diff options
Diffstat (limited to 'arch/sparc/kernel/signal_64.c')
| -rw-r--r-- | arch/sparc/kernel/signal_64.c | 31 |
1 files changed, 20 insertions, 11 deletions
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index 39aaec173f66..5ee930c48f4c 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -234,6 +234,17 @@ do_sigsegv: goto out; } +/* Checks if the fp is valid. We always build rt signal frames which + * are 16-byte aligned, therefore we can always enforce that the + * restore frame has that property as well. + */ +static bool invalid_frame_pointer(void __user *fp) +{ + if (((unsigned long) fp) & 15) + return true; + return false; +} + struct rt_signal_frame { struct sparc_stackf ss; siginfo_t info; @@ -246,8 +257,8 @@ struct rt_signal_frame { void do_rt_sigreturn(struct pt_regs *regs) { + unsigned long tpc, tnpc, tstate, ufp; struct rt_signal_frame __user *sf; - unsigned long tpc, tnpc, tstate; __siginfo_fpu_t __user *fpu_save; __siginfo_rwin_t __user *rwin_save; sigset_t set; @@ -261,10 +272,16 @@ void do_rt_sigreturn(struct pt_regs *regs) (regs->u_regs [UREG_FP] + STACK_BIAS); /* 1. Make sure we are not getting garbage from the user */ - if (((unsigned long) sf) & 3) + if (invalid_frame_pointer(sf)) + goto segv; + + if (get_user(ufp, &sf->regs.u_regs[UREG_FP])) goto segv; - err = get_user(tpc, &sf->regs.tpc); + if ((ufp + STACK_BIAS) & 0x7) + goto segv; + + err = __get_user(tpc, &sf->regs.tpc); err |= __get_user(tnpc, &sf->regs.tnpc); if (test_thread_flag(TIF_32BIT)) { tpc &= 0xffffffff; @@ -308,14 +325,6 @@ segv: force_sig(SIGSEGV, current); } -/* Checks if the fp is valid */ -static int invalid_frame_pointer(void __user *fp) -{ - if (((unsigned long) fp) & 15) - return 1; - return 0; -} - static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize) { unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS; |