1 files changed, 12 insertions, 2 deletions

diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
index da02e9cc3754..de341d4ec92a 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c
@@ -442,8 +442,18 @@ static int branch_type(unsigned long from, unsigned long to)
                         return X86_BR_NONE;
 
                 addr = buf;
-        } else
-                addr = (void *)from;
+        } else {
+                /*
+                 * The LBR logs any address in the IP, even if the IP just
+                 * faulted. This means userspace can control the from address.
+                 * Ensure we don't blindy read any address by validating it is
+                 * a known text address.
+                 */
+                if (kernel_text_address(from))
+                        addr = (void *)from;
+                else
+                        return X86_BR_NONE;
+        }
 
         /*
          * decoder needs to know the ABI especially