From 16ab12a936ef96b25be7f5981c96548fa772f3df Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 30 Jan 2020 16:02:01 +0000 Subject: [PATCH] target/arm/arm-semi: Don't let the guest close stdin/stdout/stderr MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Reviewed-by: Alex Bennée Reviewed-by: Philippe Mathieu-Daudé Message-id: 20200124172954.28481-1-peter.maydell@linaro.org --- target/arm/arm-semi.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c index 788fe61b51..8718fd0194 100644 --- a/target/arm/arm-semi.c +++ b/target/arm/arm-semi.c @@ -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)); }