was never been used in security
>> checks since it was first introduced by:
>>
>> commit da97e18458fb ("perf_event: Add support for LSM and SELinux checks")
>>
>> so remove it.
>>
>> Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
>> ---
>>   arch/x86/events/intel/bts.c     |  2 +-
>>   arch/x86/events/intel/core.c    |  2 +-
>>   arch/x86/events/intel/p4.c      |  2 +-
>>   drivers/perf/arm_spe_pmu.c      |  4 ++--
>>   include/linux/lsm_hook_defs.h   |  2 +-
>>   include/linux/perf_event.h      | 10 +++++-----
>>   include/linux/security.h        |  5 ++---
>>   kernel/events/core.c            | 14 +++++++-------
>>   kernel/trace/trace_event_perf.c |  4 ++--
>>   security/security.c             |  5 ++---
>>   security/selinux/hooks.c        |  2 +-
>>   11 files changed, 25 insertions(+), 27 deletions(-)
> This patch seems fine to me from a LSM and SELinux perspective, but
> I'd want to see an ACK from the perf folks before I merge this.
>
> I'll also leave patch 2/2 for the perf folks as it seems largely
> unrelated to this patch.

Thanks for your review

Gengkun
Ingo Molnar Feb. 25, 2025, 9:59 p.m. UTC | #3 
* Paul Moore <paul@paul-moore.com> wrote:

> On Mon, Dec 23, 2024 at 1:57 AM Luo Gengkun <luogengkun@huaweicloud.com> wrote:
> >
> > It seems that the attr parameter was never been used in security
> > checks since it was first introduced by:
> >
> > commit da97e18458fb ("perf_event: Add support for LSM and SELinux checks")
> >
> > so remove it.
> >
> > Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
> > ---
> >  arch/x86/events/intel/bts.c     |  2 +-
> >  arch/x86/events/intel/core.c    |  2 +-
> >  arch/x86/events/intel/p4.c      |  2 +-
> >  drivers/perf/arm_spe_pmu.c      |  4 ++--
> >  include/linux/lsm_hook_defs.h   |  2 +-
> >  include/linux/perf_event.h      | 10 +++++-----
> >  include/linux/security.h        |  5 ++---
> >  kernel/events/core.c            | 14 +++++++-------
> >  kernel/trace/trace_event_perf.c |  4 ++--
> >  security/security.c             |  5 ++---
> >  security/selinux/hooks.c        |  2 +-
> >  11 files changed, 25 insertions(+), 27 deletions(-)
> 
> This patch seems fine to me from a LSM and SELinux perspective, but
> I'd want to see an ACK from the perf folks before I merge this.

A belated:

  Reviewed-by: Ingo Molnar <mingo@kernel.org>

Patch still seems to apply fine.

Thanks,

	Ingo
Paul Moore Feb. 26, 2025, 7:13 p.m. UTC | #4 
On Dec 23, 2024 Luo Gengkun <luogengkun@huaweicloud.com> wrote:
> 
> It seems that the attr parameter was never been used in security
> checks since it was first introduced by:
> 
> commit da97e18458fb ("perf_event: Add support for LSM and SELinux checks")
> 
> so remove it.
> 
> Signed-off-by: Luo Gengkun <luogengkun@huaweicloud.com>
> Reviewed-by: Ingo Molnar <mingo@kernel.org>
> ---
>  arch/x86/events/intel/bts.c     |  2 +-
>  arch/x86/events/intel/core.c    |  2 +-
>  arch/x86/events/intel/p4.c      |  2 +-
>  drivers/perf/arm_spe_pmu.c      |  4 ++--
>  include/linux/lsm_hook_defs.h   |  2 +-
>  include/linux/perf_event.h      | 10 +++++-----
>  include/linux/security.h        |  5 ++---
>  kernel/events/core.c            | 14 +++++++-------
>  kernel/trace/trace_event_perf.c |  4 ++--
>  security/security.c             |  5 ++---
>  security/selinux/hooks.c        |  2 +-
>  11 files changed, 25 insertions(+), 27 deletions(-)

Now that we have Ingo's Reviewed-by, I've gone ahead and merged
patch 1/2 into lsm/dev, thanks everyone!

