S/390: Fix setcontext/swapcontext which are not restoring sigmask.

ChangeLog

@@ -1,3 +1,19 @@
+2015-03-12  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+	[BZ #18080]
+	* sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S
+	(__setcontext): Use SIG_SETMASK instead of SIG_BLOCK.
+	* sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S
+	(__setcontext): Likewise.
+	* sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S
+	(__swapcontext): Use SIG_SETMASK instead of SIG_BLOCK.
+	Call rt_sigprocmask syscall one time to set new signal mask
+	and retrieve the current signal mask instead of two calls.
+	* sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S
+	(__swapcontext): Likewise.
+	* stdlib/Makefile (tests): Add new testcase tst-setcontext2.
+	* stdlib/tst-setcontext2.c: New file.
+
 2015-03-12  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
 	* sysdeps/s390/fpu/libm-test-ulps: Regenerate.

NEWS

@@ -14,7 +14,7 @@ Version 2.22
   17792, 17836, 17912, 17916, 17932, 17944, 17949, 17964, 17965, 17967,
   17969, 17978, 17987, 17991, 17996, 17998, 17999, 18019, 18020, 18029,
   18030, 18032, 18036, 18038, 18039, 18042, 18043, 18046, 18047, 18068,
-  18093, 18104, 18110, 18111.
+  18080, 18093, 18104, 18110, 18111.
 
 * Character encoding and ctype tables were updated to Unicode 7.0.0, using
   new generator scripts contributed by Pravin Satpute and Mike FABIAN (Red

stdlib/Makefile

@@ -67,10 +67,10 @@ tests		:= tst-strtol tst-strtod testmb testrand testsort testdiv   \
 		   test-canon test-canon2 tst-strtoll tst-environ	    \
 		   tst-xpg-basename tst-random tst-random2 tst-bsearch	    \
 		   tst-limits tst-rand48 bug-strtod tst-setcontext          \
-		   test-a64l tst-qsort tst-system testmb2 bug-strtod2	    \
+		   tst-setcontext2 test-a64l tst-qsort tst-system testmb2   \
-		   tst-atof1 tst-atof2 tst-strtod2 tst-strtod3 tst-rand48-2 \
+		   bug-strtod2 tst-atof1 tst-atof2 tst-strtod2 tst-strtod3  \
-		   tst-makecontext tst-strtod4 tst-strtod5 tst-qsort2	    \
+		   tst-rand48-2 tst-makecontext tst-strtod4 tst-strtod5     \
-		   tst-makecontext2 tst-strtod6 tst-unsetenv1		    \
+		   tst-qsort2 tst-makecontext2 tst-strtod6 tst-unsetenv1    \
 		   tst-makecontext3 bug-getcontext bug-fmtmsg1		    \
 		   tst-secure-getenv tst-strtod-overflow tst-strtod-round   \
 		   tst-tininess tst-strtod-underflow tst-tls-atexit

