svn commit: r354854 - head/sys/sys

[David Bright]

Author: dab
Date: Tue Nov 19 14:46:28 2019
New Revision: 354854
URL: https://svnweb.freebsd.org/changeset/base/354854

Log:
  Don't sanitize linker_set
  
  The assumptions of linker_set don't play nicely with
  AddressSanitizer. AddressSanitizer adds a 'redzone' of zeros around
  globals (including those in named sections), whereas linker_set
  assumes they are all packed consecutively like a pointer array. So:
  let's annotate linker_set so that AddressSanitizer ignores it.
  
  Submitted by:	Matthew Bryan <matthew.bryan at isilon.com>
  Reviewed by:	kib, rang_acm.org
  Sponsored by:	Dell EMC Isilon
  Differential Revision:	https://reviews.freebsd.org/D22239

Modified:
  head/sys/sys/cdefs.h
  head/sys/sys/linker_set.h

Modified: head/sys/sys/cdefs.h
==============================================================================
--- head/sys/sys/cdefs.h	Tue Nov 19 13:28:59 2019	(r354853)
+++ head/sys/sys/cdefs.h	Tue Nov 19 14:46:28 2019	(r354854)
@@ -872,6 +872,13 @@
 /* Function should not be analyzed. */
 #define	__no_lock_analysis	__lock_annotate(no_thread_safety_analysis)
 
+/* Function or variable should not be sanitized, ie. by AddressSanitizer */
+#if __has_attribute(no_sanitize)
+#define __nosanitizeaddress	__attribute__((no_sanitize("address")))
+#else
+#define __nosanitizeaddress
+#endif
+
 /* Guard variables and structure members by lock. */
 #define	__guarded_by(x)		__lock_annotate(guarded_by(x))
 #define	__pt_guarded_by(x)	__lock_annotate(pt_guarded_by(x))

Modified: head/sys/sys/linker_set.h
==============================================================================
--- head/sys/sys/linker_set.h	Tue Nov 19 13:28:59 2019	(r354853)
+++ head/sys/sys/linker_set.h	Tue Nov 19 14:46:28 2019	(r354854)
@@ -61,6 +61,7 @@
 	__GLOBL(__CONCAT(__stop_set_,set));		\
 	static void const * qv				\
 	__set_##set##_sym_##sym __section("set_" #set)	\
+	__nosanitizeaddress				\
 	__used = &(sym)
 #define __MAKE_SET(set, sym)	__MAKE_SET_QV(set, sym, __MAKE_SET_CONST)
 #else /* !__GNUCLIKE___SECTION */