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authorAdhemerval Zanella <adhemerval.zanella@linaro.org>2016-08-20 11:23:08 -0300
committerAdhemerval Zanella <adhemerval.zanella@linaro.org>2016-09-15 11:14:25 -0300
commit91dd866ff1801b27e1db1e14a52eb89a213627e6 (patch)
tree05093e97e9c7ba82bc6ac393f27f96b27ecf6f93
parent980d25d53e748abd3365aeec0a1ccd1316b4e6d6 (diff)
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nptl: Set sem_open as a non cancellation point (BZ #15765)
This patch changes sem_open to not act as a cancellation point. Cancellation is disable at start and reenable in function exit. It fixes BZ #15765. Tested on x86_64 and i686. [BZ #15765] * nptl/Makefile (tests): Add tst-sem16. * nptl/tst-sem16.c: New file. * nptl/sem_open.c (sem_open): Disable asynchronous cancellation.
-rw-r--r--ChangeLog5
-rw-r--r--nptl/Makefile2
-rw-r--r--nptl/sem_open.c25
-rw-r--r--nptl/tst-sem16.c130
4 files changed, 157 insertions, 5 deletions
diff --git a/ChangeLog b/ChangeLog
index 6ad743a..1d3bc50 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
2016-09-15 Adhemerval Zanella <adhemerval.zanella@linaro.org>
+ [BZ #15765]
+ * nptl/Makefile (tests): Add tst-sem16.
+ * nptl/tst-sem16.c: New file.
+ * nptl/sem_open.c (sem_open): Disable asynchronous cancellation.
+
* nptl/sem_open.c (sem_open): Init pad value to 0.
* sysdeps/sparc/sparc32/sem_open.c: Remove file.
* sysdeps/sparc/sparc32/sparcv9/sem_open.c: Likewise.
diff --git a/nptl/Makefile b/nptl/Makefile
index e8de1bc..e9485df 100644
--- a/nptl/Makefile
+++ b/nptl/Makefile
@@ -246,7 +246,7 @@ tests = tst-typesizes \
tst-key1 tst-key2 tst-key3 tst-key4 \
tst-sem1 tst-sem2 tst-sem3 tst-sem4 tst-sem5 tst-sem6 tst-sem7 \
tst-sem8 tst-sem9 tst-sem10 tst-sem11 tst-sem12 tst-sem13 tst-sem14 \
- tst-sem15 \
+ tst-sem15 tst-sem16 \
tst-barrier1 tst-barrier2 tst-barrier3 tst-barrier4 tst-barrier5 \
tst-align tst-align3 \
tst-basic1 tst-basic2 tst-basic3 tst-basic4 tst-basic5 tst-basic6 \
diff --git a/nptl/sem_open.c b/nptl/sem_open.c
index 5b45fad..d108286 100644
--- a/nptl/sem_open.c
+++ b/nptl/sem_open.c
@@ -31,7 +31,7 @@
#include "semaphoreP.h"
#include <shm-directory.h>
#include <futex-internal.h>
-
+#include <libc-lock.h>
/* Comparison function for search of existing mapping. */
int
@@ -153,6 +153,13 @@ sem_open (const char *name, int oflag, ...)
/* Create the name of the final file in local variable SHM_NAME. */
SHM_GET_NAME (EINVAL, SEM_FAILED, SEM_SHM_PREFIX);
+ /* Disable asynchronous cancellation. */
+#ifdef __libc_ptf_call
+ int state;
+ __libc_ptf_call (__pthread_setcancelstate,
+ (PTHREAD_CANCEL_DISABLE, &state), 0);
+#endif
+
/* If the semaphore object has to exist simply open it. */
if ((oflag & O_CREAT) == 0 || (oflag & O_EXCL) == 0)
{
@@ -193,7 +200,8 @@ sem_open (const char *name, int oflag, ...)
if (value > SEM_VALUE_MAX)
{
__set_errno (EINVAL);
- return SEM_FAILED;
+ result = SEM_FAILED;
+ goto out;
}
/* Create the initial file content. */
@@ -233,7 +241,10 @@ sem_open (const char *name, int oflag, ...)
mode cannot later be set since then we cannot apply the
file create mask. */
if (__mktemp (tmpfname) == NULL)
- return SEM_FAILED;
+ {
+ result = SEM_FAILED;
+ goto out;
+ }
/* Open the file. Make sure we do not overwrite anything. */
fd = __libc_open (tmpfname, O_RDWR | O_CREAT | O_EXCL, mode);
@@ -247,7 +258,8 @@ sem_open (const char *name, int oflag, ...)
