On Tue, Sep 19, 2023 at 01:05:07PM +0300, Dmitry Chagin wrote: > On Tue, Sep 19, 2023 at 12:05:42AM +0300, Konstantin Belousov wrote: > > On Mon, Sep 18, 2023 at 02:53:25PM +0000, Dmitry Chagin wrote: > > > The branch main has been updated by dchagin: > > > > > > URL: > > > https://cgit.FreeBSD.org/src/commit/?id=227d01c1bc7caf2e838ee6eef1e6a3cc81d79d1b > > > > > > commit 227d01c1bc7caf2e838ee6eef1e6a3cc81d79d1b > > > Author: Dmitry Chagin <dcha...@freebsd.org> > > > AuthorDate: 2023-09-18 14:53:01 +0000 > > > Commit: Dmitry Chagin <dcha...@freebsd.org> > > > CommitDate: 2023-09-18 14:53:01 +0000 > > > > > > linux(4): On Linux SIGKILL can not be reset to default > > > > > > MFC after: 1 week > > > --- > > > sys/compat/linux/linux_signal.c | 5 ++++- > > > 1 file changed, 4 insertions(+), 1 deletion(-) > > > > > > diff --git a/sys/compat/linux/linux_signal.c > > > b/sys/compat/linux/linux_signal.c > > > index e3e3fc74a6a9..9a84700b3949 100644 > > > --- a/sys/compat/linux/linux_signal.c > > > +++ b/sys/compat/linux/linux_signal.c > > > @@ -170,6 +170,7 @@ linux_do_sigaction(struct thread *td, int linux_sig, > > > l_sigaction_t *linux_nsa, > > > > > > if (!LINUX_SIG_VALID(linux_sig)) > > > return (EINVAL); > > > + sig = linux_to_bsd_signal(linux_sig); > > > > > > osa = (linux_osa != NULL) ? &oact : NULL; > > > if (linux_nsa != NULL) { > > > @@ -180,9 +181,11 @@ linux_do_sigaction(struct thread *td, int linux_sig, > > > l_sigaction_t *linux_nsa, > > > linux_ktrsigset(&linux_nsa->lsa_mask, > > > sizeof(linux_nsa->lsa_mask)); > > > #endif > > > + if ((sig == SIGKILL || sig == SIGSTOP) && > > > + nsa->sa_handler == SIG_DFL) > > > + return (EINVAL); > > This is excessive: look at kern_sigaction() around line 822. > > > > Well, I checkd that before, Bruce added this check a long time ago, > however, Bruce's change allows the handler to be set to SIG_DFL. > And I haven't found an explicit statement of how it should be in POSIX, > so I think it's Linux specific >
If kern_sigaction() allows to change SIGKILL or SIGSTOP disposition from default, we have a serious issue. The check above simply repeats the check from kern_sigaction().
