linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] x86/hw_breakpoints, kprobes: Remove kprobes ifdeffery
@ 2019-01-27 13:12 Borislav Petkov
  2019-01-28 13:57 ` Masami Hiramatsu
  2019-01-30 11:03 ` [tip:x86/cleanups] " tip-bot for Borislav Petkov
  0 siblings, 2 replies; 3+ messages in thread
From: Borislav Petkov @ 2019-01-27 13:12 UTC (permalink / raw)
  To: X86 ML
  Cc: LKML, Anil S Keshavamurthy, David S. Miller, Frederic Weisbecker,
	H. Peter Anvin, Ingo Molnar, Masami Hiramatsu, Naveen N. Rao,
	Thomas Gleixner

From: Borislav Petkov <bp@suse.de>

Remove the ifdeffery in the breakpoint parsing arch_build_bp_info() by
adding a within_kprobe_blacklist() stub for the !CONFIG_KPROBES case.

It is returning true when kprobes are not enabled to mean that any
address is within the kprobes blacklist on such kernels and thus not
allow kernel breakpoints on non-kprobes kernels.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/kernel/hw_breakpoint.c | 4 ----
 include/linux/kprobes.h         | 5 +++++
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index 7d6f91f2869a..ff9bfd40429e 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -261,12 +261,8 @@ static int arch_build_bp_info(struct perf_event *bp,
 		 * allow kernel breakpoints at all.
 		 */
 		if (attr->bp_addr >= TASK_SIZE_MAX) {
-#ifdef CONFIG_KPROBES
 			if (within_kprobe_blacklist(attr->bp_addr))
 				return -EINVAL;
-#else
-			return -EINVAL;
-#endif
 		}
 
 		hw->type = X86_BREAKPOINT_EXECUTE;
diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h
index e07e91daaacc..201f0f2683f2 100644
--- a/include/linux/kprobes.h
+++ b/include/linux/kprobes.h
@@ -442,6 +442,11 @@ static inline int enable_kprobe(struct kprobe *kp)
 {
 	return -ENOSYS;
 }
+
+static inline bool within_kprobe_blacklist(unsigned long addr)
+{
+	return true;
+}
 #endif /* CONFIG_KPROBES */
 static inline int disable_kretprobe(struct kretprobe *rp)
 {
-- 
2.19.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2019-01-30 11:04 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-01-27 13:12 [PATCH] x86/hw_breakpoints, kprobes: Remove kprobes ifdeffery Borislav Petkov
2019-01-28 13:57 ` Masami Hiramatsu
2019-01-30 11:03 ` [tip:x86/cleanups] " tip-bot for Borislav Petkov

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).