__set_errno (EAGAIN);
}
- return SEM_FAILED;
+ result = SEM_FAILED;
+ goto out;
}
/* We got a file. */
@@ -308,5 +320,10 @@ sem_open (const char *name, int oflag, ...)
errno = save;
}
+out:
+#ifdef __libc_ptf_call
+ __libc_ptf_call (__pthread_setcancelstate, (state, NULL), 0);
+#endif
+
return result;
}
diff --git a/nptl/tst-sem16.c b/nptl/tst-sem16.c
new file mode 100644
index 0000000..7006754
--- /dev/null
+++ b/nptl/tst-sem16.c
@@ -0,0 +1,130 @@
+/* Test for sem_open cancellation handling: BZ #15765.
+ Copyright (C) 2016 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 <pthread.h>
+#include <sys/mman.h>
+#include <semaphore.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <errno.h>
+#include <stdlib.h>
+
+static sem_t sem; /* Use to sync with thread start. */
+static const char pipe_name[] = "/glibc-tst-sem16";
+
+static void
+remove_sem (int status, void *arg)
+{
+ sem_unlink (arg);
+}
+
+static void *
+tf (void *arg)
+{
+ pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, 0);
+
+ if (sem_wait (&sem) != 0)
+ {
+ printf ("error: sem_wait failed: %m");
+ exit (1);
+ }
+
+ if (pthread_setcancelstate (PTHREAD_CANCEL_ENABLE, 0) != 0)
+ {
+ printf ("error: pthread_setcancelstate failed: %m");
+ exit (1);
+ }
+
+ /* Neither sem_unlink or sem_open should act on thread cancellation. */
+ sem_unlink (pipe_name);
+ on_exit (remove_sem, (void *) pipe_name);
+
+ sem_t *s = sem_open (pipe_name, O_CREAT, 0600, 1);
+ if (s == SEM_FAILED)
+ {
+ int exit_code;
+ if (errno == ENOSYS || errno == EACCES)
+ exit_code = 77;
+ else
+ exit_code = 1;
+ exit (exit_code);
+ }
+
+ if (pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, 0) != 0)
+ {
+ printf ("error: pthread_setcancelstate failed: %m");
+ exit (1);
+ }
+
+ if (sem_close (s) != 0)
+ {
+ printf ("error: sem_close failed: %m");
+ exit (1);
+ }
+
+ return NULL;
+}
+
+static int
+do_test (void)
+{
+ pthread_t td;
+
+ if (sem_init (&sem, 0, 0))
+ {
+ printf ("error: sem_init failed: %m\n");
+ exit (1);
+ }
+
+ if (pthread_create (&td, NULL, tf, NULL) != 0)
+ {
+ printf ("error: pthread_create failed: %m\n");
+ exit (1);
+ }
+
+ if (pthread_cancel (td) != 0)
+ {
+ printf ("error: pthread_cancel failed: %m\n");
+ exit (1);
+ }
+
+ if (sem_post (&sem) != 0)
+ {
+ printf ("error: sem_post failed: %m\n");
+ exit (1);
+ }
+
+ void *r;
+ if (pthread_join (td, &r) != 0)
+ {
+ printf ("error: pthread_join failed: %m\n");
+ exit (1);
+ }
+
+ if (r == PTHREAD_CANCELED)
+ {
+ puts ("error: pthread_join returned PTHREAD_CANCELED");
+ exit (1);
+ }
+
+ return 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include <test-skeleton.c>