prevent CNAME/PTR parsing from reading data past the response end

[musl] / src / signal / sigtimedwait.c

diff --git a/src/signal/sigtimedwait.c b/src/signal/sigtimedwait.c
index 93f31a7..1287174 100644 (file)
--- a/src/signal/sigtimedwait.c
+++ b/src/signal/sigtimedwait.c
@@ -1,15 +1,32 @@
 #include <signal.h>
 #include <errno.h>
 #include "syscall.h"
-#include "libc.h"
 
-int sigtimedwait(const sigset_t *mask, siginfo_t *si, const struct timespec *timeout)
+#define IS32BIT(x) !((x)+0x80000000ULL>>32)
+#define CLAMP(x) (int)(IS32BIT(x) ? (x) : 0x7fffffffU+((0ULL+(x))>>63))
+
+static int do_sigtimedwait(const sigset_t *restrict mask, siginfo_t *restrict si, const struct timespec *restrict ts)
+{
+#ifdef SYS_rt_sigtimedwait_time64
+       time_t s = ts ? ts->tv_sec : 0;
+       long ns = ts ? ts->tv_nsec : 0;
+       int r = -ENOSYS;
+       if (SYS_rt_sigtimedwait == SYS_rt_sigtimedwait_time64 || !IS32BIT(s))
+               r = __syscall_cp(SYS_rt_sigtimedwait_time64, mask, si,
+                       ts ? ((long long[]){s, ns}) : 0, _NSIG/8);
+       if (SYS_rt_sigtimedwait == SYS_rt_sigtimedwait_time64 || r!=-ENOSYS)
+               return r;
+       return __syscall_cp(SYS_rt_sigtimedwait, mask, si,
+               ts ? ((long[]){CLAMP(s), ns}) : 0, _NSIG/8);;
+#else
+       return __syscall_cp(SYS_rt_sigtimedwait, mask, si, ts, _NSIG/8);
+#endif
+}
+
+int sigtimedwait(const sigset_t *restrict mask, siginfo_t *restrict si, const struct timespec *restrict timeout)
 {
        int ret;
-       CANCELPT_BEGIN;
-       do {
-               ret = syscall4(__NR_rt_sigtimedwait, (long)mask, (long)si, (long)timeout, SYSCALL_SIGSET_SIZE);
-       } while (ret<0 && errno==EINTR);
-       CANCELPT_END;
-       return ret;
+       do ret = do_sigtimedwait(mask, si, timeout);
+       while (ret==-EINTR);
+       return __syscall_ret(ret);
 }