From 4eaa960dbcd3fbd51047eacbbc20a9882a0eca63 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 19 May 2020 11:56:45 -0700 Subject: [PATCH] linux-user: Adjust guest page protection for the host MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Executable guest pages are never directly executed by the host, but do need to be readable for translation. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Peter Maydell Message-Id: <20200519185645.3915-3-richard.henderson@linaro.org> Signed-off-by: Laurent Vivier --- linux-user/mmap.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 46c7eeba9b..f261563420 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -76,8 +76,12 @@ static int validate_prot_to_pageflags(int *host_prot, int prot) * don't bother transforming guest bit to host bit. Any other * target-specific prot bits will not be understood by the host * and will need to be encoded into page_flags for qemu emulation. + * + * Pages that are executable by the guest will never be executed + * by the host, but the host will need to be able to read them. */ - *host_prot = prot & (PROT_READ | PROT_WRITE | PROT_EXEC); + *host_prot = (prot & (PROT_READ | PROT_WRITE)) + | (prot & PROT_EXEC ? PROT_READ : 0); return prot & ~valid ? 0 : page_flags; }