diff --git a/arch/x86/kernel/ioport.c b/arch/x86/kernel/ioport.c index be72d809bce7..50e5e4a31c85 100644 --- a/arch/x86/kernel/ioport.c +++ b/arch/x86/kernel/ioport.c @@ -113,40 +113,42 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on) * on system-call entry - see also fork() and the signal handling * code. */ +static int do_iopl(unsigned int level, struct pt_regs *regs) +{ + unsigned int old = (regs->flags >> 12) & 3; + + if (level > 3) + return -EINVAL; + /* Trying to gain more privileges? */ + if (level > old) { + if (!capable(CAP_SYS_RAWIO)) + return -EPERM; + } + regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12); + + return 0; +} + #ifdef CONFIG_X86_32 asmlinkage long sys_iopl(unsigned long regsp) { struct pt_regs *regs = (struct pt_regs *)®sp; unsigned int level = regs->bx; - unsigned int old = (regs->flags >> 12) & 3; struct thread_struct *t = ¤t->thread; + int rc; + + rc = do_iopl(level, regs); + if (rc < 0) + goto out; - if (level > 3) - return -EINVAL; - /* Trying to gain more privileges? */ - if (level > old) { - if (!capable(CAP_SYS_RAWIO)) - return -EPERM; - } t->iopl = level << 12; - regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12); set_iopl_mask(t->iopl); - return 0; +out: + return rc; } #else asmlinkage long sys_iopl(unsigned int level, struct pt_regs *regs) { - unsigned int old = (regs->flags >> 12) & 3; - - if (level > 3) - return -EINVAL; - /* Trying to gain more privileges? */ - if (level > old) { - if (!capable(CAP_SYS_RAWIO)) - return -EPERM; - } - regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12); - - return 0; + return do_iopl(level, regs); } #endif