diff options
Diffstat (limited to 'arch/x86/entry/vsyscall/vsyscall_64.c')
-rw-r--r-- | arch/x86/entry/vsyscall/vsyscall_64.c | 18 |
1 files changed, 11 insertions, 7 deletions
diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index 317be365bce3..70b7845434cb 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -127,6 +127,7 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) int vsyscall_nr, syscall_nr, tmp; int prev_sig_on_uaccess_err; long ret; + unsigned long orig_dx; /* * No point in checking CS -- the only way to get here is a user mode @@ -227,19 +228,22 @@ bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) ret = -EFAULT; switch (vsyscall_nr) { case 0: - ret = sys_gettimeofday( - (struct timeval __user *)regs->di, - (struct timezone __user *)regs->si); + /* this decodes regs->di and regs->si on its own */ + ret = __x64_sys_gettimeofday(regs); break; case 1: - ret = sys_time((time_t __user *)regs->di); + /* this decodes regs->di on its own */ + ret = __x64_sys_time(regs); break; case 2: - ret = sys_getcpu((unsigned __user *)regs->di, - (unsigned __user *)regs->si, - NULL); + /* while we could clobber regs->dx, we didn't in the past... */ + orig_dx = regs->dx; + regs->dx = 0; + /* this decodes regs->di, regs->si and regs->dx on its own */ + ret = __x64_sys_getcpu(regs); + regs->dx = orig_dx; break; } |