From 327ae2570744dabf7f065a6b529d16cc22438603 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Fri, 17 Oct 2014 13:40:46 -0700 Subject: NPTL: Conditionalize more uses of SIGCANCEL and SIGSETXID. --- ChangeLog | 11 +++++++++++ nptl/allocatestack.c | 3 +++ nptl/nptl-init.c | 21 +++++++++++++++++---- nptl/pthread_create.c | 2 ++ 4 files changed, 33 insertions(+), 4 deletions(-) diff --git a/ChangeLog b/ChangeLog index 502bd42136..51f07f8517 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,16 @@ 2014-10-17 Roland McGrath + * nptl/nptl-init.c (sighandler_setxid, __xidcmd): Make definitions + conditional on [SIGSETXID]. + (sigcancel_handler): Make definition conditional on [SIGCANCEL]. + (__pthread_initialize_minimal_internal): Set up SIGCANCEL only if it + is defined. Likewise for SIGSETXID. + * nptl/allocatestack.c (setxid_mark_thread, setxid_unmark_thread): + Conditionalize definitions on [SIGSETXID]. + (setxid_signal_thread, __nptl_setxid_error, __nptl_setxid): Likewise. + * nptl/pthread_create.c (start_thread): Conditionalize SIGCANCEL + unblocking on [SIGCANCEL]. + * nptl/nptl-init.c (__nptl_set_robust): Conditionalize body on [__NR_set_robust_list]. diff --git a/nptl/allocatestack.c b/nptl/allocatestack.c index d95ffe9d36..b19d9b3e95 100644 --- a/nptl/allocatestack.c +++ b/nptl/allocatestack.c @@ -978,6 +978,7 @@ __find_thread_by_id (pid_t tid) #endif +#ifdef SIGSETXID static void internal_function setxid_mark_thread (struct xid_command *cmdp, struct pthread *t) @@ -1185,6 +1186,8 @@ __nptl_setxid (struct xid_command *cmdp) lll_unlock (stack_cache_lock, LLL_PRIVATE); return result; } +#endif /* SIGSETXID. */ + static inline void __attribute__((always_inline)) init_one_static_tls (struct pthread *curp, struct link_map *map) diff --git a/nptl/nptl-init.c b/nptl/nptl-init.c index 44223a7a41..d8154c4101 100644 --- a/nptl/nptl-init.c +++ b/nptl/nptl-init.c @@ -170,6 +170,7 @@ __nptl_set_robust (struct pthread *self) } +#ifdef SIGCANCEL /* For asynchronous cancellation we use a signal. This is the handler. */ static void sigcancel_handler (int sig, siginfo_t *si, void *ctx) @@ -221,8 +222,10 @@ sigcancel_handler (int sig, siginfo_t *si, void *ctx) oldval = curval; } } +#endif +#ifdef SIGSETXID struct xid_command *__xidcmd attribute_hidden; /* We use the SIGSETXID signal in the setuid, setgid, etc. implementations to @@ -273,6 +276,7 @@ sighandler_setxid (int sig, siginfo_t *si, void *ctx) if (atomic_decrement_val (&__xidcmd->cntr) == 0) lll_futex_wake (&__xidcmd->cntr, 1, LLL_PRIVATE); } +#endif /* When using __thread for this, we do it in libc so as not @@ -372,29 +376,38 @@ __pthread_initialize_minimal_internal (void) had to set __nptl_initial_report_events. Propagate its setting. */ THREAD_SETMEM (pd, report_events, __nptl_initial_report_events); +#if defined SIGCANCEL || defined SIGSETXID + struct sigaction sa; + __sigemptyset (&sa.sa_mask); + +# ifdef SIGCANCEL /* Install the cancellation signal handler. If for some reason we cannot install the handler we do not abort. Maybe we should, but it is only asynchronous cancellation which is affected. */ - struct sigaction sa; sa.sa_sigaction = sigcancel_handler; sa.sa_flags = SA_SIGINFO; - __sigemptyset (&sa.sa_mask); - (void) __libc_sigaction (SIGCANCEL, &sa, NULL); +# endif +# ifdef SIGSETXID /* Install the handle to change the threads' uid/gid. */ sa.sa_sigaction = sighandler_setxid; sa.sa_flags = SA_SIGINFO | SA_RESTART; - (void) __libc_sigaction (SIGSETXID, &sa, NULL); +# endif /* The parent process might have left the signals blocked. Just in case, unblock it. We reuse the signal mask in the sigaction structure. It is already cleared. */ +# ifdef SIGCANCEL __sigaddset (&sa.sa_mask, SIGCANCEL); +# endif +# ifdef SIGSETXID __sigaddset (&sa.sa_mask, SIGSETXID); +# endif (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &sa.sa_mask, NULL, _NSIG / 8); +#endif /* Get the size of the static and alignment requirements for the TLS block. */ diff --git a/nptl/pthread_create.c b/nptl/pthread_create.c index b9af010767..0055634cd3 100644 --- a/nptl/pthread_create.c +++ b/nptl/pthread_create.c @@ -263,6 +263,7 @@ start_thread (void *arg) } #endif +#ifdef SIGCANCEL /* If the parent was running cancellation handlers while creating the thread the new thread inherited the signal mask. Reset the cancellation signal mask. */ @@ -275,6 +276,7 @@ start_thread (void *arg) (void) INTERNAL_SYSCALL (rt_sigprocmask, err, 4, SIG_UNBLOCK, &mask, NULL, _NSIG / 8); } +#endif /* This is where the try/finally block should be created. For compilers without that support we do use setjmp. */ -- cgit v1.2.3