svn commit: r303685 - head/usr.bin/truss

[Baptiste Daroussin]

Author: bapt
Date: Tue Aug  2 22:47:06 2016
New Revision: 303685
URL: https://svnweb.freebsd.org/changeset/base/303685

Log:
  truss: fix uninitialized trussinfo->curthread in add_threads()/enter_syscall
  
  trussinfo->curthread must be initialized before calling enter_syscall(),
  it is used by t->proc->abi->fetch_args().
  Without that truss is segfaulting and the attached program also crash.
  
  Submitted by:	Nikita Kozlov (nikita at gandi.net)
  Reviewed by:	jhb
  MFC after:	3 days
  Differential Revision:	https://reviews.freebsd.org/D7399

Modified:
  head/usr.bin/truss/setup.c

Modified: head/usr.bin/truss/setup.c
==============================================================================
--- head/usr.bin/truss/setup.c	Tue Aug  2 22:33:29 2016	(r303684)
+++ head/usr.bin/truss/setup.c	Tue Aug  2 22:47:06 2016	(r303685)
@@ -223,8 +223,10 @@ add_threads(struct trussinfo *info, stru
 		t = new_thread(p, lwps[i]);
 		if (ptrace(PT_LWPINFO, lwps[i], (caddr_t)&pl, sizeof(pl)) == -1)
 			err(1, "ptrace(PT_LWPINFO)");
-		if (pl.pl_flags & PL_FLAG_SCE)
+		if (pl.pl_flags & PL_FLAG_SCE) {
+			info->curthread = t;
 			enter_syscall(info, t, &pl);
+		}
 	}
 	free(lwps);
 }