+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]
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. */
# 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 *) { }
/* 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>
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);
+}