On Sun, Nov 18, 2012 at 08:30:05PM -0500, David Miller wrote: > > Er... So which tree should that go through? sparc or signal? There's > > a similar microblaze patch and a few more of the "do_sigaltstack() takes > > userland pointer" variety, so I can put together a pile in > > signal.git#for-linus, but if you prefer that to go through sparc tree, > > I'm fine with that... > > I'm happy to take it via my sparc tree, and I'll queue it up for > -stable as well. Can you resend it to me with a proper commit message? sparc64: not any error from do_sigaltstack() should fail rt_sigreturn() If a signal handler is executed on altstack and another signal comes, we will end up with rt_sigreturn() on return from the second handler getting -EPERM from do_sigaltstack(). It's perfectly OK, since we are not asking to change the settings; in fact, they couldn't have been changed during the second handler execution exactly because we'd been on altstack all along. 64bit sigreturn on sparc treats any error from do_sigaltstack() as "SIGSEGV now"; we need to switch to the same semantics we are using on other architectures. Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> --- diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index 867de2f..689e1ba 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -295,9 +295,7 @@ void do_rt_sigreturn(struct pt_regs *regs) err |= restore_fpu_state(regs, fpu_save); err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t)); - err |= do_sigaltstack(&sf->stack, NULL, (unsigned long)sf); - - if (err) + if (err || do_sigaltstack(&sf->stack, NULL, (unsigned long)sf) == -EFAULT) goto segv; err |= __get_user(rwin_save, &sf->rwin_save); -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