--
paul-moore.com
diff mbox series

Patch

diff --git a/arch/x86/events/intel/bts.c b/arch/x86/events/intel/bts.c
index 8f78b0c900ef..485a09d61adf 100644
--- a/arch/x86/events/intel/bts.c
+++ b/arch/x86/events/intel/bts.c
@@ -559,7 +559,7 @@  static int bts_event_init(struct perf_event *event)
 	 * to the user in a zero-copy fashion.
 	 */
 	if (event->attr.exclude_kernel) {
-		ret = perf_allow_kernel(&event->attr);
+		ret = perf_allow_kernel();
 		if (ret)
 			return ret;
 	}
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index 103ee41907c7..3b65df32daee 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -4150,7 +4150,7 @@  static int intel_pmu_hw_config(struct perf_event *event)
 	if (x86_pmu.version < 3)
 		return -EINVAL;
 
-	ret = perf_allow_cpu(&event->attr);
+	ret = perf_allow_cpu();
 	if (ret)
 		return ret;
 
diff --git a/arch/x86/events/intel/p4.c b/arch/x86/events/intel/p4.c
index 844bc4fc4724..78d78b8a1530 100644
--- a/arch/x86/events/intel/p4.c
+++ b/arch/x86/events/intel/p4.c
@@ -776,7 +776,7 @@  static int p4_validate_raw_event(struct perf_event *event)
 	 * the user needs special permissions to be able to use it
 	 */
 	if (p4_ht_active() && p4_event_bind_map[v].shared) {
-		v = perf_allow_cpu(&event->attr);
+		v = perf_allow_cpu();
 		if (v)
 			return v;
 	}
diff --git a/drivers/perf/arm_spe_pmu.c b/drivers/perf/arm_spe_pmu.c
index fd5b78732603..a55d10956ff6 100644
--- a/drivers/perf/arm_spe_pmu.c
+++ b/drivers/perf/arm_spe_pmu.c
@@ -50,7 +50,7 @@  static_assert((PERF_EVENT_FLAG_ARCH & SPE_PMU_HW_FLAGS_CX) == SPE_PMU_HW_FLAGS_C
 
 static void set_spe_event_has_cx(struct perf_event *event)
 {
-	if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && !perf_allow_kernel(&event->attr))
+	if (IS_ENABLED(CONFIG_PID_IN_CONTEXTIDR) && !perf_allow_kernel())
 		event->hw.flags |= SPE_PMU_HW_FLAGS_CX;
 }
 
@@ -746,7 +746,7 @@  static int arm_spe_pmu_event_init(struct perf_event *event)
 	set_spe_event_has_cx(event);
 	reg = arm_spe_event_to_pmscr(event);
 	if (reg & (PMSCR_EL1_PA | PMSCR_EL1_PCT))
-		return perf_allow_kernel(&event->attr);
+		return perf_allow_kernel();
 
 	return 0;
 }
diff --git a/include/linux/lsm_hook_defs.h b/include/linux/lsm_hook_defs.h
index e2f1ce37c41e..e349e585cc07 100644
--- a/include/linux/lsm_hook_defs.h
+++ b/include/linux/lsm_hook_defs.h
@@ -445,7 +445,7 @@  LSM_HOOK(int, 0, bpf_token_capable, const struct bpf_token *token, int cap)
 LSM_HOOK(int, 0, locked_down, enum lockdown_reason what)
 
 #ifdef CONFIG_PERF_EVENTS
-LSM_HOOK(int, 0, perf_event_open, struct perf_event_attr *attr, int type)
+LSM_HOOK(int, 0, perf_event_open, int type)
 LSM_HOOK(int, 0, perf_event_alloc, struct perf_event *event)
 LSM_HOOK(int, 0, perf_event_read, struct perf_event *event)
 LSM_HOOK(int, 0, perf_event_write, struct perf_event *event)
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 8333f132f4a9..5d2ec4283ebf 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1672,22 +1672,22 @@  static inline int perf_is_paranoid(void)
 	return sysctl_perf_event_paranoid > -1;
 }
 
-int perf_allow_kernel(struct perf_event_attr *attr);
+int perf_allow_kernel(void);
 
-static inline int perf_allow_cpu(struct perf_event_attr *attr)
+static inline int perf_allow_cpu(void)
 {
 	if (sysctl_perf_event_paranoid > 0 && !perfmon_capable())
 		return -EACCES;
 
-	return security_perf_event_open(attr, PERF_SECURITY_CPU);
+	return security_perf_event_open(PERF_SECURITY_CPU);
 }
 
-static inline int perf_allow_tracepoint(struct perf_event_attr *attr)
+static inline int perf_allow_tracepoint(void)
 {
 	if (sysctl_perf_event_paranoid > -1 && !perfmon_capable())
 		return -EPERM;
 
-	return security_perf_event_open(attr, PERF_SECURITY_TRACEPOINT);
+	return security_perf_event_open(PERF_SECURITY_TRACEPOINT);
 }
 
 extern int perf_exclude_event(struct perf_event *event, struct pt_regs *regs);
diff --git a/include/linux/security.h b/include/linux/security.h
index 980b6c207cad..a3b35a699256 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -2324,14 +2324,13 @@  struct perf_event_attr;
 struct perf_event;
 
