From 90c0f080fe6fdd8b18691e6e38c853c8a996ad92 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 27 May 2016 15:52:01 +0100 Subject: [PATCH] linux-user: Avoid possible misalignment in target_to_host_siginfo() Reimplement target_to_host_siginfo() to use __get_user(), which handles possibly misaligned source guest structures correctly. Reviewed-by: Laurent Vivier Signed-off-by: Peter Maydell Signed-off-by: Riku Voipio --- linux-user/signal.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/linux-user/signal.c b/linux-user/signal.c index 8ea0cbf0e6..61c1145446 100644 --- a/linux-user/signal.c +++ b/linux-user/signal.c @@ -408,13 +408,18 @@ void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info) /* XXX: find a solution for 64 bit (additional malloced data is needed) */ void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo) { - info->si_signo = tswap32(tinfo->si_signo); - info->si_errno = tswap32(tinfo->si_errno); - info->si_code = tswap32(tinfo->si_code); - info->si_pid = tswap32(tinfo->_sifields._rt._pid); - info->si_uid = tswap32(tinfo->_sifields._rt._uid); - info->si_value.sival_ptr = - (void *)(long)tswapal(tinfo->_sifields._rt._sigval.sival_ptr); + /* This conversion is used only for the rt_sigqueueinfo syscall, + * and so we know that the _rt fields are the valid ones. + */ + abi_ulong sival_ptr; + + __get_user(info->si_signo, &tinfo->si_signo); + __get_user(info->si_errno, &tinfo->si_errno); + __get_user(info->si_code, &tinfo->si_code); + __get_user(info->si_pid, &tinfo->_sifields._rt._pid); + __get_user(info->si_uid, &tinfo->_sifields._rt._uid); + __get_user(sival_ptr, &tinfo->_sifields._rt._sigval.sival_ptr); + info->si_value.sival_ptr = (void *)(long)sival_ptr; } static int fatal_signal (int sig)