1 files changed, 24 insertions, 2 deletions

diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 9ed9ae3a48b3..89e8a050c43a 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -308,6 +308,28 @@ int dbg_release_bp_slot(struct perf_event *bp)
         return 0;
 }
 
+static int validate_hw_breakpoint(struct perf_event *bp)
+{
+        int ret;
+
+        ret = arch_validate_hwbkpt_settings(bp);
+        if (ret)
+                return ret;
+
+        if (arch_check_bp_in_kernelspace(bp)) {
+                if (bp->attr.exclude_kernel)
+                        return -EINVAL;
+                /*
+                 * Don't let unprivileged users set a breakpoint in the trap
+                 * path to avoid trap recursion attacks.
+                 */
+                if (!capable(CAP_SYS_ADMIN))
+                        return -EPERM;
+        }
+
+        return 0;
+}
+
 int register_perf_hw_breakpoint(struct perf_event *bp)
 {
         int ret;
@@ -316,7 +338,7 @@ int register_perf_hw_breakpoint(struct perf_event *bp)
         if (ret)
                 return ret;
 
-        ret = arch_validate_hwbkpt_settings(bp, bp->ctx->task);
+        ret = validate_hw_breakpoint(bp);
 
         /* if arch_validate_hwbkpt_settings() fails then release bp slot */
         if (ret)
@@ -363,7 +385,7 @@ int modify_user_hw_breakpoint(struct perf_event *bp, struct perf_event_attr *att
         if (attr->disabled)
                 goto end;
 
-        err = arch_validate_hwbkpt_settings(bp, bp->ctx->task);
+        err = validate_hw_breakpoint(bp);
         if (!err)
                 perf_event_enable(bp);