fix issue with longjmp out of signal handlers and cancellation

[musl] / src / thread / cancel_impl.c

diff --git a/src/thread/cancel_impl.c b/src/thread/cancel_impl.c
index 7652a7c..3bf1e39 100644 (file)
--- a/src/thread/cancel_impl.c
+++ b/src/thread/cancel_impl.c
@@ -14,19 +14,12 @@ long __syscall_cp_asm(volatile void *, long, long, long, long, long, long, long)
 long (__syscall_cp)(long nr, long u, long v, long w, long x, long y, long z)
 {
        pthread_t self;
-       uintptr_t old_sp, old_ip;
        long r;
 
        if (!libc.main_thread || (self = __pthread_self())->canceldisable)
                return __syscall(nr, u, v, w, x, y, z);
 
-       old_sp = self->cp_sp;
-       old_ip = self->cp_ip;
-       self->cp_sp = 0;
-       self->cp_ip = 0;
-       r = __syscall_cp_asm(&self->cp_sp, nr, u, v, w, x, y, z);
-       self->cp_ip = old_ip;
-       self->cp_sp = old_sp;
+       r = __syscall_cp_asm(&self->cancel, nr, u, v, w, x, y, z);
        if (r==-EINTR && nr!=SYS_close && self->cancel && !self->canceldisable)
                __cancel();
        return r;
@@ -42,14 +35,14 @@ static void cancel_handler(int sig, siginfo_t *si, void *ctx)
 {
        pthread_t self = __pthread_self();
        ucontext_t *uc = ctx;
-       uintptr_t sp = ((uintptr_t *)&uc->uc_mcontext)[CANCEL_REG_SP];
-       uintptr_t ip = ((uintptr_t *)&uc->uc_mcontext)[CANCEL_REG_IP];
+       const char *ip = ((char **)&uc->uc_mcontext)[CANCEL_REG_IP];
+       extern const char __cp_begin[1], __cp_end[1];
 
        if (!self->cancel || self->canceldisable) return;
 
        _sigaddset(&uc->uc_sigmask, SIGCANCEL);
 
-       if (self->cancelasync || sp == self->cp_sp && ip <= self->cp_ip) {
+       if (self->cancelasync || ip >= __cp_begin && ip < __cp_end) {
                self->canceldisable = 1;
                pthread_sigmask(SIG_SETMASK, &uc->uc_sigmask, 0);
                __cancel();