stdlib/tst-setcontext2.c

@@ -0,0 +1,230 @@
+/* Testcase checks, if setcontext(), swapcontext() restores signal-mask
+   and if pending signals are delivered after those calls.
+   Copyright (C) 2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <ucontext.h>
+#include <unistd.h>
+
+volatile int global;
+volatile sig_atomic_t handlerCalled;
+
+static void
+check (const char *funcName)
+{
+  sigset_t set;
+
+  /* check if SIGUSR2 is unblocked after setcontext-call.  */
+  sigprocmask (SIG_BLOCK, NULL, &set);
+
+  if (sigismember (&set, SIGUSR2) != 0)
+    {
+      printf ("FAIL: SIGUSR2 is blocked after %s.\n", funcName);
+      exit (1);
+    }
+
+  if (sigismember (&set, SIGUSR1) != 1)
+    {
+      printf ("FAIL: SIGUSR1 is not blocked after %s.\n", funcName);
+      exit (1);
+    }
+}
+
+static void
+signalmask (int how, int signum)
+{
+  sigset_t set;
+  sigemptyset (&set);
+  sigaddset (&set, signum);
+  if (sigprocmask (how, &set, NULL) != 0)
+    {
+      printf ("FAIL: sigprocmaks (%d, %d, NULL): %m\n", how, signum);
+      exit (1);
+    }
+}
+
+static void
+signalpending (int signum, const char *msg)
+{
+  sigset_t set;
+  sigemptyset (&set);
+  if (sigpending (&set) != 0)
+    {
+      printf ("FAIL: sigpending: %m\n");
+      exit (1);
+    }
+  if (sigismember (&set, SIGUSR2) != 1)
+    {
+      printf ("FAIL: Signal %d is not pending %s\n", signum, msg);
+      exit (1);
+    }
+}
+
+static void
+handler (int __attribute__ ((unused)) signum)
+{
+  handlerCalled ++;
+}
+
+static int
+do_test (void)
+{
+  ucontext_t ctx, oldctx;
+  struct sigaction action;
+  pid_t pid;
+
+  pid = getpid ();
+
+  /* unblock SIGUSR2 */
+  signalmask (SIG_UNBLOCK, SIGUSR2);
+
+  /* block SIGUSR1 */
+  signalmask (SIG_BLOCK, SIGUSR1);
+
+  /* register handler for SIGUSR2  */
+  action.sa_flags = 0;
+  action.sa_handler = handler;
+  sigemptyset (&action.sa_mask);
+  sigaction (SIGUSR2, &action, NULL);
+
+  if (getcontext (&ctx) != 0)
+    {
+      printf ("FAIL: getcontext: %m\n");
+      exit (1);
+    }
+
+  global++;
+
+  if (global == 1)
+    {
+      puts ("after getcontext");
+
+      /* block SIGUSR2  */
+      signalmask (SIG_BLOCK, SIGUSR2);
+
+      /* send SIGUSR2 to me  */
+      handlerCalled = 0;
+      kill (pid, SIGUSR2);
+
+      /* was SIGUSR2 handler called?  */
+      if (handlerCalled != 0)
+	{
+	  puts ("FAIL: signal handler was called, but signal was blocked.");
+	  exit (1);
+	}
+
+      /* is SIGUSR2 pending?  */
+      signalpending (SIGUSR2, "before setcontext");
+
+      /* SIGUSR2 will be unblocked by setcontext-call.  */
+      if (setcontext (&ctx) != 0)
+	{
+	  printf ("FAIL: setcontext: %m\n");
+	  exit (1);
+	}
+    }
+  else if (global == 2)
+    {
+      puts ("after setcontext");
+
+      /* check SIGUSR1/2  */
+      check ("setcontext");
+
+      /* was SIGUSR2 handler called? */
+      if (handlerCalled != 1)
+	{
+	  puts ("FAIL: signal handler was not called after setcontext.");
+	  exit (1);
+	}
+
+      /* block SIGUSR2 */
+      signalmask (SIG_BLOCK, SIGUSR2);
+
+      /* send SIGUSR2 to me  */
+      handlerCalled = 0;
+      kill (pid, SIGUSR2);
+
+      /* was SIGUSR2 handler called?  */
+      if (handlerCalled != 0)
+	{
+	  puts ("FAIL: signal handler was called, but signal was blocked.");
+	  exit (1);
+	}
+
+      /* is SIGUSR2 pending?  */
+      signalpending (SIGUSR2, "before swapcontext");
+
+      if (swapcontext (&oldctx, &ctx) != 0)
+	{
+	  printf ("FAIL: swapcontext: %m\n");
+	  exit (1);
+	}
+
+      puts ("after returned from swapcontext");
+
+      if (global != 3)
+	{
+	  puts ("FAIL: returned from swapcontext without ctx-context called.");
+	  exit (1);
+	}
+
+      puts ("test succeeded");
+      return 0;
+    }
+  else if ( global != 3 )
+    {
+      puts ("FAIL: 'global' not incremented three times");
+      exit (1);
+    }
+
+  puts ("after swapcontext");
+  /* check SIGUSR1/2  */
+  check ("swapcontext");
+
+  /* was SIGUSR2 handler called? */
+  if (handlerCalled != 1)
+    {
+      puts ("FAIL: signal handler was not called after swapcontext.");
+      exit (1);
+    }
+
+  /* check sigmask in old context of swapcontext-call  */
+  if (sigismember (&oldctx.uc_sigmask, SIGUSR2) != 1)
+    {
+      puts ("FAIL: SIGUSR2 is not blocked in oldctx.uc_sigmask.");
+      exit (1);
+    }
+
+  if (sigismember (&oldctx.uc_sigmask, SIGUSR1) != 1)
+    {
+      puts ("FAIL: SIGUSR1 is not blocked in oldctx.uc_sigmaks.");
+      exit (1);
+    }
+
+  /* change to old context, which was gathered by swapcontext() call.  */
+  setcontext (&oldctx);
+
+  puts ("FAIL: returned from setcontext (&oldctx)");
+  exit (1);
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"

