GNU C Library master sources branch master updated. glibc-2.18-659-g69a17d9

[ppluzhnikov at sourceware dot org]

This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GNU C Library master sources".

The branch, master has been updated
       via  69a17d9d245dc3551792e95e1823cc2d877592f3 (commit)
      from  a588438951a271ca10623fb8c7e25693c7ebea67 (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=69a17d9d245dc3551792e95e1823cc2d877592f3

commit 69a17d9d245dc3551792e95e1823cc2d877592f3
Author: Paul Pluzhnikov <ppluzhnikov@google.com>
Date:   Wed Dec 18 15:07:11 2013 -0800

    Patch [1/4] async-signal safe TLS.
    
    2013-12-18  Andrew Hunter  <ahh@google.com>
    
    	* sysdeps/generic/ldsodefs.h (_dl_mask_all_signals): New prototype.
    	(_dl_unmask_signals): Likewise.
    	* sysdeps/mach/hurd/dl-sysdep.h (_dl_mask_all_signals): New stub.
    	(_dl_unmask_all_signals): Likewise.
    	* sysdeps/unix/sysv/linux/dl-sysdep.h (_dl_mask_all_signals): New prototype.
    	(_dl_unmask_all_signals): Likewise.
    	* sysdeps/unix/sysv/linux/dl-sysdep.c (_dl_mask_all_signals): New function.
    	(_dl_unmask_signals): Likewise.

diff --git a/ChangeLog b/ChangeLog
index 173c280..126c92e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2013-12-18  Andrew Hunter  <ahh@google.com>
+
+	* sysdeps/generic/ldsodefs.h (_dl_mask_all_signals): New prototype.
+	(_dl_unmask_signals): Likewise.
+	* sysdeps/mach/hurd/dl-sysdep.h (_dl_mask_all_signals): New stub.
+	(_dl_unmask_all_signals): Likewise.
+	* sysdeps/unix/sysv/linux/dl-sysdep.h (_dl_mask_all_signals): New prototype.
+	(_dl_unmask_all_signals): Likewise.
+	* sysdeps/unix/sysv/linux/dl-sysdep.c (_dl_mask_all_signals): New function.
+	(_dl_unmask_signals): Likewise.
+
 2013-12-18  Brooks Moses  <bmoses@google.com>
 
 	[BZ #15846]
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index 146aca4..e919e41 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -234,6 +234,11 @@ extern int _dl_name_match_p (const char *__name, const struct link_map *__map)
 extern unsigned long int _dl_higher_prime_number (unsigned long int n)
      internal_function;
 
+/* Mask every signal, returning the previous sigmask in OLD.  */
+extern void _dl_mask_all_signals (sigset_t *old) internal_function;
+/* Undo _dl_mask_all_signals.  */
+extern void _dl_unmask_signals (sigset_t *old) internal_function;
+
 /* Function used as argument for `_dl_receive_error' function.  The
    arguments are the error code, error string, and the objname the
    error occurred in.  */
diff --git a/sysdeps/mach/hurd/dl-sysdep.h b/sysdeps/mach/hurd/dl-sysdep.h
index 52563b0..0e7cac4 100644
--- a/sysdeps/mach/hurd/dl-sysdep.h
+++ b/sysdeps/mach/hurd/dl-sysdep.h
@@ -29,3 +29,10 @@
 # define DL_ARGV_NOT_RELRO 1
 # define LIBC_STACK_END_NOT_RELRO 1
 #endif
+
+#include <signal.h>
+inline void _dl_mask_all_signals (sigset_t *) internal_function;
+inline void _dl_mask_all_signals (sigset_t *) { }
+
+inline void _dl_unmask_all_signals (sigset_t *) internal_function;
+inline void _dl_unmask_all_signals (sigset_t *) { }
diff --git a/sysdeps/unix/sysv/linux/dl-sysdep.c b/sysdeps/unix/sysv/linux/dl-sysdep.c
index e80cb8d..4b837ac 100644
--- a/sysdeps/unix/sysv/linux/dl-sysdep.c
+++ b/sysdeps/unix/sysv/linux/dl-sysdep.c
@@ -19,6 +19,7 @@
 /* Linux needs some special initialization, but otherwise uses
    the generic dynamic linker system interface code.  */
 
+#include <assert.h>
 #include <string.h>
 #include <fcntl.h>
 #include <unistd.h>
@@ -130,3 +131,48 @@ _dl_discover_osversion (void)
 
   return version;
 }
+
+/* Mask every signal, returning the previous sigmask in OLD.  */
+void
+internal_function
+_dl_mask_all_signals (sigset_t *old)
+{
+  int ret;
+  sigset_t new;
+
+  sigfillset (&new);
+
+  /* This function serves as a replacement to pthread_sigmask, which
+     isn't available from within the dynamic linker since it would require
+     linking with libpthread. We duplicate some of the functionality here
+     to avoid requiring libpthread.  This isn't quite identical to
+     pthread_sigmask in that we do not mask internal signals used for
+     cancellation and setxid handling. This disables asynchronous
+     cancellation for the duration the signals are disabled, but it's a
+     small window, and prevents any problems with the use of TLS variables
+     in the signal handlers that would have executed.  */
+
+  /* It's very important we don't touch errno here, as that's TLS; since this
+     gets called from get_tls_addr we might end up recursing.  */
+
+  INTERNAL_SYSCALL_DECL (err);
+
+  ret = INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, &new, old,
+			  _NSIG / 8);
+
+  assert (ret == 0);
+}
+
+/* Return sigmask to what it was before a call to _dl_mask_all_signals.  */
+void
+internal_function
+_dl_unmask_signals (sigset_t *old)
+{
+  int ret;
+  INTERNAL_SYSCALL_DECL (err);
+
+  ret = INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_SETMASK, old, NULL,
+			  _NSIG / 8);
+
+  assert (ret == 0);
+}
diff --git a/sysdeps/unix/sysv/linux/dl-sysdep.h b/sysdeps/unix/sysv/linux/dl-sysdep.h
index e1eab09..0fe1e1c 100644
--- a/sysdeps/unix/sysv/linux/dl-sysdep.h
+++ b/sysdeps/unix/sysv/linux/dl-sysdep.h
@@ -30,4 +30,8 @@
 /* Get version of the OS.  */
 extern int _dl_discover_osversion (void) attribute_hidden;
 # define HAVE_DL_DISCOVER_OSVERSION	1
+
+#include <signal.h>
+void _dl_mask_all_signals (sigset_t *) internal_function;
+void _dl_unmask_all_signals (sigset_t *) internal_function;
 #endif

-----------------------------------------------------------------------

Summary of changes:
 ChangeLog                           |   11 ++++++++
 sysdeps/generic/ldsodefs.h          |    5 ++++
 sysdeps/mach/hurd/dl-sysdep.h       |    7 +++++
 sysdeps/unix/sysv/linux/dl-sysdep.c |   46 +++++++++++++++++++++++++++++++++++
 sysdeps/unix/sysv/linux/dl-sysdep.h |    4 +++
 5 files changed, 73 insertions(+), 0 deletions(-)


hooks/post-receive
-- 
GNU C Library master sources