Calling fswait can cause the kernel to crash.

[mxlgv]

Here is the code that causes the kernel to crash:

#include <sys/fswait.h>

int main(void)
{
    int fds[2];
    fswait(-1, fds);

    return 0;
}

Fix please.

[klange]

Sounds like this is a running theme - maybe we should collect as many instances of these unintended uses of signed values as we can in one place?

Should be fixed with 534aca2

[mxlgv]

Fine. The next time I find more such problems, I will issue a common issue for them.
Or you can create an issue now and move the found similar issues there.