always block signals in pthread_exit before decrementing thread count

[musl] / src / thread / pthread_create.c

diff --git a/src/thread/pthread_create.c b/src/thread/pthread_create.c
index 059c20e..0cd2d6c 100644 (file)
--- a/src/thread/pthread_create.c
+++ b/src/thread/pthread_create.c
@@ -32,6 +32,8 @@ _Noreturn void pthread_exit(void *result)
        self->dead = 1;
        __unlock(self->killlock);
 
+       __syscall(SYS_rt_sigprocmask, SIG_BLOCK, SIGALL_SET, 0, _NSIG/8);
+
        do n = libc.threads_minus_1;
        while (n && a_cas(&libc.threads_minus_1, n, n-1)!=n);
        if (!n) exit(0);
@@ -39,8 +41,6 @@ _Noreturn void pthread_exit(void *result)
        if (self->detached && self->map_base) {
                if (self->detached == 2)
                        __syscall(SYS_set_tid_address, 0);
-               __syscall(SYS_rt_sigprocmask, SIG_BLOCK,
-                       SIGALL_SET, 0, _NSIG/8);
                __unmapself(self->map_base, self->map_size);
        }
 
@@ -101,7 +101,7 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
        int ret;
        size_t size, guard;
        struct pthread *self = pthread_self(), *new;
-       unsigned char *map = 0, *stack = 0, *tsd = 0;
+       unsigned char *map = 0, *stack = 0, *tsd = 0, *stack_limit;
        unsigned flags = 0x7d8f00;
        int do_sched = 0;
        pthread_attr_t attr = {0};
@@ -123,6 +123,7 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
                size_t need = libc.tls_size + __pthread_tsd_size;
                size = attr._a_stacksize + DEFAULT_STACK_SIZE;
                stack = (void *)(attr._a_stackaddr & -16);
+               stack_limit = (void *)(attr._a_stackaddr - size);
                /* Use application-provided stack for TLS only when
                 * it does not take more than ~12% or 2k of the
                 * application's stack space. */
@@ -152,12 +153,17 @@ int pthread_create(pthread_t *restrict res, const pthread_attr_t *restrict attrp
                        if (map == MAP_FAILED) goto fail;
                }
                tsd = map + size - __pthread_tsd_size;
-               if (!stack) stack = tsd - libc.tls_size;
+               if (!stack) {
+                       stack = tsd - libc.tls_size;
+                       stack_limit = map + guard;
+               }
        }
 
        new = __copy_tls(tsd - libc.tls_size);
        new->map_base = map;
        new->map_size = size;
+       new->stack = stack;
+       new->stack_size = stack - stack_limit;
        new->pid = self->pid;
        new->errno_ptr = &new->errno_val;
        new->start = entry;