sysdeps/unix/sysv/linux/s390/s390-32/setcontext.S

@@ -34,7 +34,7 @@ ENTRY(__setcontext)
 	lr	%r1,%r2
 
 	/* rt_sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL, sigsetsize).  */
-	la      %r2,SIG_BLOCK
+	la      %r2,SIG_SETMASK
 	la	%r3,SC_MASK(%r1)
 	slr	%r4,%r4
 	lhi	%r5,_NSIG8

sysdeps/unix/sysv/linux/s390/s390-32/swapcontext.S

@@ -24,7 +24,7 @@
 /*  __swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
 
   Saves the machine context in oucp such that when it is activated,
-  it appears as if __swapcontextt() returned again, restores the
+  it appears as if __swapcontext() returned again, restores the
   machine context in ucp and thereby resumes execution in that
   context.
 
@@ -39,13 +39,6 @@ ENTRY(__swapcontext)
 	lr	%r1,%r2
 	lr      %r0,%r3
 
-	/* sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask).  */
-	la      %r2,SIG_BLOCK
-	slr	%r3,%r3
-	la	%r4,SC_MASK(%r1)
-	lhi	%r5,_NSIG8
-	svc	SYS_ify(rt_sigprocmask)
-
 	/* Store fpu context.  */
 	stfpc   SC_FPC(%r1)
 	std     %f0,SC_FPRS(%r1)
@@ -74,11 +67,12 @@ ENTRY(__swapcontext)
 	/* Store general purpose registers.  */
 	stm     %r0,%r15,SC_GPRS(%r1)
 
-	/* sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL).  */
+	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask,
-	la      %r2,SIG_BLOCK
+	   sigsetsize).  */
+	la      %r2,SIG_SETMASK
 	lr	%r5,%r0
 	la	%r3,SC_MASK(%r5)
-	slr	%r4,%r4
+	la	%r4,SC_MASK(%r1)
 	lhi	%r5,_NSIG8
 	svc	SYS_ify(rt_sigprocmask)
 

sysdeps/unix/sysv/linux/s390/s390-64/setcontext.S

@@ -34,7 +34,7 @@ ENTRY(__setcontext)
 	lgr	%r1,%r2
 
 	/* sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL).  */
-	la      %r2,SIG_BLOCK
+	la      %r2,SIG_SETMASK
 	la	%r3,SC_MASK(%r1)
 	slgr	%r4,%r4
 	lghi	%r5,_NSIG8

sysdeps/unix/sysv/linux/s390/s390-64/swapcontext.S

@@ -24,7 +24,7 @@
 /*  __swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
 
   Saves the machine context in oucp such that when it is activated,
-  it appears as if __swapcontextt() returned again, restores the
+  it appears as if __swapcontext() returned again, restores the
   machine context in ucp and thereby resumes execution in that
   context.
 
@@ -39,13 +39,6 @@ ENTRY(__swapcontext)
 	lgr	%r1,%r2
 	lgr     %r0,%r3
 
-	/* sigprocmask (SIG_BLOCK, NULL, &sc->sc_mask).  */
-	la      %r2,SIG_BLOCK
-	slgr	%r3,%r3
-	la	%r4,SC_MASK(%r1)
-	lghi	%r5,_NSIG8
-	svc	SYS_ify(rt_sigprocmask)
-
 	/* Store fpu context.  */
 	stfpc   SC_FPC(%r1)
 	std     %f0,SC_FPRS(%r1)
@@ -74,12 +67,13 @@ ENTRY(__swapcontext)
 	/* Store general purpose registers.  */
 	stmg    %r0,%r15,SC_GPRS(%r1)
 
-	/* rt_sigprocmask (SIG_SETMASK, &sc->sc_mask, NULL, sigsetsize).  */
+	/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask,
-	la      %r2,SIG_BLOCK
+	   sigsetsize).  */
+	la      %r2,SIG_SETMASK
 	lgr	%r5,%r0
 	la	%r3,SC_MASK(%r5)
+	la	%r4,SC_MASK(%r1)
 	lghi	%r5,_NSIG8
-	slgr	%r4,%r4
 	svc	SYS_ify(rt_sigprocmask)
 
 	/* Load fpu context.  */