Fix !CONFIG_DMAR build failure introduced by Intel IOMMU Pass Through Support

[mirror_ubuntu-artful-kernel.git] / kernel / ptrace.c

diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 64191fa09b7e9eb8c5672caa0b3764dc9a13a354..dfcd83ceee3b246326cbec2a6eadb27abdba7823 100644 (file)
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -604,10 +604,11 @@ repeat:
                ret = security_ptrace_traceme(current->parent);
 
                /*
-                * Set the ptrace bit in the process ptrace flags.
-                * Then link us on our parent's ptraced list.
+                * Check PF_EXITING to ensure ->real_parent has not passed
+                * exit_ptrace(). Otherwise we don't report the error but
+                * pretend ->real_parent untraces us right after return.
                 */
-               if (!ret) {
+               if (!ret && !(current->real_parent->flags & PF_EXITING)) {
                        current->ptrace |= PT_PTRACED;
                        __ptrace_link(current, current->real_parent);
                }