 #ifdef CONFIG_SECURITY
-extern int security_perf_event_open(struct perf_event_attr *attr, int type);
+extern int security_perf_event_open(int type);
 extern int security_perf_event_alloc(struct perf_event *event);
 extern void security_perf_event_free(struct perf_event *event);
 extern int security_perf_event_read(struct perf_event *event);
 extern int security_perf_event_write(struct perf_event *event);
 #else
-static inline int security_perf_event_open(struct perf_event_attr *attr,
-					   int type)
+static inline int security_perf_event_open(int type)
 {
 	return 0;
 }
diff --git a/kernel/events/core.c b/kernel/events/core.c
index b2bc67791f84..f2cb450eb134 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4883,7 +4883,7 @@  find_get_context(struct task_struct *task, struct perf_event *event)
 
 	if (!task) {
 		/* Must be root to operate on a CPU event: */
-		err = perf_allow_cpu(&event->attr);
+		err = perf_allow_cpu();
 		if (err)
 			return ERR_PTR(err);
 
@@ -12488,7 +12488,7 @@  static int perf_copy_attr(struct perf_event_attr __user *uattr,
 		}
 		/* privileged levels capture (kernel, hv): check permissions */
 		if (mask & PERF_SAMPLE_BRANCH_PERM_PLM) {
-			ret = perf_allow_kernel(attr);
+			ret = perf_allow_kernel();
 			if (ret)
 				return ret;
 		}
@@ -12745,12 +12745,12 @@  SYSCALL_DEFINE5(perf_event_open,
 		return err;
 
 	/* Do we allow access to perf_event_open(2) ? */
-	err = security_perf_event_open(&attr, PERF_SECURITY_OPEN);
+	err = security_perf_event_open(PERF_SECURITY_OPEN);
 	if (err)
 		return err;
 
 	if (!attr.exclude_kernel) {
-		err = perf_allow_kernel(&attr);
+		err = perf_allow_kernel();
 		if (err)
 			return err;
 	}
@@ -12770,7 +12770,7 @@  SYSCALL_DEFINE5(perf_event_open,
 
 	/* Only privileged users can get physical addresses */
 	if ((attr.sample_type & PERF_SAMPLE_PHYS_ADDR)) {
-		err = perf_allow_kernel(&attr);
+		err = perf_allow_kernel();
 		if (err)
 			return err;
 	}
@@ -13603,12 +13603,12 @@  const struct perf_event_attr *perf_event_attrs(struct perf_event *event)
 	return &event->attr;
 }
 
-int perf_allow_kernel(struct perf_event_attr *attr)
+int perf_allow_kernel(void)
 {
 	if (sysctl_perf_event_paranoid > 1 && !perfmon_capable())
 		return -EACCES;
 
-	return security_perf_event_open(attr, PERF_SECURITY_KERNEL);
+	return security_perf_event_open(PERF_SECURITY_KERNEL);
 }
 EXPORT_SYMBOL_GPL(perf_allow_kernel);
 
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 3ff9caa4a71b..a6bb7577e8c5 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -49,7 +49,7 @@  static int perf_trace_event_perm(struct trace_event_call *tp_event,
 
 	/* The ftrace function trace is allowed only for root. */
 	if (ftrace_event_is_function(tp_event)) {
-		ret = perf_allow_tracepoint(&p_event->attr);
+		ret = perf_allow_tracepoint();
 		if (ret)
 			return ret;
 
@@ -86,7 +86,7 @@  static int perf_trace_event_perm(struct trace_event_call *tp_event,
 	 * ...otherwise raw tracepoint data can be a severe data leak,
 	 * only allow root to have these.
 	 */
-	ret = perf_allow_tracepoint(&p_event->attr);
+	ret = perf_allow_tracepoint();
 	if (ret)
 		return ret;
 
diff --git a/security/security.c b/security/security.c
index 1db835c05a78..ad9655aa1322 100644
--- a/security/security.c
+++ b/security/security.c
@@ -5885,16 +5885,15 @@  EXPORT_SYMBOL(security_bdev_setintegrity);
 #ifdef CONFIG_PERF_EVENTS
 /**
  * security_perf_event_open() - Check if a perf event open is allowed
- * @attr: perf event attribute
  * @type: type of event
  *
  * Check whether the @type of perf_event_open syscall is allowed.
  *
  * Return: Returns 0 if permission is granted.
  */
-int security_perf_event_open(struct perf_event_attr *attr, int type)
+int security_perf_event_open(int type)
 {
-	return call_int_hook(perf_event_open, attr, type);
+	return call_int_hook(perf_event_open, type);
 }
 
 /**
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index a503b8fd6611..14c7d331c3b6 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -7040,7 +7040,7 @@  struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
 };
 
 #ifdef CONFIG_PERF_EVENTS
-static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
+static int selinux_perf_event_open(int type)
 {
 	u32 requested, sid = current_sid();