From a3f61dc0a5335334958ec3b97d0b1946b4ae5375 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Mon, 4 Jun 2007 17:22:48 +1000 Subject: [POWERPC] Merge creation of signal frame The code for creating signal frames was still duplicated and split in strange ways between 32 and 64 bits, including the SA_ONSTACK handling being in do_signal on 32 bits but inside handle_rt_signal on 64 bits etc... This moves the 64 bits get_sigframe() to the generic signal.c, cleans it a bit, moves the access_ok() call done by all callers to it as well, and adapts/cleanups the 3 different signal handling cases to use that common function. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras --- arch/powerpc/kernel/signal_32.c | 52 +++++++++++++++++++---------------------- 1 file changed, 24 insertions(+), 28 deletions(-) (limited to 'arch/powerpc/kernel/signal_32.c') diff --git a/arch/powerpc/kernel/signal_32.c b/arch/powerpc/kernel/signal_32.c index 32481e71d71e..590057e9e987 100644 --- a/arch/powerpc/kernel/signal_32.c +++ b/arch/powerpc/kernel/signal_32.c @@ -282,14 +282,17 @@ long sys_sigaction(int sig, struct old_sigaction __user *act, /* * When we have signals to deliver, we set up on the * user stack, going down from the original stack pointer: - * a sigregs struct + * an ABI gap of 56 words + * an mcontext struct * a sigcontext struct * a gap of __SIGNAL_FRAMESIZE bytes * - * Each of these things must be a multiple of 16 bytes in size. + * Each of these things must be a multiple of 16 bytes in size. The following + * structure represent all of this except the __SIGNAL_FRAMESIZE gap * */ -struct sigregs { +struct sigframe { + struct sigcontext sctx; /* the sigcontext */ struct mcontext mctx; /* all the register values */ /* * Programs using the rs6000/xcoff abi can save up to 19 gp @@ -698,21 +701,16 @@ int compat_sys_sigaltstack(u32 __new, u32 __old, int r5, */ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset, - struct pt_regs *regs, unsigned long newsp) + struct pt_regs *regs) { struct rt_sigframe __user *rt_sf; struct mcontext __user *frame; - unsigned long origsp = newsp; + unsigned long newsp = 0; /* Set up Signal Frame */ /* Put a Real Time Context onto stack */ - newsp -= sizeof(*rt_sf); - rt_sf = (struct rt_sigframe __user *)newsp; - - /* create a stack frame for the caller of the handler */ - newsp -= __SIGNAL_FRAMESIZE + 16; - - if (!access_ok(VERIFY_WRITE, (void __user *)newsp, origsp - newsp)) + rt_sf = get_sigframe(ka, regs, sizeof(*rt_sf)); + if (unlikely(rt_sf == NULL)) goto badframe; /* Put the siginfo & fill in most of the ucontext */ @@ -742,8 +740,12 @@ int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka, current->thread.fpscr.val = 0; /* turn off all fp exceptions */ + /* create a stack frame for the caller of the handler */ + newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16); if (put_user(regs->gpr[1], (u32 __user *)newsp)) goto badframe; + + /* Fill registers for signal handler */ regs->gpr[1] = newsp; regs->gpr[3] = sig; regs->gpr[4] = (unsigned long) &rt_sf->info; @@ -988,26 +990,17 @@ int sys_debug_setcontext(struct ucontext __user *ctx, * OK, we're invoking a handler */ int handle_signal32(unsigned long sig, struct k_sigaction *ka, - siginfo_t *info, sigset_t *oldset, struct pt_regs *regs, - unsigned long newsp) + siginfo_t *info, sigset_t *oldset, struct pt_regs *regs) { struct sigcontext __user *sc; - struct sigregs __user *frame; - unsigned long origsp = newsp; + struct sigframe __user *frame; + unsigned long newsp = 0; /* Set up Signal Frame */ - newsp -= sizeof(struct sigregs); - frame = (struct sigregs __user *) newsp; - - /* Put a sigcontext on the stack */ - newsp -= sizeof(*sc); - sc = (struct sigcontext __user *) newsp; - - /* create a stack frame for the caller of the handler */ - newsp -= __SIGNAL_FRAMESIZE; - - if (!access_ok(VERIFY_WRITE, (void __user *) newsp, origsp - newsp)) + frame = get_sigframe(ka, regs, sizeof(*frame)); + if (unlikely(frame == NULL)) goto badframe; + sc = (struct sigcontext __user *) &frame->sctx; #if _NSIG != 64 #error "Please adjust handle_signal()" @@ -1019,7 +1012,7 @@ int handle_signal32(unsigned long sig, struct k_sigaction *ka, #else || __put_user(oldset->sig[1], &sc->_unused[3]) #endif - || __put_user(to_user_ptr(frame), &sc->regs) + || __put_user(to_user_ptr(&frame->mctx), &sc->regs) || __put_user(sig, &sc->signal)) goto badframe; @@ -1035,8 +1028,11 @@ int handle_signal32(unsigned long sig, struct k_sigaction *ka, current->thread.fpscr.val = 0; /* turn off all fp exceptions */ + /* create a stack frame for the caller of the handler */ + newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE; if (put_user(regs->gpr[1], (u32 __user *)newsp)) goto badframe; + regs->gpr[1] = newsp; regs->gpr[3] = sig; regs->gpr[4] = (unsigned long) sc; -- cgit v1.2.1