svn commit: r301525 - vendor-sys/illumos/dist/uts/common/dtrace

[Mark Johnston]

Author: markj
Date: Mon Jun  6 22:07:55 2016
New Revision: 301525
URL: https://svnweb.freebsd.org/changeset/base/301525

Log:
  7033 ustack helper should fault on bad return values
  
  Reviewed by: Patrick Mooney <patrick.mooney at joyent.com>
  Reviewed by: Bryan Cantrill <bryan at joyent.com>
  Approved by: Matthew Ahrens <mahrens at delphix.com>
  Author: Alex Wilson <alex.wilson at joyent.com>
  
  illumos/illumos-gate at a2f72b65ebc430aaf277ad797e554bb4deba9b95

Modified:
  vendor-sys/illumos/dist/uts/common/dtrace/dtrace.c

Modified: vendor-sys/illumos/dist/uts/common/dtrace/dtrace.c
==============================================================================
--- vendor-sys/illumos/dist/uts/common/dtrace/dtrace.c	Mon Jun  6 22:06:45 2016	(r301524)
+++ vendor-sys/illumos/dist/uts/common/dtrace/dtrace.c	Mon Jun  6 22:07:55 2016	(r301525)
@@ -6526,6 +6526,7 @@ dtrace_action_ustack(dtrace_mstate_t *ms
 	uint64_t *pcs = &buf[1], *fps;
 	char *str = (char *)&pcs[nframes];
 	int size, offs = 0, i, j;
+	size_t rem;
 	uintptr_t old = mstate->dtms_scratch_ptr, saved;
 	uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
 	char *sym;
@@ -6597,12 +6598,18 @@ dtrace_action_ustack(dtrace_mstate_t *ms
 			continue;
 		}
 
+		if (!dtrace_strcanload((uintptr_t)sym, strsize, &rem, mstate,
+		    &(state->dts_vstate))) {
+			str[offs++] = '\0';
+			continue;
+		}
+
 		DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
 
 		/*
 		 * Now copy in the string that the helper returned to us.
 		 */
-		for (j = 0; offs + j < strsize; j++) {
+		for (j = 0; offs + j < strsize && j < rem; j++) {
 			if ((str[offs + j] = sym[j]) == '\0')
 				break;
 		}