target/arm/arm-semi: Don't let the guest close stdin/stdout/stderr

The guest can use the semihosting API to open a handle
corresponding to QEMU's own stdin, stdout, or stderr.
When the guest closes this handle, we should not
close the underlying host stdin/stdout/stderr
the way we would do if the handle corresponded to
a host fd we'd opened on behalf of the guest in SYS_OPEN.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200124172954.28481-1-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2020-01-30 16:02:01 +00:00
parent ea4d7ab5d9
commit 16ab12a936

View File

@ -403,6 +403,15 @@ static uint32_t host_closefn(ARMCPU *cpu, GuestFD *gf)
{
CPUARMState *env = &cpu->env;
/*
* Only close the underlying host fd if it's one we opened on behalf
* of the guest in SYS_OPEN.
*/
if (gf->hostfd == STDIN_FILENO ||
gf->hostfd == STDOUT_FILENO ||
gf->hostfd == STDERR_FILENO) {
return 0;
}
return set_swi_errno(env, close(gf->hostfd));
}