xnu-4570.51.1.tar.gz

[apple/xnu.git] / bsd / dev / dtrace / fbt.c

diff --git a/bsd/dev/dtrace/fbt.c b/bsd/dev/dtrace/fbt.c
index 25f052f1a4b3dd0993ce86b871cc958c4598e7c0..d90a7b15d5a391952d5959dc11fcde2a54275c2e 100644 (file)
--- a/bsd/dev/dtrace/fbt.c
+++ b/bsd/dev/dtrace/fbt.c
@@ -50,6 +50,7 @@
 #include <sys/fbt.h>
 
 #include <sys/dtrace_glue.h>
+#include <san/kasan.h>
 
 /* #include <machine/trap.h> */
 struct savearea_t; /* Used anonymously */
@@ -467,6 +468,14 @@ fbt_excluded(const char* name)
                return TRUE;
        }
 
+#if KASAN
+       if (LIT_STRNSTART(name, "kasan") ||
+               LIT_STRNSTART(name, "__kasan") ||
+               LIT_STRNSTART(name, "__asan")) {
+               return TRUE;
+       }
+#endif
+
        /*
         * Place no probes that could be hit on the way to a panic.
         */
@@ -560,6 +569,13 @@ fbt_enable(void *arg, dtrace_id_t id, void *parg)
        }
 
        if (fbt->fbtp_currentval != fbt->fbtp_patchval) {
+#if KASAN
+               /* Since dtrace probes can call into KASan and vice versa, things can get
+                * very slow if we have a lot of probes. This call will disable the KASan
+                * fakestack after a threshold of probes is reached. */
+               kasan_fakestack_suspend();
+#endif
+
                (void)ml_nofault_copy( (vm_offset_t)&fbt->fbtp_patchval, (vm_offset_t)fbt->fbtp_patchpoint, 
                                                                sizeof(fbt->fbtp_patchval));
                /*
@@ -607,6 +623,10 @@ fbt_disable(void *arg, dtrace_id_t id, void *parg)
                fbt->fbtp_currentval = fbt->fbtp_savedval;
                ASSERT(ctl->mod_nenabled > 0);
                ctl->mod_nenabled--;
+
+#if KASAN
+               kasan_fakestack_resume();
+#endif
            }
        }
        dtrace_membar_consumer();