From c07ecc6866f8c5eb2e0b23ba20214000310355e0 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Mon, 7 Jan 2013 11:40:06 +0000 Subject: [PATCH] linux-user: correct reboot() According to man reboot(2), the 4th argument is only used with LINUX_REBOOT_CMD_RESTART2. In other cases, trying to convert the value can generate EFAULT. Signed-off-by: Laurent Vivier Reviewed-by: Peter Maydell --- linux-user/syscall.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 151f4f327..08538fc35 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -101,6 +101,7 @@ int __clone2(int (*fn)(void *), void *child_stack_base, #include #include #include +#include #include "linux_loop.h" #include "cpu-uname.h" @@ -6451,10 +6452,17 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1, break; #endif case TARGET_NR_reboot: - if (!(p = lock_user_string(arg4))) - goto efault; - ret = reboot(arg1, arg2, arg3, p); - unlock_user(p, arg4, 0); + if (arg3 == LINUX_REBOOT_CMD_RESTART2) { + /* arg4 must be ignored in all other cases */ + p = lock_user_string(arg4); + if (!p) { + goto efault; + } + ret = get_errno(reboot(arg1, arg2, arg3, p)); + unlock_user(p, arg4, 0); + } else { + ret = get_errno(reboot(arg1, arg2, arg3, NULL)); + } break; #ifdef TARGET_NR_readdir case TARGET_NR_readdir: -- 2.39.2