diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2012-11-18 22:27:03 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-12-03 12:59:14 -0800 |
| commit | bf7ef7e4c2fdcba5862aca37e49a66172069b44f (patch) | |
| tree | 26439a463bf14d451f7da4551fb0833fe12ad751 | |
| parent | 1c4e871038f17769d943d4473c339171fed70f45 (diff) | |
sparc64: not any error from do_sigaltstack() should fail rt_sigreturn()
commit fae2ae2a900a5c7bb385fe4075f343e7e2d5daa2 upstream.
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.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | arch/sparc/kernel/signal_64.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/arch/sparc/kernel/signal_64.c b/arch/sparc/kernel/signal_64.c index d58260bff2df..77d476175dc6 100644 --- a/arch/sparc/kernel/signal_64.c +++ b/arch/sparc/kernel/signal_64.c @@ -309,9 +309,7 @@ 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); |